Canine metacestodes in an organized sheep farm

Abstract

Infections with the larval stages of canine tapeworms were recorded in sheep belonging to an organized sheep farm. Asymptomatic presence of Cysticercus tenuicollis, metacestode of Taenia hydatigena, in the peritoneal cavities of sheep, was encountered during necropsy. Deaths in lambs due to peracute and subacute hepatitis cysticercosa were recorded. The fact that C. tenuicollis lacks the characteristic armed rostellum during the early stages should be taken into account during diagnosis of peracute cysticercosis. During the lean months of winter, overwhelming chronic infection with 53 cysts of C. tenuicollis resulted in death of a hogget. Non-viable, calcified cysts, apparently those of C. ovis (intermediate stage of T. ovis), were documented in the heart muscles of four ewes. Death following cerebral signs of a ewe was attributed to the presence of a single Coenurus cerebralis cyst (larval stage of T. multiceps) in the occipital region of the cranial cavity. The presence of Coenurus acquires public health importance owing to its zoonotic potential. Hydatid cysts were not recorded in any of the sheep. The study shows the importance of restricting access of canids in sheep farms and pastures. Removal of fecal pats of domestic dogs from areas grazed by lambs will prevent fatal cysticercosis caused due to ingestion of gravid proglottids.