NAVLE Sample Questions I Flashcards

Question

An Atlantic salmon net pen operator calls you with concerns about loss of fish during the seawater phase of rearing. They report that especially during warm temperatures, fish experience high mortality due to Vibriosis. They are currently using florfenicol-medicated feed to treat these outbreaks. The net pen operator is concerned about the consequences of the repeated antibiotic treatments they are administering, and they are looking to you for alternative options for managing Vibriosis. **You inform them that** - Net pens are a biosecure environment and should not have Vibriosis. - Vaccines are excellent for managing Vibriosis. - Antibiotics are the only option to manage Vibriosis. - Ampicillin is a superior antibiotic for Vibriosis management.

Answer 1

Answer: **Vaccines are excellent for managing Vibriosis** Vibriosis is a common disease of saltwater fish, caused by Gram-negative rods in the Vibrio genus. Common clinical signs are hemorrhage, inflammation along the ventral and lateral body, ulcers, and petechiae on the fins, vent, and mouth. Net pens are not a biosecure environment because they are exposed to untreated water with wild fish and other animals that can cause disease in the fish being reared. Antibiotic medicated feeds may be prescribed by a veterinarian. Ampicillin is not an FDA-approved antibiotic medicated feed treatment and is illegal to use in these Atlantic salmon. Repeated use of antibiotics may cause resistance, and an excellent alternative to treatment is the prevention of Vibriosis via vaccines, such as Aquavac®. Vaccines for fish are often given orally via feed or via prolonged immersion in a bath.

Answer 2

Answer: **Pancreatic acinar atrophy** The correct answer is pancreatic acinar atrophy. This is an idiopathic condition where the exocrine cells of the pancreas atrophy with minimal inflammation. Chronic pancreatitis is a much more common cause of EP in cats than dogs. For this reason, dogs with EPI do not usually have concurrent diabetes mellitus because the endocrine cells are spared, whereas cats often do have concurrent DM. Neoplasia and infection are rare causes of EPI.

Answer 3

Answer: **Influenza virus** Hand sanitizing, alcohol based products are effective at killing many types of Gram positive and negative bacteria, including methicillin resistant Staphylococcus aureus (MRSA), tuberculosis, and E. coli. It is also effective against many types of fungi and enveloped viruses such as influenza viruses, HIV, and hepatitis virus (one exception is rabies virus). They are not effective against non-enveloped viruses (parvovirus), bacterial spores (Anthrax, C. difficile), and protozoan oocysts (Giardia, Isospora, Cryptosporidium).

Answer 4

Answer: **Cough** Explanation The correct answer is cough. Coughing is typically a sign of left heart failure that occurs with the development of pulmonary edema and/or bronchial compression from an enlarged left atrium. In right heart failure, tachypnea and dyspnea can develop due to pleural effusion. Hepatomegaly occurs due to venous congestion from the damming of blood into the liver. Exercise intolerance develops because a decrease in cardiac output causes a decrease in oxygenation of tissues. Muscle wasting occurs from loss of protein into effusions and from hepatic and Gl malfunction. Other signs of right heart failure include lethargy, weakness, venous distention, ascites, and peripheral edema.

Answer 5

Answer: **Fenbendazole** The organism is Giardia which can be recognized as a trophozoite with two nuclei outlined by adhesive discs. Giardia should be distinguishable from trichomonads which have a single nucleus and an undulating membrane. The best treatments for Giardia are either fenbendazole or metronidazole.

Answer 6

Answer: **Posterior paresis** Explanation The correct answer is posterior paresis. Hypovitaminosis A most commonly affects box turtles that are fed imbalanced diets of fruit and insects that have little vitamin A. Clinical signs include edema of the eyelids, chronic respiratory disease, renal disease (due to the squamous metaplasia of renal tubules blocking collecting ducts), squamous metaplasia of epithelium, and secondary infections of the eyes, skin, and respiratory system. Treatment includes oral or parenteral vitamin A supplementation.

Answer 7

Answer: **HO occurs in association with a thoracic mass** Explanation The correct answer is HO occurs in association with a thoracic mass. There is no breed or age predisposition for HO. The disease usually starts at the distal extremities and develops proximally. HO is characterized by periosteal proliferation near joints, not sclerosis of the subchondral bone.

Answer 8

Answer: **Uterine adenocarcinoma.** Uterine adenocarcinoma is the most common neoplasia of female rabbits, with up to 80% incidence among intact females of certain species. Because of this, all female rabbits that are not breeders should be spayed. The most common signs of uterine ACA are hematuria, anorexia, depression, dysuria, and milk production. Pregnancy would be unlikely to cause hematuria. Rabbits are induced ovulators and do not exhibit estrous. Hematuria must be distinguished from porphyrinuria, which is a normal red or orange pigment in the urine of some rabbits. However, porphyrinuria does not cause anorexia and weight loss. Rabbit syphilis is a sexually transmitted disease caused by Treponema paraluis cuniculi. It causes perineal lesions but does not cause hematuria.

Answer 9

Answer: **P=ID** The correct formula to use is P = 1 x D. Prevalence can generally be viewed as the product of incidence and disease duration. Incidence is defined as the number of new cases of a disease in a given period, and prevalence is the number of total cases prevailing (counted) in the given period. This formula is helpful in a clinical scenario to help evaluate risk. Prevalence can increase (or decrease) in two ways: 1) the number of new cases (incidence) increases (or decreases), and 2) the duration of disease increases (or decreases). If a disease goes untreated, for example, duration would likely increase (compared to treated cases), and prevalence would increase. Similarly, if the risk of acquiring a disease increased, the prevalence would increase. Note, for example, that if the weekly incidence of a disease were 5 new cases and the duration was 2 weeks per case (on average), generally one would expect the weekly prevalence to be 5 cases/week x 2 weeks = 10. Ref: Veterinary Epidemiology: Principles and Methods, 1987 pg. 81, Martin, Meek, Willeberg

Answer 10

Answer: Gastrointestinal ulcer formation, inhibition of platelet function, analgesia Explanation The correct answer is gastrointestinal ulcer formation, inhibition of platelet function, analgesia. NSAIDs reduce inflammation and pain by blocking the COX-1 and COX-2 pathways. Non-selective COX inhibitor side effects include Gl ulcers, inhibition of platelet function, renal damage, and reduction of fever.

Answer 11

Answer: 19 -26 days Explanation The correct answer is 19-26 days. Estrus in a mare can last 2-10 days but, on average, is 6 days long. The mare is a polyestrous animal from the beginning of spring through summer. The estrous cycle's duration lasts 19-26 days.

Answer 12

Answer: **Evidence of prior hemorrhage** Explanation The correct answer is evidence of prior hemorrhage. This is that yellow discoloration that can be seen for at least a week after bleeding in the CSF. A black discoloration would be diagnostic for melanoma.

Answer 13

Answer: Plasma glucocorticoid and heart rate levels Explanation Elevated plasma glucocorticoid levels and heart rate are associated with stress responses and are easily measurable, accurate indicators of welfare.

Answer 14

Answer: **Respiratory acidosis** The correct answer is respiratory acidosis. There is bound to be some sort of acid-base question on the exam. This question might look tricky, but it is truly simple. Think about the information you are given; all you know is the dog is hypoventilating. So there is build up of CO2; in effect the dog is in respiratory acidosis. Remember, CO2=Acid. Since you have no other information, there is no way to diagnose a metabolic acidosis or alkalosis. Some causes of respiratory acidosis include airway obstruction, open pneumothorax or flail chest, neuromuscular disease, abdominal enlargement, pleural space disease, and bicarbonate therapy.

Answer 15

Answer: **Arterial oxygen pressure is 60 mm Hg, and oxygen saturation may drop precipitously if it decreases further** When assessing an anesthetized patient with pulse oximetry, it is important to realize several things: *- The shape of the oxygen saturation curve is sigmoid, and until you reach oxygen pressures of < 60 mm Hg, there is very little change in oxygen saturation. Because an anesthetized patient breathing 100% oxygen should have about 500 mm Hg oxygen in the arterial blood, this can drop a long way before a dramatic change to oxygen saturation occurs.* However, the time to intervene is early when you see saturation percentages decrease because it means that your patient is oxygenating very poorly, especially if they are breathing 100% oxygen, and even a relatively small further decline could dramatically reduce their oxygen saturation, resulting in tissue hypoxia and dangerous consequences. An oxygen saturation of 98-100% corresponds to > 100 mm Hg oxygen in arterial blood An oxygen saturation of 95% corresponds to 80 mm Hg An oxygen saturation of 90% corresponds to 60 mm Hg An oxygen saturation of 50% corresponds to 30 mm Hg An oxygen saturation of 10% corresponds to 10 mm Hg By the way, in room air, arterial oxygen pressure should normally be 80-100 mm Hg and oxygen saturation is 95-100%

Answer 16

Answer: **Antibiotics** Explanation The correct answer is antibiotics. *Proliferative bowel disease* in ferrets is caused by Lawsonia, an intracellular bacterium. The organism is very susceptible to chloramphenicol and has a variable susceptibility to other antibiotics.

Answer 17

Answer: **Positional, vertical nystagmus.** Explanation The correct answer is positional, vertical nystagmus. Positional and vertical nystagmus only occur with central vestibular disease. Circling, head tilt, and horizontal nystagmus all occur with either central or peripheral vestibular disease.

Answer 18

Answer: **The lesions can be internal and external, so dental radiographs should be taken to further investigate the extent of the lesions** The correct answer is the lesions can be internal and external, so dental radiographs should be taken to further investigate the extent of the lesions. FORL lesions are usually very painful and are more common now than before. Up to 67% of cats presenting for dental care may be affected. The exact etiology of FORL is not known, but studies have shown an association of FORL and diets low in calcium, magnesium, phosphorus, and potassium. Periodontal disease is also often found in association with FORL. Treatment should include addressing associated periodontal disease and possibly extraction of teeth affected by deep lesions.

Answer 19

Answer: **Fluconazole** Explanation The cytology from the fine needle aspirate shows cryptococcus. *Cryptococcus* is an encapsulated fungus and is treated with anti-fungal medications such as fluconazole or itraconazole. Clindamycin is used to treat toxoplasma. Fenbendazole is used to treat intestinal parasites such as hookworms, roundworms, and Giardia. Chlorambucil is a chemotherapeutic agent often used in treating lymphoma.

Answer 20

Answer: **MRI of the brain** Explanation This cat has clinical signs most consistent with acromegaly (weight gain, prognathism, organomegaly, and diabetes mellitus that is difficult to control). This condition results from a growth hormone (GH) secreting pituitary tumor. GH or insuline-like growth factor (IGF) assays can be diagnostic but are not offered by many veterinary laboratories. Advanced imaging techniques are the most reliable way to diagnose a pituitary mass in this instance. This cat is not likely to be hyperthyroid due to the history of weight gain. Hyperadrenocorticism as a cause of insulin-resistant diabetes mellitus is less likely given the cat's other clinical signs; nevertheless, adrenal function testing such as an ACTH stimulation test or dexamethasone suppression test to rule out hyperadrenocorticism should be considered.

