SOME EPIDEMIOLOGICAL ASPECTS OF MASTITIS IN COWS AND BIOCHARACTERIZATION OF ISOLATED STAPHYLOCOCCI

Abstract

Among one thousand cows, 220 animals were positive for mastitis thus the point prevalence being 22 per cent. Of the total milk samples, 486 (12.21%) were positive by White side test and 10.93 per cent by pH indicator paper technique. Incidence was higher in hind quarters as compared to the fore-quarters and slightly higher in right quarters than the left ones. Incidence of mastitis was the maximum(23.19%) in crossbred cows and the minimum (7.69%) in nondescript indigenous breeds. Occurrence of mastitis increased with the increase in age and number of lactations.The disease was more prevalent in cows during the first month of lactation (24.90%). Prevalence of mastitis was higher in farm than in field conditions. The occurrence of mastitis was lower in cows where washing of udders was carried out prior to milking. Suckling of calf showed a nonsignificant effect. A total of 190 milk samples were positive for bacterial isolations. Various isolated pathogenic microorganisms were Staphylococcus aureus (32.09%), coagulase negative staphylococci (12. 06 % ), E. coil (16.o8), Streptococcus agalactiae (3. 01 % ), Streptococcus uberis (7%), Pseudomonas aeruginosa (7.5%), Corynebacteriwn pyogettes (3.51%), Bacillus (3.01%) and Klebsiella (2.01 %). Total fungal isolates were 1 1 , among which 9 were Candida and 2 were Aspergillus. The staphylococci were highly sensitive to oxytetracycline , sulphamethaxazole/ trimethopritu and chloramphenicol, while streptococci were highly sensitive to oxytetracycline, erythromycin and chloramphenicol. E.coli was sensitive to oxytetracycline , gentamicin, chloramphenicol and streptomycin. All DNAse positive Staphylococcus aureus strains were coagulase positive. Penicillin resistance was showed by 49.24 per cent Staph. aureus cultures and 50 per cent coagulase negative staphylococcus strains. Out of 32 penicillin resistant strains of Staphylococcus aureus, 26 (81.25%) were resistant due to penicillinase production.