Study of bovine mastitis in asella government dairy farm of Oromia Regional state, South Eastern Ethiopia

A study was conducted between December, 2012 and January, 2013 to estimate prevalence, isolate major bacterial pathogens for mastitis and to establish antimicrobial sensitivity for isolates in Asella government dairy farm. A total of 66 lactating cows and 264 quarters were constituted in the study based on clinical and California Mastitis Test (CMT). Accordingly, 44(66.6 %) cows had mastitis, which 8 (12.1%) clinical and 36(54.5 %) sub clinical and 111(42.04%) quarters were positive either clinically or under screening tests. Out of collected and cultured samples, 70(63%) samples were positive for aerobic and one facultative an aerobic bacteria. The following bacteria were isolated: Staphylococcus aureus (35.71%), Coagulase negative sthaphylococcus (15.71%), Streptococcus spp (11.42%), staphylococcus intermidius (7.14%), E. coli (5.71%), P. haemolytica (7.14%), P.aureuginosa (4.28%), Bacillus species (5.71%) and micrococcus species (7.14%). Out of eight in-vitro antimicrobials test, Gentamaycine, Chloroamphenicol and Kanamaycine were susceptible to all isolates and Vancomycine susceptible to gram positive isolates but many were resistance to penicillin and tetracyclines, which are most commonly, used drugs in the farm. Improving farm management system, regular screening test for sub clinical mastitis and use of antibiotics by sensitivity testing and culling chronically infected cows were recommended to reduce economic loss from K E Y W O R D S Mastitis; Antibiotic