Search Filter
- Publications
- Abstract of Theses and Dissertations
- Database
- Isolation, Identification, and Detection of Enterotoxigenic...
Isolation, Identification, and Detection of Enterotoxigenic Escherichia Coli from Dairy Calves in Hanoi City and Hatay Province, Vietnam
Thesis Abstract:
Rectal fecal samples of diarrheic and non-diarrheic dairy calves (90 each) from 10 selected farms in Hanoi City and Hatay province, Vietnam, were cultured to detect enterotoxigenic Escherichia coli (ETEC) which possess pilus antigen and produce enterotoxin. All calves, less than 30 days old and of both sexes, came from unvaccinated and untreated dams. Based on colonial morphology and reaction to biochemical tests, E. coli were isolated from all animals.
Slide coaglutination and infant mouse tests revealed that 34.44 percent of diarrheic calves had ETEC; only 10 percent of non-diarrheic calves harbored these strains. This study only detected ST because bovine isolates of ETEC do not produce LT. Enteroxin-producing E. coli possessing FS pilus antigen were detected at a higher rate in diarrheic (21 %) than non-diarrheic calves (7%). Similarly, ETEC containing F41 pilus antigen were found in 8.89 percent of the non-diarrheic groups. Only one calf each in the diarrheic group and in non-diarrheic group harbored E.coli bearing F6 antigen and producing ST. Three (3.33%) diarrheic calves harbored both FS and F41 producing enterotoxin E. coli. In this study. ETEC containing FS, F41, and F6 pili antigens were found in calves.