3种非猪瘟病毒单独或混合感染对猪瘟弱毒疫苗免疫效力的影响

将 2 0头 9月龄左右猪瘟、伪狂犬、猪繁殖与呼吸障碍综合征抗原、抗体阴性猪分成 6组 ,分别利用猪细小病毒(PPV)、猪伪狂犬病毒 (PRV)和猪繁殖与呼吸障碍综合征病毒 (PRRSV)单独或混合感染。 7d后连同对照猪 4头 ,免疫接种猪瘟兔化弱毒疫苗 (HCL V) ,13d后连同 4头阴性对照猪一起攻击猪瘟石门强毒。整个试验期间分别每天测温 ,观察临床症状 ,每周采集扁桃体和血样做各种病毒抗原及抗体检测。结果表明 ,非猪瘟病毒感染 7d后 ,所有各组猪均从体内检测到了相应感染的病原 ,表明 3种非猪瘟病毒感染成功。在攻击猪瘟石门强毒后 2周 ,感染了非猪瘟病毒后接种 HCL V疫苗的 4个免疫组 12头猪除 1头外 ,11头全为猪瘟病毒 (HCV)抗原检测阳性 ,且多呈强阳性 ;而单一 HCL V疫苗免疫组在猪瘟强毒攻击后检测不到 HCV;所有 HCL V疫苗免疫猪均存活 ,而非免疫对照组 4头猪全部在攻毒 16 d内死亡。

Effect on Immune Efficacy of HCLV by Infection of Three Sorts of Non-HCV Viruses Respectively or Together

Twenty nine-month old pigs,failed to detect the hog cholera virus(HCV),porcine parvovirus(PPV),pesudorabides virus(PRV) and porcine reproductiive and respiratory syndrome virus(PRRSV) and correspondant antibodies,were divided into six groups,inoculated with PPV,PRV and PRRSV respectively or together.Seven days later,the twenty pigs and other four controls were inoculated with hog cholera lapinizated virus(HCLV),thirteen days later,challenged against SiMen virulent stain of HCV.During the whole test,temperatures and clinical signs were observed daily,and tonsils and blood samples were collected weekly,then detected by antigen and antibody test respectively.The results indicated:All pigs in all the groups were experimentally infected with PPV,PRV and PRRSV,seven days later,correspondent viruses were detected,indicating the experimental infection of the three sorts of non-HCV viruses were successful.In two weeks after being challenged against SiMen virulent strain of HCV,eleven of twelve pigs in four immune groups were detected as HCV positive.However groups vaccinated only by HCLV failed to detect HCV antigen.All pigs vaccinated with HCLV survived.Whereas the control group without vaccination died after being challenged with HCV in sixteen days.