Cerebral and non-cerebral coenurosis in small ruminants.

Cerebral coenurosis is caused by Coenurus cerebralis, the larval stage of Taenia multiceps. The metacestode causes severe lesions in the brain and spinal cord of the intermediate host, so-called "gid" or "stagger" disease. Whereas, the non-cerebral coenurosis caused by Coenurus gaigeri, the larval stage of Taenia gaigeri, particularly affects goats. The cyst form of the Taenia gaigeri is found in intramuscular and subcutaneous tissues. The difference in the sequence of mitochondrial genes of cox1 and nadI and also other variations reported for clinical, morphological and pathological aspects in coenurosis lead to the hypothesis that there is genetic intraspecific variability within this species, such as in other members of the genus Taenia. Nevertheless, it has been shown that sheep and goats have been infected by both cerebral and non-cerebral coenurosis and it has been suggested that such cerebral and non-cerebral metacestodes may belong to different species of Taenia which are host specific for these hosts.