摘要
为了确证我国标准速发型新城疫强毒株F48E9致病性的细化分型,分别采用泄殖腔涂抹、泄殖腔注射、点眼滴鼻和静脉注射4种感染途径,用高、低2种剂量对SPF鸡进行感染,综合分析临床症状和病理变化。结果显示：各组均出现典型神经症状,并且伴随呼吸道症状和下痢,其中高剂量组尤其是静脉注射途径,病程较短,出现明显神经症状后1-2 h死亡,病理变化不明显;低剂量组发病平缓,神经症状呈明显的渐进性,其中以点眼滴鼻途径最为明显;各感染途径剖检观察到明显的脑部及肠道出血;综合分析判定F48E9株为嗜神经型速发型强毒。同时,针对强毒株致病性的细化分型,建议采取点眼滴鼻途径和低剂量方式,综合分析临床症状和病理变化进行鉴定。对速发型新城疫病毒的细化分型鉴定能够进一步为新城疫的鉴别诊断,病毒的组织嗜性、致病机理研究提供重要的基础依据。
The strain F48 E9 of the Newcastle disease virus is a standard velogenic virus in China,but there is little report about its refined pathotypic classification. In order to verify the classification,specific pathogen-free chickens were infected with the F48 E9 strain at high and low doses through cloacal swab,cloacal injection,ocular-nasal and intravenous routes,respectively. Then,clinical signs and pathogenic lesions were evaluated. The results showed that all the experimental groups presented typical neurological signs accompanied with respiratory symptoms and slight diarrhea. In the high dose groups,especially by the intravenous route,the course of disease was short and the birds died rapidly one to two hours after neurological symptoms appeared,but the pathological changes in them were not obvious. In the low dose groups,mild neurological signs were gradually progressing and most obviously in the ocular-nasal route. The hemorrhage in the brains and intestines was evidently observed in all the inoculation routes. In conclusion,the pathotype of F48E9 strain is velogenic and neurotropic. The ocular-nasal route and low dose for virus infection are proposed to assess clinical signs and pathogenic lesions for identifying the refined pathotype of velogenic virus. This study may provide an important basis for differential diagnosis,tissue tropism and pathogenesis of the Newcastle disease virus.
出处
《畜牧与兽医》
北大核心
2018年第2期91-96,共6页
Animal Husbandry & Veterinary Medicine
基金
国家自然科学基金项目(31572533)
