Literák Ivan, Smíd Bediich, Dubská Lenka, Bryndza Lukás, Valícek Lubomír
Department of Biology and Wildlife Diseases, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences, Palackého 1-3, 612 42 Brno, Czech Republic.
Avian Dis. 2006 Mar;50(1):120-3. doi: 10.1637/7395-061605R.1.
In winter 2003-04, large numbers of budgerigars (Mellopsitacus undulatus) and cockatiels (Nymphicus hollandicus) fell ill and died in a large parrot-breeding aviary in Slovakia. In budgerigars, the disease outbreak occurred at the age of 2-3 weeks; cockatiels died within their first 7 days of life. In budgerigars, symptoms of the disease included delayed growth, tremor, darkish discoloration of skin, quill bleeding, and feathering defects. cockatiels often died without any symptoms and with a full crop; feathering defects occurred sporadically. Electron microscopy with negative staining of aqueous lysates of the affected skin and of bleeding quills showed isolated or clustered polyomavirus particles 45-50 nm in size. Long filamentous forms of the virus were also found in virion clusters of skin lysates from the budgerigars. In ultrathin sections through the pathologically altered skin tissue of budgerigars, virus particles were present in both nuclei and cytoplasm of epidermal cells, often in crystalline form. In infected cells, enlarged nuclei showed an extensive chromatin margination. On the DNA level, presence of a polyomavirus infection was conclusively proved by the polymerase chain reaction using avian polyomavirus (APV)-specific primers. A sequence analysis of the gene encoding viral protein (VP)1 and of the combined region for VP2 and VP3 proteins revealed a previously undescribed synonymous mutation in this isolate. This report extended the knowledge of the area of APV occurrence and of the spectrum of hosts in the context of genomic and morphologic variability of APV isolates.
2003 - 2004年冬季，斯洛伐克一家大型鹦鹉养殖鸟舍中有大量虎皮鹦鹉（虎皮鹦鹉属）和鸡尾鹦鹉（玄凤鹦鹉属）生病并死亡。虎皮鹦鹉的疾病暴发发生在2 - 3周龄时；鸡尾鹦鹉在出生后的头7天内死亡。虎皮鹦鹉的疾病症状包括生长迟缓、震颤、皮肤颜色变深、羽管出血和羽毛发育缺陷。鸡尾鹦鹉常常没有任何症状且嗉囊饱满就死亡；羽毛发育缺陷偶尔出现。对受影响皮肤和出血羽管的水性裂解物进行负染色的电子显微镜检查显示，有大小为45 - 50纳米的孤立或聚集的多瘤病毒颗粒。在虎皮鹦鹉皮肤裂解物的病毒粒子簇中也发现了病毒的长丝状形式。在虎皮鹦鹉病理改变的皮肤组织超薄切片中，病毒粒子存在于表皮细胞的细胞核和细胞质中，常呈结晶形式。在受感染的细胞中，肿大的细胞核显示出广泛的染色质边缘化。在DNA水平上，使用禽多瘤病毒（APV）特异性引物的聚合酶链反应确凿地证明了多瘤病毒感染的存在。对编码病毒蛋白（VP）1的基因以及VP2和VP3蛋白的组合区域进行的序列分析揭示了该分离株中一个以前未描述的同义突变。本报告扩展了在APV分离株基因组和形态变异背景下对APV发生区域和宿主谱的认识。
