Prevalence, control and antimicrobial susceptibilty patterns of bovine mastitis causing bacteria in Mityana District

Abstract

Mastitis is one of the most prevalent and costly diseases affecting the dairy industry worldwide and it is one of the most underestimated diseases of dairy cattle by many dairy cattle owners. A study was done in Mityana District to determine the prevalence and causes of mastitis, the antibiotic susceptibility patterns of the associated microorganisms as well as to determine the knowledge and practices farmers employed in controlling mastitis. One hundred and fifty one lactating cows were screened for mastitis using California Mastitis Test (CMT) in the field. Milk samples that were CMT positive were cultured in the laboratory to establish the causative microorganisms and thereafter the microorganisms were tested in vitro for antimicrobial susceptibility. A questionnaire was administered to 87 farmers to collect data regarding mastitis control and dairy farm management. The prevalence of mastitis determined by CMT was 49% (74/151) and out of the 74 cows, fifty eight (58) cows were culture positive therefore prevalence by culture was 78% (58/74). The causative microorganisms were Coagulase Negative Staphylococci (41%), Streptococcus spp (19%), Corynebacteria spp (16%), Staphylococcus aureus (10%), Streptococcus agalactiae (7%), Bacillus spp (4%), Streptococcus fecalis (1%), Lactobacillus spp (1%) and E.coli (1%). The isolated microorganisms were highly sensitive to Gentamycin (98.2%), Neomycin (83.9%), Sulfamethoxazole +Trimethoprim (74.7%), moderately sensitive to Tetracycline (61.9%) but less sensitive to penicillin (53.5%) and Cloxacillin (33.0%), the commonly used drugs in treating clinical mastitis in the study area. This study indicated that many farmers (73.5%) washed the teats of the cows before milking as main method applied in controlling mastitis but few farmers (1.9 %) applied dry cow therapy in controlling mastitis. Maintaining good hygiene and high treatment costs were the major challenges farmers faced in controlling mastitis. High treatment costs coupled with low income from milk sold by farmers limited the control measures farmers could apply to reduce mastitis on their farms. The observed prevalence of mastitis in this study could be partly due to inadequate methods farmers applied in controlling mastitis on their farms and zero grazing units. The recommended antibiotics for controlling mastitis in Mityana are Gentamycin, Neomycin and Sulfamethoxazole+ Trimethoprim.