某规模化猪场猪舍环境中猪圆环病毒3型的检测与分析

Detection and Analysis of Porcine Circovirus Type 3 in a Large-scale Swine Farm

猪圆环病毒3型(PCV3)是危害我国养猪业的重要病原之一。为探索猪场环境因子与PCV3传播的相关性,揭示实际生产周期中的PCV3传播规律和环境关键风险控制点,在内蒙古自治区某规模化猪场,筛选5个有临床流行病学意义的猪舍,按照实际生产周期,分3批次共采集75份不同类型的环境样品,利用荧光定量PCR方法进行PCV3检测,分析不同生产阶段在不同类型环境样品中的PCV3分布情况。结果显示:在5个猪舍3批次采集的75份不同类型环境样品中,PCV3阳性率为60.00%;5个猪舍不同类型环境样品,在进猪前3 d检测均为PCV3阴性,在进猪后约15 d检测均为PCV3阳性,4个猪舍在进猪后约30 d检测均为PCV3阳性;5个猪舍的垫子、料槽、风机和漏粪板样品中病毒含量均较高。结果表明:5个猪舍流行的PCV3并非由进猪之前(空舍时期)的环境消毒不彻底所致,而可能与引进猪只的健康状况、生产管理等相关;猪舍内的垫子、料槽、风机和漏粪板等可能是PCV3传播中的关键环境风险控制点。本研究从环境控制的角度,提出了PCV3传播中的关键环境风险控制点,为PCV3感染的精准防控提供了参考。

Porcine circovirus type 3(PCV3)is one of major pathogens threating pig industry.In order to clarify the correlation between environmental factors in swine farms and PCV3 transmission,and to reveal the rules of PCV3 transmission and key environmental risk control points in practical production,75 environmental samples were collected in three batches according to practical production period from 5 pig houses with clinical epidemiological significance in a large-scale swine farm in Inner Mongolia to detect PCV3 by fluorescent quantitative PCR,then the distribution of PCV3 in different kinds of environmental samples in various production stages were analyzed.The results revealed that,for all the environmental samples,the positive rate of PCV3 was 60.00%,negative PCV3 was detected 3 days prior to introduction of new pigs,and positive PCV3 was detected 15 days after introduction.For the samples from 4 pig houses,positive PCV3 was detected 30 days after introduction,and the virus load within the samples of mats,tanks,fans and fecal leakage plates from 5 pig houses was relatively high.In conclusion,PCV3 prevalent in the 5 pig houses might be caused by the health status,production management and other factors of introduced pigs instead of incomplete environmental disinfection prior to introduction(empty period);the mats,tanks,fans and fecal leakage plates in pig houses might be the key environmental risk control points for PCV3 transmission.The key environmental risk control points for PCV3 transmission were proposed based on environmental control in the study,providing a reference for future targeted prevention and control of PCV3 infection.