Gholamiandehkordi Ahmad R, Timbermont Leen, Lanckriet Anouk, Van Den Broeck Wim, Pedersen Karl, Dewulf Jeroen, Pasmans Frank, Haesebrouck Freddy, Ducatelle Richard, Van Immerseel Filip
Research Group Veterinary Public Health and Zoonoses, Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
Avian Pathol. 2007 Oct;36(5):375-82. doi: 10.1080/03079450701589118.
Currently Clostridium perfringens-induced necrotic enteritis is a major problem in broiler flocks. In the present study, broilers were inoculated with a combination of Eimeria maxima or overdose coccidial vaccine (one inoculation) with C. perfringens (repeated inoculations). Single C. perfringens, E. maxima or an overdose of live coccidial vaccine inoculations did not result in grossly visible necrotic gut lesions, while combined inoculation resulted in typical necrotic lesions at approximately 4 days after inoculations with C. perfringens in approximately one-half of the inoculated animals. Semi-quantitative histological lesion scoring was done to evaluate gut damage in gut sections of animals in which no gross necrotic lesions were detected. This included scoring of hyperaemia, haemorrhages, the amount of red blood cells and protein precipitate in the lumen, villus fusion and epithelial defects. The villus length and the villus length/crypt depth ratio were also analysed. This approach proved to be discriminative between single E. maxima infection, overdose of coccidial vaccine or C. perfringens inoculations and the non-inoculated control group, and between the double-inoculated and single-inoculated groups. In general, the highest histological scores for gut lesions were observed in the double-inoculated groups, but the single-inoculated groups had higher scores than the control group. It was concluded that oral inoculation of broilers with an overdose of live coccidial vaccine in combination with multiple oral C. perfringens inoculations is a suitable model for necrotic enteritis without inducing mortality of the animals. C. perfringens and Eimeria act synergistically in inducing grossly visible gut damage.
目前，产气荚膜梭菌引起的坏死性肠炎是肉鸡群中的一个主要问题。在本研究中，给肉鸡接种了巨型艾美耳球虫或过量球虫疫苗（一次接种）与产气荚膜梭菌（重复接种）的组合。单独接种产气荚膜梭菌、巨型艾美耳球虫或过量的活球虫疫苗均未导致明显可见的肠道坏死病变，而联合接种在约一半接种产气荚膜梭菌的动物中，接种后约4天导致典型的坏死病变。对未检测到明显坏死病变的动物肠道切片进行半定量组织学病变评分，以评估肠道损伤。这包括对充血、出血、肠腔内红细胞数量和蛋白质沉淀、绒毛融合和上皮缺陷进行评分。还分析了绒毛长度和绒毛长度/隐窝深度比。这种方法被证明能够区分单独的巨型艾美耳球虫感染、过量球虫疫苗接种或产气荚膜梭菌接种与未接种的对照组，以及联合接种组和单独接种组。一般来说，联合接种组的肠道病变组织学评分最高，但单独接种组的评分高于对照组。得出的结论是，给肉鸡口服过量的活球虫疫苗并联合多次口服产气荚膜梭菌是一种适合的坏死性肠炎模型，且不会导致动物死亡。产气荚膜梭菌和艾美耳球虫在诱导明显可见的肠道损伤方面具有协同作用。