Answer 21

Answer: **A current DEA license** Hydrocodone is a controlled substance. Controlled substances cannot be prescribed unless the veterinarian holds a current DEA license. Pharmacists require a DEA number in order to process these prescriptions. A premise license is held by the owner of the building of the veterinary hospital. A conversation with the owner of possible side effects of any medications sent with the pet should occur, but a written list is not required by law.

Answer 22

Answer: **Give the technicians a four-week timeframe to review assigned materials, achieve at least an 80% score on a written examination, and pass an oral examination regarding diabetes education for dog and cat owners.** Goals should be set using SMART objectives: specific, measurable, attainable, realistic, and timed. This option has a clearly defined timeline and objective. The 80% score goal is measurable. Also, a strategy for achieving an outcome is clearly identified. No specific strategy for achieving these changes is identified in the incorrect options. A one-week timeframe to achieve a perfect score is not realistic and therefore not attainable. Options which do not include a specific measure of success are incorrect. Source: Handbook of Veterinary Communication Skills. Edited by Carol Gray and Jenny Moffett. Wiley-Blackwell, 2010. Pages 134-136.

Answer 23

Answer: **Create a written standard operating procedure for submission of laboratory samples.** Creating a written standard operating procedure (SOP) for submission of laboratory samples is the best option for prevention of future labeling errors. Written SOPs are the best way to ensure that team members adhere to established procedures for frequently occurring processes. Talking privately with the assistant who mislabeled the tubes and/or taking disciplinary action against that team member may be appropriate options, however this will not reduce the chances of a future labeling mistake by another team member. Holding a staff meeting to discuss proper procedures is important, however this will not reduce the chances of a future labeling mistake by new employees or anyone not in attendance at the meeting. Source: Handbook of Veterinary Communication Skills. Edited by Carol Gray and Jenny Moffett. Wiley-Blackwell, 2010. Pages 136-138.

Answer 24

Answer: **Prescribing medications to a patient with roundworms** In a well-run practice, veterinarians should be performing the tasks that they alone are qualified to do, namely to make a diagnosis and prognosis, prescribe drugs, and perform surgery. Technical tasks should be performed by technicians including surgical assisting, laboratory procedures, radiography, anesthesia, patient treatment and nursing, and client education. Veterinary assistants have no AVMA-accredited training programs and act as support for veterinarians and technicians, for tasks that do not require the higher level of training or expertise. These generally include patient handling and restraint and assisting with various radiographic, laboratory, and pharmaceutical tasks. It is critical that they have documented skill and safety training for any technical tasks that they perform.

Answer 25

Answer: **120ml/kg** Explanation The correct answer is 120 ml/kg day. This is considerably higher than a dog or cat.

Answer 26

Answer: **Doxorubicin. Cold compress to contain the spread of drug** Explanation Intravenous chemotherapy drugs can cause severe tissue necrosis (doxorubicin) or irritation (vincristine) if extravasation occurs. Treatment for both should begin immediately. In both cases, the catheter should be left in place and as much of the drug should be aspirated as possible. Treatment for doxorubicin extravasation involves cold compressing the site to promote vasoconstriction, however perivascular necrosis may still occur and may progress days to weeks later. In severe cases involving doxorubicin, debridement or limb amputation may be needed. Vincristine extravasation should be treated with warm compresses to disperse the drug and enhance systemic absorption. Extravasation should be prevented through patient restraint training, use of catheters that have been placed on the first stick, and careful monitoring during administration. The peripheral veins should be avoided for blood draws if possible on all patients receiving chemotherapy.

Answer 27

Answer: **The prognosis is good with antibiotic treatment.** The top differential diagnosis for this case is "Furunculosis" caused by Aeromonas salmonicida. The classic clinical sign is large, swollen skin lesions mistakenly referred to as "furuncles" (since fish don't have hair). Other clinical signs include hemorrhage, kidney and vent swelling, and ulcers. For food fish, furunculosis may be treated with oxytetracycline, sulfadimethoxine and ormetoprim, and florenicol medicated feeds via a Veterinary Feed Directive. In a koi pond, you may use injectable antibiotics if the population is small. If left untreated, furunculosis may lead to serious mortality. Koi herpesvirus (Cyprinid herpesvirus Type 3) is not a top differential because mortality at this temperature would be extremely high, approaching 80-100% if new fish had been introduced several months ago. Clinical signs of KHV include gill necrosis and enophthalmia. The clinical signs in this case are also not indicative of Spring Viremia of Carp. Spring Viremia of Carp would present with extremely high mortality and internal ecchymotic hemorrhages. SVC also usually presents at a lower temperature (50-64°F). A quarantine protocol and improved biosecurity measures may be helpful to discuss with the owner since they introduced new fish recently.

Answer 28

answer: **Schedule a meeting with the office manager to review the project timeline.** Following delegation of a task, defining a project timeline is recommended. Performance should be tracked throughout the project. Avoid undermining the delegated responsibility. Delegation of tasks does not mean abdication of responsibility. Regular check-ins should be scheduled with the employee who is in charge of the delegated tasks. Completing tasks that have been delegated to another team member, or delegating those tasks to a new team member, undermines that team member's responsibilities and authority. Source: The Art of Veterinary Practice Management. Mark Opperman and Sheila Grosdidier. Advanstar Communications, Inc., 2014. Page 104-105.

Answer 29

Answer: **Immune mediated hemolytic anemia** The image shows a positive slide agglutination test. The dark patches in the sample are caused by antibodies attached to the surface of the erythrocytes cross linking the cells together causing these clumps. This is highly suggestive of an immune mediated reaction to antigen on the individual's red blood cells. Rouleaux formations are red blood cells stacked together as a result of their natural discoid shape and large surface area causing them to have an affinity for each other. They typically resemble a stack of coins or cookies. Evan's syndrome is an autoimmune condition characterized by an immune attack on erythrocytes, platelets, and occasionally leukocytes as well. You would not be able to diagnose this on a slide agglutination test alone. Vitamin K antagonist toxicity with rodenticide causes a coagulopathy but should not cause hemagglutination.

Answer 30

Answer: Via mosquitoes Mosquito vectors are the primary mode of transmission for WNV between birds and other hosts (horses, humans). There are infrequent documented cases of the disease being spread by feces or saliva. No mites have been documented to transmit the disease. Birds do not have a placenta. West Nile Viral Infection in Equids: NAVLE Study Guide Definitions and Causative Agents • West Nile Virus (WNV): A Flavivirus transmitted by mosquitoes, causing encephalitis in equids. Horses are considered “dead-end” hosts, as they do not spread the virus further. Pathogenesis • Virus Structure: The virus has an RNA genome that encodes structural proteins (C-prM-E) and nonstructural proteins (NS1-NS5). • Transmission Cycle: WNV is maintained in a bird-mosquito cycle. Horses become infected through mosquito bites, developing subclinical or clinical neurological disease. Clinical Signs • Symptoms: Ataxia, limb weakness, recumbency, muscle fasciculations, hyperesthesia, and cranial nerve deficits like facial nerve paralysis. Severe cases may lead to tetraplegia and death. • Fatality Rate: Ranges from 22% to 44% in clinical cases. Diagnosis • Tests: Real-time RT-PCR to detect viral RNA, ELISA for detecting IgM antibodies, and post-mortem immunohistochemistry in nervous tissues. • Considerations: WNV viremia is short, making early detection challenging. IgM antibodies indicate recent infection, whereas IgG antibodies may persist from vaccination or past exposure. Treatment • Supportive Care: Includes anti-inflammatory drugs, fluids, and measures to reduce stimuli (e.g., padded stalls). • Experimental Therapies: Use of WNV antibodies and antiviral drugs like ribavirin and interferon, though no proven efficacy in horses. Prevention • Vaccination: Several vaccines are available, including inactivated virus vaccines and recombinant vaccines using canarypox vectors. Annual boosters are recommended. • Mosquito Control: Essential to reduce exposure; involves minimizing outdoor activity during peak mosquito times and using repellents. Pathology • Histopathological Findings: Mild to severe polioencephalomyelitis, with lesions primarily in the brainstem and spinal cord. Neuronophagia and perivascular infiltrates are common. Prognosis • Outcome: Varies; many horses recover, but some have residual neurological deficits.

Answer 31

Answer: **Parathyroid hormone (PTH), calcitonin, and 1,25-dihydroxycholecalciferol D3** Explanation PTH comes from parathyroid chief cells in response to hypocalcemia. Calcitonin is from thyroid parafollicular glands in response to hypercalcemia. 1,25-dihydroxycholecalciferol D3 is of renal origin and sometimes called calcitriol. *Ionized serum calcium levels are regulated by three key hormones: Parathyroid hormone (PTH), calcitonin, and 1,25-dihydroxycholecalciferol D3 (calcitriol). PTH is secreted by parathyroid chief cells in response to low calcium levels, calcitonin by thyroid parafollicular cells in response to high calcium, and 1,25-dihydroxycholecalciferol D3 is produced by the kidneys.*

Answer 32

Answer: **The HPAl can transfer genes from pig or human influenza strains, which allow the avian flu to become infectious to humans** Explanation While the highly pathogenic avian influenza strains can kill domestic ducks and poultry, they do not normally cause major public health issues unless they acquire the genes that allow them to attach to human respiratory mucosa and become pathogenic for humans. This is how a worldwide influenza pandemic could occur.

Answer 33

Answer: **Early return to function** Explanation The correct answer is early return to function. With articular fractures, the 3 major goals of the clinician are: Rigid fixation of the fracture fragments; neglecting to do this will result in loose fracture fragments within the joints that will promote osteoarthritis. Anatomic realignment (50% or even 75% is not adequate with articular fractures, in contrast to long bone fractures). Early return to function. With long bone fractures, extended rest is recommended to promote stability and healing of the bone. The opposite is true in articular fractures where prolonged rest after repair will promote fibrosis, causing decreased range of motion in the joint.

Answer 34

Answer: **Campylobacteriosis** Explanation The correct answer is Campylobacteriosis. This is a gram negative motile, thin, S-shaped or gull-shaped rod. It can occur singly, in pairs, or in chains. C. jejuni is most commonly isolated. You can also isolate this organism with fresh fecal swabs streaked onto Campylobacter blood agar plates, which grows in an oxygen-reduced atmosphere in 3-4 days. Salmonella is a gram-negative bacillus. C. difficile is a gram-positive rod. Cryptosporidium is a coccidian parasite. Fun Fact: Kids with puppies are 16 times more likely to acquire Campylobacteriosis.

Answer 35

Answer: **Gram negative bacteria in blood or tissues** Explanation Fowl cholera is caused by Pasteurella multocida, a Gram negative, non motile, pleomorphic rod. As with most poultry diseases, it is preferable to prevent introduction of the disease into a flock with biosecurity measures. If treatment is attempted, it should ideally be based on culture and sensitivity but sulfonamides, tetracyclines, or penicillin are most often used. Intranuclear inclusion bodies from the tracheal epithelium are seen with Infectious Laryngotracheitis caused by a herpesvirus. Fowlpox virus produces intracytoplasmic inclusions. Liver necrosis with large, granular basophilic intracytoplasmic inclusions is consistent with avian chlamydiosis.

