Estudo das alterações anátomo-histopatológicas causadas pela infecção experimental por Strongyloides papillossus (WEDL, 1856) Ransom, 1911 em bezerros

Abstract

A study of was perfomed to evoluate the pathological changes in 12 newborn crossbred calves. They were inoculated with 300.000 infective larvae of Strongyloides papillosus (Wedl, 1856) Ranson, 1911. The eggs appeared in the faeces by using the McMaster techinique, around 11th days post inoculation (DPI). Out of the 12 calves, 6 of them died as a result of the infestation and other were sloughtered within 30 to 42 DPI. At the necropsy table, thickning of the visceral pleura, areas of emphysema, atelectasis, and petechial throughout of the lungs were observed. Mesenteric and subcapsular lymph nodes were enlarged. In the initial portion of the small intestine, the mucosa was edemaciated, hyperhemic, and large amount of mucus was observed in lumen. In this area, petechiae ware prominent in the mucosa of duodenum and jejunum. The histopathological examination of the lungs, xvi. besides conformation of lesions observed macroscopically, bronchi and branchiale stenosis, areas of fibrose with lymphohistiocytis infiltrates were noted. Mediastinic and subcapsular lymph nodes had folicular hiperplasia. On the intestine, specifically in the duodenum and the jejunum, the lesions, which was present in all of the calves, were consisted of edema of the mucosa and submucosa, erosion of the mucosa, presenceofmucus and severe lympho-histiocytic and eosinophylic infiltrataes, inthe submucosabesides constant presence of the parasite, either in, between the vilosities or penetrating deeply in the mucosa.