Masot A Javier, Gil María, Risco David, Jiménez Olga M, Núñez José I, Redondo Eloy
Unidad de Histología y Anatomía Patológica, Departamento de Medicina Animal, Facultad de Veterinaria, Universidad de Extremadura, Avda. Universidad s.n., Cáceres, 10003, Spain.
Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain.
BMC Vet Res. 2017 Jan 5;13(1):6. doi: 10.1186/s12917-016-0938-7.
The only natural hosts of Pseudorabies virus (PRV) are members of the family Suidae (Sus scrofa scrofa). In species other than suids infection is normally fatal. In these mammals, including carnivores, PRV typically causes serious neurologic disease. The endangered Iberian lynx (Lynx pardinus) is a wild feline endemic to south-western Europe (Iberian Peninsula). The Iberian lynx was found to be the world's most endangered felid species in 2002. In wild felines, PRV infection has only been previously reported once in a Florida panther in 1994. No seropositive lynxes have ever been found, nor has PRV been detected in dead Iberian lynxes to date.
We describe the first reported case of pseudorabies in an Iberian lynx (Lynx pardinus). Pseudorabies was diagnosed in a young wild Iberian lynx from Extremadura (SW Spain) by histopathological examination, immunohistochemistry, polymerase chain reaction (PCR) and sequence analysis. Gross lesions included alopecia of the ventral neck, bloody gastro-intestinal contents and congestion of the brain. Histopathological analysis showed a moderate nonsuppurative meningoencephalitis with diffuse areas of demyelination, necrotizing gastritis and enteritis of the small intestine. Pseudorabies virus (PRV) antigen was found in neuronal and non-neuronal cells of the brain, tonsils, and gastric glandular epithelial cells by immunohistochemical analysis. The presence of the virus in the brain was confirmed by nested PCR. The sequence analysis of the 146 bp fragment (from the viral glycoprotein B gene) showed that the amplified sequence matched (with 100% identity) the PRV genome. Furthermore, specific DNA from glycoprotein D and E encoding-genes was detected by conventional and real-time PCR, respectively, confirming the latter that this infection was produced by a wild-type PRV strain.
This study supports the suspicion that PRV could infect the Iberian lynx. The detection of PRV in a dead Iberian lynx suggests that the virus may have a negative impact on the survival of endangered lynxes in the wild. However, because this is the first verified instance of lynx mortality resulting from pseudorabies, its true impact on the population is unknown.
伪狂犬病病毒（PRV）的唯一自然宿主是猪科动物（野猪）。在猪科动物以外的物种中，感染通常是致命的。在这些哺乳动物中，包括食肉动物，PRV通常会引发严重的神经疾病。濒危的伊比利亚猞猁（Lynx pardinus）是一种原产于欧洲西南部（伊比利亚半岛）的野生猫科动物。2002年，伊比利亚猞猁被发现是世界上最濒危的猫科动物。在野生猫科动物中，此前仅在1994年有过一例关于佛罗里达美洲狮感染PRV的报道。迄今为止，尚未发现血清学呈阳性的猞猁，在死亡的伊比利亚猞猁中也未检测到PRV。
我们描述了首例伊比利亚猞猁（Lynx pardinus）伪狂犬病的报道病例。通过组织病理学检查、免疫组织化学、聚合酶链反应（PCR）和序列分析，确诊了一只来自埃斯特雷马杜拉（西班牙西南部）的野生幼年伊比利亚猞猁感染了伪狂犬病。肉眼可见的病变包括颈部腹侧脱毛、胃肠道内有血性内容物以及脑部充血。组织病理学分析显示为中度非化脓性脑膜脑炎，伴有弥漫性脱髓鞘区域、坏死性胃炎和小肠肠炎。通过免疫组织化学分析，在脑、扁桃体和胃腺上皮细胞的神经元和非神经元细胞中发现了伪狂犬病病毒（PRV）抗原。通过巢式PCR证实了病毒在脑中的存在。对146bp片段（来自病毒糖蛋白B基因）的序列分析表明，扩增序列与PRV基因组匹配（100%同源）。此外，分别通过常规PCR和实时PCR检测到了糖蛋白D和E编码基因的特异性DNA，进一步证实该感染是由野生型PRV毒株引起的。
本研究支持了PRV可能感染伊比利亚猞猁的怀疑。在一只死亡的伊比利亚猞猁中检测到PRV表明，该病毒可能对野生濒危猞猁的生存产生负面影响。然而，由于这是首例经证实的猞猁因伪狂犬病死亡的病例，其对种群的真正影响尚不清楚。
