鸭源呼肠孤病毒感染引起雏鸭免疫损伤的观察

Observation of Duckling Immune Injury Caused by Duck-Origined Reovirus Infection

【目的】观察鸭源呼肠孤病毒对雏鸭脾、法氏囊的病理损伤及相关免疫指标,初步阐明鸭源呼肠孤病毒对所引起的机体免疫器官损伤以及机体免疫抑制,为进一步探讨发病机理和免疫防治提供理论依据。【方法】7日龄樱桃谷雏鸭人工感染鸭源呼肠孤病毒,分别观察脾、法氏囊组织病理学变化,检测脾、法氏囊指数,外周血CD3+、CD8+T细胞阳性率,脾、法氏囊IgY生成细胞,并分析试验组及对照组差异显著性。【结果】感染鸭源呼肠孤病毒后,雏鸭脾出现明显坏死灶,之后出现肉芽肿结构,法氏囊固有层淋巴滤泡明显减少;脾、法氏囊指数降低;外周血CD3+、CD8+T细胞阳性率降低;脾IgY生成细胞数量增多、法氏囊IgY生成细胞数量减少。【结论】鸭源呼肠孤病毒感染可导致雏鸭免疫器官严重损伤并引起免疫抑制。

【Objective】 The pathological damages of spleen and bursa of Fabricius in ducklings caused by duck-deprived reovirus and related immune index were observed. The mechanisms of immune organ damage and immune suppression upon duck-derived reovirus infection were studied for providing a theoretical basis for further studies on pathogenesis and immune prevention and control. 【Method】 Cherry Valley ducklings at 7-day old of age were artificially infected with duck-derived reovirus, then histopathological changes of spleen and bursa of Fabricius were observed. Spleen and bursa index, the positive rate of CD3＋, CD8＋ T cells in peripheral blood,and IgY-producing cells of spleen and bursa of Fabricius were detected. A significant difference between experimental and control group was analyzed. 【Result】 After the infection of duck-derived reovirus, notable necrosis was found in duckling spleen, followed by granuloma structure, and lymphoid follicles on lamina propia decreased significantly. The spleen and bursa indexes were reduced. The positive rate of CD3＋, CD8＋ T cells in peripheral blood also decreased. IgY -producing cells increased in spleen but decreased in bursa of Fabricius. 【Conclusion】 Duckling-origined reovirus infection may lead to severe injury of the ducklings immune organs and induce mmune suppression.