Fernandez Miyakawa M E, Uzal F A
Animal Health Unit, The National Institute of Agricultural Technology, Bariloche, Argentina.
Vet Res Commun. 2003 Apr;27(3):231-41. doi: 10.1023/a:1023348708599.
Clostridium perfringens type D produces enterotoxaemia in goats, sheep and other animals. The disease is caused by C. perfringens epsilon toxin and, while enterotoxaemia in goats is usually characterized by enterocolitis, the disease in sheep is characterized by systemic lesions (such as lung and brain oedema) with minor and inconsistent changes observed in the intestine. A possible explanation for these differences is that epsilon toxin is more promptly absorbed by the ovine than by the caprine intestine. In an attempt to clarify this, we examined the early effects of epsilon toxin on caprine and ovine intestine. Intestinal loop assays were performed to analyse the physiological and morphological changes induced by epsilon toxin in the intestine of these species. Fluid accumulation was observed in caprine and ovine ileum and colon treated with epsilon toxin. Ileal loops from goats treated with epsilon toxin retained sodium and water earlier than ovine ileal loops treated with the same toxin. Histological analysis showed morphological alterations in the colon of both species as early as 2 h after the commencement of epsilon toxin treatment: these changes were more marked in goats than in sheep. No morphological changes were observed in the ileum of either species after 4 h incubation with epsilon toxin. These results suggest that epsilon toxin modifies ion and water transport in the small and the large intestine of goats and sheep through different mechanisms.
D型产气荚膜梭菌可在山羊、绵羊和其他动物中引起肠毒血症。该疾病由产气荚膜梭菌ε毒素引起，虽然山羊的肠毒血症通常以小肠结肠炎为特征，但绵羊的疾病特征是全身性病变（如肺和脑水肿），而在肠道中观察到的变化较小且不一致。这些差异的一个可能解释是，ε毒素在绵羊体内比在山羊体内被肠道吸收得更快。为了阐明这一点，我们研究了ε毒素对山羊和绵羊肠道的早期影响。进行肠襻试验以分析ε毒素在这些物种肠道中诱导的生理和形态变化。在用ε毒素处理的山羊和绵羊回肠及结肠中观察到液体蓄积。用ε毒素处理的山羊回肠襻比用相同毒素处理的绵羊回肠襻更早地保留钠和水。组织学分析显示，在开始用ε毒素处理后2小时，两个物种的结肠均出现形态学改变：山羊的这些变化比绵羊更明显。在用ε毒素孵育4小时后，两个物种的回肠均未观察到形态学变化。这些结果表明，ε毒素通过不同机制改变山羊和绵羊小肠和大肠中的离子和水转运。
