Chapter 13 Flashcards
(60 cards)
Anthrax
Bacillus anthracis Source: Contaminated soil- spread by insects Signs: acute, febrile, septicemia, death- ataxia and bleeding from orifices *Bleeding from the orifices and the absence of rigor mortis are clinical signs of anthrax* Diagnosis: blood smear Treatment: None, oxytet or penicillin if early Prevention: Vaccination- ****Zoonotic: REPORTABLE DISEASE***
Brucellosis
Brucella abortus Source: infected placentals, fetuses, milk, uterine discahrge, congenital infection can occur
Signs: *Brucellosis causes abortion in cattle between 7 and 8 months of gestation. Or epididymitis in bulls*
Diagnosis: blood agglutination, milk ring tests, CF tests, Rose Bengal Test Treatment: None, Prevention: Vaccination calves 4-8 months old and screening
*Zoonotic: Brucellosis causes undulant fever in humans.*
Blackleg
Etiological Agent: Clostridium chauvoei Source: Signs: Cattle diagnosed with blackleg are often found dead. Diagnosis: Histopathology, necrotic muscle on necropsy, fluroescent antibody Treatment: None, if you catch it early penicillin and NSAIDs Prevention: Vaccination
Calf Enteritis
incl prevention
Etiological Agent: E.Coli, clostridium perfringens, rotavirus and corona virus, cryptosporidiosis, salmonella
Source: *Calf scours is a major cause of death in the first few weeks of life*
Signs: Diarrhea, *dehydration* Treatment: supportive care, dehydration care
*Prevention: proper passive transfer, vaccination and good feeding practices* *Zoonotic: Yes*
Foot Rot
Dichelobacter nodosus, fusobacterium necrophorum
Signs: lameness, inflammation and necrotic tissue
Diagnosis: clinical signs
Treatment: debridement and hoof trimming- topical antibacterial agents and /or astringents
*Prevention: proper management, foot baths*
Johne Dz
Mycobacterium avium paratuberculosis
Signs: silent, subclinical, clinical and advanced clinical- weight loss and profuse watery diarrhea, decreases in production
Diagnosis: clinical signs, IFA test
Treatment: depopulation ***Johne disease is difficult to remove from herds. Prevention: proper management , culling all heifers from infected cows, good hygiene, and pasteurization of pooled colostrum
Zoonotic: Yes possible relation to crohn disease****
Lepto
Etiological Agent: Spirochete leptospira (bacterium) Source: contaminated environment with urine Signs: abortion storm, loss of milk, septicemia, hemoglobinuria, *Leptospirosis often presents as an abortion storm.* Diagnosis: swollen dark kidneys on necropsy, paired serum samples Treatment: vaccination and antibiotic therapy Prevention: vaccination *Zoonotic: Yes*
Listeriosis
Bacterium Listeria monocytogenes Source: *Listeriosis is often contracted through contaminated silage.* Signs: fever, facial nerve paralysis, tongue hanging from mouth, circling, drooping ears, blindness, abortion Diagnosis: Culture Treatment: penicillin and nsaid Prevention: proper management of silage feeds
Lumpy Jaw
Bacterium Actinomyces bovis Source: skin punctures, oral punctures Signs: mass formation on the mandible Diagnosis: clinical signs Treatment: often ineffective - Debridement and antibiotics
Malignant edema
Etiological Agent: Clostridium septicum Source: soil and GI tracts of some animals Signs: Formation of edematous areas, loses weight and then toxemia Treatment: Penicillin and NSAID Prevention: Vaccination
mastitis
Etiological Agent: *95% are caused by Streptococcus agalactiae, and Staphylococcus aureus*, others coliforms- release endotoxins Source: Cow to cow Signs: Clinical mastitis- clinical signs- clumps or foul odor- hot mammary gland or visualization of abnormal milk as above Subclinical mastitis-sampling and testing, no visible signs Diagnosis: sampling testing milk *strip cup tests cheapest screening* Treatment: antibiotics and good sanitation for Strept ag. Staphylococcus aureus causes microabcesses
Types of mastitis
Contagious mastitis: Can be spread directly from cow to cow, usually at milking time (milking machines or contaminated hands or towels). Environmental mastitis: Spread to individual cows through environmental contamination of bedding, soil, standing water, or feces. Gangrenous mastitis: Severe infection that results in destruction of the affected quarter, with necrosis and sloughing. Severe Staphylococcus infections and wounds that allow Clostridium spp. to become established may result in gangrenous mastitis. Clinical mastitis: Visible signs of disease in the milk and/or the affected quarter. Subclinical mastitis: No visible signs of disease. Causes the greatest economic loss to dairy farmers because of lowered production. Requires special diagnostic testing of the milk for diagnosis.
