Unterweger Christine, Kreutzmann Heinrich, Buenger Moritz, Klingler Eva, Auer Angelika, Rümenapf Till, Truyen Uwe, Ladinig Andrea
University Clinic for Swine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, 1210 Vienna, Austria.
Vetpraxis Hegerberg, 3053 Laaben, Austria.
Vet Sci. 2023 Aug 1;10(8):494. doi: 10.3390/vetsci10080494.
Diverse origins and causes are described for papyraceous mummifications of porcine foetuses, but the porcine reproductive and respiratory syndrome virus (PRRSV) is not one of them. In contrast, PRRSV is unlikely to cause mid-term placental transmission but may cause late-term abortions and weakness of piglets. This case report describes a sudden occurrence of mummified foetuses of various sizes and stillborns and delayed birth (>115 days) in more than 50% of sows from one farrowing batch, while newborn piglets were mostly vital. Neither increased embryonic death nor infertility was reported. Three litters with mummies, autolysed piglets and stillborn piglets were investigated, and infections with porcine parvoviruses, porcine teschoviruses, porcine circoviruses, encephalomyocarditis virus, spp. and spp. were excluded. Instead, high viral loads of PRRSV were detected in the thymus pools of piglets at all developmental stages, even in piglets with a crown-rump length between 80 and 150 mm, suggesting a potential mid-term in utero transmission of the virus. Genomic regions encoding structural proteins (ORF2-7) of the virus were sequenced and identified the virulent PRRSV-1 strain AUT15-33 as the closest relative. This case report confirms the diversity of PRRSV and its potential involvement in foetal death in mid-gestation.
已描述了猪胎儿纸样木乃伊化的多种起源和原因，但猪繁殖与呼吸综合征病毒（PRRSV）不在其中。相比之下，PRRSV不太可能导致中期胎盘传播，但可能导致晚期流产和仔猪虚弱。本病例报告描述了一窝分娩母猪中50%以上突然出现各种大小的木乃伊化胎儿、死产胎儿以及延迟分娩（>115天），而新生仔猪大多存活。未报告胚胎死亡率增加或不育情况。对三窝有木乃伊化胎儿、自溶仔猪和死产仔猪的猪进行了调查，排除了猪细小病毒、猪捷申病毒、猪圆环病毒、脑心肌炎病毒、 spp.和 spp.的感染。相反，在所有发育阶段的仔猪胸腺样本中均检测到高病毒载量的PRRSV，甚至在头臀长为80至150毫米的仔猪中也检测到，这表明该病毒可能在子宫内中期传播。对该病毒编码结构蛋白（ORF2 - 7）的基因组区域进行测序，并确定强毒株PRRSV - 1 AUT15 - 33为最相近毒株。本病例报告证实了PRRSV的多样性及其在妊娠中期胎儿死亡中的潜在作用。
