Agrotechnological aspects of the anti-malarial plant Artemisia annua and its potential use in animal health in Appalachia

Haemonchus contortus is the most detrimental gastrointestinal parasite in small ruminants worldwide. The problem is increasing due to the developing resistance of the parasite to commercially available anthelmintics. Medicinal plants with their biologically-active compounds may provide a viable alternative to synthetic anthelmintics, but sound scientific evaluation of such compounds is lacking. Artemisia annua is an effective antimalarial drug used currently in over 50 countries as the first line of treatment against chloroquine-resistant malaria. Its mode of action against malaria and cancer indicates that the plant and its main active ingredient (artemisinin) may also be used as an alternative way to control gastrointestinal parasites in small ruminants. The plant has naturalized in several areas of the world, but wild plants are photoperiod sensitive and low in artemisinin. New varieties developed in Switzerland and Brazil are late-flowering, have artemisinin concentrations varying from 0.5 to 1.0% w/w, and are more suitable to tropical areas afflicted by malaria. First-year trials in West Virginia have indicated that these new cultivars have potential for biomass accumulation and artemisinin production in the Appalachian region, and cultivars will be tested for their anthelmintic potential in goats. Research is ongoing to determine artemisinin fate and stability in ruminants, its effect on rumen microflora and dry matter digestibility, and artemisia herbage palatability to ruminants. This paper reviews past work with Artemisia spp. in small ruminants and presents preliminary results of our research with Artemisia annua in goats. If A. annua proves to be as valuable an anthelmintic as it is an anti-malarial, meat-goat (Capra hircus) farmers in Appalachia and other regions affected by haemonchosis will have a natural way to control gastrointestinal parasites, boosting the growth of the meat goat industry.