The occurrence of Onchocerca gutturosa Neumann in cattle in England, with an account of its life history and development in Simulium ornatum Mg

Abstract

1. Onchocerca is recorded for the first time from English-bred cattle.2. A specific diagnosis of O. gutturosa is made, O. bovis being regarded as a synonym. It is suggested that Stiles's description of Filaria lienalis may have referred to this species.3. The microfilariae occur in the skin of infected cows, and blood-sucking flies of the genus Simulium were found to be the vectors.4. Complete development was observed in S. ornatum and partial development in S. erythrocephalum. S. ornatum appears to be a very efficient intermediate host, as over 40 per cent became infected.5. Culicoides nubeculosus, the vector of Onchocerca cervicalis of horses, does not appear to carry the bovine Onchocerca.