摘要
【目的】为阐明高致病性猪繁殖与呼吸综合征病毒(HP-PRRSV)和猪圆环病毒2型(PCV2)的协同致病作用,澄清两种病毒不同时间顺序共感染与其协同致病力之间的关系。【方法】选取35日龄阴性健康猪30头,随机分6组,PCV2/HP-PRRSV顺序共感染组、HP-PRRSV/PCV2顺序共感染组、HP-PRRSV+PCV2同时共感染组、HP-PRRSV感染组、PCV2感染组、未接种对照组。感染后每天测量体温、观察临床症状,每周称量体重、采血。用流式细胞仪检测血液中的CD3+CD4+CD8-、CD3+CD4-CD8+、γδT、NK细胞及粒细胞和单核细胞变化;免疫过氧化物酶单层细胞试验(IPMA)检测这两种病毒抗体变化;用ELISA法检测血清中IFN-γ、TNF-α、IL-10、IL-2、GM-CSF细胞因子变化;用荧光定量PCR法检测血清和组织中病毒载量。对各组试验猪进行组织病理学观察。【结果】HP-PRRSV/PCV2顺序共感染组临床症状最严重,死亡率达60%;组织和血清中病毒载量显著高于其它组,抗体滴度明显低于其它组;淋巴细胞亚群及细胞因子(尤以TNF-α)变化也最为明显。【结论】HP-PRRSV和PCV2之间存在协同致病作用,且猪群先感染HP-PRRSV后感染PCV2可明显提高猪群发病率和死亡率。本研究对临床HP-PRRSV和PCV2的综合防制提供科学依据。
[Objective] The purpose is to study the synergetic pathogenic effect between highly pathogenic porcine reproductive and respiratory syndrome virus （HP-PRRSV） and porcine cirovirus type 2 （PCV2）, and to clarify the relation of ordinal co-infection and synergetic pathogenicity. [Method] Thirty 35-day-old piglets were randomly selected and separated into 6 groups which designated PCV2/HP-PRRSV ordinal co-infection group, HP-PRRSV/PCV2 ordinal co-infection group, HP-PRRSV＋PCV2 simultaneous co-infection group, HP-PRRSV infection group, PCV2 infection group and control group, respectively. Clinical symptom and temperature were recorded everyday post-inoculation, meanwhile, weighing body weight and collecting blood samples. Variations of CD3＋CD4＋CD8, CD3＋CD4-CD8＋, γδT, NK, granulocyte and mononuclear cell were determined by flow cytometry. Two kinds of antibodies against HP-PRRSV and PCV2 were quantified by immunoperoxidase monolayer assay （IPMA）. Concentrations of IFN-3,, TNF-（t, IL-10, IL-2, GM-CSF in serum were determined by ELISA. Pathological changes were observed through making pathological section for different organs. [ Result ] All the findings suggest that the pathogenicity of HP-PRRSV/PCV2 ordinal co-infection is conspicuously more severe than other testing groups. Mortality of this group is 60% surprisingly. Virus load in body is the highest while antibodies level is the lowest. Variation of imrnunocyte subgroups and cytokines （especially TNF-α） is the most conspicuous. [Conclusion] There is a synergetic pathogenicity of co-infection of pigs with HP-PRRSV and PCV2. If HP-PRRSV infecting precedes PCV2, the morbility and mortality will be conspicuously enhanced. This study has provided a scientific proof to control the two viruses.
出处
《中国农业科学》
CAS
CSCD
北大核心
2012年第18期3859-3872,共14页
Scientia Agricultura Sinica
基金
国家自然科学基金项目(30871859)
农业科技成果转化基金项目(2010GB23260563)
关键词
高致病性猪繁殖与呼吸综合征病毒
猪圆环病毒2型
共感染
协同致病性
highly pathogenic porcine reproductive and respiratory syndrome virus
porcine eirovirus type 2
co-infection
synergetic pathogenicity
