Laboratorio de Virología Molecular, CENUR Litoral Norte, Centro Universitario de Salto, Universidad de la República, Rivera 1350, 50000, Salto, Uruguay.
Instituto Nacional de Investigación Agropecuaria (INIA), Plataforma de Investigación en Salud Animal, Ruta 50 km 11, La Estanzuela, 70000, Colonia, Uruguay.
Arch Virol. 2019 Nov;164(11):2715-2724. doi: 10.1007/s00705-019-04384-w. Epub 2019 Aug 27.
Bovine coronavirus (BCoV) is a recognized cause of severe neonatal calf diarrhea, with a negative impact on animal welfare, leading to economic losses to the livestock industry. Cattle production is one of the most important economic sectors in Uruguay. The aim of this study was to determine the frequency of BCoV infections and their genetic diversity in Uruguayan calves and to describe the evolutionary history of the virus in South America. The overall detection rate of BCoV in Uruguay was 7.8% (64/824): 7.7% (60/782) in dairy cattle and 9.5% (4/42) in beef cattle. The detection rate of BCoV in samples from deceased and live calves was 10.0% (6/60) and 7.6% (58/763), respectively. Interestingly, there was a lower frequency of BCoV detection in calves born to vaccinated dams (3.3%, 8/240) than in calves born to unvaccinated dams (12.2%, 32/263) (OR: 4.02, 95%CI: 1.81-8.90; p = 0.00026). The frequency of BCoV detection was higher in colder months (11.8%, 44/373) than in warmer months (1.5%, 3/206) (OR: 9.05, 95%CI: 2.77-29.53, p = 0.000013). Uruguayan strains grouped together in two different lineages: one with Argentinean strains and the other with Brazilian strains. Both BCoV lineages were estimated to have entered Uruguay in 2013: one of them from Brazil (95%HPD interval: 2011-2014) and the other from Argentina (95%HPD interval: 2010-2014). The lineages differed by four amino acid changes, and both were divergent from the Mebus reference strain. Surveillance should be maintained to detect possible emerging strains that can clearly diverge at the antigenic level from vaccine strains.
牛冠状病毒（BCoV）是一种公认的引起严重新生犊牛腹泻的病原体，对动物福利产生负面影响，导致畜牧业经济损失。牛的养殖是乌拉圭最重要的经济部门之一。本研究的目的是确定 BCoV 在乌拉圭犊牛中的感染频率及其遗传多样性，并描述该病毒在南美洲的进化史。在乌拉圭，BCoV 的总检出率为 7.8%（64/824）：奶牛中为 7.7%（60/782），肉牛中为 9.5%（4/42）。在死亡和存活犊牛的样本中，BCoV 的检出率分别为 10.0%（6/60）和 7.6%（58/763）。有趣的是，来自接种疫苗的母畜的犊牛中 BCoV 的检出率较低（3.3%，8/240），而来自未接种疫苗的母畜的犊牛中 BCoV 的检出率较高（12.2%，32/263）（OR：4.02，95%CI：1.81-8.90；p=0.00026）。BCoV 的检出率在较冷的月份（11.8%，44/373）高于较暖的月份（1.5%，3/206）（OR：9.05，95%CI：2.77-29.53，p=0.000013）。乌拉圭株分为两个不同的谱系：一个与阿根廷株，另一个与巴西株。两个 BCoV 谱系均估计于 2013 年进入乌拉圭：一个来自巴西（95%HPD 间隔：2011-2014），另一个来自阿根廷（95%HPD 间隔：2010-2014）。这两个谱系有 4 个氨基酸的差异，而且都与 Mebus 参考株不同。应进行监测，以发现可能在抗原水平上明显与疫苗株不同的新兴菌株。
