SOME PATHOGENIC BACTERIA OF PUBLIC HEALTH IMPORTANCE IN COW'S MILK SOLD IN MARKETS

Abstract

The objective of this study was to determine the incidence of E. coli, Salmonellae, Staph. aureus and Streptococcus species in raw cow's milk and their resistance and sensitivity to nine antibiotics. One hundred raw cow's milk samples were collected from different markets in Kafrelsheikh Governorate which sold uncooled. Aerobic plate count showed a mean value of 4.28x105 ±1.23x105 cfu/ml. The results revealed that 72 samples were positive to pathogenic bacteria, 12 isolates of E.coli (2 isolates each of O26:H11, O91:H21, O124:H30 and O128:H2 and 4 isolates of O111:H2), 6 isolates of Salmonellae (4 isolates of S. typhyimurium and 2 isolates of S. infantis), 34 isolates of Staph. aureus and 20 isolates of Streptococcus spp. (St. agalactiae and dysgalactiae (6 isolates for each ), St. uberis (4 isolates), St. pyogenes and St. viridans (2 isolates for each). The isolated strains were subjected to antibiotic sensitivity test which resulted in the highest sensitivity of E.coli toCiprofloxacin (66.66%), for Salmonellae, Ciprofloxacin and Gentamicin (66.66%), for Staph. aureus, Amoxycillin+Clavulonic acid (85.29%), and for Streptococcus spp., Amoxycillin+Clavulonic acid (90%). On the other hand the highest resistance of E. coli was to Penicillin P and Clindamycin (100%), for Salmonellae, Penicillin P and Clindamycin (100%), for Staph. aureus, Sulphamethoxazole+Trimethoprim (64.70%) and Streptococcus spp. were to Streptomycin (60%). Public health importance of the isolated organisms was discussed. Improving hygienic conditions and careful handling of cow during milking should be followed to limit the spread of such bacteria to humanswere recommended and limited the use of antibiotics to decrease bacterial resistance.