Gross and light-microscopic features of ovine pulmonary hydatidosis and verminous pneumonias in Morocco.

Verminous pneumonias appear to be common in sheep in Morocco, therefore, a systematic study was undertaken to classify the pulmonary changes induced by various parasites in Morocco. A total of 613 pairs of lungs with parasitic pneumonias were diagnosed in 1152 young and adult sheep either slaughtered at two abattoirs in Morocco (487 out of 1152 sheep) or received at necropsy services (126 out of 1152 sheep) over a 15-month period. Based on gross and microscopic findings, four types of pulmonary changes were classified. Included were those associated with: 1. The larvae of Taenia echinococcus (Echinococcus granulosus (canine tapeworm); 520 out of 613 lungs (84.8%)); 2. Muellerius capillaris (450 out of 613 lungs (79.9%)); 3. Protostrongylus rufescens (375 out of 613 lungs (61.1%)); and 4. Dictyocaulus filaria (285 out of 613 lungs (46.4%)). Mixed infestations, involving the presence of two, three, or four species of parasites in the same lung, were encountered in 325 out of 613 (53%) lungs studied. Red-to-brownish consolidated areas, confined to the cranial parts of the lung, were observed frequently in some lungs affected with M. capillaris and P. rufescens. In most of the lungs, co-existent emphysematous, atelectatic, and abscessed areas were seen.