A total of 1164 indivedual quarter milk samples collected from220 and 71 apparently healthy CO\Vs and buffaloes respectively wereexamined bacteriologically as well as by screening tests, for detection ofsubclinical mastitis.The incidence percentage of subclinical mastitis among lactatingcows and buffaloes were 45.45% and 32.39% respectively.Bacteriological examination of the milk samples revealed thatStrept. dysgalactiae and E. coli were the most prevalent microorganismsMeanwhile other rats treated with therapeutic dose of novalgin, levamisole and citarin alone showed increase in the body weights.Macroscopically, the liver was congested, friable pale, yellowishstreaks and showed haemorrhagic spots in all experimental rats. It was firmin consistency in some rats received double therapeutic dose of combinedparacetamol-levamisole. The kidneys were congested, enlarged, pale andfriable in all experimental rats. Grayish patches were seen in rats treated