Effects of Grazing Chicory and Chicory-Clover Mixtures On the Parasite Burden of Lambs and Kids.

The overuse and improper use of commercial anthelmintics in ruminant animals has led to the development of resistant parasites.  Anthelmintic resistant nematodes, particularly Haemonchus contortus, are a particular threat to small ruminants.  Studies on condensed tannin (CT) containing forages have shown them to be effective in reducing the populations of certain parasites, including H. contourus, to below economic thresholds.  Chicory (Chichorium intybus ) is one of the forage crops reported to be an effective anthelmintic for use in sheep and goats.  Many wildlife food plot seed mixtures contain chicory and other CT containing forages.  Wildlife food plot forage mixtures contain forage plants of high protein content; some of which can produce forage during the hot summer months when cool season grass production is reduced.  This study looked at the growth and development of weaned Dorset lambs and Boer kids when grazed under four grazing regimes; chicory, chicory and clover mixed forage, tall fescue, and tall fescue plus commercial anthelmintic.  The tall fescue (Festuca arundinacea) paddocks serve as a forage check and the tall fescue with commercial anthelmintic paddocks provides for a anthelmintic effectiveness check.  Two one-acre paddocks were established for each of the four forage treatments; sheep and goats were grazed in separate paddocks to permit researchers to observe species specific grazing habits. Six animals of each species were grazed on each of the four forage treatments for six weeks, with blood and fecal samples taken, body weight data, and FAMACHA score evaluations collected during weeks 0, 2, 4, and 6.  Plant samples were collected at weeks 0, 2, 4, and 6 for forage quality analysis and CT content determination. Following the conclusion of the study, two animals from each treatment and species were humanely harvested and a post mortem examination of their digestive tracts made to identify the species of intestinal nematodes present and count the number of adult worms present in each animal to determine the effectiveness of the forage treatments.