Incidence of Aerococcus viridans in Raw Cow Milk in Sohag City, Egypt

Aerococcus viridans considered the second bacterial cause of mastitis in bovine with unclear pathogenic changes role. Therefore, the current study was conducted to investigate incidence of subclinical mastitis and A. viridans in 100 raw milk samples collected from different dairy cattle breeding farms in Sohag city, Egypt, its effect on some milk composition and their antibiotic resistance was described. Subclinical mastitis was detected in high incidence rate (92%). A total of eleven A. viridans isolates were identified from 92 bovine subclinical mastitis cases. Comparatively with milk of healthy cows, the mean chloride content (%) of infected milk was 0.110 ± 00013, which showed highly significant (P = 0.01) increase, while, the mean lactose (%) decreased significantly. All A. viridans isolates were 100% susceptible to Streptomycin, Amikacin and Ciprofloxacin, and followed by (90.91%) to Vancomycin while, all A. viridans isolates were highly resistant to Penicillin G, Ampicillin and Cefotaxime. This study concluded that A. viridans play an important role in subclinical mastitis infection in bovine in Sohag city, where it exerts an effect on some milk composition and contaminated milk considered as a hazard for human health.