Open AccessPrevalence of coagulase-negative staphylococci in bovine mastitis in Zimbabwe
Author(s) -
Timothy Kudinha,
Clifford Simango
Publication year - 2002
Publication title -
journal of the south african veterinary association
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.535
H-Index - 31
eISSN - 2224-9435
pISSN - 1019-9128
DOI - 10.4102/jsava.v73i2.557
Subject(s) - coagulase , microbiology and biotechnology , mastitis , cloxacillin , penicillin , staphylococcus , biology , staphylococcus epidermidis , somatic cell count , udder , staphylococcal infections , staphylococcus aureus , antibiotics , bacteria , pregnancy , lactation , ice calving , genetics
This study was carried out to determine the prevalence of coagulase-negative staphylococci in clinical and subclinical mastitis in commercial and small-scale farms in Zimbabwe. Thirty five quarter milk samples from clinical mastitis cases and 371 quarter milk samples from cows with subclinical mastitis were cultured for bacterial pathogens. The most frequent pathogens isolated in clinical mastitis were the enteric bacteria (31.4%), followed by coagulase negative staphylococci (22.9%) and then Staphylococcus aureus (17.1%), whereas in subclinical mastitis S. aureus (34.2%) and coagulase-negative staphylococci were (33.2%) the most common. Bacillus species were only isolated in milk samples from subclinical mastitis. Coagulase-negative staphylococci were observed in mixed infections with other bacteria in only 2.2 of the 406 milk samples from clinical and subclinical mastitis where they were isolated together with Bacillus species in 6 of the 9 mixed infection cases. About 95% of the milk samples from which 131 coagulase-negative staphylococci were isolated had correspondingly high somatic cell counts. The coagulase-negative staphylococci isolated most frequently were S. chromogenes (7.9%), S. epidermidis (7.4%) and S. hominis (5.9%). They were all associated with high somatic cell counts. All the coagulase-negative staphylococci isolates were susceptible to cloxacillin and erythromycin, and more than 90% of the isolates were susceptible to neomycin, penicillin and streptomycin. The highest resistance was to tetracycline (17.6%), followed by lincomycin (13.7%). About 8% of the isolates were resistant to both penicillin and streptomycin.