@article {JRN54922, title = {Controlling one-seed juniper saplings with small ruminants: What we{\textquoteright}ve learned}, journal = {Rangelands}, volume = {40}, year = {2018}, month = {10/2018}, pages = {129-135}, chapter = {129}, abstract = {

Protein supplements and polyethylene glycol increased juniper intake by small ruminants in all seasons except fall, when PSM concentrations were greatest. Terpenes were affected by season and sapling size, and were related to juniper intake by small ruminants. Small sapling browsing occurred most frequently in summer. Debarking of branches on taller saplings was greatest in spring. Ten years later, juniper kill ranged from 5-14\%. Growth suppression was still evident after 10 years; browsed saplings averaged 13 cm shorter than controls. Strategies to target grazing of one-seed juniper are more likely to succeed if aligned with periods when PSM are lowest.

}, keywords = {goats, phenology, plant secondary metabolites, protein supplementation, sheep, targeted grazing}, doi = {doi.org/10.1016/j.rala.2018.07.002}, url = {/files/bibliography/18-018.pdf}, author = {Richard E. Estell and Andr{\'e}s F. Cibils and S. A. Utsumi and Stricklan, D. and Butler, E. M. and Fish, A. I. and Amy Ganguli} } @article {JRN54560, title = {Defoliation of Flourensia cernua (tarbush) with high-density mixed-species stocking}, journal = {Journal of Arid Environments}, volume = {130}, year = {2016}, month = {04/2016}, pages = {62-67}, chapter = {62}, abstract = {

Interest in shrub use by livestock is increasing along with the rising demands placed on rangelands worldwide. Historically, Flourensia cernua (tarbush) has increased in the Chihuahuan Desert but receives limited use by cattle. Cattle, sheep and goats co-grazed eight 0.6 ha tarbush-dominated paddocks during two periods for up to nine days during two consecutive years. Cumulative tarbush defoliation across periods and years averaged 75.6\%, with a mean increase of 9.3\%/day (P \< 0.0001). Defoliation of individual shrubs varied from 5 to 99\% in 1989 and 0 - 100\% in 1990, indicating highly variable palatability among individual plants. Sheep lost 2.3 - 5.5 kg/hd (P \< 0.0001) across periods and years when forced to browse tarbush. In 1989, goats gained (P . 0.0345) 0.6 kg/hd in period 1, but the gain in period 2 was not significant (P . 0.2934). During 1990, goats lost 3.1 kg/hd (P . 0.0001) across periods. High-density mixed-species stocking of small areas for short time periods resulted in extensive tarbush use, primarily due to browsing by sheep and goats. Targeted use of tarbush for short time intervals may increase use of this highly nutritious forage and potentially serve as a form of biocontrol for this shrub.

}, keywords = {biocontrol, browsing, cattle, goats, sheep, shrubs}, doi = {10.1016/j.jaridenv.2016.03.013}, url = {/files/bibliography/16-008.pdf}, author = {Richard E. Estell and D.M. Anderson and D. K. James} } @article {JRN53932, title = {The changing role of shrubs in rangeland-based livestock production systems: Can shrubs increase our forage supply?}, journal = {Rangelands}, volume = {36}, year = {2014}, month = {04/2014}, pages = {25-31}, chapter = {25}, abstract = {

Projected global increases in ruminant numbers and loss of native grasslands will present a number of challenges for livestock agriculture. Escalated demand for livestock products may stimulate interest in using shrubs on western rangelands. A paradigm shift is needed to change the role of shrubs in rangeland ecosystems. Progress has occurred in identifying mechanisms to increase shrub use, but more solutions are needed to convert woody plants into red meat. Strategies for increasing shrub use could be important for rural communities to adapt to changing climate and shrub cover and for the livestock industry to adapt to predicted growth.

}, keywords = {cattle, goats, grasslands, secondary plant metabolites, sheep, woody plants}, url = {/files/bibliography/14-009.pdf}, author = {Richard E. Estell and Kris Havstad and Andr{\'e}s F. Cibils and D.M. Anderson and Scott T. Schrader} } @article {JRN53927, title = {Is differential use of Juniperus monosperma by small ruminants driven by terpenoid concentration}, journal = {Journal of Chemical Ecology}, volume = {40}, year = {2014}, month = {02/2014}, pages = {285-293}, chapter = {285}, abstract = {

