General Questions - Final Coverage

Question 1

Which of the following statements about the pathogenesis of Dermatophilosis is FALSE?

A) D. congolensis zoospores are attracted to skin sites by the respiratory efflux of low concentrations of carbon dioxide.

B) Hyphae penetrate into the living epidermis, causing an acute inflammatory reaction.

C) Natural resistance to acute infection is primarily due to established immunity following initial exposure.

D) In chronic infections, wet scabs enhance the proliferation and release of zoospores from hyphae.

Answer 1

Natural resistance to acute infection is primarily due to established immunity following initial exposure.

Question 2

A sheep presents with matted wool, crusts, and exudates over its back and sides. Upon examination, the animal is painful but shows no signs of pruritus. These clinical signs are most consistent with:

Answer 2

Mycotic dermatitis

Question 3

In cattle, which stage of Dermatophilosis lesion progression is characterized by “hairs matted together as paintbrush lesions”?

Answer 3

Stage 1

Question 4

A dairy cow develops papular, crusted lesions on its udder. Which of the following predisposing factors is LEAST likely to be associated with this specific lesion distribution in Dermatophilosis?

A) Prolonged wetting of the skin due to standing in deep water.
B) Mechanical vectors like biting flies.
C) Tick infestation in the udder area.
D) Reduced or deficient normal skin barriers.

Answer 4

Mechanical vectors like biting flies.

Question 5

A group of goats is experiencing an outbreak of a highly contagious disease. Clinical signs include a sudden fever of 40.5 C, mucopurulent nasal discharge with a putrid odor, necrotic stomatitis affecting the lower lip and gum, and severe diarrhea. Post-mortem examination reveals “zebra-striped” appearance in the rectum and sloughed Peyer’s patches. These findings are pathognomonic for?

Answer 5

Peste des petits ruminants

Question 6

Regarding the lesions of Peste des petits ruminants (PPR), which of the following organs is least commonly and severely affected?

A) Abomasum
B) Large Intestine
C) Rumen
D) Peyer’s Patches

Answer 6

Rumen

Question 7

Which of the following is typically observed early in the clinical course of acute Peste des petits ruminants?
A) Profuse diarrhea leading to hypothermia and death.
B) Bronchopneumonia characterized by coughing.
C) Serous nasal discharge.
D) The development of the characteristic “zebra-striped” appearance in the rectum.

Answer 7

Serous nasal discharge

Question 8

In the pathogenesis of Bovine Spongiform Encephalopathy (BSE), after the agent crosses the mucosal barrier in the digestive tract, where does it primarily accumulate and replicate before infecting the enteric nervous system?

Answer 8

Gut-associated lymphoid tissues (GALT)

Question 9

A 4-year-old dairy cow exhibits subtle behavioral changes, including increased nervousness, difficulty negotiating obstacles, and reluctance to be milked. Over several weeks, these signs progress to include hypermetria and tremors. A definitive diagnosis would rely on characteristic lesions in the brain and spinal cord, specifically?

Answer 9

Neuronal vacuolation, degeneration and loss, and astrocytic hypertrophy and hyperplasia.

Question 10

Dairy cows were affected by BSE three times more often than beef cattle during the European outbreak. The most probable reason for this disparity, is?

Answer 10

Dairy cows were more likely to be fed animal-source protein supplements.

Question 11

What is the primary mechanism by which the Blue Tongue virus causes clinical disease in ruminants?

Answer 11

Endothelial damage, hemorrhage, vascular occlusion, and tissue edema.

Question 12

A sheep with Blue Tongue is suspected. What clinical signs, if observed, would be most indicative of a severe acute case?

Answer 12

Cyanotic and protruding tongue, torticollis, and abortion.

Question 13

Post-mortem examination of a sheep reveals distinctive hemorrhages at the base of the pulmonary artery, severe alveolar edema, and congestion of the hoof laminae. These lesions are highly suggestive of?

