摘要
本试验用猪繁殖-呼吸综合征(PRRS)活疫苗和国内分离的PRRS强毒CH-1a株接种PRRS阴性的断奶仔猪,分别在接种后的3、7、14d各剖杀1头,取各脏器分别做冰冻切片和病理切片观察。用间接免疫荧光法检测各脏器PRRS病毒的分布。结果表明,PRRS活疫苗在免疫初期,抗原主要分布在脾脏、淋巴结,其次是肾脏和肺脏,少见于肝脏和心脏,第14d时在脾、淋巴结和肾脏有一定量的抗原,而肺脏相比则数量很少,肝脏和心脏未检到PRRS病毒抗原的存在,表明接种PRRS活疫苗随着时间的推移抗原分布呈下降趋势。而强毒抗原分布以脾脏最多,依次是肾脏、肺脏、淋巴结、肝脏、心脏,接种后第14d仍能在各脏器检到PRRS病毒抗原。病理组织学检测结果表明,活疫苗产生以下颌淋巴结、脾脏增生为特征的免疫应答,组织损伤轻微,对肺的病变较少,且仔猪生长良好。强毒则引起以大面积的肺泡隔增宽为特点的间质性肺炎和微循环障碍的病理变化,淋巴小结、脾脏滤泡发生崩解与周围界限不清,个别淋巴细胞核浓缩,组织损伤严重。本试验表明弱毒疫苗对仔猪是安全的。
In this study, a modified live vaccine （MLV） against porcine reproductive and respiratory syndrome virus （PRRSV） and virulent CH-Ia strain were used to inoculate PRRSV-negative weaned piglets. One piglet was euthanized 3, 7 and 14 days post-inoculation （dpi） in each group, and tissue samples were collected and subjected to histopathological testing. The distributions of PRRSV antigens were tested by indirect immunofiuorescent assays （IFA） after inoculation. It was found many antigens were distributed in spleens, lymph nodes, followed by kidneys and lungs, and seldom in the livers and hearts early after inoculation with MLV. On 14 dpi, fewer antigens were found in spleens, lymph nodes and kidneys, even fewer in lungs, and undetectable in livers and hearts. This indicated that the MLV virus was gradually removed in tissues after inculcation. However, in pigs inoculated with CH-la strain, the virus antigens were distributed predominantly in spleens, followed by kidneys, lungs, lymph nodes, livers and hearts,and the virus antigens could be which were characterized by proliferation in lymph nodes and spleens, and mild lesions were detected in many tissues 14 dpi. Histopathology showed that the MLV elicited immune responsesinduced in tissues especially in lungs. On the contrary, the virulent CH-1a strain induced massive interstitial pneumonia and micro-vascular lesions, collapsed lymph nodes and spleen follicles with faint boundaries and occasional condensed lymphocyte nucleoli, which showed that tissues were severely damaged. We conclude the MLV is safe for piglets.
出处
《中国预防兽医学报》
CAS
CSCD
北大核心
2006年第3期341-343,346,共4页
Chinese Journal of Preventive Veterinary Medicine
关键词
猪繁殖-呼吸综合征
活疫苗
安全性
porcine reproductive and respiratory syndrome
live vaccine
safety
