|Walker, Elizabeth -|
Submitted to: Small Ruminant Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 23, 2010
Publication Date: January 8, 2011
Citation: Mackown, C.T., Brown, M.A., Walker, E.L. 2011. Tannin rich peanut skins lack anthelmintic properties. Small Ruminant Research. 96:195-200. Interpretive Summary: Occurrence of anthelmintic resistance to currently marketed chemotherapies is a challenge to small ruminant producers throughout the world. Small ruminant production systems that rely solely on synthetic drugs to control gastrointestinal nematode (GIN) parasites will require a shift to integrated multiple strategies to be sustainable in the future. Plants rich in condensed tannins (CT) can have beneficial anthelmintic properties. Peanut skins (PS), an agricultural by-product, are a rich source of CT, have low fiber, and high levels of oil and crude protein. To test the anthelmintic properties of PS, feed pellets formulated with PS or alfalfa (control, trace CT level) were fed to lambs with either low or high GIN infections as indicated by fecal egg counts (FEC). Regardless of the initial level of GIN burden, the FEC levels of lambs fed PS pellets were not reduced compared to lambs fed alfalfa pellet. In these trials, intake of peanut skin may have been insufficient to decrease GIN parasite activity, or perhaps the low prodelphinidin subunit composition of CT in peanut skin prevented a beneficial response. These results will be useful to small ruminant scientist and producers seeking alternative GIN therapies.
Technical Abstract: Gastrointestinal nematode (GIN) resistance to synthetic anthelmintics in small ruminants has led to the evaluation of feed sources containing naturally occurring bioactive secondary metabolites that lessen parasite activity. Plants rich in condensed tannins (CT) can have beneficial anthelmintic properties. Peanut (Arachis hypogea L.) skins (testa), an agricultural by-product, are a rich source of CT, have low fiber and high levels of oil and crude protein, and have been incorporated into feed products for the cattle industry. Anthelmintic activity of pellets formulated with peanuts skins were compared to commercial alfalfa (Medicago sativa L.) pellets (control diet) fed to lambs in two separate experiments, one with initially low and the other high burdens of GIN. In both experiments pellets were fed (six lambs per treatment) at 2.3% BW every other day three times a week. Overall, average daily intake of CT as quebracho (Schinopsis sp.) equivalents of peanuts skin pellets formulated with with 5% molasses was 0.38% BW (low GIN lambs), and that of peanut skin pellets formulated with 48% alfalfa and 7% molasses was 0.53% BW (high GIN lambs). Regardless of the initial level of GIN burden and the formulation of the peanut skin pellets, average daily weight gain of all lambs was about 94 ± 7.2 g per day. Increases in fecal egg count and decreases in blood pack cell volumes that occurred during the trials were not significantly different (P > 0.05) between lambs fed the control alfalfa pellets and lambs fed peanut skin containing pellets. In these trials, intake of peanut skin may have been insufficient to decrease GIN parasite activity, or perhaps the low prodelphinidin subunit composition of CT in peanut skin prevented a beneficial response.