Department of Veterinary Science and Microbiology, University of Arizona, 1117 E. Lowell St., Tucson, AZ 85721, USA.
Anaerobe. 2010 Jun;16(3):289-92. doi: 10.1016/j.anaerobe.2010.02.006. Epub 2010 Mar 1.
Clostridium perfringens type A is the most common cause of poultry necrotic enteritis (NE). Of the four "major" toxins, type A strains produce only alpha toxin (CPA), which has long been considered a major factor in pathogenesis of NE. We investigated the virulence for poultry of type A strains from a variety of enteric sources. Newly-hatched CornishxRock chicks were fed a low protein diet for one week, a high protein diet for a second week, and then challenged with log-phase cultures of C. perfringens, mixed 3:4 (v/v) with high protein feed. Strain JGS4143 [genotype A, beta2 positive (cpb2(pos)), from a field case of NE] produced gross lesions compatible with NE in >85% of challenged birds. However, strains JGS1714 (enterotoxigenic genotype A, cpb2(pos), human food poisoning), JGS1936 (genotype A, cpb2(neg), bovine neonatal enteritis), JGS4142 (genotype A, cpb2(pos), bovine jejunal hemorrhage syndrome), JGS1473 (genotype A, cpb2(pos), chicken normal flora), JGS1070 (genotype C, cpb2(pos), porcine hemorrhagic enteritis), JGS1882 (genotype A, cpb2(pos), porcine neonatal enteritis), JGS1120 (ATCC 13124, genotype A, cpb2(neg), gas gangrene), JGS4151 (strain 13, genotype A, cpb2(pos), canine), and JGS4303 (SM101, enterotoxigenic genotype A, cpb2(neg), human food poisoning) failed to produce disease. In vivo passage failed to increase virulence of the non-NE strains. NE strains must have specific poultry-associated virulence attributes, such as the recently identified NetB and other factors, which allow for the development of disease.
A 型产气荚膜梭菌是禽类坏死性肠炎（NE）最常见的病因。在这四种“主要”毒素中，A 型菌株仅产生α毒素（CPA），长期以来一直被认为是 NE 发病机制中的主要因素。我们研究了来自各种肠道来源的 A 型菌株对家禽的毒力。新生的科尼什洛克小鸡在一周内喂食低蛋白饮食，第二周喂食高蛋白饮食，然后用 A 型产气荚膜梭菌的对数期培养物挑战，与高蛋白饲料以 3:4（v/v）混合。JGS4143 菌株[基因型 A，β2 阳性（cpb2(pos)），来自 NE 的田间病例]使>85%的受挑战鸡产生与 NE 一致的大体病变。然而，JGS1714 菌株（肠毒素基因型 A，cpb2(pos)，人类食物中毒）、JGS1936 菌株（基因型 A，cpb2(neg)，牛新生肠炎）、JGS4142 菌株（基因型 A，cpb2(pos)，牛空肠出血综合征）、JGS1473 菌株（基因型 A，cpb2(pos)，鸡正常菌群）、JGS1070 菌株（基因型 C，cpb2(pos)，猪出血性肠炎）、JGS1882 菌株（基因型 A，cpb2(pos)，猪新生肠炎）、JGS1120 菌株（ATCC 13124，基因型 A，cpb2(neg)，气性坏疽）、JGS4151 菌株（13 株，基因型 A，cpb2(pos)，犬）和 JGS4303 菌株（SM101，肠毒素基因型 A，cpb2(neg)，人类食物中毒）未能引起疾病。体内传代未能增加非 NE 菌株的毒力。NE 菌株必须具有特定的与家禽相关的毒力属性，例如最近确定的 NetB 和其他因素，这些因素允许疾病的发展。
