Veterinary Pathology Division, Faculty of Veterinary Medicine, Teramo University, Italy.
Vet Pathol. 2011 Sep;48(5):975-84. doi: 10.1177/0300985810391112. Epub 2010 Dec 15.
West Nile virus (WNV) infection was diagnosed in 38 psittacine birds based on histology, immunohistochemistry, and reverse transcriptase polymerase chain reaction (RT-PCR). Rosellas (Platycercus spp, n = 13), conures (Enicognathus, Aratinga, and Nandayus spp, n = 6), and lorikeets (Trichoglossus spp, n = 6) represented the most commonly affected species. Clinical signs ranged from lethargy, ruffled feathers, anorexia, and weight loss in most birds to sudden death in others. Except for mild to moderate enlargement of liver and spleen, there were no significant gross lesions at necropsy. Histopathologic findings included lymphoplasmacytic and histiocytic hepatitis, interstitial nephritis, myocarditis, splenitis, enteritis, pancreatitis, and occasionally, encephalitis. Viral antigen was detected by immunohistochemistry in 34 of 35 hearts (97.1%), 29 of 32 pancreata (90.6%), 33 of 37 kidneys (89.2%), 31 of 35 intestines (88.6%), 27 of 33 gizzards (81.8%), 8 of 10 ovaries (80%), 27 of 34 spleens (79.4%), 30 of 38 livers (78.9%), 23 of 32 lungs (71.9%), 21 of 31 proventriculi (67.7%), 14 of 21 adrenals (66.7%), 10 of 16 testes (62.5%), 17 of 30 brains (56.7%), 15 of 27 skins (55.5%), 3 of 6 oviducts (50%), 15 of 34 skeletal muscles (44.1%), 11 of 27 crop or esophagus (40.7%), and 1 of 6 thymuses (16.7%). Kidney was positive for WNV by RT-PCR in all the cases tested. In conclusion, Psittaciformes are susceptible to West Nile virus infection, and WNV infections are often associated with nonspecific clinical signs and widespread viral distribution in this order of birds.
根据组织病理学、免疫组织化学和逆转录聚合酶链反应 (RT-PCR)，38 只鹦鹉类鸟类被诊断出感染西尼罗河病毒 (WNV)。凤头鹦鹉 (Platycercus spp，n = 13)、金刚鹦鹉 (Enicognathus、Aratinga 和 Nandayus spp，n = 6) 和吸蜜鹦鹉 (Trichoglossus spp，n = 6) 是最常受影响的物种。临床症状从大多数鸟类的昏睡、羽毛蓬乱、食欲不振和体重减轻到其他鸟类的突然死亡不等。除了肝脏和脾脏轻度至中度肿大外，剖检时没有明显的大体病变。组织病理学发现包括淋巴细胞浆细胞和组织细胞性肝炎、间质性肾炎、心肌炎、脾炎、肠炎、胰腺炎，偶尔还有脑炎。免疫组织化学检测到 35 个心脏中的 34 个（97.1%）、32 个胰腺中的 29 个（90.6%）、37 个肾脏中的 33 个（89.2%）、35 个肠道中的 31 个（88.6%）、33 个嗉囊中的 27 个（81.8%）、10 个卵巢中的 8 个（80%）、34 个脾脏中的 27 个（79.4%）、38 个肝脏中的 30 个（78.9%）、32 个肺脏中的 23 个（71.9%）、31 个前胃中的 21 个（67.7%）、21 个肾上腺中的 14 个（66.7%）、16 个睾丸中的 10 个（62.5%）、30 个脑中的 17 个（56.7%）、27 个皮肤中的 15 个（55.5%）、6 个输卵管中的 3 个（50%）、34 个骨骼肌中的 15 个（44.1%）、11 个嗉囊或食道中的 27 个（40.7%）和 6 个胸腺中的 1 个（16.7%）。所有检测的病例中，肾脏通过 RT-PCR 检测到 WNV 呈阳性。总之，凤头鹦鹉类易感染西尼罗河病毒，该病毒感染常与该鸟类目中的非特异性临床症状和广泛的病毒分布有关。