Answer 36

Answer: **In ovo injection of live virus at day 8 of incubation** Explanation The Marek's disease vaccine is recommended for in ovo vaccination of 18- to 19-day-old healthy embryonated chicken eggs. The vaccine may also be used for subcutaneous vaccination of healthy one-day-old chickens, but in large-volume chicken hatcheries, the in ovo method is used.

Answer 37

Answer: **Hyperkalemic periodic paralysis** Explanation The correct answer is *hyperkalemic periodic paralysis (HYPP)*. HYPP is seen in Quarter Horses due to a point mutation in a key part of a skeletal muscle sodium channel subunit. This results in elevation of the resting membrane potential to increase the likelihood of depolarizing. Excess concentrations of potassium can result in failure of the sodium channels to inactivate. Therefore, treatment is directed at decreasing dietary potassium.

Answer 38

Answer: **Ulcerative skin lesions.** The correct answer ulcerative skin lesions. About 7% of dogs using Itraconazole will develop ulcerative skin lesions when used at a higher dosage rate. Decreased appetite, nausea, and diarrhea may also be seen. Nephrotoxicity is seen when using Amphotericin B. Hyperactivity and neurologic symptoms are not known side effects. **Coccidioidomycosis in Animals - Comprehensive Veterinary Information** Definitions and Terminology: • Coccidioidomycosis (Valley Fever): A dustborne, noncontagious fungal infection caused by Coccidioides spp. fungi. Causative Agents: • Species: Coccidioides immitis and Coccidioides posadasii. Physiopathology: • Transmission: Inhalation of arthrospores from contaminated dust. • Pathogenesis: Fungi form spherules in the lungs, which can disseminate to other organs. Clinical Findings: • Dogs: Chronic respiratory disease, cough, fever, lethargy, anorexia, and weight loss. Disseminated disease can affect the CNS, skin, bones, eyes. • Cats: Dermatologic signs, fever, weight loss, respiratory issues, lameness, neurologic and ophthalmologic abnormalities. • Horses: Placental infection, abortion, osteomyelitis. • Ruminants and Pigs: Subclinical infections with lung lesions. Diagnosis: • Histopathology: Identification of spherules in tissues. • Serologic Testing: AGID, EIA, LFA for antibodies. • MRI: Useful for CNS involvement. • CSF Analysis: EIA for antigen and antibodies. Treatment: • Antifungal Therapy: Fluconazole (5-10 mg/kg, q24h) or itraconazole (10 mg/kg, q24h) for 6-12 months. • Surgery: For excision of granulomas when feasible. • Supportive Care: Necessary for chronic cases. Prognosis: • Guarded to Good: Depending on the extent of disease and response to treatment.

Answer 39

Answer: **Lipoma.** The cells depicted are well-differentiated adipocytes. These cells are large, appear in aggregates or sometimes singly, and contain fat that stains negatively with Wright's, such that the cytoplasm appears clear. The cells possess a small, round or ovoid, pyknotic nucleus that may be compressed and located in the periphery of the cell. This benign tumor is a lipoma, which is common in dogs. If the mass hinders the animal, it may be removed surgically. Infiltrative lipomas, and their malignant counterpart, liposarcomas, are less common. When sampling for cytology, frequently the first indication that a lipoma has been aspirated is the clear, oily appearance of the material ejected from the aspiration needle onto the slide. Care must be taken while staining to ensure that the material does not wash off the slide, as fat does not adhere readily to the glass surface. Note: Gentle heat fixing of greasy material to a slide may be of benefit in keeping adipose cells adherent to slides during staining. This can be accomplished by holding a slide over a Bunsen burner or lighter or gentle heating on a heating tray/bar for a few seconds so that the side opposite to that containing the cellular material is slowly warmed. The slide must be left to cool completely before staining. Slides coated with poly-l-lysine, which are used for Papanicolaou staining and/or increased adherence of tissue sections to slides, are also helpful in promoting cellular adherence and eliminating loss of cells during staining. Sometimes, local fat will be aspirated and cannot be reliably differentiated from the adipose cells of a lipoma. If there is any doubt as to the presence of a discrete mass, surgical removal with histological evaluation is recommended.

Answer 40

Answer: **Dermatophilosis** Dermatophilosis is a crusting dermatitis caused by the filamentous bacteria Dermatophilus congolensis, seen in all ruminants and horses. Also called "lumpy wool" or "rain scald/rot." Infection is seen most often in younger or systemically ill/immunocompromised animals. Many are housed in areas with poor hygiene or without shelter. Excessive moisture, rainy conditions, skin damage, and concurrent illness that results in immunosuppression are predisposing factors. Loss of the protective sebaceous film layer seen on healthy skin is thought to be an important factor in the pathogenesis. Carrier animals and fomites such as grooming tools are also important as this can be contagious in at-risk animals. Thick crusts, which usually contain the organism, look like the end of a paint brush when removed from the animal and are a typical finding. On cytology (impression smear of a crust) the "railroad track" appearance of the gram-positive cocci is classic for dermatophilosis. The infection self-resolves after a few weeks in most animals without treatment. Can use topical and systemic antimicrobials in persistent cases. Link: Dermatophiolosis (“Rain Rot”) in Horses https://www.merckvetmanual.com/horse-owners/skin-disorders-of-horses/dermatophilosis-rain-rot-in-horses?autoredirectid=22723

Answer 41

Answer: **A high-dose dexamethasone suppression test could help differentiate pituitary versus adrenal dependent hyperadrenocorticism** Explanation The correct answer is you should run a *high-dose dexamethasone suppression test*. Elevated blood cortisol concentration 4 hours and 8 hours post low-dose dexamethasone administration is diagnostic for hyperadrenocorticism, but it does not allow differentiation between PDH and a cortisol secreting adrenal tumor. Dexamethasone is more rapidly metabolized in dogs with either type of hyperadrenocorticism (approximately 4 hours to metabolize as opposed to 30 hours in normal dogs). In PDH animals, the 4-hour post-cortisol concentration may sometimes be suppressed, whereas cortisol from adrenal tumors will not be suppressed after administration of a low dose of dexamethasone. A high-dose dexamethasone test will suppress a larger percentage of PDH patients (up to 75% will be suppressed, showing a decrease in cortisol after 4 hours). Less reliable tests to differentiate PDH from an adrenal tumor include endogenous plasma ACTH concentration or abdominal ultrasound. For the PowerPage on this topic, view Hyperadrenocorticism (Cushing's Disease)

Answer 42

Answer: **Sudden Acquired Retinal Degeneration Syndrome (SARDS)** Explanation The correct answer is *SARDS*. SARDS is a condition seen usually in middle-aged obese female spayed dogs. They develop acute blindness and initially have no optic or fundoscopic lesions. In 1-2 months, they will develop retinal vascular attenuation and tapetal hyperreflectivity. A primary brain tumor would be more likely to show progressive signs. Retinal detachment and progressive retinal atrophy would show changes in the retina on fundic exam.

Answer 43

Answer: **Give 0.5mg/kg diazepam IV** Explanation It is likely that the radiographic contrast used in the myelogram has caused this seizure. Diazepam (or midazolam) is the first drug you should reach for in a seizuring dog. Re-anesthetizing the patient may not stop the seizure activity. KBr is loaded over several hours and would not be effective acutely; in addition, this is not a patient that should need maintenance therapy for seizures, and therefore would not benefit from a loading dose of KBr. Due to the inciting cause, hypoglycemia is unlikely to have caused the seizure and giving dextrose immediately is unnecessary.

Answer 44

Answer: **Create a written standard operating procedure for submission of laboratory samples.** Explanation Creating a written standard operating procedure (SOP) for submission of laboratory samples is the best option for prevention of future labeling errors. Written SOPs are the best way to ensure that team members adhere to established procedures for frequently occurring processes. Talking privately with the assistant who mislabeled the tubes and/or taking disciplinary action against that team member may be appropriate options, however this will not reduce the chances of a future labeling mistake by another team member. Holding a staff meeting to discuss proper procedures is important, however this will not reduce the chances of a future labeling mistake by new employees or anyone not in attendance at the meeting. Source: Handbook of Veterinary Communication Skills. Edited by Carol Gray and Jenny Moffett. Wiley-Blackwell, 2010. Pages 136-138.

Answer 45

Answer: **Apomorphine** Explanation The correct answer is apomorphine. Apomorphine is an opioid dopaminergic agonist that acts on the chemoreceptor trigger zone to induce vomiting in dogs. In can be administered IM, SC, IV, or in the conjunctival sac. Xylazine is a fairly effective emetic in the cat but is not used in the dog for this purpose. Azathioprine is an immunosuppressive drug not used to induce vomiting. Magnesium hydroxide or Milk of Magnesia is a cathartic but is not used for vomiting.

Answer 46

Answer: **High PaO2** Explanation The correct answer is high PaO2. PaCO2, blood pressure, Pa02, cerebral metabolism, and certain drugs can affect cerebral blood volume and intracranial pressure. In head trauma patients, you want to prevent an increase in intracranial pressure by keeping cerebral blood flow relatively low without causing hypoxia. To keep cerebral blood flow in the low-normal range, the cerebral metabolic rate and PaCO2 should be kept low. Factors that would cause the cerebral metabolic rate to go up include fever, seizures, pain, etc. Mean arterial pressure should be maintained in the normal range to prevent hypotension, hypoxia, and cerebral ischemia.

Answer 47

Answer: **Continue the antibiotics for another 2 weeks.** Explanation Deep pyodermas involve tissues deeper than the epidermis including the dermis and even subcutis. Most often deep infections have resulted from an uncontrolled superficial infection. Deep lesions usually heal on the surface before the deeper infection is resolved; making clinical cure difficult to assess. Therefore, antibiotic treatment should be continued for 7-21 days after the tissues return to normal. In general, deep infections can require 6-8 weeks of antibiotic treatment and even 12 weeks for severe cases. Superficial infections require 3-4 weeks of antibiotic therapy or one week past clinical resolution. Culture results will often be positive in normal dogs since normal dogs will have bacteria on their skin surface and in hair follicles. It is better to manage based on clinical signs. Cytology can miss deeper infections and it is better to extend antibiotic treatment even if cytology is negative. It is not necessary to continue the antibiotics until resolution of demodicosis. Keep in mind that many Demodex patients will require several months of treatment. It is better to prevent recurrence of bacterial infections with topical therapy such as benzoyl peroxide shampoos.

Answer 48

Answer: **Femoral Nerve Paralysis** Explanation *Femoral nerve paralysis* is not a reported complication. The surgical region is not near the femoral nerve. Incontinence can occur if over 50% of the external anal sphincter is damaged. Infection is a very common complication due to the region in which the surgery is being performed. Failure of repair is also a complication due to the weak nature of the muscles being used to repair the defect.

