Effects of volatile compounds on consumption of alfalfa pellets by sheep.

Abstract

We examined the effects of six volatile compounds on alfalfa pellet consumption by lambs. In each experiment, 45 lambs were individually fed alfalfa pellets sprayed with a selected compound (camphor, limonene, cis-jasmone, beta-caryophyllene, borneol, or alpha-pinene) at one of five concentrations. Treatment concentrations were multiples (0, .5, 1, 2, and 10) of the concentration of a specific compound (X) that was related to differential herbivory of tarbush by livestock in previous studies. Treatments were applied to alfalfa pellets (.64 kg x lamb(-1) x d(-1), DM basis), and consumption was measured during a 20-min interval each morning for 5 d. Lambs were adapted to handling procedures and the pelleted diet (without treatments) for 10 d. Lambs were maintained and fed (approximately 4.5 to 5% of BW) as one group except during 20-min tests. A negative linear effect of treatment concentration on intake was observed for camphor (P < .02) and alpha-pinene (P < .01), and a quadratic response was detected for borneol (P < .02). The other three compounds had no discernible effect on consumption. Although volatile compounds generally had only minor influences on consumption, the negative influences of alpha-pinene and camphor concentrations on pellet consumption suggest that these monoterpenes may partially explain differential herbivory of individual tarbush plants by livestock.

The effects of increasing the level of dietary wormwood (Artemisia montana Pampan) on intake, digestibility, N balance and ruminal fermentation characteristics in sheep

“…Hirasa and Takemasa (1998) reported that while some EO have inhibited bacterial growth (Hirasa and Takemasa, 1998), others seem to have improved nutrient utilization. When different levels of individual EO were sprayed on alfalfa pellets in sheep diets, intake was linearly reduced by camphor and a-pinene, quadratically increased by borneol and unaffected by h-caryophyllene, cis-jasmone and limonene (Estell et al, 1998). However a subsequent study found no effect of camphor or a-pinene on intake (Estell et al, 2005).…”

Plant bioactives for ruminant health and productivity

“…Behaviour and feed intake may also be effected by aroma. Estell et al (1998) demonstrated that terpene volatiles could effect feed intake in sheep. Varying levels of camphor (4) and a-pinene (5) (Fig.…”

Essential oils and aromatic plants in animal feeding – a European perspective. A review.

“…[3,5] Estell et al [47] reported that terpene volatiles could aff ect feed intake in sheep, which is quite important when grazing in Mediterranean pastures. Better knowledge of specifi c chemical interactions with feed intake would be useful for altering feeding management.…”