We examined the relationship between volatile plant secondary metabolite concentrations and Juniperus monosperma herbivory by small ruminants. Two groups of animals (10 goats or 5 goats plus 4 sheep) browsed 16 paddocks (20 x 30 m) containing one-seed juniper for six days during two seasons. Juniper leaves were sampled from 311 saplings on the same day they were browsed. Saplings were categorized by size (short [\< 0.5 m], medium [0.5-1.0 m] or tall [\> 1.0 m]) and browsing intensity (light [\< 33\%], moderate [33-66\%] or heavy [\> 66\%]). Juniper bark was also collected from 12 saplings during spring. 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 a-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 short 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 the three defoliation categories (16.1 \± 0.4, 18.7 \± 0.5, and 21.2 \± 0.6 mg/g for heavy, moderate, and light, respectively). The smallest subset of terpenes able to discriminate (P \< 0.001) between heavy and light browsing intensity categories included eight compounds ([E]-\ß-farnesene, bornyl acetate, \&$\#$39;-eudesmol, endo-fenchyl acetate, y-cadinene, a-pinene, cis-piperitol, and cis-p-menth-2-en-1-ol).

}, keywords = {goats, herbivory, one-seed juniper, Oxygenated terpenes, Resource availability hypothesis, sheep, targeted grazing, terpenes}, doi = {10.1007/s10886-014-0389-1}, url = {/files/bibliography/14-006.pdf}, author = {Richard E. Estell and S. A. Utsumi and Andr{\'e}s F. Cibils and D.M. Anderson} } @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 {49882, title = {Increasing shrub use by livestock in a world with less grass}, journal = {Rangeland Ecology and Management}, volume = {65}, year = {2012}, month = {11/2012}, pages = {553-562}, chapter = {553}, abstract = {

Much of the world\&$\#$39;s rangelands are dominated by woody species. Competing land uses and continued encroachment of woody species into non-woody dominated rangelands have reduced grasslands in many parts of the world. Land use conversions to fuel and feed global populations, especially for increasing numbers of middle class people seeking broader, meat-based diets, will certainly continue. Halting and/or reversing further encroachment of woody species into grasslands is slow, expensive, and in some cases, not possible. Yet, global livestock numbers continue to increase to meet the growing demand for red meat and other livestock products. How do we reconcile a world with less grass and the concurrent increased demand for forages to feed livestock, either in extensive rangeland production systems or intensive confined feeding systems? Strategies and mechanisms are needed to safely enhance shrub use by ruminants in order to capitalize on a presently underutilized forage resource. Such strategies could provide important means for rural communities to adapt to changing land cover and climate.