Answer 49

Answer: **0.9% sodium chloride** Explanation The most common electrolyte disturbance from a urethral obstruction is hyperkalemia. This occurs from an impaired urinary excretion of potassium. This can cause life-threatening arrhythmias and needs to be quickly addressed, especially if potassium exceeds 7 mEq/L. 0.9% Sodium chloride is the fluid of choice to treat this disturbance. If this fluid is not available, then Lactated Ringer's would be a good alternative due to the low potassium concentration in those fluids. In extreme cases, dextrose may need to be added to the fluids because this stimulates insulin secretion and helps to move the potassium intracellular. Sodium bicarbonate and calcium gluconate can also help this shift of potassium in extreme cases. **PowerPage: Urethral Obstruction (Feline)

Answer 50

Answer: **Humulin R (regular insulin)** Explanation This cat is in a state of diabetic ketoacidosis. Due to this status, the recommended insulin type is Humulin-R, or regular insulin. This is a shorter acting insulin which will help to get the ketonuria to resolve more efficiently. After the ketosis has resolved and the cat is hydrated, eating, drinking, and electrolytes are stable, the cat can be switched to a longer acting insulin. Glargine or PZI are the insulin types of choice for long term control in felines after the ketoacidosis has been corrected, but other insulin types can also be used.

Answer 51

Answer: **Llama** Explanation *Camelids* have ovoid anucleated erythrocytes. Mice and elephants have round erythrocytes. Frogs and chickens have nucleated erythrocytes. ***PowerPage Top 10 Things to Know for Camelids

Answer 52

Answer: **Craniodorsal** Explanation The correct answer is craniodorsal. Interestingly, over 80% of coxofemoral luxations occur in a craniodorsal direction in dogs. The key players in maintaining the femur in its socket are the ligament of the head of the femur, dorsal acetabular rim, and joint capsule. If any two of these are compromised, a luxation will most likely result. **PowerLecture: Hip Luxation

Answer 53

Answer: **2400 mEq** Explanation The best answer is 2400 mEq. The formula you need to know to calculate how much sodium bicarbonate you need (depending on your reference source) is 0.4 x BW × Base Deficit. Plug and chug (using 0.4) and you get 2444, which is the closest answer. In practice, you may choose to fix only part (often half) of the total calculated bicarbonate and reassess, but this question asks how much is needed to completely correct the deficit. If you need a reminder, the base deficit is the amount of base that you would need to add to a solution (i.e. plasma) to achieve a pH of 7.4. In general, the normal HCO3 concentration in blood is around 22-24 mEq/L. The base deficit is simply calculated by subtracting the patient's HCO3 concentration (i.e. 10 from the normal concentration [23]).

Answer 54

Answer: **Ingestion of moldy feed containing aflatoxins** Explanation This is a case of photosensitization based on the skin lesions confined to the nonpigmented areas. Primary photosensitization can occur when photodynamic agents are absorbed from the G.. tract such as Hypericum perforatum (St. John's wort), Fagopyrum esculentum (buckwheat), Ammi majus (bishop's weed), and Cymopterus watsonii (spring parsley). Secondary (hepatogenous) photosensitization occurs when the liver's excretion of phylloerythrin is impaired due to liver damage. Phylloerythrin is derived from the breakdown of chlorophyll by rumen microbes. The best answer in this question is aflatoxins because they are known to cause liver damage. Bracken fern toxicity causes acute hemorrhagic syndrome in cattle. Lupine toxicity primarily causes birth defects. Quercus (oak) toxicity causes Gl and renal dysfunction.

Answer 55

Answer: **Ingestion of moldy feed containing aflatoxins** Explanation This is a case of photosensitization based on the skin lesions confined to the nonpigmented areas. Primary photosensitization can occur when photodynamic agents are absorbed from the G.. tract such as Hypericum perforatum (St. John's wort), Fagopyrum esculentum (buckwheat), Ammi majus (bishop's weed), and Cymopterus watsonii (spring parsley). Secondary (hepatogenous) photosensitization occurs when the liver's excretion of phylloerythrin is impaired due to liver damage. Phylloerythrin is derived from the breakdown of chlorophyll by rumen microbes. The best answer in this question is aflatoxins because they are known to cause liver damage. Bracken fern toxicity causes acute hemorrhagic syndrome in cattle. Lupine toxicity primarily causes birth defects. Quercus (oak) toxicity causes Gl and renal dysfunction.

Answer 56

Answer: **Gravid female** Explanation The correct answer is gravid female. The clinical signs described are typical for a gravid female. They are most likely to present from November to June. On physical exam you can typically feel the lumps in the abdomen which are the large eggs. Intervention in the form of an ovariohysterectomy is performed if attempts at inducing oviposition fail.

Answer 57

Answer: **Due to the ability of the disease to cause pain.** Explanation Pain due to disease is a welfare concern. The other options are not welfare concerns associated with the disease.

Answer 58

Answer: **CNII** Explanation The correct answer is CN II. The presence of a palpebral indicates normal function of CN V and VII. The dazzle reflex examines CN Il separate of the visual cortex (an animal with a cortical lesion will still have a dazzle reflex). Therefore the lesion is in CN II.

Answer 59

Answer: **Left cranial lung lobe has alveolar infiltrates** This dog has pneumonia of the left cranial lung lobe. There are diffuse alveolar infiltrates within the left cranial lung lobe with air bronchograms. You should cancel the anesthetized procedure and wake up the patient because she is oxygenating poorly. Recheck radiographs are recommended once she is awake to rule out any component of atelectasis due to recumbency and sedation. There is an incidental gastric foreign body (rounded metal opacity within the stomach that is in close association with additional irregular metal opacity). The dog does have spondylosis deformans, which is a very common and incidental radiographic finding in older dogs. Although these changes are present, they are not the most clinically important findings on these radiographs.

Answer 60

Answer: **Atrial septal defect with systemic hypertension** Explanation The correct answer is atrial septal defect with systemic hypertension. This dog's polycythemia developed due to shunting of venous blood into the arterial circulation (aka right-to-left shunting) leading to hypoxemia and an increased drive for erythropoiesis and secondary polycythemia. This can be caused by any of the other 3 answer choices. An atrial septal defect with systemic hypertension results in oxygenated blood shunting into the venous circulation or left-to-right shunting, which usually does not cause hypoxemia

Answer 61

Answer: **Atrial septal defect with systemic hypertension** Explanation The correct answer is atrial septal defect with systemic hypertension. This dog's polycythemia developed due to shunting of venous blood into the arterial circulation (aka right-to-left shunting) leading to hypoxemia and an increased drive for erythropoiesis and secondary polycythemia. This can be caused by any of the other 3 answer choices. An atrial septal defect with systemic hypertension results in oxygenated blood shunting into the venous circulation or left-to-right shunting, which usually does not cause hypoxemia

Answer 62

Answer: **Development of organ mineralization** Explanation The correct answer is development of tissue mineralization. Cholecalciferol (Vitamin D3) acts by becoming converted to calcitriol and increases calcium and phosphorus levels leading to mineralization of organs, especially the kidneys. For the PowerPage on this topic, view Rodenticide Toxicity

Answer 63

Answer: **Prolene** Explanation The correct answer is prolene. Prolene is a monofilament non-absorbable suture which retains great tensile strength. This type of suture along with nylon suture is usually used on skin. PDS is a monofilament suture which is degraded by hydrolysis. Absorption is complete in approximately 182 days, and it retains tensile strength for 28-56 days. Dexon is a braided, multifilament, absorbable suture which is absorbed by hydrolysis in 100-120 days. Tensile strength is lost in 7-14 days. Catgut is broken down by phagocytosis and retains tensile strength for 14-28 days. Maxon is absorbed by hydrolysis starting at day 60 and completely absorbed by 6 months. Tensile strength is retained for about 21 days. ***PowerPage: Suture Materials

Answer 64

Answer: **Pasteurella multocida** Explanation The correct answer is Pasteurella multocida. This is a common cause of infectious disease in rabbits and is the causative agent of "snuffles". Of the choices listed, Pasteurella is the only respiratory pathogen. The upper respiratory syndrome is the most common presentation for Pasteurella in rabbits, but it can affect many other systems and can cause enzootic pneumonia, otitis media/interna, conjunctivitis, meningitis, encephalitis, reproductive tract infections, abscesses, and septicemia.

Answer 65

Answer: **Introduction of a new male** Explanation The correct answer is introduction of a new male. This induces sheep and goats to ovulate at the same time.

Answer 66

Answer: **Introduction of a new male** Explanation The correct answer is introduction of a new male. This induces sheep and goats to ovulate at the same time.

Answer 67

Answer: **Anuria** Explanation The correct answer is anuria. Hyperphosphatemia occurs in both acute and chronic renal failure. Anemia is seen in chronic renal failure due to decreased erythropoietin, shortened RBC lifespan, uremic inhibition of erythropoiesis, etc. Metabolic acidosis occurs in both acute and chronic renal failure from decreased bicarbonate production by the kidneys and from retention of metabolic acids.

Answer 68

Answer: **90L** Explanation The correct answer is 9OL. Total body water is 60% of body weight. Extracellular fluid is approximately 1/3 of total body water, therefore 450kg x .6 = 270L total body water 270L x .33 = 89.1L ECF. ECF is composed of plasma, interstitial fluid and transcellular lymph such as CS and synovial fluid.

Answer 69

Answer: **Pinnal-pedal reflex, clinical signs, superficial skin scrape** Explanation A superficial skin scrape is most useful. A deep skin scrape is used for Demodex mites, which reside in the hair follicles. Superficial skin scraping is indicated for Sarcoptic mange, since this mite lives in the stratum corneum. Pinnal-pedal reflex can be positive in 70% of Sarcoptic mange infestation but can also be positive in any dog with pruritus. Clinical signs are helpful because Sarcoptes typically infects the non-haired portions of the skin such as the ear pinnae, elbows, hocks, and ventral abdomen. If the mite is not found on skin scraping and you have clinical signs indicative of Sarcoptes then a therapeutic trial is warranted. Keep in mind that in most cases you will not be able to find the mite. A trichogram would not be indicated. This method can be used to diagnose dermatophytosis and sometimes Demodex. Histopathology will reveal a perivascular dermatitis that is non-specific. Rarely are the mites found on histopathology.

