Veterinary Population Medicine Department, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN, 55108, USA; Department of Veterinary Pathology, College of Veterinary Science and Animal Husbandry, Pandit Deen Dayal Upadhyaya Veterinary Science University and Cattle Research Institute, Mathura, U.P, 281001, India.
Department of Veterinary and Biomedical Sciences, Animal Disease Research and Diagnostic Laboratory, South Dakota State University, Brookings, SD, 57007, USA; Department of Pathology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Sharkia, 44511, Egypt.
Microb Pathog. 2022 Dec;173(Pt A):105790. doi: 10.1016/j.micpath.2022.105790. Epub 2022 Sep 25.
Turkey arthritis reovirus (TARV) has been established as a cause of lameness in meat type turkeys in the past decade. However, no information is available on the age susceptibility of TARV or its transmission dynamics. We conducted this study to determine the age at which turkey poults are susceptible to TARV infection and whether infected birds can horizontally transmit the virus to their non-infected pen mates (sentinels). Five groups of turkeys were orally inoculated with TARV (∼10 TCID/ml) at 2, 7, 14, 21 and 28 days of age (DOA). Two days after each challenge, four uninfected sentinel turkeys of equal age were added to the virus-inoculated groups. At one- and two-weeks post infection, turkeys from each group, including two sentinels, were euthanized followed by necropsy. Inoculated birds in all age groups had TARV replication in the intestine and gastrocnemius tendon with no statistically significant variation at p < 0.5. Furthermore, the inoculated birds at different age groups showed consistently high gastrocnemius tendon histologic lesion scores while birds in the 28-days-old age group had numerically lower lesion scores at 14 days post inoculation (dpi). The sentinels, in turn, also showed virus replication in their intestines and tendons and histologic lesions in gastrocnemius tendons. The findings indicate that turkeys at the age of 28 days or less are susceptible to infection with TARV following oral challenge. It was also found that TARV-infected birds could transmit the infection to naïve sentinel turkeys of the same age.
过去十年，火鸡关节炎呼肠孤病毒（TARV）已被确定为肉用火鸡跛行的病因。然而，目前尚无关于 TARV 的年龄易感性或其传播动力学的信息。我们进行了这项研究，以确定火鸡雏鸡感染 TARV 的年龄以及感染的鸟类是否可以将病毒水平传播给它们未感染的同笼同伴（哨兵）。将五组火鸡在 2、7、14、21 和 28 日龄（DOA）时经口接种 TARV（约 10 TCID/ml）。每次挑战后两天，将四只年龄相等的未感染哨兵火鸡添加到病毒接种组中。感染后 1 周和 2 周，从每组包括两只哨兵在内的火鸡进行安乐死并进行剖检。在所有年龄组中，接种的鸟类在肠道和腓肠肌腱中均有 TARV 复制，在 p<0.5 时没有统计学上的显著差异。此外，不同年龄组的接种鸟类始终显示出高腓肠肌腱组织学病变评分，而 28 日龄组的鸟类在接种后 14 天的病变评分则较低。反过来，哨兵鸟类也在其肠道和肌腱中显示出病毒复制以及腓肠肌腱的组织学病变。这些发现表明，在口服挑战后，28 日龄或以下的火鸡容易感染 TARV。还发现，感染 TARV 的鸟类可以将感染传播给同年龄的未感染哨兵火鸡。