}, keywords = {animal behavior, cattle, genetics, goats, plant secondary metabolites, sheep}, doi = {10.2111/REM-D-11-00124.1}, url = {/files/bibliography/12-031.pdf}, author = {Richard E. Estell and Kris Havstad and Andr{\'e}s F. Cibils and E.L. Fredrickson and D.M. Anderson and Scott T. Schrader and D. K. James} } @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} } @article {50327, title = {Effects of Eugenol, Alpha-Terpineol, Terpin-4-ol, and methyl eugenol on consumption of alfalfa pellets by sheep}, journal = {Small Ruminant Research}, volume = {73}, year = {2007}, month = {Septembe 10, 200}, pages = {272-276}, abstract = {Many secondary compounds are typically present in unpalatable shrubs on rangelands in the western United States. However, the relationship between intake by livestock and concentration of individual chemicals has been examined for very few of these compounds. Four experiments were conducted to examine effects of individual volatile compounds on intake of alfalfa pellets by lambs. Forty-five lambs (9 lambs/treatment) were individually fed alfalfa pellets with eugenol, {\textquoteright}-terpineol, terpin-4-ol, or methyl eugenol applied at one of five concentrations in an ethanol carrier. Treatments were multiples (0, 0.5, 1, 2, and 10X) of the concentration (X) of each compound on the leaf surface of Flourensia cernua. Treatment solutions were sprayed on alfalfa pellets (0.64 kg.lamb-1.d-1, DM basis), and consumption was measured during a 20-min interval for five days. A day effect (P < 0.001 for both linear and quadratic contrasts) 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 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, eugenol, {\textquoteright}-terpineol, terpin-4-ol, and methyl eugenol were not related to intake of alfalfa pellets by lambs under the conditions of this study.}, keywords = {diet selection, Herviory, intake, sheep, terpenes}, url = {/files/bibliography/07-026.pdf}, author = {Richard E. Estell and E.L. Fredrickson and D.M. Anderson and M.D. Remmenga} } @article {50544, title = {Effect of previous exposure of sheep to monoterpene odors on intake of alfalfa pellets treated with camphor or alpha-pinene}, journal = {Small Ruminant Research}, volume = {58}, year = {2005}, note = {This is not a duplicate; ARIS No. 151564 has same title but is an abstract submitted for a meeting. }, month = {April 1, 2005}, pages = {33-38}, abstract = {Lambs were subjected to odors of two monoterpenes (camphor and alpha-pinene) that decreased intake in a previous study to determine if exposure during feeding modified their effects on subsequent intake. Two experiments were conducted using a split-plot design and with 36 ewe lambs (mean BW = 23.1 and 42.2 kg in Exp. 1 and 2, respectively) group-fed alfalfa pellets (3.8\% of BW, DM basis) in enclosed portable buildings for 2 h each morning for 56 d. Nine lambs were randomly assigned to each of four buildings, and 25 g of camphor (Exp. 1) or 50 ml of alpha-pinene (Exp. 2) were placed in a mesh-covered container in the center of the feeder in two buildings immediately before feeding. After the 8-wk exposure period (phase 1), lambs were individually fed alfalfa pellets (640 g, DM basis) for 20 min each morning for 10 d (5-d adaptation, 5-d collection) in a metabolism building (phase 2). Treatments were sprayed on alfalfa pellets at levels representing the concentration of that chemical in Flourensia cernua or at 10-fold that concentration. Controls received the ethanol carrier only. During phase 2, lambs were fed in three groups (n = 12), stratified such that one lamb from each building received each treatment in each group. Lambs were housed as one group and fed alfalfa pellets at 4.7\% of BW (DM basis) except during the 20-min tests. No interactions with day were detected for intake during adaptation or collection periods for either chemical (P > 0.05); therefore, data were pooled across day. Exposure to the volatile aroma for 8 wk had no effect on intake during the subsequent 10-d interval for either monoterpene (P > 0.05). Moreover, intake during the collection period was not affected by treatment concentration (P > 0.05). Neither concentration of the terpene applied to alfalfa pellets nor previous exposure to the volatile aroma from camphor or alpha-pinene altered feed intake under the conditions of this study.}, keywords = {herbivory, intake, monoterpenes, olfaction, sheep}, url = {/files/bibliography/05-022.pdf}, author = {Richard E. Estell and E.L. Fredrickson and D.M. Anderson and Kris Havstad and M.D. Remmenga} } @article {50547, title = {Effects of gamma-terpinene, terpinolene, alpha-copaene, and alpha-terpinene on consumption of alfalfa pellets by sheep}, journal = {Journal of Animal Science}, volume = {83}, year = {2005}, month = {August 15, 2005}, pages = {1967-1971}, abstract = {Although plant secondary chemistry influences shrub consumption by free-ranging ruminants, the effects of many specific compounds on herbivory have not been examined. We conducted four experiments 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 gamma-terpinene, terpinolene, alpha-copaene, or alpha-terpinene 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.lamb-1.d-1, DM basis), and consumption was measured during a 20-min interval for 5 d. A day effect (P \< 0.02) was detected for gamma-terpinene on intake (P \< 0.0001 for both linear and quadratic contrasts). A treatment effect (P \< 0.02) was observed for alpha-copaene with intake on the 2X treatment lower than other treatments. No effect of terpinolene or alpha-terpinene on intake was detected in this study. None of the chemicals tested were strongly related to intake of alfalfa pellets by lambs under the conditions of this study. http://jas.fass.org/cgi/reprint/83/8/1967}, keywords = {diet selection, herbivory, intake, sheep, terpenes}, url = {/files/bibliography/05-013.pdf}, author = {Richard E. Estell and E.L. Fredrickson and D.M. Anderson and M.D. Remmenga} } @conference {50649, title = {Effects of {\~a}-terpinene, terpinolene, {\'a}-copaene, and {\'a}-terpinene on consumption of alfalfa pellets by sheep}, booktitle = {2004 Joint Annual Meeting, American Dairy Science Association/American Society of Animal Science/Poultry Science Association}, volume = {Vol. 82 (Suppl. 1)}, year = {2004}, month = {July 25, 2004}, pages = {34}, publisher = {Journal of Animal Science}, organization = {Journal of Animal Science}, address = {St. Louis, MO}, abstract = {Secondary chemistry influences shrub consumption by free-ranging ruminants. However, effects of many specific terpenes on herbivory have not been examined. 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 {\~a}-terpinene, terpinolene, {\'a}-copaene, or {\'a}-terpinene at one of five concentrations in an ethanol carrier. Treatments (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{\textperiodcentered}lamb-1{\textperiodcentered}d-1, DM basis), and consumption was measured during a 20-min 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 <0.02) was detected for intake with {\~a}-terpinene (P <0.0001 for both linear and quadratic contrasts). A treatment effect (P <0.02) was observed for {\'a}-copaene, with intake on the 2X treatment lower than other treatments. No effect of terpinolene or {\'a}-terpinene on intake was observed during the 20-min interval. None of the chemicals tested were strongly related to intake of alfalfa pellets by lambs under the conditions of this study.}, keywords = {alfalfa pellet intake, intake, lambs, sheep, terpenes}, author = {Richard E. Estell and E.L. Fredrickson and D.M. Anderson and Kris Havstad and M.D. Remmenga} } @article {50859, title = {Effects of four mono- and sesquiterpenes on consumption of alfalfa pellets by sheep}, journal = {Journal of Animal Science}, volume = {80}, number = {12}, year = {2002}, month = {December 1, 2002}, pages = {3301-3306}, abstract = {Effects of individual terpenes on alfalfa pellet intake by lambs were examined in four experiments. Forty-five lambs (9 lambs/treatment) were individually fed alfalfa pellets sprayed with either camphene, myrcene, caryophyllene oxide, or beta-pinene at one of five concentrations (one terpene per experiment). Treatments (0, .5, 1, 2, and 10X) were multiples of the concentration (X) of a specific terpene in tarbush. Terpenes were applied to alfalfa pellets (.64 kg.lamb-1.d-1, DM basis) and consumption wa measured during a 20-min interval for 5 d. Lambs were maintained and fed alfalfa pellets in one group (except during 20-min tests) at a mean total daily intake of 4.7\% of BW (DM basis). Camphene and caryophyllene oxide tended to decrease intake (linear contrasts were P = .0651 and P = .0504, respectively), while myrcene and beta-pinene exerted no effect on consumption of alfalfa pellets by lambs during the 20-min interval. Camphene and caryophyllene oxide may be involved in the differential herbivory of individual tarbush plants by livestock.}, keywords = {alfalfa pellets, consumption, individual terpenes, sheep}, doi = {10.2527/2002.80123301x}, url = {http://jas.fass.org/cgi/reprint/80/12/3301}, author = {Richard E. Estell and E.L. Fredrickson and D.M. Anderson and Kris Havstad and M.D. Remmenga} } @article {50985, title = {Extracts of Flourensia cernua reduce consumption of alfalfa pellets by sheep}, journal = {Journal of Chemical Ecology}, volume = {27}, number = {11}, year = {2001}, month = {November 1, 2001}, pages = {2275-2285}, abstract = {

