Histopathological survey of Sarcocystiosis in slaughtered animal tissues in Benue State, Nigeria

Abstract

Sarcocystosis is an important and common disease of domestic animals, yet not much is known about it in Benue State. This research was conducted with the aim to survey the rate of contamination of slaughtered ruminants and pigs with Sarcocystis species using histopathological method during the wet season. The study comprised of 1200 carcasses examined macroscopically, subsequently, tissue samples from skeletal muscle, heart, esophagus, tongue and diaphragm were considered for pathologic studies using the Hematoxylin and Eosin staining technique. The results showed that the highest rate of infection were observed in skeletal muscles of pigs in Makurdi (33.6 %). Infection was associated with joint raising of both cattle and pigs (P < 0.05) but no significant difference was observed between sex (P>0.05) and two different age groups of animals (P>0.05). Macrocysts of white color, oval shape and size range of approximately 2-5 mm were observed in 12 different skeletal muscles of studied pigs, five of which contained microcysts and macrocysts. Observation of cysts of elongated/fusiform and oval shape of different size suggest the presence of at least two species. To the best of our knowledge, these results represent the first demonstration of these parasites in farm animals of Benue State. The results show that Sarcocystis infection is widely distributed in animals slaughtered for meat. The close proximity between livestock and humans on farms, and the frequently poor sanitary conditions in human dwellings strongly suggest an effective life cycle of the parasite. Further molecular analysis is required to allow for species identification and implementation of adequate strategies for the control of zoonotic infection in Nigeria.