170 likes | 519 Views
Artemisia species in small ruminant production: potential antioxidant and anthelmintic effects. Jorge F.S. Ferreira, Ph.D. USDA-ARS, Appalachian Farming Systems Research Center July 11, 2009. Background on Artemisia spp. Genus named after Artemis the goddess of the hunt.
E N D
Artemisia species in small ruminant production: potential antioxidant and anthelmintic effects. Jorge F.S. Ferreira, Ph.D.USDA-ARS, Appalachian Farming Systems Research Center July 11, 2009
Background on Artemisia spp. • Genus named after Artemis the goddess of the hunt. • Genus has over 300 species. • Several medicinals (dewormers, insecticides, antimalarials, etc). • A. absinthium (wormwood)used for absinthe, Amish dewormer (thujone, santonin, etc.). • A. annua – produces artemisinin, a commercial antimalarial in >50 countries.
Plants as sources of anthelmintic compounds Rahmann & Seip 2007. Bioactive forage and phytotherapy to cure and control endo-parasitediseases in sheep and goat farming systems – a review of current scientific knowledge
Plants as sources of antioxidants • Antioxidants neutralize harmful O2-based free radicals in the body, retarding cell aging, reducing bad cholesterol, boosting the immune system, and helping us (and animals) cope with a range of diseases.
FLAVONOIDS ARE MAJOR PLANT-PRODUCED ANTIOXIDANTS Flavonoids are polyphenolic molecules produced by plants. They can be found in flowers, fruits, leaves, and roots. Some are polymerized into large molecules known as “tannins”.
Our work with the Oxygen Radical AbsorbanceCapacity (ORAC)test. Abbreviations: TAC = total antioxidant activity EtOH = ethanol Br. = Brazilian Ch. = Chinese Sw. = Swiss FD = freeze dried OD = oven dried
Lipophilic fraction less than 8% of the TAC of ORAC Note: some Appalachian trees (e.g., sumac) have EXTREMELY high total antioxidant capacity (TAC) and deserve to be investigated for animal nutrition.
How do antioxidant flavonoids relate to anthelmintics? “Laboratory tests have determined that flavonoids are effective against malaria, Trypanosoma (Chagas disease), Leishmania, Cryptosporidium, and Toxoplasma.” Note: Quercetin is a major flavonoid found in Artemisia spp., including A. annua (Lai et al. 2007. J. Chrom B 848:215-225).
However, flavonoids from Artemisia spp. and Paw-paw have not yet been tested scientifically.
HOW ARE COMMERCIAL HERBAL DEWORMERS DOING? Molly’s Herbal dewormers : wormwood, mugwort, garlic, black walnut, pumpkin, fennel, hyssop, thyme, and stevia. Formula 1: 19 g/animal (630 mg/kg) once daily for 3 days, and repeated after 62 days Formula 2: 19g/animal every 7 days except during the week Formula 1 was given. Notes: 1.Recommended doses could have been low (diluted) to reduce FECwith the plants used in the study. 2.Treatment regimen was not long enough. 3. Others have found herbals with wormwood, fennel, gentian, psyllium, and quassia (and the Ivomec control) to have varying efficacies depending on breeds of sheep and goats (Swartz et al. 2009. J. Anim. Sci. 83, Suppl 1/J, pg.64).
HOW ARE CONDENSED TANNINS DOING? Although lespedeza hay worked (condensed tannins?) against Haemonchus (44%)+Trichostrogylus (54%), lespedeza was used from 50-75% of the diet for 21 days for a reduction in FEC, while 75% was needed to reduce adult worms in 74%. Note: establishment of lespedeza in central Appalachia has proven difficult, and other plants (with and without tannins) must be investigated.
Artemisia spp. as an anthelmintic in the literature(most work done in the last 9 years) -Mostly in India, China, Africa, and South America, but snail hosts exist in the USA. -Losses of $2-3 billion/year worldwide.
Results of Artemisia/artemisinin research so far. • Artemisinin not toxic to goats at 10.0 mg/kg, and to gerbils at 200 mg/kg, but these dose had not effect on Haemonchus FEC (Turner and Ferreira, 2005). • Artemisia annua did not impair rumen microorganisms and digestibility in vitro (Turner and Ferreira 2005). • A. annua high in protein (27%), aminoacids (18%), potassium (26K ppm), and antioxidant activity (ORACTAC) > 1,000 (Brisibe, Ferreira et al. 2008). • Artemisinin was fairly resistant to rumen (basic and acidic pH) and was found in blood and feces of goats fed 33 mg/kg (Ferreira & Gonzalez 2008).
Results of Artemisia/artemisinin research so far (Cont.) • Artemisinin at 200 mg/kg for 5 days failed to reduce Haemonchus in gerbils after 5 days of treatment (Squires, Zajac, Ferreira, unpublished). (not yet tested in Fasciola or coccidia-infected animals). • A. annua and A. ludoviciana fed to Haemonchus-infected goats (450 g/day + suppl.) for 4-6 days reduced FEC in 4% and 34% (NS) 14 DAT started, while untreated animals had a 32% FEC increase. • A. afra had the highest ORACTAC (>2,000) of tested artemisias so far and should be investigated against Haemonchus. • The lipophilic fraction of ORAC often less than 8% of the TAC of the plant. Oven dried similar to freeze dried ORACTAC levels. • Other compounds produced by Artemisia annua and the crude ethanolic extracts are being tested in vitro (Foster, Bligh, Ferreira).
Challenges to face • In vivo goat studies are time-consuming and expensive. • In vitro bioassays are laboring and not always available when needed. In vivo gerbil studies take time, money, and not always replicate in vivo results reported for sheep and goats. • Doses to be tested depend on LD50 data, which is not always available. • Time allowed for the assay (5 days max) not long enough to produce an effect. • Research on antioxidant flavonoids effect on animal resilience to GIN (immune system) lacks in literature. • Results depend on plant (growth stage, production of active metabolite), nematode (species and life stage), and host type (sheep or goat) and breed. • Individual differences also account for lack of significant results (5-10 animals per treatment). QUESTIONS ?