Start Date: Mar 18, 2008
End Date: Jan 12, 2012
Controlled environment, field plot, and laboratory experiments will be conducted to determine growth habit, herbage yield, and chemical composition of non-traditional pasture legumes, forbs and grasses with potential for use as forage or forage supplements for small ruminants. Emphasis will be placed on plant species having physical properties or chemical constituents that disrupt the life cycle of the gastrointestinal nematode, Haemonchus contortus or provide immune system support for the ruminant. Non-traditional plant species used in these studies include condensed tannin-containing legumes, American potato bean, purslane, artemisia, and chicory. Condensed tannin-containing forage species will be evaluated for economic potential for hay production under central Appalachian growing conditions using criteria of yield, forage quality, and stand persistence. Native Appalachian plant species that have the potential to provide sufficient yield and bioactive constituents for small ruminants will be identified. The effect of plant species, management, and season on antioxidant capacity of traditional and non-traditional forage species will be measured using samples from multi-year field studies. The influence of edaphic and solar conditions on physical and chemical properties of plant resources will be determined using plants grown with and without mineral deficiencies, with varying levels of UV light, or with natural radiation attenuation. Potential adverse effects of non-traditional plant resources on rumen metabolism and potential alterations in bioactivity by rumen microbial activity will be assessed using in vitro rumen fermentation assays. Anthelmintic activity of plant materials and isolated constituents will be determined using in vitro and in vivo parasite assays. The effect of plant morphology, sward density, and canopy height on hatching and migration of parasite larvae will be evaluated to determine how physical characteristics of pastures can be manipulated to disrupt the parasite life cycle.