|Turner, Kenneth - Ken|
Submitted to: Proceedings of the Annual Appalachian Opportunities Symposium
Publication Type: Proceedings
Publication Acceptance Date: 7/17/2009
Publication Date: 7/27/2009
Citation: Foster, J.G., Cassida, K.A., Turner, K.E., Sanderson, M.A., Shulaw, W.P., Mccutcheon, J.S., Cooper, T.A., Parish, J.R., Rosskopf, E.N. 2009. Plant Constituents: Opportunities to Control Haemonchus contortus. In: Morales, M., editor. Proceedings of the Appalachian Small Ruminant Grazing Workshop. Improving Small Ruminant Grazing Practices, July 11, 2009, Beaver, WV. p. 33-45. Interpretive Summary:
Technical Abstract: The rapidly diminishing effectiveness of commercial dewormers against Haemonchus contortus (barberpole worm) is a serious threat to the sheep and goat industries. In the absence of new anthelmintic drugs, phytochemicals are considered the most promising supplemental approaches for control of this economically important gastrointestinal parasite. Condensed tannins in herbaceous forages and sesquiterpene lactones from forage chicory have exhibited anthelmintic activities. Use of tanniferous legumes for parasite control in temperate climates is the target of numerous investigations, but achievement of this objective is complicated by establishment problems. On the other hand, chicory is relatively easy to establish in temperate environments. Quantitative analyses of the sesquiterpene lactones in chicory herbage and in vitro parasitology assays suggest that cultivars with a high sesquiterpene lactone concentration and a sesquiterpene lactone composition dominated by 8-deoxylactucin may be the best choices for bioactive pastures for H. contortus control. In vitro and controlled-environment studies with emulsions of oils extracted from orange peels suggest that orange terpenes might be used successfully to disrupt the life cycle of H. contortus. They provide the foundation for field and animal studies that are necessary before on-farm use of orange oils for H. contortus control can be considered.