164. Leptospira diseases of cattle.

Question 1

Bovine leptospirosis occurence aetiology epidemiology?

Answer 1

Bovine leptospirosis

Occurrence:

• worldwide,
• common; intensive units, pasture

Aetiology:

• L. Pomona,
• L. Grippotyphosa,
• L. Hardjo

Epidemiology

• Seasonal fluctuation, pasture
• Swine: L. Pomona
• Rodents: L. Hebdomadis, L. Sejroe, L. Saxkoebing, L. Grippotyphosa
• Peptospira with own cycle: L. Hardjo

Question 2

Clinical signs and pathology?

Answer 2

Clinical signs

• Incubation time 3-14 days
• Course is influenced by: virulence of the agent, age, individual resistance
• young animals: more severe
• Old animals: frequently asymptomatic
• Calf:
• Fever, anorexia, increased heard rate, breath rate
• Haemoglobinuria, anaemia, jaundice,
• Central nervous clinical signs
• Pregnant cow: abortion, stillbirth, not viable foetus
• Milking cow: fever, anorexia, mastitis, agalactia

Pathology

• Calf:
• Haemorrhages, reddish exudate in body cavities
• Liver yellowish brown, parenchymal organs enlarged
• Jaundice, anaemia, focal interstitial nephritis, red urine
• Foetus: autolysis, anaemia, jaundice (exc. L. Hardjo), reddish fluid, enlarged liver

Question 3

Diagnosis treatment and prevention eradication?

Answer 3

Diagnosis

• Epidemiology – clinical signs – pathological lesions
• Detection of the agent: microscopy, PCR, histology, culture
• Detection of antibodies: microagglutination test, ELISA; excepting L. Hardjo
• Differential diagnosis: campylobacteriosis, brucellosis, salmonellosis, IBR

Treatment:

• penicillin, streptomycin, tetracyclines, etc. - before liver lesions

Prevention

• General epidemiological measures
• Isolated keeping, isolation of age groups
• Rodent control
• Clean water
• Vaccines
• Serotypes: monovalent - multivalent
• Inactivated
• Two vaccinations are needed
• Half a year long protection
• Eradication:
• antibiotics (penicillin 25 mg/kg 3 days), prevention of reinfection