Identification, Serological and Molecular Identification of Coliform Bacteria Recovered from Bovine Mastitis

Abstract

Aim/Background: Mastitis is one of the serious disease and critical problem in the dairy industry worldwide. This study aimed to determine the prevalence of coliform bacteria, particularly E. coli, associated with mastitis in dairy herds. In addition, serological identification and molecular detection for E. coli strains from bovine mastitis. Methods: A total of 400 cows were inspected for clinical and subclinical mastitis, and 100 samples (64 and 36, respectively) from these conditions were collected for bacteriological identification before being subjected to serological and molecular analysis. Results: Clinical and subclinical mastitis were prevalent; 16% and 9%, respectively. Bacteriological examination revealed that E. coli was the most prevalent bacteria 16 isolates (19.51%) followed by Klebsiella spp 8 (9.76%), Citrobacter 4 (8.16%), and Enterobacter aerogens 2 (4.08%). Regarding to the serological results, E. coli isolates classified into EHEC which was the most identified serotype followed by EPEC and ETEC serotypes. While, for Klebsiella spp., Klebsiell aoxytoca and Klebsiella pneumonia were serologically identified. The molecular detection some of the virulence genes by PCR approach among E.coli isolates reported that all E. coli strains carried the fimH (100%). Meanwhile, other virulence genes sxt1 and eaeA gene didn ' t detected in any tested E. coli isolates. Conclusion: Coliform bacteria were identified as major bacterial pathogens involved in bovine clinical and subclinical mastitis.