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.

}, keywords = {alfalfa pellets, consumption, fluorensia cernua extracts, sheep}, doi = {10.1023/A:1012235121852}, url = {/files/bibliography/01-021.pdf}, author = {Richard E. Estell and M.R. Tellez and E.L. Fredrickson and D.M. Anderson and Kris Havstad and M.D. Remmenga} } @article {51068, title = {Effect of individual terpenes on consumption of alfalfa pellets by sheep}, journal = {Journal of Animal Science}, volume = {78}, number = {6}, year = {2000}, month = {June 1, 2000}, pages = {1636-1640}, abstract = {

We examined effects of five individual terpenes on alfalfa pellet intake of lambs. In each experiment, 45 lambs were individually fed alfalfa pellets sprayed with either p-cymene, alpha-humulene, 1,8-cineole, 3-carene, or sabinene at one of five concentrations. Treatment levels (0, .5, 1, 2, and 10X) were multiples of the concentrations (X) of specific terpenes in tarbush that were related to differential herbivory by livestock in previous studies. Treatments were applied to alfalfa pellets (.64 kg/lamb/d, DM basis), and consumption during a 20-min interval was measured for 5 d. Lambs were adapted to handling and 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 4.7\% of BW (DM basis). None of the five compounds examined decreased pellet consumption during the 20-min interval. These five mono- and sesquiterpenes do not appear to be responsible for differential herbivory of individual tarbush plants by livestock.