Answer 70

Answer: **Lateralization of signs and concurrent neurogenic muscle atrophy of the quadriceps and gluteal regions** Explanation With EPM, the important signs to remember are asymmetry, ataxia, and atrophy. Lateralization of the signs (asymmetry) and quadriceps and/or gluteal muscle atrophy are most consistent with EPM. Herpes myeloencephalitis is caused by EHV1 and often has an acute onset following an episode of fever, cough and nasal discharge or following abortions on a farm. This condition often affects more than one horse on a farm. The ataxia and weakness is usually symmetric. Cervical vertebral stenotic myelopathy (CVM) and equine degenerative myeloencephalopathy typically cause symmetric signs with the hindlimbs usually a grade worse than the forelimbs. The signs of CVM may be worsened by flexing or hyperextending the neck. Polyneuritis equi is more common in mature horses and usually starts with hyperesthesia progressing to anesthesia. There is progressive paralysis of the tail, rectum, bladder and urethra leading to urine dribbling. Verminous myeloencephalitis is less common and the onset is usually sudden with rapid deterioration and death. ***PowerPage: Equine Protozoal Myeloencephalitis

Answer 71

Answer: **Amsinckia intermedia** Explanation The correct answer is Amsinckia intermedia. This plant (aka fiddleneck, fireweed, and tarweed) contains pyrrolizidine alkaloids. PAs are hepatotoxic and cause three classical liver lesions. Do you recall them? Megalocytosis, biliary duct hyperplasia, and fibrosis. As a result of liver damage, the liver will be unable to clear normal chlorophyll breakdown products such as phylloerythrin, which causes photosensitization secondary to liver damage. The other answer choices are primary photosensitizing agents. ***PowerLecture: Hepatic Disorders

Answer 72

Answer: **Culicoides** Explanation The correct answer is Culicoides. Culicoides hypersensitivity, also referred to as sweet itch, occurs due to allergy to the saliva of the gnat. It recurs seasonally in the warmer months and tends to worsen with age. Typically, horses are pruritic and develop lesions on the poll, mane, and tail from self trauma, although ventral midline dermatitis can occur as well. More chronically, scarring can occur. Treatment is to decrease exposure to the gnat and to treat with steroids. Habronemiasis is a condition where the larvae of the stomach worm migrate and emerge creating granulomatous lesions, usually around the eye, male genitalia, or lower extremities. Inside the granulomas, you can find dead larvae. Haematobia irritans is a bigger problem in cattle than horses (they reproduce in cow feces) but can affect horses, especially ones that are near cattle. It typically causes ventral midline dermatitis with wheals with a central crust that progress to alopecia and ulceration with fairly focal lesions, rather than more diffuse lesions caused by Culicoides. Onchocerca can cause dermatitis in the horse due to hypersensitivity to dying microfilariae. Lesions include alopecia and scaling of the ventral midline, face, and pectoral region. Often, lesions are diamond shaped and there may be a "bull's eye" lesion on top of the head. Onchocerca is nonseasonal, in contrast to Culicoides hypersensitivity, and variably pruritic. Ocular lesions can also occur with Onchocerca including uveitis, conjunctivitis, and keratitis. Lastly, Hypoderma is also a bigger problem in cattle but can occur in horses and typically creates nodules on the dorsum that have a pore on top.

Answer 73

Answer: **Vestibular disease** Explanation These signs are compatible with mild infectious vestibular disease caused by bacterial otitis media/interna. Other possible causes of vestibular disease are guttural pouch mycosis, polyneuritis equi, viral labyrinthitis, and traumatic skull fractures.

Answer 74

Answer: **Oleander ingestion** Explanation The correct answer is oleander ingestion. Oleander contains a cardiac glycoside and will kill a horse by causing arrhythmias and stopping the heart. Anorexia and hemolysis cause a prehepatic icterus. Theiler's disease is an acute, diffuse, necrotizing hepatitis that occurs after receiving serum products and can cause a hepatic icterus. Tyzzer's disease is caused by Clostridium piliformis and can cause a hepatic icterus. ***PowerLecture: Hepatobiliary Disorders

Answer 75

Answer: **Triple pelvic osteotomies should only be performed in dogs free of radiographic signs of degenerative joint disease** Explanation Triple pelvic osteotomies (TPO) are designed to increase the dorsal coverage of the femoral head. If there are degenerative changes at the time of surgery then the likelihood of achieving good results with the procedure is diminished. This is why this surgery is typically performed in dogs that are 6mo - lyr of age. TPOs will not eliminate the progression of arthritis; however, it is believed that the degree of arthritis will be less and that many patients are clinically sound despite having radiographic evidence of arthritis. Total hip replacements (THR) can be performed as soon as the physes in the region have finished their growth. THRs have been performed in dogs as young as 1 year of age and sometimes even younger. A caudoventral luxation can occasionally occur with a total hip replacement; however, craniodorsal luxations are a much more common.

Answer 76

Answer: **Life long therapy is necessary, and control is often successful** Explanation Ravenous appetite with weight loss, hyperactivity, heart murmur, and high blood pressure would most likely indicate hyperthyroidism; especially in an older cat. Medical management can be successful with methimazole daily for the rest of the cat's life. Other treatment options include surgical thyroidectomy (not recommended since surgery can induce hypothyroidism) or radioactive iodine therapy. Hill's Y/D food has limited iodine, strict dietary management is required for any chance of success if using the Y/D as the treatment choice. It is important to screen and rescreen for renal disease prior to and after starting methimazole. Hyperthyroidism can mask renal disease due to increased blood pressure and blood flow through the kidneys leading to increased glomerular filtration rate. Owner must be warned that even if no signs are seen prior to initiating treatment, renal disease may be diagnosed at a later time. ### Feline Hyperthyroidism: Comprehensive Veterinary Guide **Definition:** Feline hyperthyroidism (FHT) is a common endocrine disorder in older cats caused by excessive production of thyroid hormones (thyroxine [T4] and triiodothyronine [T3]), usually due to thyroid adenomas or hyperplasia. **Causative Agents:** - **Primary Causes:** Thyroid adenomas or adenomatous hyperplasia. - **Environmental Factors:** Exposure to certain chemicals like bisphenol A and phthalates, iodine content in diet, and possibly genetic predisposition. **Pathophysiology:** - **Thyroid Hormone Overproduction:** Leads to an increased metabolic rate. - **Systemic Effects:** Hyperthyroidism affects multiple organ systems, causing metabolic, cardiovascular, and gastrointestinal disturbances. **Symptoms:** - Weight loss despite increased appetite - Polyuria, polydipsia - Increased vocalization, hyperactivity - Vomiting, diarrhea - Tachycardia, tachypnea - Unkempt hair coat **Clinical Changes:** - **Physical Examination:** Palpable thyroid nodule, weight loss, muscle wasting, heart murmurs, arrhythmias. - **Laboratory Findings:** Elevated total T4, sometimes with increased ALT and alkaline phosphatase. **Diagnosis:** 1. **Clinical Examination:** Detailed history and physical examination. 2. **Laboratory Tests:** - **Total T4 Measurement:** Primary diagnostic test. Elevated levels confirm hyperthyroidism. - **Free T4 by Equilibrium Dialysis (fT4ed):** Used when T4 levels are borderline. - **Thyroid Stimulating Hormone (TSH):** Low TSH supports the diagnosis of hyperthyroidism. 3. **Imaging:** - **Thyroid Scintigraphy:** Evaluates functional thyroid tissue and confirms the diagnosis. - **Additional Imaging:** Chest radiographs and echocardiography to assess cardiac involvement. **Treatment:** 1. **Radioactive Iodine (I-131):** - **Mechanism:** Selectively destroys hyperactive thyroid tissue. - **Administration:** Single injection or oral capsule. - **Advantages:** High cure rate (>95%), minimal side effects, treats ectopic thyroid tissue. - **Disadvantages:** Requires special facilities, isolation post-treatment. 2. **Medical Therapy:** - **Methimazole:** Inhibits thyroid hormone synthesis. - **Dosage:** 1.25-2.5 mg/cat twice daily, adjusted based on response. - **Forms:** Oral and transdermal. - **Side Effects:** Gastrointestinal upset, facial pruritus, hepatopathy, blood dyscrasias. - **Carbimazole:** Metabolizes to methimazole, similar mechanism and side effects. 3. **Surgical Thyroidectomy:** - **Indication:** When radioactive iodine is not an option. - **Procedure:** Unilateral or bilateral removal of thyroid glands. - **Complications:** Hypocalcemia, recurrence, anesthetic risks. 4. **Dietary Therapy:** - **Iodine-Restricted Diet:** Controls thyroid hormone production by limiting dietary iodine. - **Effectiveness:** 75-83% success rate in reducing T4 levels and clinical signs. **Monitoring:** - **Initial Follow-Up:** 2-4 weeks after starting treatment. - **Long-Term Monitoring:** Every 4-6 months for stable cases. - **Parameters:** T4 levels, CBC, chemistry panel, urinalysis, and blood pressure. **Prognosis:** - **General Outcome:** Good with appropriate treatment. Median survival up to 5.3 years for non-azotemic cats. - **Complications:** Untreated hyperthyroidism can lead to significant morbidity and mortality. **Summary:** Feline hyperthyroidism requires a systematic approach to diagnosis, including clinical signs, laboratory tests, and imaging. Treatment options include radioactive iodine, medical therapy, surgical thyroidectomy, and dietary management. Regular monitoring is crucial to manage the disease and any concurrent conditions effectively. For more detailed information, refer to the full PDF document.

Answer 77

Answer: **Coliform mastitis** Explanation This is a case of severe acute coliform mastitis, and the absorbed endotoxin (LPS) is causing many of the systemic signs observed. The cow needs to be aggressively treated with IV fluids, NSAIDS, and supportive nursing. The gland should be frequently milked out. The use of both intramammary and systemic antimicrobial drugs to which most coliforms are susceptible is still controversial, but is often done in cows in a severe state of illness as in this case. While this cow may have secondary hypocalcemia, treatment with calcium needs to be approached cautiously, as endotoxic animals have very sensitive myocardium and arrest may occur if calcium is given IV. If given, preferred routes of calcium administration would be subcutaneous or oral. ### Coliform Mastitis in Cattle: Comprehensive Veterinary Guide **Definition:** Coliform mastitis is a form of mastitis in dairy cattle caused by gram-negative, lactose-fermenting bacteria, primarily Escherichia coli, Klebsiella spp., and Enterobacter spp. **Pathophysiology:** - **Invasion:** Bacteria enter through the teat canal, proliferate in the mammary gland, and release endotoxins. - **Immune Response:** Endotoxins trigger an acute inflammatory response, characterized by neutrophil influx and cytokine release. - **Systemic Effects:** Severe cases can lead to systemic toxemia, including fever, shock, and even death. **Causes:** - **Environmental Factors:** Contaminated bedding, water, and equipment; poor milking hygiene; and trauma to the teats. - **Specific Pathogens:** E. coli and Klebsiella are common environmental pathogens associated with coliform mastitis. **Symptoms:** - **Local:** Swollen, firm udder, with watery, bloody, or pus-laden milk. - **Systemic:** Fever, anorexia, dehydration, and in severe cases, shock. **Clinical Changes:** - **Milk Changes:** Reduced milk yield, abnormal milk appearance (watery or containing clots). - **Udder Changes:** Swelling, heat, and pain in the affected quarter(s). **Assessment:** - **Clinical Signs:** Observation of milk and udder condition, systemic symptoms. - **Laboratory Tests:** Somatic cell count (SCC) in milk, bacterial culture to identify the causative agent. **Treatment:** - **Antibiotics:** Systemic and intramammary antibiotics, ideally chosen based on sensitivity testing. - **Cephalosporins:** Commonly used due to efficacy against gram-negative bacteria. - **Aminoglycosides and Fluoroquinolones:** Used for severe cases but require careful monitoring for residues in milk. - **Supportive Care:** Fluid therapy to manage dehydration and shock, anti-inflammatory drugs to reduce fever and pain. **Prevention:** - **Hygiene:** Proper milking procedures, clean and dry bedding, regular equipment maintenance. - **Teat Care:** Use of post-milking teat dips to reduce bacterial colonization. - **Vaccination:** Some vaccines are available for prevention against E. coli and Klebsiella spp. **Prognosis:** - **Severity:** Varies based on the extent of infection and timeliness of treatment. - **Outcomes:** Potential for chronic infections, reduced milk production, and, in severe cases, death or culling. **Epidemiology:** - **Incidence:** Higher in herds with poor environmental management; outbreaks can occur in warmer climates or with improper bedding materials. - **Zoonotic Risk:** Although rare, some coliform bacteria can be zoonotic, posing a risk to humans. **Key Points:** - **Early Detection:** Critical for effective treatment; regular monitoring of SCC and milk quality is essential. - **Veterinary Involvement:** Regular herd health assessments and consultations for mastitis management and antibiotic stewardship. For more detailed information, visit the [Merck Veterinary Manual](https://www.merckvetmanual.com/reproductive-system/mastitis-in-large-animals/mastitis-in-cattle).

