Nardelli Stefano, Bettini Astrid, Capello Katia, Bertoni Giuseppe, Tavella Alexander
Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy (Nardelli, Capello) and Bolzano, South Tyrol, Italy (Bettini, Tavella).
Institute of Virology and Immunology, Vetsuisse University of Bern, Bern, Switzerland (Bertoni).
J Vet Diagn Invest. 2020 Jul;32(4):589-593. doi: 10.1177/1040638720934055. Epub 2020 Jun 18.
Since 2007, the Autonomous Province of Bolzano-South Tyrol (Italy) has carried out a compulsory eradication program against caprine arthritis encephalitis virus (CAEV) in goats. A drastic seroprevalence reduction was achieved during the initial phase (2007-2011); however, a tailing phenomenon has been observed during the latest years, hampering the achievement of the final goal. CAEV belongs to a group of lentiviruses, called small ruminant lentiviruses (SRLVs), which are antigenically related and can infect both goats and sheep. We investigated the possible link between the tailing phenomenon in goats and the role of sheep as a virus reservoir by comparing serologic results between multispecies farms (where goats and sheep coexist) and monospecies farms (goats only). Goats on multispecies farms had a higher prevalence and seroconversion rate (even if to a rather moderate extent), higher antibody titers, and a higher probability of conclusive results in the genotyping analysis, with more frequent identification of SRLV genotype A (sheep-related) infections. Sheep can serve as a SRLV reservoir, thus contributing to scattered positive tests in goats, causing the tailing phenomenon.
自2007年以来，意大利博尔扎诺-南蒂罗尔自治区开展了一项针对山羊的山羊关节炎脑炎病毒（CAEV）强制根除计划。在初始阶段（2007 - 2011年）血清阳性率大幅下降；然而，近年来出现了拖尾现象，阻碍了最终目标的实现。CAEV属于一组慢病毒，称为小反刍兽慢病毒（SRLV），它们在抗原上相关，可感染山羊和绵羊。我们通过比较多物种农场（山羊和绵羊共存）和单物种农场（仅山羊）的血清学结果，研究了山羊中的拖尾现象与绵羊作为病毒储存宿主的作用之间的可能联系。多物种农场中的山羊患病率和血清转化率更高（即使程度相当适中）、抗体滴度更高，并且在基因分型分析中得出确定性结果的概率更高，更频繁地鉴定出SRLV基因型A（与绵羊相关）感染。绵羊可作为SRLV的储存宿主，从而导致山羊中出现零散的阳性检测结果，造成拖尾现象。
