新疆紫泥泉草场绵羊面部湿疹病原真菌的分离鉴定及遗传进化分析

Isolation,identification and genetic evolution analysis of pathogenic fungi from facial eczema in sheep from Ziniquan region,Xinjiang Uygur Autonomous Region

为了了解新疆紫泥泉草场绵羊面部湿疹感染的病原真菌及其遗传进化规律,试验利用R语言结合流行病学方法分析绵羊面部湿疹的世界流行情况,对该病高发地新疆紫泥泉草场中的主要病原真菌进行分离与鉴定、PCR-DGGE分析、序列比对、系统进化树构建和遗传进化分析。结果表明:绵羊面部湿疹主要在温带大陆性气候纬度带流行;样品经分离培养,共鉴定出4种分离率较高的真菌;该草场的优势菌属为皮司霉菌属(Pithomyces sp.)、链格孢菌属(Alternaria sp.)、镰刀菌属(Fusarium sp.)、曲霉菌属(Aspergillus sp.),分离率较高的菌株分别为纸皮司霉菌[Pithomyces chartarum(XJ-Znq)]、链格孢葡萄菌[Alternaria botrytis(XJ-Znq)]、尖孢镰刀菌[Fusarium oxysporum(XJ-Znq)]、黄曲霉菌[Aspergillu flavus(XJ-Znq)];该草场Pithomyces chartarum(XJ-Znq)分离株与同属皮司霉菌属真菌株的同源性高达100%;分离得到的Pithomyces chartarum(XJ-Znq)和Alternariabotrytis(XJ-Znq)序列保守性较好,Fusarium oxysporum(XJ-Znq)和Aspergilluflavus(XJ-Znq)序列单独分支,与同属真菌差异较大。说明新疆紫泥泉草场病原真菌存在一定变异,揭示了绵羊面部湿疹的发病原因。

In order to study which pathogenic fungi mainly caused facial eczema in sheep from Zinniquan region,Xinjiang Uygur Autonomous Region,and their genetic evolutionary pattern,R language combined with epidemiological methods was used to analyze the worldwide prevalence of facial eczema in sheep,and to carry out the isolation and identification,PCR-DGGE analysis,sequence alignment,phylogenetic tree construction and genetic evolutionary analysis on the the main pathogenic fungi from Zinniquan pasture,Xinjiang Uygur Autonomous Region,in which the disease is highly prevalent.The results showed that sheep facial eczema was mainly prevalent in the latitudinal zone of temperate continental climate.The samples were isolated and cultured,and four species of fungi with high isolation rates were identified;the dominant genera in this pasture were Pithomyces sp.,Alternaria sp.,Fusarium sp.,Aspergillus sp..Sequencing alignment showed that the strains with high isolation rate in this pasture were Pithomyces chartarum(XJ-Znq),Alternaria botrytis(XJ-Znq),Fusarium oxysporum(XJ-Znq),Aspergillus flavus(XJ-Znq).The homology between the isolated strain of Pithomyces chartarum and the fungal strain of the same genus Pithomyces chartarum was up to 100%;the sequences of Pithomyces chartarum(XJ-Znq)and Alternaria botrytis(XJ-Znq)were well conserved,and the sequences of Fusarium oxysporum(XJ-Znq)and Aspergillu flavus(XJ-Znq)were separately branched,and differed more from the fungi of the same genus.The results indicated that there was some variation in the pathogenic fungi from Ziniquan pasture,Xinjiang Uygur Autonomous Region,which revealed the pathogenesis of facial eczema in sheep.