Answer 13

Blue Tongue

Question 14

A cattle farmer observes lesions on his herd primarily located on the head, ears, axillae, groin, and scrotum. Based on the pathogenesis of Dermatophilosis, which of the following predisposing factors is most likely responsible for initiating these specific lesions?

A) Prolonged periods standing in deep water and mud.
B) Mechanical transmission by biting flies.
C) Infestation by ticks.
D) Spiny plants causing abrasions.

Answer 14

Infestation by ticks.

Question 15

In chronic Dermatophilosis in sheep, the “lumpy wool” form is characterized by?

Answer 15

Pyramid-shaped masses of scab material bound to wool fibers, primarily on dorsal areas.

Question 16

A goat producer reports a sudden increase in body temperature in several young animals, accompanied by a dull coat, dry muzzle, and depressed appetite. The morbidity and mortality rates in this outbreak are observed to be exceptionally high, near 90%. Based on the provided information, which of the following statements about this scenario is TRUE?

A) The high morbidity and mortality are atypical for PPR.
B) The incubation period for this disease is likely less than 24 hours.
C) Older animals in the herd would likely show similar or even higher mortality rates.
D) The elevated morbidity and mortality rates are consistent with PPR, especially in young animals.

Answer 16

The elevated morbidity and mortality rates are consistent with PPR, especially in young animals.

Question 17

Which of the following is an expected post-mortem finding in a case of Peste des petits ruminants, particularly affecting the digestive tract?

A) Extensive involvement and severe lesions in the rumen and reticulum.
B) Regularly outlined erosions with red, raw floors oozing blood in the abomasum.
C) More severe lesions in the small intestines than in the large intestines.
D) Absence of any lymphoid tissue changes.

Answer 17

Regularly outlined erosions with red, raw floors oozing blood in the abomasum.

Question 18

The spread of the BSE agent from the gut-associated lymphoid tissues (GALT) to the brain primarily occurs via which pathway?

A) Hematogenous spread through the circulatory system, directly infecting the cerebral cortex.
B) Retrograde axonal transport through sensory neuronal pathways.
C) Efferent neuronal pathways (parasympathetic and sympathetic) originating from the enteric nervous system (ENS).
D) Direct invasion of the brain tissue from the nasal cavity.

Answer 18

Efferent neuronal pathways (parasympathetic and sympathetic) originating from the enteric nervous system (ENS).

Question 19

Classical BSE is most commonly diagnosed in cattle within which age range?

Answer 19

3-6 years old.

Question 20

A prominent clinical sign of acute Blue Tongue that distinguishes it from diseases primarily causing skin lesions or neurological signs is:

A) Painful, non-pruritic crusts on the dorsal midline.
B) Hyperesthesia and difficulty negotiating obstacles.
C) Cyanotic tongue and hyperaemia of the muzzle, lips, and face leading to oedema.
D) Necrotic stomatitis affecting the lower lip and gum.

Answer 20

Cyanotic tongue and hyperaemia of the muzzle, lips, and face leading to oedema.

Question 21

In fatal cases of Blue Tongue with pulmonary complications, what is a characteristic finding in the lungs?

Answer 21

Severe alveolar oedema and the bronchial tree filled with froth.

Question 22

Which of the following cells are directly involved in the systemic replication of the Blue Tongue virus, leading to the characteristic pathological changes?
A) Neurons and astrocytes.
B) M-cells and dendritic cells.
C) Phagocytic cells of the epidermis.
D) Hematopoietic cells and endothelial cells.

Answer 22

Hematopoietic cells and endothelial cells.

Question 23

Which of the following statements accurately describes the early pathogenesis of classical scrapie after oral ingestion of PrPsc?

A) PrPsc directly infects the brainstem and spinal cord, leading to immediate neurodegeneration.

B) PrPsc bypasses the gut-associated lymphoid tissue (GALT) and replicates exclusively in peripheral nerves.

C) PrPsc enters the palatine tonsil and crosses the intestinal wall, primarily accumulating in the GALT, with Peyer’s patches being a crucial entry point.

