Extracts of Fl<i>ourensia cernua </i>reduce consumption of alfalfa pellets by sheep

TitleExtracts of Flourensia cernua reduce consumption of alfalfa pellets by sheep
Publication TypeJournal Article
Year of Publication2001
AuthorsEstell R.E., Tellez M.R., Fredrickson E.L., Anderson D.M., Havstad K, Remmenga M.D.
JournalJournal of Chemical Ecology
Date PublishedNovember 1, 2001
ARIS Log Number118536
Keywordsalfalfa pellets, consumption, fluorensia cernua extracts, sheep

Effects of three extracts (hexanes, ether and ethanol) from tarbush on intake of alfalfa pellets by lambs were examined in 2 experiments. Forty-five ewe lambs were fed 1 of 5 treatments for 5 days. Treatments were alfalfa pellets (CON) or alfalfa pellets plus ethanol carrier (CAR), hexanes extract (HEX), ether extract (ETH), or ethanol extract (ETOH). Extracts were applied to alfalfa pellets at the same concentration as in an equivalent amount of tarbush in experiment 1 and at 10-fold dilutions of that concentration in experiment 2. Treatments were isolated from 36 kg of tarbush leaves using a sequential extraction with hexanes, diethyl ether and 100% ethanol. Extracts were obtained in batches (3 kg of leaves in 7 liters of solvent) with constant mixing (22 hr per solvent), filtered, solvents removed using a rotary evaporator and residue resuspended in ethanol. Lambs received 640 g of alfalfa pellets each morning and intake was monitored during a 20-min interval. In experiment 1, mean intake by lambs during the 20-min interval was 361, 393, 204, 212 and 228 g for CON, CAR, HEX, ETH and ETOH, respectively (SEM = 28.9). All 3 extracts decreased intake (P < .0001) compared to CON or CAR. Intake did not differ among the 3 extracts (HEX, ETH and ETOH) nor between the 2 controls (CON and CAR). Mean intake did not differ among treatments in experiment 2 (468, 455, 389, 381 and 431 g for CON, CAR, HEX, ETH and ETOH, respectively; SEM = 30.5; P = .187). Because all 3 extracts decreased intake of alfalfa pellets at concentrations normally encountered in intact plants, several compounds are probably responsible for the low palatability and differential use of tarbush typically exhibited by livestock.