NetF-producing Clostridium perfringens and its associated diseases in dogs and foals

• Published in: Journal of veterinary diagnostic investigation Vol. 32; no. 2; pp. 230 - 238
• Main Authors: Mehdizadeh Gohari, Iman, Unterer, Stefan, Whitehead, Ashley E., Prescott, John F.
• Format: Journal Article
• Language: English
• Published: Los Angeles, CA SAGE Publications 01.03.2020
• Subjects: Animals; Clostridium Infections - diagnosis; Clostridium Infections - microbiology; Clostridium Infections - veterinary; Clostridium perfringens - physiology; Diarrhea - diagnosis; Diarrhea - microbiology; Diarrhea - veterinary; Dog Diseases - diagnosis; Dog Diseases - microbiology; Dogs; Enteritis - diagnosis; Enteritis - microbiology; Enteritis - veterinary; Focus Issue; Horse Diseases - diagnosis; Horse Diseases - microbiology; Horses; Necrosis - diagnosis; Necrosis - microbiology; Necrosis - veterinary; dogs; enteric disease; necrotizing enteritis; NetF; Clostridium perfringens; foals; pore-forming toxin
• ISSN: 1040-6387; 1943-4936
• DOI: 10.1177/1040638720904714

The role of type A Clostridium perfringens in canine acute hemorrhagic diarrhea syndrome and foal necrotizing enteritis is poorly characterized. However, a highly significant association between the presence of novel toxigenic C. perfringens and these specific enteric diseases has been described. These novel toxigenic strains produce 3 novel putative toxins, which have been designated NetE, NetF, and NetG. Although not conclusively demonstrated, current evidence suggests that NetF is likely the major virulence factor in strains responsible for canine acute hemorrhagic diarrhea syndrome and foal necrotizing enteritis. NetF is a beta–pore-forming toxin that belongs to the same toxin superfamily as CPB and NetB toxins produced by C. perfringens. The netF gene is encoded on a conjugative plasmid that, in the case of netF, also carries another putative toxin gene, netE. In addition, these strains consistently also carry a cpe tcp-conjugative plasmid, and a proportion also carry a separate netG tcp-conjugative plasmid. The netF and netG genes form part of a locus with all the features of the pathogenicity loci of tcp-conjugative plasmids. The netF-positive isolates are clonal in origin and fall into 2 clades. Disease in dogs or foals can be associated with either clade. Thus, these are strains with unique virulence-associated characteristics associated with serious and sometimes fatal cases of important enteric diseases in 2 animal species.