A comparative study of gastrointestinal nematode egg output in N'Dama, Zebu and N'Dama x Zebu crossbred cattle.

Strongyle faecal egg output was estimated in N'Dama, Zebu and N'Dama x Zebu crossbred (F1) cattle. N'Dama cattle showed a significantly lower prevalence of strongyle infection, as measured by faecal egg output, than F1 (P < 0.01) and Zebu (P < 0.001) cattle. In strongyle-infected animals, mean egg output was also significantly lower in N'Damas (P < 0.03) than in Zebus. A previous trypanosomiasis infection did not affect the results. The presence of a natural resistance trait to strongyle infection in N'Dama cattle is postulated.