Detection of heat-stable and heat-labile enterotoxin genes of Escherichia coli in diarrhoeic faecal samples of mithun (Bos frontalis) calves by polymerase chain reaction.
OBJECTIVE
To find out the prevalence of different serogroups of Escherichia coli (E. coli) and to detect heat-stable (ST) and heat-labile (LT) enterotoxin genes of enterotoxigenic E. coli (ETEC) from the faeces of mithun calves with diarrhoea.


RESULTS
Faecal samples obtained from 65 diarrhoeic mithun calves of under 2 months of age were examined for E. coli using polymerase chain reaction (PCR). Fifty-four E. coli isolates were obtained from those samples, which belonged to 38 different serogroups. Out of 54 isolates tested by PCR, two isolates (3.70%) belonging to serogroups O26 and O55 were found to possess gene that code for ST enterotoxin and one isolate (1.85%) belonging to serogroup O125 was found to carry LT enterotoxin gene.


CONCLUSIONS
Escherichia coli isolates from diarrhoeic mithun calves were found to possess ST and LT enterotoxin genes, which are designated as ETEC, and these isolates can be detected through PCR using specific primers.


CONCLUSIONS
This study reports the isolation of ETEC possessing ST and LT enterotoxin genes for the first time and ETEC could be a cause of diarrhoea in mithun calves leading to calf mortality.
Rajkhowa
S
S
Division of Animal Health, National Research Centre on Pig, Indian Council of Agricultural Research, Rani, Guwahati, Assam, India. s_rajkhowa@lycos.com
Hussain
I
I
Rajkhowa
C
C
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000382:microbiology; D004269:DNA, Bacterial / Q000235:genetics; D003967:Diarrhea / Q000209:etiology / Q000382:microbiology / Q000662:veterinary; D054307:Enterotoxigenic Escherichia coli / Q000145:classification / Q000235:genetics*; D004768:Enterotoxins / Q000032:analysis / Q000235:genetics*; D004927:Escherichia coli Infections / Q000382:microbiology / Q000662:veterinary*; D005243:Feces / Q000382:microbiology*; D005798:Genes, Bacterial; D016133:Polymerase Chain Reaction / Q000379:methods / Q000662:veterinary; D012703:Serotyping
D004269:DNA, Bacterial; D004768:Enterotoxins