2. Aerobic, Gram-negative bacilli Appear as cocci, coccobacilli and short bacilliNon-motile, non-capsulate Optimum temp. >> 37oC Facultative intracellular parasites Essentially pathogens of goats, Cattle, sheep and pigs Causativeagents of Brucellosis (typical zoonosis) worldwideAlso known as Malta, Mediterranean or undulant fever 3. Importantspecies B. melitensis >> goats & sheep B. abortus >> cattle B. suis >> pigs Important:All 3 species can infect man and domestic animals 4. Brucella speciesgram-negative bacilli 5. Brucella abortus 6. PATHOGENESIS Incubation period: 10-30 days Symptoms may be delayed for months Enter the body through: Skin abrasions, mucous membranes of the alimentary or respiratory tracts and sometimes the conjunctivae>> reach the blood through regional lymphatics. Symptoms may vary without the fluctuating temperature to act as guide. Bacteria localize in various parts of the reticulo-endothelial system resulting in complications in any part of the body. Symptoms include: malaise, low-grade fever, lassitude, insomnia, irritability and swelling around the joints. 7. LABORATORY DIAGNOSIS 1. Blood Culture Specimen Blood (10 ml volumes) Inoculate Blood culture tubes or bottles (glucose-serum broth) Incubate in 10% CO2 Cultures should be retained for at least 6-8 weeks before being discarded as negative 8. Brucella melitensis colonies 9. 2. Serological Tests Standardagglutination test Mercaptoethanol test Complement fixation test Coobs test3. Brucellin Skin Test 10. TREATMENT AND CONTROL Combination of streptomycin and tetracycline or rifampicin and doxycyclineVaccination of young cattle (6-8 months) Pasteurization of milk or milk products Eradication by compulsory testing animals and slaughtering positive reactors.
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