Giovanardi Davide, Drigo Ilenia, De Vidi Beatrice, Agnoletti Fabrizio, Viel Laura, Capello Katia, Berto Giacomo, Bano Luca
a Laboratorio Tre Valli , Viale A. Veronesi 5, Verona , Italy.
b Microbiology and Diagnostic Laboratory , Istituto Zooprofilattico Sperimentale delle Venezie , Villorba di Treviso , Italy.
Avian Pathol. 2016 Jun;45(3):376-80. doi: 10.1080/03079457.2016.1160364.
One hundred and six Clostridium perfringens field strains, isolated from diseased turkeys in Italy between 2006 and 2015, were toxinotyped by polymerase chain reaction. Strains were derived from intestines (87), livers (17) and subcutaneous tissues (2). In addition to the four major toxins, strains were also screened for NetB toxin, enterotoxin and beta2 toxin encoding genes. The intestinal gross lesions of turkeys with enteric disorders were statistically studied with respect to the presence of C. perfringens beta2 toxin encoding gene and coccidia in the gut. All the isolates belonged to the toxinotype A and were netB negative. Enterotoxin (cpe) and beta2 toxin (cpb2) encoding genes were detected in two (2.63%) and 76 (71.69%) strains, respectively. Toxinotype results agree with the few published reports concerning the genetic characterization of C. perfringens of turkey origin. On the contrary, the presence of netB and cpb2 genes differs from the results of a previous study where these genes were detected respectively in 6.6% and in 0.5% of the tested strains. Necrotic enteritis in turkeys was not statistically correlated either to the presence of cpb2 gene, or to the synergistic effect operated by coccidia, even though a high percentage of birds with these protozoa in the gut showed necrotic enteritis lesions (64.29%).
对2006年至2015年间从意大利患病火鸡中分离出的106株产气荚膜梭菌田间菌株进行了聚合酶链反应毒素分型。菌株来源于肠道(87株)、肝脏(17株)和皮下组织(2株)。除了四种主要毒素外,还对菌株进行了NetB毒素、肠毒素和β2毒素编码基因的筛选。对患有肠道疾病的火鸡的肠道大体病变,就肠道中产气荚膜梭菌β2毒素编码基因和球虫的存在情况进行了统计学研究。所有分离株均属于A型毒素型,且NetB阴性。分别在两株(2.63%)和76株(71.69%)菌株中检测到肠毒素(cpe)和β2毒素(cpb2)编码基因。毒素分型结果与少数关于火鸡源产气荚膜梭菌基因特征的已发表报告一致。相反,netB和cpb2基因的存在情况与先前一项研究的结果不同,在先前研究中,这些基因分别在6.6%和0.5%的测试菌株中被检测到。火鸡坏死性肠炎与cpb2基因的存在或球虫的协同作用均无统计学相关性,尽管肠道中有这些原生动物的火鸡中有很高比例出现坏死性肠炎病变(64.29%)。