Stipp Danilo T, Barry Aline F, Alfieri Alice F, Takiuchi Elisabete, Amude Alexandre M, Alfieri Amauri A
Laboratory of Animal Virology, Department of Preventive Veterinary Medicine, Universidade Estadual de Londrina. Campus Universitário, PO Box 6001, 86051-990, Londrina, Paraná, Brazil.
Trop Anim Health Prod. 2009 Oct;41(7):1563-7. doi: 10.1007/s11250-009-9347-2. Epub 2009 Apr 16.
Bovine coronavirus (BCoV) is one of the main causes of neonatal calf diarrhoea. Several diagnostic assays have been employed to detect the presence of the virus in stool samples from calves. Despite this, the frequency of BCoV infection among Brazilian and even South American cattle herds has yet to be well characterised. This study describes the occurrence of BCoV infection among calves from dairy and beef herds in four Brazilian states. A total of 282 stool samples from 1 to 60-day-old calves were evaluated for the presence of BCoV by a semi-nested (SN) PCR assay. The animals were from herds (n = 23) located in three geographical regions in Brazil (south, southeast, and center-west). The specific BCoV amplicon was detected in 15.6% (44/282) of the faecal specimens examined, of which 95.4% (42/44) were from diarrhoeic and 4.6% (2/44) from asymptomatic calves. The specificity of the SN-PCR amplicons was evaluated by restriction fragment length polymorphism (RFLP) analysis. The results show that the BCoV is widespread, mainly among calves from 16 to 30-days-old (p = 0.0023), and verify the association between BCoV infection and clinical signs of diarrhoea (p = 0.005). These findings emphasise the importance of this virus in enteric infections of Brazilian cattle herds.
牛冠状病毒（BCoV）是新生犊牛腹泻的主要病因之一。已经采用了几种诊断检测方法来检测犊牛粪便样本中该病毒的存在。尽管如此，巴西乃至南美牛群中BCoV感染的频率尚未得到很好的描述。本研究描述了巴西四个州奶牛和肉牛群中犊牛BCoV感染的发生情况。通过半巢式（SN）PCR检测法对来自1至60日龄犊牛的总共282份粪便样本进行了BCoV检测。这些动物来自位于巴西三个地理区域（南部、东南部和中西部）的牛群（n = 23）。在所检测的粪便标本中，15.6%（44/282）检测到了特异性的BCoV扩增子，其中95.4%（42/44）来自腹泻犊牛，4.6%（2/44）来自无症状犊牛。通过限制性片段长度多态性（RFLP）分析评估了SN-PCR扩增子的特异性。结果表明，BCoV广泛存在，主要在16至30日龄的犊牛中（p = 0.0023），并证实了BCoV感染与腹泻临床症状之间的关联（p = 0.005）。这些发现强调了这种病毒在巴西牛群肠道感染中的重要性。
