الفهرس | Only 14 pages are availabe for public view |
Abstract A total of 244 quarter milk sample from apparently healthy lactating cows were collected for detection of subclinical mastitic animals. Diagnosis of subclinical mastitis was performed by applying different diagnostic techniques as CMT, SCC, NAGase test. Bacteriologal examination was performed for isolation of coliform bacteria. Coliform bacteria were isolated and identified in 23.7 % of samples. from these samples 5.3 %, 7 % and11.4% were positive for E. coli, Klebsiella sp. and other coliforms respectetivly. Thirteen E. coli isolates were serologically identified and the results revealed 3 strains 0: 111, 3 strains 0: 128 and 7 untypable strains. To find out the correlation between virulence factors of E. coli strains and induction of subclinical mastitis multiplex peR was performed on E. coli isolates. Virulence genes which detected by PCk. were Stx 1, Stx2, Sta, intimine and F41. Results show that 5 strains have Stx1, 6 strains have Stx2, 5 strains have Sta gene, 7 strains have intimine gene, one strain have F41 gene and one strain have no virulence gene of those genes. Hematological and biochemical examination were done on 66 whole blood and serum samples collected from examined cows. Results revealed that no hematological or biochemical changes observed which indicate that there is no correlation between subclinical coliform mastitis and hematological or biochemical changes. Our investigation revealed that no correlation could be observed between studied virulence genes and the induction of subclinical mastitis. |