Studies on subclinical mastitis in dairy cows and their response to invitro sensitivity

Abstract EN

This study was carried out on milk samples from one hundred dairy cow of different dairy farms in El-Behera Governorates.

Milk was examined for detection of subclinical mastitis using California Mastitis Test (CMT).

Incidence of subclinical mastitis by using this test was 29% and negative samples were 71%.

All positive CMT samples were examined microbiologically for isolating the most causitive microbial agent of subclinical mastitis.

Milk samples were examined to determine the prevalence of major contagious pathogens of mastitis.The contagious pathogens isolates were tested for in vitro-sensitivity.

Infectious organisms isolated from CMT positive samples were Streptococcus agalactiae (65.5%), Staphylococcus aureus (13.7%), E.coli (37.9%), Pseudomonas aeruginosa (2o.6%) and S.dysagalactiae (6.8%).

Also the sensitivity test of the isolated organisms to eleven antibacterial agents were discussed .

It was found that most isolated organisms were susceptible to Chloramphenicol, Gentamycin, Norfloxacin and Nitrofurantoin and resistant to Penicillin G and ampicillin .It was concluded that the subclinical mastitis in dairy cows is a serious problem in the study area.