Abstract:

OBJECTIVE: This study was aimed to detect the aerobic bacteria from the cow milks with subclinical mastitis. METHODS: A total of 125 lactating dairy cows in four dairy farms were examined in terms of mastitis by clinical observations, California mastitis test (CMT), somatic cell counts (SCC) and bacteriological analysis of milk samples. CMT positive-results scored as (+1), (+2) and (+3). SCC were determined by the DeLaval cell counter® (DCC). RESULTS: There was no evidence of clinical mastitis in dairy cows examined. The CMT results of 499 quarter milk samples from 125 cows; 42 cows negative (33,6%), 83 cows positive (66,4%), 156 milk samples positive (31,3%) and 343 milk samples negative (68,7%). SCC for the milk samples which were scored as CMT (+1), (+2) and (+3), was found to be in the range of 114.120–382.100, 436.000–1.413.200 and 1.879.640–3.882.100 cell/mL, respectively. SCC for CMT negative milk samples was determined in the range of 23.500–241.200 cell/mL. As the results of the bacteriological analysis of 156 milk samples from 83 cows; while microbiological culture were positive in 117 milk samples (75%) from 58 cows (69,9%), 39 milk samples (25%) from 25 cows (30,1%) were negative. A total of 120 bacterial strains isolated from the milk samples were 48 (%41,0) Staphylococcus aureus, 20 (%17,1) coagulase negative staphylococci (CNS), 14 (%12,0) Enterobacter aerogenes, 11 (%9,4) Escherichia coli, 10 (%8,5) Streptococcus spp., 8 (%6,8) Klebsiella pneumoniae, 6 (%5,1) Citrobacter spp. and 3 (%2,6) Bacillus spp. CONCLUSION: S. aureus is the most fruquently isolated bacterium from the cow milks with subclinical mastitis.

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