蓝狐多重感染的病原学及主要病原的分子生物学特性

Pathogenic studies on multiplex infection in blue fox and molecular biology of its manin pathogen

2006-2007年期间,山东6地区规模化毛皮动物养殖场出现母狐空怀、流产,幼狐呼吸困难,鼻孔出血,气喘并伴有腹泻、死亡等症状,为探明病因,对发病场进行流行病学调查和送检的236份病料组织进行病原学检查,结果表明造成该病的主要原因是由绿脓杆菌(Pseudomonas aerudinosa)、沙门菌(Salmonella)、大肠杆菌(Escherichiacoli)和普通变形杆菌(Proteus vulgaris)共感染所致。这4种细菌单独感染、二重感染、三重感染和四重感染的平均感染率分别为50%、45.8%、3.8%和0.4%。在分离的4种细菌中以绿脓杆菌的分离率为最高,达到86%,对该病原又进行(G+C)mol%、16SrRNA序列同源性和系统发育分析,构建了包括9株邻近种属细菌在内的系统发育树,其中与绿脓杆菌(AJ249451)同源性最高,为99.2%,进一步确定该病原菌属于假单胞菌属中绿脓杆菌。本研究为目前规模化毛皮动物养殖场蓝狐病的原因提出了新的思路,为疾病的防治提供了依据。

During 2006-2007 a kind of disease appeared in some large-scale fur-animal farms of six regions of Shandong with a symptom of abortion bitches＇s, and dyspnea, pink liquid discharge from nostrils, asthma diarrhea and death of kits. Based on the epidemiology investigation and the pathogenic studies of total tested 236 serum samples, it was showed that the mulitplex infection of Pseudomonas aerudinosa .Salmonella .Escherichla coli and Proteus was the major cause of the disease. According to the statistics data, the average infectious rates to the four bacterias of single.double.triple.quadruple infection were 50% ,45.8% ,3.8% and 0.4% of total tested 236 serum samples respectively the isolation rate of Pseudomonas aerudinosa was the highest among the four bacterias, accountting for 86%. Its G＋C content of DNA is 67.5 %. A phylogenetic tree was constructed by comparing with the validly published 16SrRNA sequences of the related type strains from GenBank,and its 16SrRNA sequences highly matched to Pseudomonas aerudinosa, being than 99.2 %. the pathogen is classified as a member of Pseudomonas aerudinosa. The results provide a useful approach to the cause and an evidence for the prevention and cure of the disease in large-scale fur-animal farms.