The association of Clostridium perfringens with foal diarrhoea

Several case reports of i>Clostridium perjringens</i> involvement in equine enteric disease have not identified the prevalence and statistical association of these bacteria with foal diarrhoea. Each of five methods which favoured the recovery of <i>C. perjringens</i> in different physiological states were chosen to improve the sensitivity of isolation in a survey of foal diarrhoea for <i>C. perjringens</i> and other pathogens. <i>C. perjringens</i> was significantly associated with foal diarrhoea (isolated from 57% of 421 scouring anjmals but from only 33% of 222 controls; odds ratio 7.4; p<0.001 by multivariate analysis); it was also associated with fatal diarrhoea (odds ratio 2.7; p=0.047). Rotavirus, <i>Cryptosporidium sp.</i> and large numbers of <i>Strongyloides westeri</i> were the only other pathogens associated with diarrhoea although they were less prevalent than <i>C. perjringens; Salmonella sp.</i> was the only other pathogen associated with fatal diarrhoea. <br></br><br></br>Enterotoxin production was detected by reverse passive latex agglutination test (RPLA) amongst isolates of <i>C. perjringens</i> from scouring and healthy foals. The enterotoxin gene from an equine strain was cloned and its sequence was essentially identical to that published for a human isolate. Less than 5% of <i>C. perjringens</i> isolated from scouring foals and 0.5% from controls were positive for the enterotoxin gene by polymerase chain reaction (PCR) (odds ratio 19.1; p<0.005). Presence of the enterotoxin gene was confirmed in representative isolates with a gene probe of chromosomal DNA and PCR product as well as neutralisation of cytotoxicity by antitoxin. Enterotoxigenicity of half ofRPLA positive isolates could not be confirmed in this way. <br></br><br></br>Enterotoxigenic <i>C. perjringens</i> were a probable cause of foal diarrhoea. However, a greater proportion of the disease was associated with non-enterotoxigenic <i>C. perjringens</i>. There is now a need to identify molecular differences between non-enterotoxigenic <i>C. perjringens</i> strains from scouring and healthy foals which might be associated with pathogenicity.

Name dc:type.qualificationname

phd

Level dc:type.qualificationlevel

doctoral

Grantor dc:publisher.institution

The Open University

Year dc:date.issued

1995

Author dc:creator

• Netherwood, Trudy

Language dc:language

en