D) The lymphoid dissemination phase precedes the entry into the gut, as PrPsc is first absorbed into the bloodstream.

Answer 23

PrPsc enters the palatine tonsil and crosses the intestinal wall, primarily accumulating in the GALT, with Peyer’s patches being a crucial entry point.

Question 24

A 3-year-old sheep exhibits progressive neurological signs, including ataxia and hypersensitivity to stimuli. The owner also reports that the animal is frequently rubbing against fences and objects, causing wool loss. Based on these clinical signs, which form of scrapie is most likely?

Answer 24

Classical scrapie, given the age and presence of pruritus.

Question 25

Considering the pathogenesis of classical scrapie, why might older animals be less susceptible to initial prion entry via the oral route?

Answer 25

The amount of gut-associated lymphoid tissue (GALT) decreases with age, making prion entry less efficien

Question 26

Which of the following is the most consistent and definitive diagnostic method for classical scrapie, especially given the lack of specific gross lesions and variable clinical signs? A) Serological testing for anti-PrPsc antibodies. B) Gross necropsy examination for characteristic CNS lesions. C) Postmortem microscopic tissue examination and immunohistochemical evaluation of the CNS. D) In-vivo brain biopsy for PrPsc accumulation.

Answer 26

Postmortem microscopic tissue examination and immunohistochemical evaluation of the CNS.

Question 27

A group of pregnant ewes experiences late-term abortions. Examination of the aborted fetuses shows giant cell accumulation in mesenteric lymph nodes and lymphohistiocytic proliferations around blood vessels in the liver. Inspection of the placenta reveals characteristic thickened intercotyledonary membranes due to oedema and inflammation. These findings are most consistent with infection by?

Answer 27

Chlamydia abortus

Question 28

In the pathogenesis of Enzootic Abortion of Ewes, what is the first assumed site where Chlamydia abortus establishes itself after primary oronasal ingestion, leading to eventual dissemination?

Answer 28

The tonsil.

Question 29

A ewe has aborted due to Enzootic Abortion of Ewes. What is the typical subsequent reproductive history for this ewe, according to the provided information? A) She will likely abort again in the next pregnancy. B) She will become a persistent carrier and shed the organism continuously. C) She will generally abort only once and be immune to future infections. D) She will become sterile and unable to conceive again.

Answer 29

She will generally abort only once and be immune to future infections.

Question 30

The specific mechanism leading to abortion in Enzootic Abortion of Ewes is considered to be primarily due to: A) Direct fetal infection causing severe organ damage. B) Destruction of the chorionic epithelium. C) Systemic toxemia from widespread bacterial multiplication. D) Maternal fever causing hyperthermic stress on the fetus.

Answer 30

Destruction of the chorionic epithelium.

Question 31

A high-producing dairy cow, 12 hours post-parturition, presents with an inability to stand, weak peripheral pulses, gastrointestinal stasis (bloat), and a distended bladder on rectal examination. She has tucked her head into her flank. This clinical presentation corresponds to which stage of parturient paresis?

Answer 31

Stage 2

Question 32

Which of the following is an indirect consequence or complication of hypocalcemia (Milk Fever)? A) Direct muscle flaccidity leading to recumbency. B) Dystocia. C) Hyperexcitability progressing to paralysis. D) Undetectable peripheral pulses in severe cases.

Answer 32

Dystocia.

Question 33

A cow in Stage 3 parturient paresis is characterized by: A) Standing and ambulatory with fine tremors and ear twitching. B) An S-shaped curve to the neck while sternal. C) Progressive loss of consciousness to the point of coma and inability to maintain sternal recumbency. D) Restoration of normal gastrointestinal motility after calcium treatment.

Answer 33

Progressive loss of consciousness to the point of coma and inability to maintain sternal recumbency.

Question 34

A tick-infested sheep flock suddenly experiences a febrile illness with temperatures reaching 42 C. Clinical signs include depression, anorexia, mucopurulent to hemorrhagic nasal discharge, and severe, fetid dysentery causing painful straining. Several pregnant ewes have aborted. Given these signs, which disease is most likely?

