Vol. 12, Issue 3 (2023)

Author(s):
Saritha Baby, Chintu Ravishankar, Koshy John, M Mini, Vinu David P and Ajithkumar S

Abstract:
Neonatal calf diarrhoea (NCD) is a major problem faced by the livestock farmers world-wide and calves below one month of age are especially prone to this condition. The condition can be caused by infectious agents such as bacteria, viruses and protozoa. A study was conducted to phylogroup Escherichia coli isolates obtained from cases of NCD and to detect the presence of fimbrial genes in them. For this, a total of 120 faecal samples were collected from diarrhoeic calves below 3 months of age. E. coli was isolated from 101 (84.17%) samples. The isolates were phylogrouped on the basis of results of quadruplex polymerase chain reaction (PCR). All the phylogroups except B2 were detected during the analysis. The maximum number of E. coli isolates (27.72%) belonged to the B1 phylogroup which normally contained strains of low virulence. Isolates belonging to Group A (18.81%), Group C (4.95%), Group D(14.85%), Group E(11.88%), Group F(0.9%) and Clade I (0.9%) were also obtained. When the presence of fimbrial genes F5/F41/F17 was tested by PCR, it was observed that 10 out of 62 isolates (16.13%) were positive for F17 gene. None of the samples were positive for F5 or F41 genes. All the isolates in which F17 genes were detected were from animals above one week of age. The results of the study give valuable information about the type of E. coli and fimbria associated with NCD.