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.

中文翻译：

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产生NetF的产气荚膜梭状芽胞杆菌及其相关疾病的犬和小马驹。

A型产气荚膜梭菌在犬急性出血性腹泻综合征和小儿坏死性小肠炎中的作用尚不明确。但是，已经描述了新型产气荚膜梭菌的存在与这些特定的肠疾病之间的高度显着关联。这些新的产毒菌株产生了3种新的推定毒素，它们被命名为NetE，NetF和NetG。尽管没有最终证实，但目前的证据表明，NetF可能是犬急性出血性腹泻综合征和驹坏死性肠炎的主要毒力因子。NetF是一种形成β孔的毒素，与产气荚膜梭菌产生的CPB和NetB毒素属于同一毒素超家族。netF基因编码在接合质粒上，对于netF，还携带另一个推定的毒素基因netE。另外，这些菌株还一致地携带cpe tcp结合质粒，一部分也携带单独的netG tcp结合质粒。netF和netG基因构成具有tcp结合质粒的致病基因座的所有特征的基因座的一部分。netF阳性分离株起源于克隆，分为两个进化枝。狗或小马驹的疾病可能与进化枝有关。因此，这些是具有独特毒力相关特征的菌株，与2种动物的严重肠道疾病的严重，有时甚至致命的病例相关。netF和netG基因构成具有tcp结合质粒的致病基因座的所有特征的基因座的一部分。netF阳性分离株起源于克隆，分为两个进化枝。狗或小马驹的疾病可能与进化枝有关。因此，这些是具有独特毒力相关特征的菌株，与2种动物的严重肠道疾病的严重，有时甚至致命的病例相关。netF和netG基因构成具有tcp结合质粒的致病基因座的所有特征的基因座的一部分。netF阳性分离株起源于克隆，分为两个进化枝。狗或小马驹的疾病可能与进化枝有关。因此，这些是具有独特毒力相关特征的菌株，与2种动物的严重肠道疾病的严重，有时甚至致命的病例相关。