Answer 34

Nairobi Sheep Disease

Question 35

Post-mortem examination of a sheep reveals soiling of the hindquarters with a mixture of blood and feces, severe dehydration, enlarged and edematous lymph nodes, and petechial and ecchymotic hemorrhages in the mucosa of the cecum and colon appearing as longitudinal striations. These findings are most consistent with?

Answer 35

Nairobi Sheep Disease

Question 36

Comparing the susceptibility of sheep and goats to Nairobi Sheep Disease, which statement is true? A) Goats are generally more susceptible and exhibit more severe clinical signs than sheep. B) Sheep are more susceptible than goats, but goats can still experience high mortality rates. C) Both species are equally susceptible, and clinical signs are identical. D) Colostral immunity offers no protection to lambs or kids from early life exposure.

Answer 36

Sheep are more susceptible than goats, but goats can still experience high mortality rates.

Question 37

The pathogenesis of Scrapie involves three distinct phases. Which of the following accurately represents the order of these phases? A) Neuroinvasion → Lymphoid dissemination → Entry into GALT B) Lymphoid dissemination → Entry into GALT → Neuroinvasion C) Entry into GALT → Lymphoid dissemination → Neuroinvasion D) Neuroinvasion → Entry into GALT → Lymphoid dissemination

Answer 37

Entry into GALT → Lymphoid dissemination → Neuroinvasion

Question 38

What microscopic lesion is characteristic of classical scrapie in the central nervous system?

Answer 38

Neuronal vacuolation and noninflammatory spongiform changes.

Question 39

In latently infected ewes with Chlamydia abortus, prior to the onset of abortion, how is the organism typically detected? A) High circulating maternal antibody titres are present. B) The organism is readily detectable by serology and PCR. C) The organism is undetectable by any means, including serology. D) Only fetal tissue samples will show the presence of the organism.

Answer 39

The organism is undetectable by any means, including serology.

Question 40

After the initial establishment of Chlamydia abortus infection in chorionic epithelial cells within the hilus of placentomes, how does the infection primarily spread to cause the characteristic placental lesions?

Answer 40

Centrifugal spread into the surrounding intercotyledonary membranes.

Question 41

A dairy cow presenting with fine tremors over the flanks and triceps, ear twitching, and head bobbing, but still able to stand and ambulate, is indicative of which stage of parturient paresis?

Answer 41

Stage 1

Question 42

Which of the following is NOT listed as a potential complication of hypocalcemia (Milk Fever)? A) Retained fetal membranes. B) Mastitis. C) Abomasal displacement. D) Development of wart-like cutaneous lesions.

Answer 42

Development of wart-like cutaneous lesions.

Question 43

The clinical course of Nairobi Sheep Disease is characterized by a febrile phase that typically persists for how long? A) Less than 24 hours. B) 1-7 days. C) 2-3 weeks. D) Several months.

Answer 43

1-7 days.

Question 44

A key post-mortem finding in Nairobi Sheep Disease, often appearing as longitudinal striations, is found in the mucosa of which organs?

Answer 44

Cecum and colon.

Question 45

What role does colostral immunity play in Nairobi Sheep Disease? A) It prevents lambs and kids from developing any form of active immunity. B) It offers no protection against the disease. C) It protects lambs and kids from early life exposure and allows for the development of active immunity. D) It exacerbates the severity of clinical signs in young animals.

Answer 45

It protects lambs and kids from early life exposure and allows for the development of active immunity.

Question 46

A dairy cow, 1.5 weeks postpartum, exhibits reduced feed intake, lethargy, and an empty-appearing abdomen. Her blood work is consistent with high serum ketone body concentrations. This presentation is most characteristic of which type of ketosis?

Answer 46

Type II ketosis primarily linked to fatty liver.

Question 47

In cows maintained in confinement stalls, what is typically the first observed clinical sign of ketosis?