Answer 78

Answer: **Compare pleural fluid triglyceride level to serum triglyceride levels** Explanation The pleural fluid obtained has a milky white appearance as a result of its high triglyceride content. Any patient that has an effusion triglyceride content higher than that of the serum is considered to have a chylothorax. Chyle is lymphatic fluid which contains a high quantity of fat. Abnormal flow or pressures in the thoracic duct are thought to cause exudation of chyle from lymphatic vessels into the thorax. The presence of chylomicrons in the sample, a cholesterol content greater than or equal to that of the serum, and a positive ether clearance test are also supportive chylothorax. Chylous fluid is typically white to pink in color, opaque and can have a variable specific gravity (1.019-1.050 in the cat). The protein level is variable (2.6-10.3 g/dL) and the white blood cell count can be over 7,000 cells/ul. A decreased glucose compared to that of serum is consistent with an infectious etiology. Lactate elevations can be expected in any patient that is undergoing anaerobic metabolism and a difference in lactate levels between the chyle and serum is not diagnostic for chylothorax. Alkaline phosphatase levels will not help in the diagnosis of chylothorax. In cats, the Siamese and Himalayans are predisposed.

Answer 79

Answer: **Lance tympanic membranes to drain material and begin supplementation of vitamin A** Explanation The correct answer is to lance the tympanic membranes and begin supplementing with vitamin A. Accumulations in the ear due to squamous metaplasia and secondary infection can result from vitamin A deficiency. The best thing to do is start systemic antibiotics, drain the ears, and provide appropriate nutrition.

Answer 80

Answer: **Corynebacterium pseudotuberculosis** Explanation The correct answer is Corynebacterium pseudotuberculosis. This is a classic description of how caseous lymphadenitis presents in sheep. Infection may occur via penetration through superficial skin wounds and sometimes through unbroken skin. The pus contains large numbers of bacteria that can survive for months in the environment and be a source of infection. Typical clinical signs are a slowly growing, non-painful mass at the point of entry or a local lymph node. Treatment is usually not attempted as this tends to be a chronic recurring disease causing economic loss. Carriers can be a source of infection to other animals. ***PowerPage: Top 10 Sheep and Goat Diseases ***PowerLecture: Caseous Lymphadenitis ### Key Information on Caseous Lymphadenitis (CL) in Sheep and Goats #### Etiology and Pathogenesis - **Causative Agent**: Corynebacterium pseudotuberculosis - **Transmission**: Through skin wounds, environmental contamination, and respiratory secretions - **Pathogenesis**: Bacteria enter through skin or mucous membranes, travel to lymph nodes, and form encapsulated abscesses. #### Clinical Findings - **External Form**: Abscesses in peripheral lymph nodes (e.g., submandibular, prescapular, prefemoral) - **Internal Form**: Chronic weight loss, respiratory signs (cough, nasal discharge) #### Diagnosis - **Definitive Diagnosis**: Culture of purulent material - **Serologic Tests**: Detect antibodies, but interpretation requires caution #### Treatment - **Management**: Culling, antimicrobial therapy (intralesional and systemic), abscess drainage and isolation - **Antibiotics**: Penicillin, rifampin, tulathromycin, oxytetracycline #### Control and Prevention - **Biosecurity**: Strict hygiene, disinfection, and isolation of affected animals - **Vaccination**: Species-specific vaccines - **Quarantine**: New animals should be tested and isolated before introduction to the herd For more detailed information, visit the [Merck Veterinary Manual](https://www.merckvetmanual.com/circulatory-system/lymphadenitis-and-lymphangitis-of-large-animals/caseous-lymphadenitis-of-sheep-and-goats?autoredirectid=22709).

Answer 81

Answer: **Type 1 vagal indigestion (free gas bloat)** Explanation Free gas bloat in young animals is often secondary to bacterial bronchopneumonia, and mediastinal lymph node inflammation that affects the thoracic vagus nerve. Once the gas accumulates, it stops motility and decreases appetite. Treat the pneumonia with antimicrobials. The gas can also be relieved by creating a small temporary rumen fistula. ***PowerLecture: Vagal Indigestion

Answer 82

Answer: **Feet and legs** Explanation Rapid growth is associated with limb and foot lesions in broilers.

Answer 83

Answer: **Feline immunodeficiency virus** Explanation The correct answer is feline immunodeficiency virus. The virus is shed in the saliva and is transmitted mainly through bites. The disease mostly affects older, outdoor male cats which have a higher likelihood of getting into fights and being bitten by other cats. Having the disease makes them immunosuppressed and more susceptible to infections. The remainder of the answer choices can be passed via passive contact. ### Comprehensive NAVLE Study Guide: Feline Immunodeficiency Virus (FIV) #### **Definitions and Etiology** - **Feline Immunodeficiency Virus (FIV)**: A lentivirus, similar to HIV, causing an acquired immunodeficiency syndrome in cats. - **Causative Agent**: FIV, a member of the retrovirus family, primarily affecting domestic cats. #### **Pathophysiology** - **Cell Tropism**: FIV replicates in CD4+ and CD8+ lymphocytes, macrophages, astrocytes, and microglial cells. Over time, FIV leads to immunosuppression, resulting in increased susceptibility to infections. - **Immune Response**: Initial immune response includes neutralizing antibodies and a cellular immune reaction. However, a latent infection arises, where viral replication continues at low levels, leading to a gradual decline in immune function. CD4+ cell counts decrease, and CD8+ cells increase, disrupting the CD4:CD8 ratio. #### **Clinical Signs** - **Stages of Infection**: 1. **Acute Phase**: Fever, lethargy, lymphadenopathy, and neutropenia. This stage may last weeks to months. 2. **Asymptomatic Phase**: The cat appears healthy but harbors the virus. This stage can last years. 3. **Chronic Clinical Signs**: Weight loss, persistent fever, anemia, leukopenia, stomatitis, behavioral changes, and recurrent infections. 4. **Terminal AIDS-Like Phase**: Severe immunosuppression, opportunistic infections, neoplasia, and neurological abnormalities. #### **Diagnosis** - **Antibody Testing**: ELISA and Western blotting are the primary diagnostic tools, detecting antibodies against FIV. False positives may occur in low-prevalence areas, necessitating confirmatory testing. - **Virus Isolation**: Not practical for routine diagnosis but can be done via blood cell culture. #### **Treatment** - **Antiviral Therapy**: - **AZT (Zidovudine)**: Inhibits viral replication, improves immune function, and prolongs life expectancy. Dosage: 5 mg/kg orally or subcutaneously twice daily. - **Other Antiviral Agents**: PMEA, D4T, and others have shown potential in vitro but are not widely available for clinical use. - **Symptomatic Management**: Treatment of secondary infections, supportive care, and regular monitoring of blood cell counts. #### **Prevention** - **Risk Mitigation**: Prevent exposure to FIV by keeping cats indoors, neutering them, and avoiding contact with infected or unknown cats. #### **Prognosis** - **Variable**: Depends on the stage of the disease at diagnosis and response to treatment. Some cats may live for years with minimal clinical signs, while others may progress rapidly to severe immunosuppression and associated complications. This detailed guide outlines the critical aspects of FIV, focusing on diagnosis, treatment, and management strategies essential for the NAVLE exam.

Answer 84

Answer: **Cutaneous xanthomatosis** Explanation Cutaneous xanthomatosis is a unique condition of birds caused by excessive accumulation of lipids in the skin. It is a macrophagic inflammatory response, with multinucleated giant cells and cholesterol crystals observed cytologically. A xanthoma is a benign growth and is most prevalent in cockatiels, budgies and cockatoos. They are typically non-aggressive, but at times can become locally invasive causing irritation and self-mutilation of the site. The etiology is unknown but a high fat diet and inactivity may contribute. Gout is a build-up of uric acid, and typically causes swollen painful joints. Bacterial dermatitis is usually associated with a heterophilic or mixed inflammation. Poxvirus lesions have clusters of squamous epithelial cells with eosinophilic cytoplasmic vacuoles. Cutaneous lymphoma yields highly cellular samples of immature lymphocytes.

Answer 85

Answer: **Confine pet and observe for 10 days** Explanation The correct answer is to confine and observe the cat for 10 days. You would only need to euthanize and test if the cat is a stray. If the cat was not up to date on vaccinations, you would either euthanize and test, or quarantine for 10 days in an approved facility.

Answer 86

Answer: **Surgical decompression and biliary-to-intestinal diversion (cholecystoduodenostomy or cholecystojejunostomy) after stabilizing the patient with appropriate supportive care and fluid therapy** Explanation The case described is acute cholangiohepatitis secondary to complete biliary obstruction from a cholelith. Surgical decompression is indicated when discrete choleliths are seen or complete biliary obstruction is identified. In this case, there are both. If this had been a more typical case of cholangiohepatitis without choleliths or complete biliary obstruction, the treatment of choice would be supportive care and fluid therapy plus treatment with ampicillin, metronidazole, ursodeoxycholic acid. Choleliths are relatively rare in dogs and cats compared to humans but are seen sporadically.

Answer 87

Answer: **The practice** Explanation Radiographs are part of the patient's medical record and belong to the practice where they were taken and must be kept for a specified period of time depending on state laws.

Answer 88

Answer: **Anaplasma phagocytophilum** Explanation The correct answer is Anaplasma phagocytophilum (previously known as Ehrlichia equi). Anaplasma phagocytophilum infection can cause morulae to be present in neutrophils and eosinophils. Neorickettsia ristici (Potomac horse fever) can cause morulae in monocytes but these are rarely seen on blood smears. Borrelia organisms are not seen in peripheral blood and herpes inclusion bodies are intranuclear and would not be seen in a blood smear.

Answer 89

Answer: **The parasite causes hydatid cyst disease in humans, which can be fatal** Explanation The correct answer is the parasite causes hydatid cyst disease in humans, which can be fatal. Echinococcus granulosus is the hydatid tapeworm which is non-pathogenic in dogs but is highly pathogenic to fatal in humans and other intermediate hosts in which a hydatid cyst forms. The infection is acquired in dogs by eating raw sheep meat or viscera infected with the parasite. All dogs suspected of being infected should be treated with praziquantel. More information about Cestodes can be found in the PowerPage called, "Selected Parasites of Small Animal Species: Cestodes." ***PowerPage: Selected Parasites of Small Animal Species: Cestodes

Answer 90

Answer: **Mannheimia hemolytica** Explanation The correct answer is *Mannheimia hemolytica*, formerly called **Pasteurella hemolytica**. Mannheimia pneumonia is the most common infectious bacterial disease of sheep and goats. Most cases are caused by M. hemolytica type A. A variety of predisposing factors are suspected. Clinical signs include fever, depression, mucopurulent nasal discharge, coughing, pulmonary crackles and wheezes, and tachypnea. Necropsy lesions are fibrinopurulent pleuropneumonia. Pasteurella multocida is also a cause of pneumonia in sheep and goats. P pneumoniae is a made up name.

