Pseudocorynosoma constrictum (Van Cleave, 1918) is a polymorphid acanthocephalan that attaches to the digestive tract of waterfowl to complete its life cycle, causing severe histological damage to its definitive avian hosts. In the present study, we present a histopathological analysis of the lesions that P. constrictum induced in the layers of the ileum of the blue-winged teal Anas discors. The results revealed that worms insert the attachment structures into the inner gut muscular layer, which causes substantial swelling, haemorrhaging and necrosis in the tissue near the parasite's proboscis. We also observed that the number of parasites attached to the tissue can obstruct the intestinal lumen; in the most serious case, we observed more than 30 parasites penetrating completely the walls of the bird intestine.

中文翻译：

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蓝翅蠹回肠缩窄假锥虫（棘头蚴科：Polymorphidae）病变的组织病理学

缩窄性假锥虫(Van Cleave, 1918) 是一种多形棘头动物，它附着在水禽的消化道上以完成其生命周期，对其最终的鸟类宿主造成严重的组织学损伤。在本研究中，我们对以下病变进行组织病理学分析：P. constrictum在蓝翅蓝绿色的回肠层中诱导鼻涕虫. 结果表明，蠕虫将附着结构插入肠道内肌层，导致寄生虫长鼻附近组织出现大量肿胀、出血和坏死。我们还观察到附着在组织上的寄生虫数量会阻塞肠腔。在最严重的情况下，我们观察到 30 多种寄生虫完全穿透了鸟肠壁。