Answer 47

Refusal of grain before forage.

Question 48

Which of the following clinical signs, if observed, would specifically indicate "nervous ketosis"? A) Reduced feed intake and an empty-appearing abdomen. B) Afebrile state and variable rumen motility. C) Incessant chewing on objects (pica) and aggression. D) Peripheral pulses becoming undetectable.

Answer 48

Incessant chewing on objects (pica) and aggression.

Question 49

Subclinical ketosis is primarily defined by: A) The presence of overt neurological signs without elevated ketone bodies. B) High serum ketone body concentrations with observed clinical signs. C) High serum ketone body concentrations without observed clinical signs. D) Reduced milk production as the only diagnostic criterion.

Answer 49

High serum ketone body concentrations without observed clinical signs.

Question 50

Mycoplasma capricolum subsp. capripneumoniae is an extracellular pathogen. What mechanism do mycoplasma commonly utilize to damage host cells?

Answer 50

Production of free radicals like hydrogen superoxide and superoxide radicals.

Question 51

Which of the following pathological changes is a direct result of Mycoplasma capricolum subsp. capripneumoniae colonization and is a key feature of CCPP? A) Neutrophilic meningitis. B) Serofibrinous pleuropneumonia. C) Granulomatous enteritis. D) Hepatic lipidosis.

Answer 51

Serofibrinous pleuropneumonia.

Question 52

In Infectious Bovine Rhinotracheitis (IBR), what is the long-term consequence of the BoHV-1 virus infecting local nerve cells and being transported to ganglia?

Answer 52

Establishment of a lifelong latent infection, making infected animals carriers.

Question 53

A cattle herd is experiencing an outbreak. Several animals show a high fever, coughing, excessive salivation, and a nasal discharge that progresses from serous to mucopurulent. Examination reveals inflamed nares, giving them a "red nose" appearance, and some have grayish necrotic foci on the septal mucosa. These clinical signs are most consistent with:

Answer 53

Respiratory form of Infectious Bovine Rhinotracheitis

Question 54

Which of the following is considered pathognomonic for IBRV respiratory tract infections? A) Petechial to ecchymotic hemorrhages in mucous membranes of the nasal cavity. B) Lymphocytic meningoencephalitis throughout the gray matter. C) Fibrinonecrotic rhinotracheitis. D) White foci in the liver, kidney, spleen, and lymph nodes.

Answer 54

Fibrinonecrotic rhinotracheitis.

Question 55

Abortions due to IBR can occur in infected dams. What is a key characteristic of these abortions regarding the severity of the dam's illness? A) Abortions only occur in dams with severe respiratory clinical signs. B) Abortions are always accompanied by visible genital lesions in the dam. C) Abortions can occur regardless of the severity of disease in the dam. D) Abortions primarily occur in the first trimester of pregnancy.

Answer 55

Abortions can occur regardless of the severity of disease in the dam.

Question 56

The rinderpest virus, after initial oronasal infection, primarily replicates within which cell type in lymphoid tissues?

Answer 56

Mononuclear leukocytes.

Question 57

What is the characteristic appearance of oral lesions in acute rinderpest cattle, appearing 2-5 days after the onset of fever? A) Ulceration of the buccal mucosa with no purulent discharge. B) Tiny, pinpoint greyish areas of necrosis on the gum and lips that enlarge and coalesce to form a thick, yellow pseudo-membrane. C) Vesicles and bullae that rupture quickly, leaving raw erosions. D) Proliferative, cauliflower-like growths on the tongue and soft palate.

Answer 57

Tiny, pinpoint greyish areas of necrosis on the gum and lips that enlarge and coalesce to form a thick, yellow pseudo-membrane.

Question 58

A distinguishing feature of acute rinderpest in cattle is the presence of a "foul odour" emanating from which body part?

Answer 58

The mouth, due to necrotic oral lesions.

