一个关闭的研究集群中的四只斑胸草雀出现了不同的临床症状，包括肿块、皮肤损伤、发抖和/或羽毛蓬乱。这些鸟对治疗措施没有反应；3只死亡，1只被安乐死。所有四只鸟都被送去尸检以确定临床症状的原因。所有鸟类的尸检和组织病理学结果显示多个器官中的圆细胞肿瘤，包括皮肤、肝脏、肾脏和生殖道，并且肿瘤细胞内有核内包涵体。在所有四例中，免疫组织化学染色显示70％至80％的肿瘤圆细胞强烈表达CD3，而较小的一部分阳性细胞表达Pax5。这些结果支持了T细胞淋巴瘤的诊断。从一个病例的冷冻肝组织中经过下一代测序（NGS）发现病毒RNA与最初在欧洲金翅雀中发现的34639株鸟類多瘤病毒序列完全相同。从另一个病例的甲醛固定石蜡埋片中也经过NGS检测，显示病毒RNA与最初在鸟類中发现的37273株鸟類多瘤病毒序列有97.2%的序列同源性。为了定位体内病毒，使用设计用来靶向测序病毒VP1基因的探针，对冷冻肝组织进行了RNAscope杂交检测。在所有四个案例中，检测到了广泛和强烈的杂交信号，表明病毒在肿瘤细胞中播散。这些发现表明鸟類多瘤病毒有致癌的潜力，在斑胸草雀中也是如此。

Four zebra finches in a closed research colony presented with variable clinical signs, including masses, skin lesions,shivering, and/or ruffled feathers. These birds were not responsive to treatment efforts; 3 died and one was euthanized. All4 were submitted for necropsy to determine the cause of the clinical signs. Gross necropsy and histopathologic findings fromall birds resulted in a diagnosis of round cell neoplasia in multiple organs, including the skin, liver, kidney, and reproductivetract, with intranuclear inclusion bodies in the neoplastic cells. In all 4 cases, immunohistochemical staining showed strongimmunoreactivity for CD3 in 70% to 80% of the neoplastic round cells, with a relatively small subset that were immunopositivefor Pax5. These findings supported a diagnosis of T-cell lymphoma. Frozen liver tissue from one case was submittedfor next-generation sequencing (NGS), which revealed viral RNA with 100% sequence homology to canary polyomavirusstrain 34639 that had originally been identified in a European goldfinch. Formalin-fixed paraffin-embedded scrolls fromanother case were also submitted for NGS, which revealed viral RNA with 97.2% sequence homology to canary polyomavirusstrain 37273 that had originally been identified in a canary. To localize the virus in situ, RNAscope hybridizationwas performed using a probe designed to target the VP1 gene of the sequenced virus in frozen liver tissue. In all 4 cases,disseminated and robust hybridization signals were detected in neoplastic cells. These findings indicate that polyomaviruseshave the potential to be oncogenic in zebra finches.