Saif L J
Food Animal Health Research Program, Ohio Agricultural Research and Development Centre, Ohio State University, Wooster 44691.
Vet Immunol Immunopathol. 1987 Dec;17(1-4):425-39. doi: 10.1016/0165-2427(87)90159-0.
Unsuckled specific pathogen free calves were inoculated at 3-4 weeks of age, either intranasally (IN) or orally (O) with bovine coronavirus or O plus IN (O/IN) or O with bovine rotavirus. Shedding of virus in nasal or fecal samples, and virus-infected nasal epithelial cells were detected using immunofluorescent staining (IF), ELISA or immune electron microscopy (IEM). Isotype-specific antibody titers in sera, nasal and fecal samples were determined by ELISA. Calves inoculated with coronavirus shed virus in feces and virus was detected in nasal epithelial cells. Nasal shedding persisted longer in IN-inoculated calves than in O-inoculated calves and longer than fecal shedding in both IN and O-inoculated calves. Diarrhea occurred in all calves, but there were no signs of respiratory disease. Calves inoculated with rotavirus had similar patterns of diarrhea and fecal shedding, but generally of shorter duration than in coronavirus-inoculated calves. No nasal shedding of rotavirus was detected. Peak IgM antibody responses, in most calves, were detected in fecal and nasal speciments at 7-10 days post-exposure (DPE), preceeding peak IgA responses which occurred at 10-14 DPE. The nasal antibody responses occurred in all virus-inoculated calves even in the absence of nasal shedding of virus in rotavirus-inoculated calves. Calves inoculated with coronavirus had higher titers of IgM and IgA antibodies in fecal and nasal samples than rotavirus-inoculated calves. In most inoculated calves, maximal titers of IgM or IgA antibodies correlated with the cessation of fecal or nasal virus shedding. A similar sequence of appearance of IgM and IgA antibodies occurred in serum, but IgA antibodies persisted for a shorter period than in fecal or nasal samples. Serum IgG1 antibody responses generally preceeded IgG2 responses and were predominant in most calves after 14-21 DPE.
未哺乳的无特定病原体犊牛在3至4周龄时，通过鼻内（IN）或口服（O）接种牛冠状病毒，或口服加鼻内接种（O/IN），或口服接种牛轮状病毒。使用免疫荧光染色（IF）、酶联免疫吸附测定（ELISA）或免疫电子显微镜（IEM）检测鼻拭子或粪便样本中的病毒脱落情况以及病毒感染的鼻上皮细胞。通过ELISA测定血清、鼻拭子和粪便样本中的同型特异性抗体滴度。接种冠状病毒的犊牛粪便中排出病毒，且在鼻上皮细胞中检测到病毒。鼻内接种的犊牛鼻部分泌病毒的持续时间比口服接种的犊牛更长，且在鼻内接种和口服接种的犊牛中，鼻部分泌病毒的持续时间都比粪便排毒时间长。所有犊牛均出现腹泻，但无呼吸道疾病迹象。接种轮状病毒的犊牛腹泻和粪便排毒模式相似，但通常持续时间比接种冠状病毒的犊牛短。未检测到轮状病毒的鼻部分泌。在大多数犊牛中，暴露后7至10天（DPE）在粪便和鼻拭子样本中检测到IgM抗体反应峰值，随后在10至14 DPE出现IgA抗体反应峰值。即使在接种轮状病毒的犊牛中没有鼻部分泌病毒的情况下，所有接种病毒的犊牛都出现了鼻抗体反应。接种冠状病毒的犊牛粪便和鼻拭子样本中的IgM和IgA抗体滴度高于接种轮状病毒的犊牛。在大多数接种的犊牛中，IgM或IgA抗体的最大滴度与粪便或鼻病毒排毒的停止相关。血清中IgM和IgA抗体出现的顺序相似，但IgA抗体持续时间比粪便或鼻拭子样本短。血清IgG1抗体反应通常先于IgG2反应，并且在14至21 DPE后在大多数犊牛中占主导地位。