Question 59

In severe post-mortem cases of Rinderpest, which characteristic lesion is commonly described as "zebra striping"? A) Hemorrhages in the heart muscle. B) Linear hemorrhages in the large intestines, especially around the ileo-caecal valve and caecal tonsils. C) Petechial hemorrhages on the serosal surfaces of the lungs. D) Necrotic foci in the liver and spleen.In severe post-mortem cases of Rinderpest, which characteristic lesion is commonly described as "zebra striping"?

Answer 59

Linear hemorrhages in the large intestines, especially around the ileo-caecal valve and caecal tonsils.

Question 60

A cow in early lactation (5 weeks postpartum) presents with reduced milk production, lethargy, and an empty-appearing abdomen. The herd manager notes the cow is refusing grain but still consuming some forage. This scenario, occurring around peak milk production, is most consistent with?

Answer 60

Type I ketosis, associated with a metabolic shortage of gluconeogenic precursors

Question 61

While examining a cow suspected of ketosis, the veterinarian notes that the cow is afebrile and slightly dehydrated. Rumen motility is hyperactive. Based on the provided information, what can be concluded about rumen motility in ketosis cases? A) Rumen motility is consistently hypoactive in all ketosis cases. B) Rumen motility is consistently hyperactive in all ketosis cases. C) Rumen motility is always normal in ketosis. D) Rumen motility can be variable, ranging from hyperactive to hypoactive.

Answer 61

Rumen motility can be variable, ranging from hyperactive to hypoactive.

Question 62

Beyond the respiratory tract, Mycoplasma capricolum subsp. capripneumoniae may also affect which other organ systems?

Answer 62

Joints, eyes, and udder.

Question 63

If secondary bacterial infections, such as Pasteurella/Mannheimia bronchopneumonia, complicate IBR, what additional lesion might be found in the nasal cavity and paranasal sinuses? A) Fibrinonecrotic rhinotracheitis without further changes. B) Lymphocytic meningoencephalitis. C) Petechial to ecchymotic hemorrhages. D) White foci in the liver and spleen.

Answer 63

Petechial to ecchymotic hemorrhages.

Question 64

In an aborted fetus due to IBR, what is a characteristic lesion, particularly prevalent in the liver?

Answer 64

Pale, focal, necrotic lesions in all tissues.

Question 65

A cow suffering from acute rinderpest begins to show diarrhea. What is a typical characteristic of these feces in later stages of the illness?

Answer 65

Initially thin and dark, later watery and containing mucus, epithelial shreds, and specks of clotted blood.

Question 66

The persistence of Caprine Arthritis and Encephalitis Virus (CAEV) in the host is primarily facilitated by its ability to: A) Induce a strong and protective humoral immune response. B) Become sequestered as provirus within host cells. C) Cause rapid destruction of infected lymphocytes. D) Replicate exclusively in the gastrointestinal mucosa.

Answer 66

Become sequestered as provirus within host cells.

Question 67

A 4-month-old kid goat presents with progressive weakness, ataxia, hind limb proprioceptive deficits, and hypertonia. This clinical presentation is most indicative of which manifestation of CAE?

Answer 67

Encephalomyelitis.

Question 68

Despite inducing strong humoral and cell-mediated immune responses, how effective are these responses in protecting the host against CAEV infection? A) Both responses are fully protective, leading to viral clearance. B) Humoral immunity provides partial protection, but cell-mediated immunity does not. C) Neither response is protective against the infection. D) Only cell-mediated immunity is protective, but it is often delayed.

Answer 68

Neither response is protective against the infection.

Question 69

What is the most common route of entry for Corynebacterium pseudotuberculosis to establish infection, particularly in sheep and goats?

Answer 69

Penetration of skin after injury (e.g., shearing, tail docking).

Question 70

Corynebacterium pseudotuberculosis produces an exotoxin called phospholipase D. What is the primary function of this virulence factor in the pathogenesis of CL? A) To induce immediate systemic inflammatory shock. B) To enhance bacterial dissemination by damaging endothelial cells and increasing vascular permeability. C) To directly lyse host phagocytes. D) To form the characteristic encapsulated abscesses.

