新疆部分地区规模化猪场猪囊等孢球虫的套式PCR检测及感染情况分析

目的]了解新疆部分地区规模化猪场猪囊等孢球虫的感染情况。方法]基于猪囊等孢球虫SSU rDNA基因位点设计引物，采用套式PCR法对采集自新疆7个规模化猪场的801份猪新鲜粪便DNA样本进行检测；对不同养殖场、不同年龄段猪的猪囊等孢球虫感染率进行比较分析，对获得的SSU rDNA序列进行比对分析并构建种系发育进化树。结果]调查猪场中猪囊等孢球虫感染率为5.74%（46/801），以沙雅县养殖场感染率最高，为14.00%（14/100），不同养殖场猪囊等孢球虫感染率统计学差异极显著（χ²=27.081，df=6，P<0.01）。未断奶仔猪、断奶仔猪、育肥猪和母猪的猪囊等孢球虫感染率分别为14.79%（25/169）、5.78%（13/225）、2.31%（4/173）和1.71%（4/234），不同年龄段猪的猪囊等孢球虫感染率统计学差异极显著（χ²=36.366，df=3，P<0.01）。序列比对和种系发育分析显示，获得的46条猪源囊等孢球虫SSU rDNA序列与安徽省凤阳县猪源猪囊等孢球虫分离株（GenBank登录号：KX808495）SSU rDNA序列的同源性均为100%，处于同一个亚群。结论]新疆部分地区规模化猪场猪囊等孢球虫感染较常见，应加强检测和防治工作。

Nested PCR-based Detection and Infection Situation Analysis of Cystoisospora suis in Large-scale Pig Farms in Partial Areas of Xinjiang，China

Objective] The present study aimed to understand the situation of Cystoisospora suis infection in large-scale pig farms in partial areas of Xinjiang, China. Method] Primers targeting the SSU rDNA gene locus of Cystoisospora suis were designed. A total of 801 DNA samples extracted from fresh pig feces collected from 7 large-scale pig farms in Xinjiang were screened for the presence of target gene by using nested PCR assay. Cystoisospora suis infection rates in pigs of various farms and ages were statistically assessed. The obtained SSU rDNA sequences were bioinformatically compared and analyzed, and a phylogenetic tree was constructed. Result] The general infection rate of Cystoisospora suis in the surveyed pig farms was 5.74% （46/801）, and the highest infection rate （14.00%, 14/100） was observed in the pig farm in Shaya County. Cystoisospora suis infection rates among various pig farms were statistically significantly （χ²=27.081, df=6, P<0.01） different. In unweaned piglets, weaned piglets, fattening pigs and sows, the Cystoisospora suis infection rates were 14.79% （25/169）, 5.78% （13/225）, 2.31% （4/173） and 1.71% （4/234）, respectively. Cystoisospora suis infection rates in pigs of various ages were statistically significantly （χ²=36.366，df=3，P<0.01） different. In sequence comparison and phylogenetic analysis, the SSU rDNA sequences （n=46） of Cystoisospora suis obtained in this study had 100% homology with the SSU rDNA sequence of a Cystoisospora suis isolate from Fengyang County, Anhui Province （GenBank accession number: KX808495）, and they were genetically categorized in the same subgroup. Conclusion] Infections caused by Cystoisospora suis were common in large-scale pig farms in partial areas of Xinjiang, so detection and prevention should be strengthened.