Sánchez-Sánchez Roberto, Vázquez-Calvo Ángela, Fernández-Escobar Mercedes, Regidor-Cerrillo Javier, Benavides Julio, Gutiérrez Jorge, Gutiérrez-Expósito Daniel, Crespo-Ramos Francisco José, Ortega-Mora Luis Miguel, Álvarez-García Gema
SALUVET Group, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain.
SALUVET-Innova, S.L., Complutense University of Madrid, 28040 Madrid, Spain.
Pathogens. 2021 Nov 20;10(11):1518. doi: 10.3390/pathogens10111518.
is an apicomplexan parasite that can cause abortions and perinatal mortality in sheep. Although ovine neosporosis has been described worldwide, there is a lack of information about the relationship between serostatus and the reproductive performance. In this study, we described the infection dynamics in a dairy sheep flock with an abortion rate up to 25% and a seroprevalence of 32%. Abortions were recorded in 36% and 9% of seropositive and seronegative sheep, respectively. Seropositive sheep were more likely to abort twice (OR = 4.44) or three or more times (OR = 10.13) than seronegative sheep. Endogenous transplacental transmission was the main route of transmission since 86% of seropositive sheep had seropositive offspring. Within dams that had any abortion, seropositive sheep were more likely than seronegative ones to have female descendants that aborted (OR = 8.12). The slight increase in seropositivity with the age, the low percentage of animals with postnatal seroconversion or with low avidity antibodies, and the seropositivity of one flock dog, indicated that horizontal transmission might have some relevance in this flock. A control programme based on selective culling of seropositive sheep and replacement with seronegative animals was effective in reducing the abortion rate to 7.2%.
是一种顶复门寄生虫，可导致绵羊流产和围产期死亡。尽管绵羊新孢子虫病已在全球范围内得到描述，但关于血清学状态与繁殖性能之间的关系仍缺乏相关信息。在本研究中，我们描述了一个流产率高达25%且血清阳性率为32%的奶羊群体中的感染动态。血清阳性和血清阴性绵羊的流产率分别为36%和9%。血清阳性绵羊比血清阴性绵羊更有可能流产两次（比值比=4.44）或三次及以上（比值比=10.13）。内源性经胎盘传播是主要传播途径，因为86%的血清阳性绵羊产下的后代血清呈阳性。在有过流产的母羊中，血清阳性母羊比血清阴性母羊更有可能产下流产的雌性后代（比值比=8.12）。血清阳性率随年龄略有增加、产后血清转换或低亲和力抗体的动物比例较低以及一只羊群犬的血清阳性，表明水平传播在该群体中可能具有一定相关性。基于选择性淘汰血清阳性绵羊并用血清阴性动物替代的控制方案有效地将流产率降低到了7.2%。
