FECAL EGG COUNTS ARE REPRESENTATIVE OF DIGESTIVE-TRACT STRONGYLE WORMBURDENS IN SHEEP AND GOATS

The relationship between faecal egg counts and worm burdens in sheep a nd goats was studied in a large array of environments, from temperate (ewes, lambs or dairy-goats in France) or steppic (ewes in Middle-Alia s of Morocco) to Sahelian (young sheep and goats of Mauritania in West Africa) climates. The studied temperate worm communities were dominat ed by Teladorsagia and Trichostrongylus sp, and those from steppic are as by Teladorsagia, Marshallagia and Trichostrongylus sp,; Haemonchus contortus was highly predominant in the Sahelian regions. The fertilit y of worms depended on density (10 to 50% of variance) and presence of H. contortus to a lesser extent. For sheep and goats from several tem perate and steppic areas, a good relationship between egg counts and w orm burdens was established (r=0.62). it was ameliorated when the perc entage of H. contortus, the most prolific species was incorporated in the model. The predictive value of faecal egg count for assessing worm burden was only of interest for groups of hosts.