Onchocerca armillata Railliet and Henry, 1909 and Onchocerca gutturosa (Neumann, 1910) in camels (Camelus dromedarius L.) in the Sudan

A study undertaken to determine the Onchocerca species infecting camels that live in the same localities as cattle in the Dinder Region, Blue Nile Province, Sudan revealed concurrent infections with the bovine parasites Onchocerca armillata in the thoracic aorta, brachiocephalic trunks and brachial arteries and Onchocerca gutturosa in the ventral side of the lamellar parts of the ligamentum nuchae. The microfilariae of both species had the same predilection sites in the skin of the ears, head and neck regions. Those of O. gutturosa outnumber those of O. armillata but both are smaller than the respective uterine microfilariae. Males and microfilariae of both species are smaller than those of cattle origin.

Onchocerca armillata: prevalence and pathology in Sudanese cattle

Cattle of various ages from Khartoum Province and western Sudan were surveyed for Onchocerca armillata infection by skin snip examination and some also at post-mortem examination. The former method reliably detected infection in cattle aged between nine months and eight years. Several of the older infected animals had no microfilariae in their skin. Prevalence rate and number of microfilariae per gram of skin were higher in male than in female cattle and in animals from western Sudan than those from Khartoum province. Severe pathological changes were seen in the thoracic aorta, brachiocephalic, costocervical and brachial arteries and posteriorly in the abdominal aorta to its bifurcation into the iliac arteries.