Spagnuolo-Weaver M, Allan G M, Kennedy S, Foster J C, Adair B M
Institute of Microbiology, Federal University of Rio de Janeiro, Brazil.
J Vet Diagn Invest. 1997 Jul;9(3):287-97. doi: 10.1177/104063879700900310.
The distribution of cytopathic and noncytopathic biotypes of bovine viral diarrhea virus (BVDV) in the tissues of colostrum-fed and colostrum-deprived calves was investigated. Colostrum-fed (group A) and colostrum-deprived (group B) calves were experimentally infected with the BVDV isolate 80/1, which contains both BVDV biotypes. Colostrum-deprived calves were also experimentally infected with a noncytopathic BVDV (group C) or with a cytopathic BVDV (group D) cloned from the 80/1 isolate. All calves were sequentially euthanized, and a wide range of tissue samples were processed for immunofluorescent and virus isolation studies. In group A, consistent immunofluorescent staining for BVDV was detected in vascular smooth muscle of numerous blood vessels in the tissues examined, mainly at 11 and 13 days postinoculation. A predominance of samples containing cytopathic BVDV was observed in the calves of this group, following virus isolation studies. Both cytopathic and noncytopathic BVDV were detected/recovered from a larger range of specimens in the calves in group B than from the calves in group A. In the calves in all the experimental groups, large amounts of BVDV antigen were detected mainly in tissue samples from the lymphoid and gastrointestinal systems, whereas only minimal amounts of BVDV were detected in the respiratory tract. Abundant noncytopathic BVDV antigen was also detected in pituitary gland and in Langerhans islets in pancreases of colostrum-deprived calves infected with the cloned noncytopathic BVDV. Noncytopathic BVDV was isolated from a wider range of tissues from calves in group C than in the colostrum-deprived calves infected with both BVDV biotypes. A cytopathic BVDV was isolated/detected in retropharyngeal, mesenteric, and abomasal lymph nodes and in thymus of 2 calves in group C. Cytopathic BVDV was detected/isolated mainly from mesenteric lymph nodes and Peyer's patches of the calves in group D.
研究了牛病毒性腹泻病毒（BVDV）的致细胞病变型和非致细胞病变型生物型在初乳喂养和未喂初乳犊牛组织中的分布情况。初乳喂养（A组）和未喂初乳（B组）的犊牛经实验感染了BVDV分离株80/1，该分离株包含两种BVDV生物型。未喂初乳的犊牛还经实验感染了从80/1分离株克隆的非致细胞病变型BVDV（C组）或致细胞病变型BVDV（D组）。所有犊牛均按顺序实施安乐死，并对多种组织样本进行处理，用于免疫荧光和病毒分离研究。在A组中，在接种后11天和13天，在所检查组织的众多血管的血管平滑肌中检测到一致的BVDV免疫荧光染色。病毒分离研究后，在该组犊牛中观察到含有致细胞病变型BVDV的样本占优势。与A组犊牛相比，B组犊牛中从更大范围的标本中检测到/分离出了致细胞病变型和非致细胞病变型BVDV。在所有实验组的犊牛中，大量BVDV抗原主要在淋巴和胃肠系统的组织样本中检测到，而在呼吸道中仅检测到极少量BVDV。在感染克隆的非致细胞病变型BVDV的未喂初乳犊牛的胰腺垂体和胰岛中也检测到大量非致细胞病变型BVDV抗原。与感染两种BVDV生物型的未喂初乳犊牛相比，从C组犊牛更广泛的组织中分离出了非致细胞病变型BVDV。在C组的2头犊牛的咽后、肠系膜和皱胃淋巴结以及胸腺中检测到/分离出了致细胞病变型BVDV。致细胞病变型BVDV主要从D组犊牛的肠系膜淋巴结和派伊尔结中检测到/分离出。