Answer 91

Answer: **Campylobacter** Explanation *Campylobacter* infection (or vibriosis) is the most significant cause of abortion in sheep in North America. C jejuni is the most common and C. fetus is the other main cause of abortion. Other common causes are Toxoplasma and Chlamydia psittaci. Bluetongue is much less common. Brucella ovis rarely causes abortion in sheep although it does cause epididymitis. Sheep are not very susceptible to abortion from leptospirosis. Q fever, or Coxiella burnetii, is an uncommon cause of abortion and is more of concern due to zoonotic potential.

Answer 92

Answer: **Was the dog vaccinated recently?** Explanation This puppy likely has hypertrophic osteodystrophy (HOD). Weimaraners are predisposed and litter-mates will commonly be affected. Although the exact cause is unknown, the leading hypothesis is recent vaccination leading to hyper-reactivity of the immune system. In a study of 53 Weimaraners with HOD, all had been vaccinated within the past 30 days. Trauma resulting in a fracture or septic arthritis is untreatable with steroids. A snake or spider bite can cause a large amount of swelling but resolution with oral steroids alone may not be enough. Fungal disease can cause bony changes as well but if the litter-mate was affected by the same disease process, steroids should have worsened the disease.

Answer 93

Answer: **Polioencephalomalacia** Explanation The correct answer is polioencephalomalacia (thiamine deficiency). This most commonly occurs in lambs being fed diets that are high in concentrates or molasses such as horse feed. This occurs because in normal lambs, ruminal bacteria produce sufficient thiamine to meet their requirements. Excess feeding of concentrates leads to ruminal acidosis, decreases the population of thiamine-producing bacteria, and increases production and activity of ruminal thiaminase. Other causes of polioencephalomalacia are bracken fern ingestion due to thiaminase in the plant, overdose of amprolium which is a thiamine analog, and high dietary sulfate. Clinical signs include cortical blindness, head pressing, and incoordination progressing to recumbency, opisthotonos and convulsions. Treatment is with thiamine replacement. Diagnosis is usually based on clinical signs and necropsy findings, but blood thiamine levels and erythrocyte transketolase activity can be measured. Classic necropsy lesions are a soft, edematous cerebral cortex with gray-yellow discoloration and flattened gyri. ***PowerPage: Top 10 Sheep and Goat Diseases

Answer 94

Answer: **Polioencephalomalacia** Explanation The correct answer is polioencephalomalacia (thiamine deficiency). This most commonly occurs in lambs being fed diets that are high in concentrates or molasses such as horse feed. This occurs because in normal lambs, ruminal bacteria produce sufficient thiamine to meet their requirements. Excess feeding of concentrates leads to ruminal acidosis, decreases the population of thiamine-producing bacteria, and increases production and activity of ruminal thiaminase. Other causes of polioencephalomalacia are bracken fern ingestion due to thiaminase in the plant, overdose of amprolium which is a thiamine analog, and high dietary sulfate. Clinical signs include cortical blindness, head pressing, and incoordination progressing to recumbency, opisthotonos and convulsions. Treatment is with thiamine replacement. Diagnosis is usually based on clinical signs and necropsy findings, but blood thiamine levels and erythrocyte transketolase activity can be measured. Classic necropsy lesions are a soft, edematous cerebral cortex with gray-yellow discoloration and flattened gyri. ***PowerPage: Top 10 Sheep and Goat Diseases

Answer 95

Answer: **Glabders** Explanation The horse's presentation is also consistent with the nasal form of glanders. Glanders is a bacterial disease caused by Burkholderia mallei (previously known as Pseudomonas mallei). It is thought to be endemic in regions of the Middle East, Asia, Africa, and South America. In addition to horses, glanders can be seen in donkeys, mules, and small ruminants. Glanders is primarily a concern in horses because they can be chronic or occult carriers that intermittently shed this deadly and potential zoonotic pathogen. Burkholderia mallei causes 3 different forms of disease; nasal glanders, pulmonary glanders, and cutaneous glanders (also referred to as Farcy). The nasal form presents with high fever, loss of appetite and labored breathing with cough. Viscous mucopurulent discharge or crusting may be present around the nares. There may be ulceration of the upper respiratory passages that resolve in the form of star-shaped cicatrices ("stellate scars"). Regional lymph nodes may be enlarged and indurated and may rupture or adhere to deeper tissues. The pulmonary form often develops over several months, beginning as a fever with dyspnea and cough. Lung lesions commence as light colored nodules surrounded by hemorrhage or as diffuse pneumonia. The nodules may become caseous or calcified and discharge contents to the upper respiratory tract. Nodules may also be found in other organs. The cutaneous form develops over several months, beginning with cough and dyspnea as well. Eventually, nodules develop in subcutaneous tissue along the course of the lymphatics of the legs, costal areas, and ventrum. They can rupture and excrete infectious purulent exudate. Infected lymphatics may form thickened cord-like lesions that sometimes coalesce into a string of beads appearance known as "farcy pipes". Nodular lesions of other organs may also be found. Burkholderia mallei can be identified in smears made from fresh lesions as mainly extracellular straight Gram-negative rods with rounded ends. Several diagnostic tests exist including PCR, ELISA, and Western Blot but the two that you actually need to know about because they are used in international trade are complement fixation (CF) serology and the mallein test. The mallein test is considered the most reliable, sensitive, and specific test; it involves injection of mallein purified protein derivative intradermally into the lower eyelid. The test is read at 24 and 48 hours and a positive reaction is characterized by edematous swelling or purulent discharge. Horses should not be treated; local authorities should be notified if a case is suspect and if disease is confirmed, horses must be humanely destroyed and affected carcasses should be burned and buried. Dourine is a trypanosomal venereal disease. Surra is a trypanosomal disease causing primarily fever, weakness, and lethargy. Rift Valley Fever is a viral disease primarily of ruminants causing influenza-like signs and hepatic lesions. African Horse Sickness is a viral respiratory disease of horses but signs are primarily pulmonary whereas the horse in this case has nasal signs and mandibular lymph node enlargement.

Answer 96

Answer: **Fleas/flea dirt** Explanation Adult fleas contain the cysticercoid life stage of the common tapeworm Dipylidium caninum. As cats groom themselves, they ingest the adult flea; the tapeworm then develops into its adult form in the intestines. It is a common myth that cats won't get fleas or intestinal parasites if they are indoors-only. While these patients are at a decreased risk, they still can become infected/infested with the right exposure.

Answer 97

Answer: **Intestinal impaction** Explanation This is an image of a Parascaris equorum egg. It is almost spherical in shape with a brown color and contains a single-celled zygote. In foals, a significant ascarid burden with Parascaris equorum can lead to intestinal impaction and associated colic. Thrombosis of the mesenteric artery occurs with Strongylus vulgaris infestations. Immune mediated hypersensitivities may occur in adult horses with Parascaris equorum infestations but is unlikely to be a significant cause of the morbidity seen in foals. Larval migration can occur with Parascaris equorum but typically will affect the lungs or liver and this stage of the parasite does not lead to colic. Enteroliths are not caused by gastrointestinal parasitism.

Answer 98

Answer: **Intestinal impaction** Explanation This is an image of a Parascaris equorum egg. It is almost spherical in shape with a brown color and contains a single-celled zygote. In foals, a significant ascarid burden with Parascaris equorum can lead to intestinal impaction and associated colic. Thrombosis of the mesenteric artery occurs with Strongylus vulgaris infestations. Immune mediated hypersensitivities may occur in adult horses with Parascaris equorum infestations but is unlikely to be a significant cause of the morbidity seen in foals. Larval migration can occur with Parascaris equorum but typically will affect the lungs or liver and this stage of the parasite does not lead to colic. Enteroliths are not caused by gastrointestinal parasitism.

Answer 99

Answer: **Disruption of function of the plumage** Explanation Feathers serve a critical waterproofing and insulatory function which is disrupted by oil and can rapidly result in hypothermia. Other concerns for oiled birds include Gl irritation from ingestion of oil during preening, hemolytic anemia, and pneumonia due to inhalation of oil. Treatments include heat, supportive care, and activated charcoal. Once stabilized, frequent high pressure, warm, mild detergent baths and clean warm water rinses until water beads freely off of the feathers is important. Birds should be placed in warm air flow until dry and they should be maintained on self-skimming ponds for several days after washing to ensure full waterproofing.

Answer 100

Answer: **In-ovo vaccination** Explanation The disease described in this question is most consistent with Marek's disease. Marek's disease is a herpesvirus that causes neurologic signs, cutaneous signs, or visceral tumors. Key signs that should make you think of Marek's disease are: 1) Thickened nerves (vagus, brachial, and sciatic) 2) Paralysis of legs, wing, and/or neck 3) Gray iris or irregular pupils 4) Raised, rough skin around feather follicles 5) Gray foci of neoplastic tissue in liver, spleen, kidney, lungs, heart, and muscle Diagnosis is usually based on some combination of these findings. The disease is extremely widespread and infectious in flocks worldwide and there is no effective treatment. Vaccination is the key to the prevention and control of Marek's disease. Additionally, improved hygiene and/or an all-in/all-out production strategy can be helpful. There are many different specific types of vaccines (against different serotypes/strains) available but it is unlikely that you would be asked about those details on a board exam. Vaccination strategies and management of young animals is important though because there is a window of weeks before vaccines administered at hatching can provide protective immunity. In-ovo vaccination is now used in commercial broiler chickens because it can be performed via automated machines with precision and reduces labor costs.

Answer 101

Answer: **In-ovo vaccination** Explanation The disease described in this question is most consistent with Marek's disease. Marek's disease is a herpesvirus that causes neurologic signs, cutaneous signs, or visceral tumors. Key signs that should make you think of Marek's disease are: 1) Thickened nerves (vagus, brachial, and sciatic) 2) Paralysis of legs, wing, and/or neck 3) Gray iris or irregular pupils 4) Raised, rough skin around feather follicles 5) Gray foci of neoplastic tissue in liver, spleen, kidney, lungs, heart, and muscle Diagnosis is usually based on some combination of these findings. The disease is extremely widespread and infectious in flocks worldwide and there is no effective treatment. Vaccination is the key to the prevention and control of Marek's disease. Additionally, improved hygiene and/or an all-in/all-out production strategy can be helpful. There are many different specific types of vaccines (against different serotypes/strains) available but it is unlikely that you would be asked about those details on a board exam. Vaccination strategies and management of young animals is important though because there is a window of weeks before vaccines administered at hatching can provide protective immunity. In-ovo vaccination is now used in commercial broiler chickens because it can be performed via automated machines with precision and reduces labor costs.

Answer 102

Answer: **Enrofloxacin** Explanation You should be suspicious for prostatitis in this patient. Your antibiotic choice should be based on culture and sensitivity results, but because your patient is sick you will want to start an antibiotic that has good penetration of the prostate until the culture results are back. Chloramphenicol, erythromycin, trimethoprim and fluoroquinolones are able to pass the blood-prostate barrier. Cephalexin and cefpodoxime are cephalosporins and may be effective if the blood-prostate barrier is disrupted, but they would not be the first choice.

