The prevalence of concurrent trypanosome and gastrointestinal nematode infections in west African dwarf sheep and goats in Nsukka area of eastern Nigeria.

The prevalence of concurrent nematode-trypanosome infections in traditionally reared West African Dwarf sheep and goats in eastern Nigeria was monitored over a 12-month period during 1987-1988. The most prevalent nematodes were Haemonchus contortus and Trichostrongylus colubriformis, which usually occurred together in all nematode infected animals. Their combined prevalence rates ranged from 90 to 100% throughout the year and they accounted for 66 to 98% of the total monthly worm burdens. Of the 107 animals examined 13.6% were infected with trypanosome species comprising Trypanosoma brucei (50%), Trypanosoma congolense (43%) and Trypanosoma vivax (36%). No clear seasonal pattern was observed in the prevalence of concurrent nematode-trypanosome infection but owing to the widespread prevalence of gastrointestinal nematode infections, all trypanosome infected animals were invariably infected with H. contortus and Trichostrongylus colubriformis.