@proceedings {JRN53998, title = {Relationship between one-seed juniper terpene concentration and herbivory by small ruminants}, volume = {91}, year = {2013}, month = {07/2013}, pages = {553}, publisher = {Journal of Animal Science}, address = {Indianapolis, IN}, abstract = {

Plant secondary metabolite affect the amount of use by herbivores for serveral woody species.\  We examined the relationship between terpenoid concentrations and Juniperus monosperma herbivory by small ruminants.\  The study was part of a larger effort in which goats (n = 10) or mixed species (5 goats and 4 sheep) were allotted to 16 plots (20 \× 30 m) containing one-seed juniper for 6 d during 2 seasons at 2 stocking rates. Juniper leaves were sampled from 311 saplings on the same day they were browsed. Saplings were categorized by size (small [\<0.5 m], medium [0.5-1.0 m] or tall [\>1.0 m]) and browsing intensity (low [\<33\%], moderate [33-66\%] or heavy [\>66\%] herbivory). Juniper bark was also collected from 12 saplings during spring. Leaves and bark were analyzed for terpenoids with gas chromatography-mass spectrometry. Terpene data were pooled across species and stocking rate and ANOVA was conducted for season, sapling size, and herbivory level. The volatile profile of one-seed juniper leaves and bark consisted of 65 and 55 compounds, respectively. Total estimated terpenoid concentrations in leaves and bark were 18.3 \± 0.3 and 8.9 \± 0.8 mg/g, respectively, and the dominant terpene in both tissues was \α-pinene (11.1 \± 0.2 and 7.6 \± 0.7 mg/g, respectively). Total terpenoid concentration was greater (P \< 0.001) in spring than summer (20.6 \± 0.5 vs. 16.7 \± 0.3 mg/g, respectively) and lower (P \< 0.001) in small saplings than medium or tall saplings (16.5 \± 0.6 vs. 19.8 \± 0.4 and 19.5 \± 0.4 mg/g, respectively). Total concentration also differed (P \< 0.001) among all 3 browsing categories (16.1 \± 0.4, 18.7 \± 0.5, and 21.2 \± 0.6 mg/g for heavy, moderate, and light herbivory, respectively). Approximately 42\% of the variation in browsing intensity could be explained (P \< 0.001) by 12 compounds ([E]-\β-farnesene, cis-sabinene hydrate, bornyl acetate, \γ-eudesmol, germacrene A, \γ-cadinene, \α-pinene, [Z]-\β-ocimene, terpin-4-ol, cispiperitol, cis-p-menth-2-en-1-ol, and camphene hydrate). Our results indicate that the terpene profile of one-seed juniper is related to sapling size, season, and degree of use by sheep and goats.

}, keywords = {goat, sheep, terpene}, author = {Richard E. Estell and S. A. Utsumi and Andr{\'e}s F. Cibils and D.M. Anderson} } @article {50026, title = {Measurement of monoterpenes and sesquiterpenes in serum, plasma, and rumen fluid from sheep}, journal = {Animal Feed Science and Technology}, volume = {158}, year = {2010}, pages = {104-109}, abstract = {Studies involving the consumption, metabolism, and elimination of terpenes by small ruminants consuming terpene-laden shrubs as well as those exploring the potential for natural products as rumen modifiers could benefit from a procedure that measures terpenes in both blood and rumen fluid and that is suitable for either serum or plasma. The objective of this study was to modify an existing procedure for plasma utilizing solid phase extraction/gas chromatography, and extend its use for measurement of structurally diverse mono- and sesquiterpenes in three fluids (serum, plasma, and rumen fluid) from sheep. Generally, terpene recovery was lower from rumen fluid than from serum or plasma, although the extent and direction of differences varied among chemicals. Fourteen terpenes (camphene, {\ss}-pinene, a-terpinene, p-cymene, cis-{\ss}-ocimene, 1,8-cineole, {\textquoteright}-terpinene, terpinolene, linalool, camphor, longifolene, {\ss}-caryophyllene, a-humulene, and caryophyllene oxide) were recovered from serum at approximately 100\%. Recovery from rumen fluid was lower than for serum or plasma for most terpenes, but eight terpenes (p-cymene, 1,8-cineole, cis-sabinene hydrate, terpinolene, borneol, terpin-4-ol, a-terpineol, and caryophyllene oxide) were recovered at near 100\%. Yet, 15 terpene recoveries were below 75\% (tricyclene, a-pinene, camphene, sabinene, {\ss}-pinene, myrcene, 2-carene, 3-carene, a-terpinene, cis-{\ss}-ocimene, limonene, {\textquoteright}-terpinene, longifolene, {\ss}-caryophyllene, and a-humulene). Oxygenated monoterpenes were typically recovered in greater quantities and hydrocarbon monoterpenes were least effectively recovered with this method. The procedure is suitable for measurement and recovery adjustment of terpenes from serum, plasma, and rumen fluid of sheep.}, keywords = {plasma, recovery, rumen fluid, ruminants, serum, sheep, shrub, terpene}, url = {/files/bibliography/10-04.pdf}, author = {Richard E. Estell and S. A. Utsumi and Andr{\'e}s F. Cibils} } @conference {50326, title = {Effects of individual terpenes and terpene mistures on intake of lambs}, booktitle = {American Society of Animal Science}, volume = {85}, number = {Suppl. 