Incidence of liver fluke infections (Fasciola gigantica and Dicrocoelium hospes) in ruminants in northern Nigeria.

One thousand and twenty-four cattle, 550 sheep and 1,748 goats slaughtered in a rural slaughter slab during 1973 to 1975 were examined for evidence of liverfluke infections. The prevalence rate of Fasciola gigantica and Dicrocoelium hospes infections was respectively 65.4% and 56.0% in cattle, 40.8 and 13.1% in sheep and 17.6 and 5.2% in goats. Other trematodes detected were Schistosoma bovis and paramphistomes. The seasonal incidence of F. gigantica as well as of D. hospes was highest during and directly after the rainy season. The lower prevalence rate of F. gigantica, especially in the younger animals, during 1973-1974 was thought to be related to the 1973 drought. This was supported by the low prevalence rate in the long-range trade cattle which originated from drier areas. The results are discussed in relation to the climatic conditions during the survey period, as well as to the difference in epidemiology of F. gigantica and D. hospes infections in northern Nigeria.