The use of Lespedeza cuneata for natural control of gastrointestinal nematodes in Merino sheep

Lespedeza cuneata (poorman’s lucerne; sericea lespedeza), a tannin-rich perennial legume, was offered as hay to dry Merino ewes in a confined feeding experiment to evaluate the effect on the level of gastrointestinal parasite infection in sheep. Medicago sativa (a low tannin containing perennial legume) was used as the control treatment. Parameters faecal egg count (FEC), FAMACHA(©) scores and rectal temperatures were used. FECs were substantially lower (p = 0.05) in the Lespedeza group after 35 days, together with a trend of higher rectal temperatures, compared with the Medicago group. Although non-significant (p > 0.05), the higher rectal temperatures suggested a lower level of anaemia in the sheep on the Lespedeza ration and, therefore, a lower parasite-worm burden. However, FAMACHA(©) scores showed no significant (p > 0.05) differences between treatments despite the differences in FEC that were recorded, indicating that host homeostasis was possibly mediated by improved nutrition as a result of the high protein content of both experimental diets.