云南红河州猪繁殖障碍综合征病因研究

Etiological studies on Reproductive Disorder Syndrome of pigs in Honghe Prefectrue,Yunnan Province

针对红河州猪繁殖障碍综合征危害日趋严重的现象,进行了该病的流行病学、病原学、人工感染及免疫试验。结果表明,种公猪发病率为23.77%、妊娠母猪发病率为41.38%,仔猪死亡率为19.94%、流产率11.19%、死胎率47.96%、弱仔率31.78%;血清学调查阳性检出率分别为猪瘟(CSF)1.1%、细小病毒(PPV)43.97%、鹦鹉热衣原体(CP)36.98%、伪狂犬病毒(PRV)24.6%、乙型脑炎(JEV)20.9%、弓形虫(Tg)14.66%、蓝耳病病毒(PRRSV)11.5%、猪圆环病毒(PCV)7.2%、布鲁氏菌(Br)2.44%。其中单一感染占39.6%,混合感染占35.6%。从死亡新生仔猪和流产胎儿的脑及内脏中分离获得PPV、PRV、CP各2株病原,经细胞传代,鸡胚传代,毒价测定、形态观察、动物感染试验和应用PCR技术等鉴定,确证为伪狂犬、细小病毒病、衣原体三种。应用猪伪狂犬、细小病毒病、衣原体三种疫苗免疫注射,使本地区猪群的受胎率由92.7%提高到99.5%,妊娠母猪发病率从31.43%下降到0.77%,初生乳猪发病死亡率从24.9%下降到0.27%。调查研究表明,近年来引起红河州地区猪繁殖障碍综合征广泛流行的主要病因是PPV、PRV、CP三种病原单一或混合感染所致,而且动物感染试验证实是PPV、PRV、CP是造成猪繁殖障碍病的主要病原。

The epidemiological investigations, etiological tests, artifitial infection tests and immunization tests were carried out in order to reveal the causes for serious prevalence of reproductive disorder syndrome in pigs recently in Honghe region of Yunnan province. The results showed that the morbidity was 23.77% for breeding boars, for 41.38% pregnant sows, and the piglet mortality in perinatal period reached 19.94%, the abortion rate of infected pregnant sows was 11.19%, stillbirth 47.96%, weak babies 31.78%. Specimens were sampled from pig herds which had not been inoculated with any vaccines for serologic investigations, resulting in classical swine fever virus （CSF） 1.1%, porcine parvovirus （PPV） 43.97%, Chlamydia psittaci （CP） 36.98%, pseudorabies virus （PRV） 24.6%, Japanese encephalitis virus （JEV） 20.9%, Toxoplasma gondii （Tg） 14.66%, porcine reproductive and respiratory syndrome virus （PRRSV） 11.5%, porcine circovirus （PCV） 7.2%, and Brucella sp （Br） 2.44%, with 39.6% single agent infection and 35.6% mixed infection.Two strains each of PPV, CP and PRV were isolated from died newborn piglets and aborted fetus respectively, and detected and identified by means of PCR. The laboratory animals were artificially infected with the isolated agents resulting in same symptoms as the field cases.After pig herds in this region were inoculated with PPV vaccine, CP vaccine and PRV vaccine respectively, the pregnant rate was increased from 92.7% to 99.5%, the morbidly of piglets was reduced from 31.43% to 0.77%, and the mortality of piglets was reduced from 24.9% to 0.27%. The study confirmed that porcine parvovirus, Chlamydia psittaci and pseudorabies virus were the major pathogens causing swine reproductive disorder syndromes by means of single or multiple infections.