mastitis tests
Strip cup examinations are the cheapest screening test available for mastitis. First milk (foremilk) is squirted onto the black lid and observed for abnormalities and odor CMT Uses white paddle and CMTM which gels when there is increased somatic cells *To interpret results of the California mastitis test, technicians observe the consistency and color changes that occur within the sample.*
somatic cell counts
indirectly measure leukocytes and epith cells entering mammary gland as a result of damage
CMT Scores
Test Score Interpretation in Cattle N Normal (0–200,000 cells/ml) T Normal (150,000–500,000 cells/ml) 1 Suspicious (500,000–1,500,000 cells/ml) 2 Mastitis (1,500,000–5,000,000 cells/ml) 3 Mastitis (>5,000,000 cells/ml)
metritis
Etiological agent: Common causes Actinomyces, corynebacterium pyogenes, streptococci, staphylococci, coliforms, and gm - anaerobes Source:Uterine infections are commonly associated with dystocia and retained placentas. Signs: whitish to yellowish mucopurulent vaginal discharge Diagnosis: signs Treatment: antibiotics Prevention: hygiene
pinkeye
Etiological agent: Moraxella bovis Source: *Dry dusty environments can exacerbate pinkeye.* Signs: blepharospasm, lacrimation, photophobia, keratitis, conjunctivitis, corneal opacity and ulceration Diagnosis: Clinical signs Treatment: antibiotic therapy and isolation Prevention: Low stocking rates, fly prevention
Shipping Fever
Etiological Agent: Mannheimia haemolytica and Pasteurella multocida Source: The bacteria that cause shipping fever are normal flora of the upper respiratory tract. Signs: depression, low head carriage, wet cough, open-mouth breathing, weight loss, fever, wheezing, crackling Treatment: antimicrobial therapy and NSAIDs Prevention: hygiene, environmental hygiene, vaccinations
Vibriosis
Etiological Agent: Gram-neg or spiral polar flagellated Campylobacter fetus Source: venereally, contaminated instruments, infected semen or bedding. Signs: Early embryonic death Diagnosis: Culture Prevention: Vaccinations, antibiotic treated semen
wooden tongue
Etiological Agent: Actinobacillus lignieresii Signs: *Wooden tongue causes abscesses on the tongue that result in swelling of the ventral jaw* Treatment: Tetracycline, erythromycin or tilmicosin
Bovine Spongiform Encephalopathy
Etiological Agent: Prion Source: Ingestion of infected meat and bone meal Signs: nose licking, teeth grinding, snorting and leads to ataxia, muscle tremors Diagnosis: Brain tissue prion identification Treatment: None Prevention: control of by-product feeding Zoonotic: No *Political and economic losses make prevention of bovine spongiform encephalopathy outbreaks extremely important.*
Dermatophytosis
Etiological Agent: Trichophyton verrucosum or Microsporum spp. Source: Spores in the environment Signs: *Ringworm often causes encrusted circular lesions on the head and neck* Treatment: spontaneous remission or antifungals Prevention: Sunshine Zoonotic: YES
Trichomoniasis
Etiological Agent: Tritrichomonas faetus, a protozoan Source Infected animals Signs: Early embryonic death Diagnosis: Culture Treatment- cull bulls and separate cows who are infected. Prevention: **Tritrichomonas foetus can survive the semen freezing process.**
Bovine Respiratory Syncytial Virus
Paramyxovirus RNA
nasal and ocular discharge
Virus Isolation, or paired sera
Treatment: Supportive care
Prevention: Vaccinations