1}, year = {2007}, month = {July 9, 2007}, pages = {287-288}, abstract = {Rangeland degradation due to shrub encroachment is a major concern to livestock producers and land managers in the western United States and in arid and semiarid regions worldwide. Most invasive shrubs contain secondary compounds that reduce their consumption by herbivores, but knowledge concerning the effects of specific compounds is limited. Four experiments were conducted to determine the effects of individual terpenes or mixtures of monoterpenes or sesquiterpenes on intake by lambs. After a 10-day adaptation period with untreated alfalfa pellets, lambs were individually fed treated alfalfa pellets for 20 min. each morning for 5 days. Five treatments (0X, .5X, 1X, 2X, and 10X; multiples of the concentrations of the same terpenes in Flourensia cernua) were applied to alfalfa pellets (637 g, DM basis) in an ethanol carrier. Except during the 20-m,in test, lambs were maintained outdoors and fed untreated alfalfa pellets (total mean intake = 4.7\%) in Exp. 1 and 4 because of greater intake of OX than other treatments on day 1 and lower intake for the 10XZ treatment on day 1 and 2. A trend for decreased intake (g/kg BW) as concentration of the sesquiterpene mixture increased was observed. Although there was a tendency for a sesquiterpene mixture to decrease intake, and the monoterpene mixture did not appear to affect intake by lambs.}, keywords = {alfalfa, alfalfa pellet, intake, lambs, shrubs, terpene}, author = {Richard E. Estell and E.L. Fredrickson and D.M. Anderson and M.D. Remmenga} } @conference {50438, title = {Antiherbivory Compounds on the Leaf Surface of Intact and Resprouted Tarbush}, booktitle = {2006 Joint Annual Meeting, American Society of Animal Science, American Dairy Science Association}, volume = {J. Animal Sci. Vol. 84, J. Dairy Sci. Vol. 89}, number = {1}, year = {2006}, month = {July 9-13, 2006}, pages = {22}, address = {Minneapolis, Minnesota}, abstract = {Shrub encroachment into desert grasslands of the southwestern United States is a serious problem, resulting in loss of forage and rangeland productivity. Flourensia cernua (tarbush) is one such shrub contributing to the decline of Chihuahuan Desert grasslands. Our previous research has shown tarbush consumption by sheep and goats to be negatively related to leaf surface concentration of individual terpenes and epicuticular wax. Concentrations of antiherbivory compounds such as terpenes change with plant age and phenology. Our objective was to alter the vegetative state and potential palatability of tarbush by clipping intact plants and generating resprouts. We hypothesized resprouts would invest fewer resources into antiherbivory compounds and therefore have lower concentrations of volatile chemicals such as terpenes than intact plants. Ninety tarbush plants were randomly selected, and all biomass within 10 cm of the soil surface was removed from 45 plants during winter dormancy. Leaves were collected the following summer during active growth from the canopy of intact controls and resprouts. Leaf surface volatiles were extracted in ethanol and analyzed by gas chromatography-mass spectroscopy to determine their identity and concentration. Data were transformed to natural logarithms and subjected to univariate analysis of variance and stepwise discriminate analysis. Of the 87 compounds present on tarbush leaves, 35 were greater in canopy samples and 16 were greater in regrowth samples based on univariate analysis (P < 0.05). Mean concentration of total volatiles on canopy leaves tended to be less (P = 0.0622) than that of regrowth (3642 vs 4684 {\textquoteright}g/g DM). Nine compounds in the discriminate analysis explained 95\% of the variation between canopy and regrowth samples. In contrast to our hypothesis, lower cumulative concentration of volatile compounds in canopy than regrowth samples suggests repsrouts may be less vulnerable to herbivory than old growth tarbush. However, animal studies are needed and effects on other classes of secondary compounds must be examined.}, keywords = {regrowth, shrub, terpene}, author = {Richard E. Estell and E.L. Fredrickson and M.D. Remmenga} } @conference {50545, title = {Effects of eugenol, terpin-4-ol, alpha-terpineol, and methyl eugenol on consumption of alfalfa pellets by sheep}, booktitle = {2005 Annual Meeting of American Society of Animal Science}, volume = {83 (Suppl. 1)}, year = {2005}, month = {July 24, 2005}, pages = {274}, address = {Cincinnati, OH}, abstract = {Secondary compounds present in shrubs on rangelands in the western United States are often aversive to livestock. However, effects of many of these compounds on intake have not been individually tested. Four experiments were conducted to examine effects of individual terpenes on alfalfa pellet intake by lambs. Forty-five lambs (9 lambs/treatment) were individually fed alfalfa pellets sprayed with either eugenol, terpin-4-ol, alpha-terpineol, or methyl eugenol at one of five concentrations in an ethanol carrier. Treatments (0, 0.5, 1, 2, and 10X) were multiples of the concentration (X) of a specific terpene on the leaf surface of Flourensia cernua. Terpenes were applied to alfalfa pellets (0.64 kg.lamb1.d1, DM basis), and consumption was measured during a 20min interval for 5 d. Lambs were adapted to handling and individual pen feeding for 10 d and were maintained and fed alfalfa pellets in one group (except during 20 min tests) at a mean total daily intake of 3.9\% of BW (DM basis). A day effect (P< 0.0001) was detected for intake in all four experiments, but no day x treatment interactions were observed (P> 0.05). The day effect was generally due to lower intake of alfalfa pellets on day 1, except for the methyl eugenol experiment, in which lambs consumed more pellets on day 1. No treatment effects were observed (P> 0.05) for any of the four chemicals tested; thus, none of these chemicals were strongly related to intake of alfalfa pellets by lambs under the conditions of this study.}, keywords = {herbivory, intake, terpene}, author = {Richard E. Estell and E.L. Fredrickson and D.M. Anderson and M.D. Remmenga} }