Abstract Introduction Coinfection of goose parvovirus (GPV) and duck circovirus (DuCV) occurs commonly in field cases of short beak and dwarfism syndrome (SBDS). However, whether there is synergism between the two viruses in replication and pathogenicity remains undetermined. Material and Methods We established a coinfection model of GPV and DuCV in Cherry Valley ducks. Tissue samples were examined histopathologically. The viral loads in tissues were detected by qPCR, and the distribution of the virus in tissues was detected by immunohistochemistry (IHC). Results Coinfection of GPV and DuCV significantly inhibited growth and development of ducks, and caused atrophy and pallor of the immune organs and necrosis of the liver. GPV and DuCV synergistically amplified pathogenicity in coinfected ducks. In the early stage of infection, viral loads of both pathogens in coinfected ducks were significantly lower than those in monoinfected ducks (P < 0.05). With the development of the infection process, GPV and DuCV loads in coinfected ducks were significantly higher than those in monoinfected ducks (P < 0.05). Extended viral distribution in the liver, kidney, duodenum, spleen, and bursa of Fabricius was consistent with the viral load increases in GPV and DuCV coinfected ducks. Conclusion These results indicate that GPV and DuCV synergistically potentiate their replication and pathogenicity in coinfected ducks.

中文翻译：

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鹅细小病毒和鸭圆环病毒共感染鸭对鸭的影响

摘要 简介 鹅细小病毒（GPV）和鸭圆环病毒（DuCV）共感染常见于野外短喙侏儒症综合征（SBDS）病例。然而，这两种病毒在复制和致病性方面是否存在协同作用仍有待确定。材料与方法 我们建立了樱桃谷鸭中GPV和DuCV的共感染模型。组织病理学检查组织样品。通过qPCR检测组织中的病毒载量，通过免疫组织化学（IHC）检测病毒在组织中的分布。结果GPV与DuCV共感染显着抑制鸭的生长发育，并引起免疫器官萎缩、苍白和肝脏坏死。GPV 和 DuCV 在共感染鸭中协同放大致病性。在感染初期，双重感染鸭中两种病原体的病毒载量均显着低于单一感染鸭（P < 0.05）。随着感染过程的发展，共感染鸭的GPV和DuCV载量显着高于单感染鸭（P < 0.05）。病毒在肝、肾、十二指肠、脾和法氏囊中的扩展分布与 GPV 和 DuCV 共感染鸭的病毒载量增加一致。结论 这些结果表明 GPV 和 DuCV 协同增强了它们在共感染鸭中的复制和致病性。病毒在肝、肾、十二指肠、脾和法氏囊中的扩展分布与 GPV 和 DuCV 共感染鸭的病毒载量增加一致。结论 这些结果表明 GPV 和 DuCV 协同增强了它们在共感染鸭中的复制和致病性。病毒在肝、肾、十二指肠、脾和法氏囊中的扩展分布与 GPV 和 DuCV 共感染鸭的病毒载量增加一致。结论 这些结果表明 GPV 和 DuCV 协同增强了它们在共感染鸭中的复制和致病性。