Answer 70

To enhance bacterial dissemination by damaging endothelial cells and increasing vascular permeability.

Question 71

A sheep flock is experiencing chronic weight loss, failure to thrive, and some animals present with a cough, purulent nasal discharge, and increased lung sounds. Abscesses are not readily visible externally. This clinical presentation suggests which form of Caseous Lymphadenitis?

Answer 71

Internal CL, also known as "thin ewe syndrome."

Question 72

The purulent material from external CL abscesses in goats is typically described as: A) Thick and caseous, with a foul odor. B) Soft and pasty, with no odor. C) Watery and hemorrhagic. D) Green and granular, with a strong odor.

Answer 72

Soft and pasty, with no odor.

Question 73

A young lamb, 12 days after tail docking, presents with localized stiffness in the hind limbs, difficulty chewing (lockjaw), and an extended head and neck ("sawhorse" stance). It exhibits an exaggerated startle response to minor stimuli. These signs are highly characteristic of:

Answer 73

Tetanus.

Question 74

Besides the neurotoxin, Clostridium tetani produces another toxin called tetanolysin. What is the known function or pathology associated with tetanolysin?

Answer 74

It is a hemolysin with no known function or pathology related to clinical tetanus.

Question 75

In late gestation, the substantial glucose requirement of fetuses in pregnant ewes and does primarily leads to: A) A significant increase in maternal insulin production. B) Preferential direction of the ewe's glucose production towards the fetuses. C) A decrease in fat mobilization from maternal stores. D) Enhanced hepatic detoxification processes.

Answer 75

Preferential direction of the ewe's glucose production towards the fetuses.

Question 76

A multiparous ewe, 2 weeks before parturition, is observed spending more time recumbent and shows a selective anorexia, particularly refusing grain. As the disease advances, she develops listlessness, muscle tremors, and eventually becomes blind and ataxic. These clinical signs are most consistent with:

Answer 76

Pregnancy Toxemia.

Question 77

Postmortem examination of a ewe that died from suspected pregnancy toxemia reveals fatty liver and enlarged adrenal glands. Analysis of postmortem aqueous humor for beta-hydroxybutyrate (BHB) would likely show concentrations:

Answer 77

> 2.5 mmol/L

Question 78

What is a key factor that increases the susceptibility of thin ewes or does to pregnancy toxemia? A) An underlying viral infection. B) A chronically inadequate ration or other diseases limiting feed intake. C) Excessive consumption of high-protein supplements. D) A rapid increase in body condition score late in gestation.

Answer 78

A chronically inadequate ration or other diseases limiting feed intake.

Question 79

The pathogenesis of Heartwater involves the replication of Ehrlichia ruminantium organisms within which specific host cells, particularly those of the brain?

Answer 79

Endothelial cells of blood vessels.

Question 80

A striking post-mortem finding in most fatal cases of Heartwater, especially more pronounced in sheep and goats than cattle, is: A) Severe consolidation of the lungs with no fluid accumulation. B) Effusion of body cavities, including hydropericardium and hydrothorax. C) Grossly enlarged and hemorrhagic lymph nodes throughout the body. D) Petechial hemorrhages primarily on the skin surface.

Answer 80

Effusion of body cavities, including hydropericardium and hydrothorax.

Question 81

An animal in the acute form of Heartwater exhibits anorexia, depression, and congested mucous membranes. As the disease progresses, it develops a high-stepping stiff gait, exaggerated blinking, and chewing movements. These nervous signs are primarily attributed to: A) Direct damage to muscle fibers. B) Severe dehydration and electrolyte imbalance. C) Oedema of the brain. D) Peripheral nerve demyelination.

Answer 81

Oedema of the brain.

Question 82

In the context of Ehrlichia ruminantium within endothelial cells, what are the "elementary bodies" commonly referred to as?

Answer 82

The infective stage of the organism.