}, keywords = {alfalfa pellets, herbivory, individual terpenes, lambs, sheep}, url = {/files/bibliography/00-008.pdf}, author = {Richard E. Estell and E.L. Fredrickson and D.M. Anderson and Kris Havstad and M.D. Remmenga} } @conference {51067, title = {Fluorensia cernua extracts decrease intake of alfalfa pellets by sheep}, booktitle = {2000 Joint Meeting, American Society of Animal Science/American Dairy Science Association}, volume = {78}, number = {Suppl. 1}, year = {2000}, month = {2000}, pages = {113}, publisher = {Journal of Animal Science}, organization = {Journal of Animal Science}, abstract = {

Our objective was to evaluate the effects of 3 extracts (hexane, ether and ethanol) isolated from tarbush on intake of alfalfa pellets by sheep. In each of 2 experiments, 45 ewe lambs received 1 of 5 treatments for 5 d. Treatments were alfalfa pellets (CON) or alfalfa pellets plus ethanol carrier (CAR), hexane extract (HEX), ether extract (ETH) or ethanol extract t(ETOH). Treatments were isolated from tarbush leaves (36 kg) using a sequential extraction of hexane, diethyl ether and 100\% ethanol. Extractions (3 kg of leaves in 7 L of solvent, constant mixing, 22 h per solvent) were filtered, solvents removed using a rotary evaporator and resuspended in ethanol. Lambs were offered 640 g of alfalfa pellets (DM basis) and intake was monitored during a 20-min interval each morning. Extracts were applied to alfalfa pellets at the same concentration as in tarbush in Exp. 1, and at 10-fold dilutions in Exp. 2. Lambs were adapted to handling and individual pen feeding for 10 d and maintained and fed alfalfa pellets (4.7\% of BW, DM basis) as one group except during 20-min tests. All 3 extracts reduced intake by lambs in Exp. 1 ( P \< .0001) compared to CON or CAR. Mean intake during the 20-min period was 361, 393, 204, 212 and 228 g for CON, CAR, HEX, ETH and ETOH, respectively (SEM=28.9). Intake did not differ between CON and CAR, nor among HEX, ETH and ETOH. Mean intake in Exp. 2 was not different (468, 455, 389, 381 and 431 g for CON, CAR, HEX, ETH and ETOH, respectively; SEM =30.5; P =.187). Three fractions containing mixtures of compounds of increasing polarity were equally effective in decreasing intake of alfalfa pellets at concentrations encountered in intact tarbush plants; thus, several compounds are probably involved in the low palatability of this shrub exhibited by livestock.

}, keywords = {alfalfa pellets, extracts, Fluorensia cernua, intake, sheep, tarbush, treatments}, author = {Richard E. Estell and M.R. Tellez and E.L. Fredrickson and D.M. Anderson and Kris Havstad and M.D. Remmenga} } @article {51212, title = {Effects of volatile compounds on consumption of alfalfa pellets by sheep}, journal = {Journal of Animal Science}, volume = {76}, year = {1998}, month = {1998}, pages = {228-233}, 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, cts-jasmone, {\^a} -caryophyllene, borneol, or -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-lamb^-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 concentrations on intake was observed for camphor (P \<.02) -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 -pinene and camphor concentrations on pellet consumption suggest that these monoterpenes may partially explain differential herbivory of individual tarbush plants by livestock.

}, keywords = {diets, intake, sheep, terpenoids}, doi = {10.2527/1998.761228x}, url = {/files/bibliography/609.pdf}, author = {Richard E. Estell and E.L. Fredrickson and M.R. Tellez and Kris Havstad and Shupe, W. Larry and D.M. Anderson and M.D. Remmenga} } @article {51439, title = {Effects of organic solvents on use of tarbush by sheep}, journal = {Journal of Chemical Ecology}, volume = {20}, number = {5}, year = {1994}, month = {1994}, pages = {1137-1142}, abstract = {

Tarbush (Flourensia cernua DC) is a native perennial shrub prevelant in many parts of the Chihuahuan desert. Ruminants have exhibited limited use of tarbus leaves and new leaders as a forage during the summer growing season. Efforts to increase use of tarbush by lambs, through spraying with various organic solvents were unsuccessful. probably because of the highly variable response. However, complete immersion of tarbush in organic solvents (acetone and ethanol) increased (P\< 0.01) tarbush use by ram lambs when compared to unaltered tarbush using organic solvents enhanced acceptability of tarbush to sheep.

}, keywords = {Flourensia cernua, herbivory, leaf surface, organic solvents, sheep, tarbush}, doi = {10.1007/BF02059749}, url = {/files/bibliography/416.pdf}, author = {Richard E. Estell and D.M. Anderson and Kris Havstad} }