Answer 103

Answer: **Discoid lupus erythematosus** Explanation Discoid lupus (along with Pemphigus foliaceus) are autoimmune conditions that can result in ulcerative nasal dermatitis and loss of cobblestone appearance. Dermatophytosis (ringworm) often affects the muzzle. However, it rarely affects the nasal planum, because dermatophytes live in hair follicles and there are no hair follicles on the nasal planum. (This is also why it would not be folliculitis). Zinc-responsive dermatosis typically causes scaling and crusting but not usually erosions or ulcers. The next step for this dog would be to biopsy.

Answer 104

Answer: **These are most likely pulmonary contusions; your dog needs to be carefully monitored for the next day as they may worsen and lead to breathing problems** Explanation The correct answer is these are most likely pulmonary contusions; your dog needs to be carefully monitored for the next day as they may worsen and lead to breathing problems. Pulmonary contusions can cause respiratory deterioration in the apparently stable patient for up to 24 hours after trauma. They usually then improve over the next 24-48 hours. In this case, careful monitoring is probably indicated for 24 hours followed by recheck radiographs. These are indicated to detect possible abscesses, early pneumonia, cysts, or other related injuries.

Answer 105

Answer: **Ventricular septal defect** Explanation Congenital ventricular septal defect is one of the most commonly encountered congenital cardiac defects in cattle. It may be a relatively benign of cause death, depending on size. If the rancher sees several calves with this defect, he should discontinue using the bull responsible.

Answer 106

Answer: **Cerebellum** Explanation The correct answer is cerebellum. The cerebellum is responsible for the coordination and regulation of range, rate, and strength of movement along with balance and posture. Clinical signs associated with cerebellar disease include intention tremors, hypermetria, hypometria, and ataxia. Mentation will be normal if the disease is strictly confined to the cerebellum.

Answer 107

Answer: **Moraxella bovis** Explanation The correct answer is Moraxella bovis. Thelazia is the eye worm. Histophilus somni is a cause of many syndromes, but is rarely found in the eye. E. coli is not an ocular pathogen. ***PowerPage: Infectious Bovine Keratoconjunctivitis (Pinkeye)

Answer 108

Answer: **Concern about the number of animals lost when cats hunt** Explanation The impact on other animals is not a consideration for welfare as it relates to indoor cats.

Answer 109

Answer: **Medial transposition of the tibial tuberosity** Explanation The correct answer is medial transposition of the tibial tuberosity. If you have a medially luxating patella, you need to transpose the tibial tuberosity laterally in order to line up the patellar tendon with the rest of the stifle in an effort to reduce the likelihood of patellar luxation. The two most important procedures that reduce the incidence of recurrence are lateral transposition of the tibial tuberosity and modifying the trochlear groove of the femur. ***PowerLecture: Patellar Luxation

Answer 110

Answer: **Innervated by parasympathetic nervous system by cranial nerve Ill** Explanation The correct answer is that it is innervated by parasympathetic nervous system by cranial nerve Ill. The iris sphincter is stronger than the iris dilator. It receives parasympathetic innervation by cranial nerve Ill. It is comprised of smooth muscle in mammals, unlike birds, where it is striated. The innervation makes sense if you consider that when your sympathetic nervous system is activated, your eyes become dilated; that leaves the parasympathetic nervous system to constrict the pupil, which is the responsibility of the sphincter. ***PowerPage: Cranial Nerve Examination and Diseases

Answer 111

Answer: **Collagenolytic granuloma** Explanation The image and description are most consistent with a collagenolytic granuloma. Feline eosinophilic granuloma complex consists of 3 separate clinical syndromes: 1) The collagenolytic granuloma (also known as eosinophilic granuloma or linear granuloma) usually occurs on the nose, chin (as in this case), oral cavity, or caudal thighs. The lesions are typically raised and ulcerative or nodular as seen here. 2) The eosinophilic plaque occurs most frequently on the abdomen and medial thighs but can appear other places. They appear as single or multiple, raised, red, often ulcerated lesions of varying size (0.5-7 cm). They frequently have a cobblestone appearance and unlike eosinophilic ulcers, these are often pruritic. This condition is histopathologically similar to miliary dermatitis and is usually associated with underlying allergy. 3) The eosinophilic ulcer (also known as indolent ulcer) typically occurs on the upper lip and may be unilateral or bilateral. They often have a characteristic central area of yellow to pink tissue with a slightly raised circumferential edge The underlying cause of eosinophilic ulcers and collagenolytic granulomas are unknown, although an underlying allergic cause such as arthropod bites and/or cutaneous hypersensitivity have been suggested. Treatment of collagenolytic granulomas is also controversial so it is unlikely that you would be asked about treatment of this disorder on a board exam aside from knowing that you should attempt to identify and remove/treat underlying allergy or biting arthropod problems. Some cases respond to antibiotic therapy but most require glucocorticoid therapy.

Answer 112

Answer: **Type I Salter-Haris fracture of the distal femur l** Explanation Physeal fractures are commonly described in Salter-Harris nomenclature. In this system, a type I is a fracture through the physis, a type Il is fracture partway through the physis extending up into the metaphysis, a type Ill is a fracture partway through the physis extending down into the epiphysis, a type IV is a fracture through the metaphysis, physis, and epiphysis, and a type V is a crush injury to the physis

Answer 113

Answer: **Earthworm** Explanation Earthworms, slugs, and snails can serve as paratenic hosts, eventually being eaten by the chicken to transmit the infection. The gapeworm resides in the trachea and lungs of various birds (domestic or wild). Infection can happen directly by ingestion of infective eggs or larvae. Normally, significant field infection is due to ingestion of the transport host, which can include earthworms, snails, and arthropods.

Answer 114

Answer: **Abomasal torsion** Explanation The correct answer is abomasal torsion. The clinical signs described are classic for an abomasal torsion. These are much less common than left or right displaced abomasum. However, the risk factors for developing abomasal torsion appear to be the same. This finding is a surgical emergency and must be corrected before cows go into shock. Another factor is that many times you may be able to palpate abomasal torsion rectally, but not always (esp difficult in large Holstein cows). Cecal displacement and cecal volvulus can be ruled out because you would likely be able to palpate these disease processes via rectal examination as a soft loaf of bread that you can get all the way around. The ping is usually high in the right flank and does not extend to the 9th rib on a line from hip to elbow. Animals with intussusception are very colicky and have scant dark red feces. The intussusception can be found sometimes by rectal palpation as a firm painful mass. Gas in the spiral colon is a frequent finding in any sick cow with poor GI motility and is not a primary disease problem. It is diagnosed by finding an 8-inch circular ping high on the last rib or just behind it.

Answer 115

Answer: **Start aggressive IV fluid therapy and run a chemistry panel** Explanation The correct answer is start aggressive IV fluid therapy and run a chemistry panel. Addisonian patients often present in hypovolemic shock, so the first step to treating this dog is to restore vascular volume with IV fluids and to run a chemistry panel to check the extent of electrolyte abnormalities (hyponatremia, hyperkalemia, and elevated BUN). IV dexamethasone would not take precedence over restoring vascular volume, and subcutaneous fluid treatment is not aggressive enough for treatment of hypovolemia. Abdominal ultrasound would not be a priority in this case but could eventually be helpful in ruling in/out other differentials. Lysodren is used for treating hyperadrenocorticism. One possible complication of Lysodren treatment is to make a dog Addisonian, which often causes the animal to present with the signs described as in the question.

Answer 116

Answer: **Cephalexin for 8 weeks** Explanation Deep pyodermas involve tissues deeper than the epidermis, including the dermis and even subcutis. The skin may heal on the surface before the deeper infection is resolved; making clinical cure difficult to assess. In general, deep infections can require 6-8 weeks of antibiotic treatment (and even 12 weeks for severe cases) for resolution. Deep pyoderma can be secondary to allergies, skin fold anomalies, endocrine disorders, immune mediated skin diseases, bacterial and/or fungal skin infections, or migrating foreign bodies. Determining the underlying etiology will help with resolution and minimize chances of treatment failure and re-occurrence. Diagnostics should include skin scraping and impressions, culturing for bacteria and fungi, biopsy, and blood work. Treatments typically include antimicrobials that have demonstrated effectiveness, antifungals if needed, and frequent topical treatments with chlorhexidine shampoo and removal of the dead tissue and debris. Incidentally, the German Shepherds are predisposed to severe deep pyodermas that can be difficult to treat. Discussing this with your client will help give them realistic expectations for treatment. German Shepherds are at a higher risk of developing dry eye from Trimethoprim-sulfa; therefore, it is not recommended for this condition due to the length of time required to treat a deep pyoderma.

Answer 117

Answer: **Remove scabrous feeds** Explanation The bacteria causing lumpy jaw (Actinomyces bovis) is a normal inhabitant of the cow's oral cavity or rumen and causes disease when it is able to invade into damaged mucosa, most frequently caused by scabrous or prickly feed.

Answer 118

Answer: **0-4 day old foals** Explanation The correct answer is 0-4 day old foals. In utero, the foal is protected from the mare's antibodies due to epitheliochorial placentation (in humans, this condition occurs in utero). The foal takes in colostrum during its first 24 hours of life from the mare and develops the condition fairly acutely. Remember NI develops because the newborn foal expresses alloantigens on its red blood cells inherited from the sire that the mare does not have. If the mare becomes sensitized to the sire's specific antigen, maternal antibodies are produced and absorbed by the foal soon after birth. This subsequently results in lysis of the red blood cells. Pre-parturient blood testing between the mare and stallion may help in identifying the likelihood of this occurring. ***PowerPage: Neonatal soerythrolysis

Answer 119

Answer: **Eustachian tube** Explanation The correct answer is eustachian tube. This tube connects the pharynx and the inner ear. The semicircular canals are part of the inner ear. The canal of Schlemm is in the eye. The mandibular foramen is in the mandible, as the name implies. The cavernous sinus is a portion of the skull where the cranial nerves heading toward the eyes travel.

Answer 120

Answer: **Calcium deficiency** Explanation With seeds as a primary diet, many reproductively active females do not maintain adequate calcium levels to be able to lay eggs normally. This leads to weakened contractions of the reproductive tract and an inability to pass eggs through the oviduct. Initial therapy should consist of fluid support and calcium prior to attempt to reduce the prolapse. While vitamin A deficiency is often present in seed-eating birds, the clinical syndromes associated with this are more commonly squamous metaplasia affecting the oral mucosa, respiratory and renal systems. Hypercholesterolemia is often associated with seed-diets, but does not generally result in egg-binding or prolapse, as reproductively active birds will normally have elevated levels of cholesterol for egg production. Excessive amounts of oral calcium are generally not absorbed by the gastrointestinal tract and are excreted, making it difficult to over-supplement with oral calcium.

Answer 121

Answer: **It is legally required for veterinary practices to have it for full and part time employees** Explanation Worker's compensation insurance covers injuries sustained on the job. It is required in all states and is paid for by the practice.