@article {JRN52696, title = {Coping with shrub secondary metabolites by ruminants}, journal = {Small Ruminant Research}, volume = {94}, year = {2010}, month = {10/2010}, pages = {1-9}, chapter = {1}, abstract = {

Rangelands throughout the world contain varying but often substantial proportions of shrubs. Shrubs are generally heavily chemically defended, and herbivores must either contend with their plant secondary metabolites (PSM) or avoid a significaant component of the available forage. Browsing ruminants are exposed to thousands of chemicals in infinite combinations and concentrations that are constantly changing both temporally and spatially. The success with which a herbivore navigates this complex environment is in part attributed to its ability to cope with PSM. Plant secondary metabolites can affect a number of physiological and metabolic processes (e.g., altered microbial activity, reduced digestion, compromised acid/base balance, toxicity), although negative consequences to the herbivore range from harmless to lethal, depending factors such as dose, animal species, plane of nutrition, and physiological state. Herbivores have a variety of intertwined mechanisms to cope with consumption of PSM, ranging from physiological (e.g., salivary proteins, detoxification pathways) to behavioral (e.g., avoidance, regulation of intake below critical threshold, cautious sampling, altering size and pattern of feeding bouts, diet switching, consuming diverse and/or complementary diets). Secondary compounds may affect requirements for nutrients (e.g., protein, minerals, and glucose) and water, and may alter basal metabolic rate. Energy requirements may also increase to accommodate increased travel to water and supplementation sites to counter these negative effects, particularly on arid rangelands.

}, keywords = {foraging behavior, herbivory, intake, plant secondary metabolites, ruminants, secondary chemistry, shrubs}, doi = {10.1016/j.smallrumres.2010.09.012}, url = {/files/bibliography/10-033.pdf}, author = {Richard E. Estell} } @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} } @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} } @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} } @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} } @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} } @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} } @conference {51408, title = {Effects of tarbush ingestion on intake, digesta kinetics, in situ digestion, ruminal fermentation, and nitrogen balance of sheep consuming low quality tobosa grass diets}, booktitle = {Journal of Animal Science}, volume = {74 (Suppl. 1)}, year = {1995}, month = {1995}, pages = {Abstract 205}, abstract = {Tarbush (Flourensiacernua) represents a substantial biomass in the Chihuahuan Desert. Two studies were conducted to assess intake, in situ digestion, passage rate, ruminal fermentation, and nitrogen balance of sheep fed a low quality tobosa (Hilariamutica) diet containing up to 30\% tarbush leaves. Tarbush was harvested and air dried, and leaves were separated from stems. In Exp. 1, 16 ruminally cannulated Polypay x Rambouillet lambs (avg BW = 46 kg) were individually fed (twice daily) ground (2.54 cm) tobosa (5.9\% CP, 80\% NDF; DM basis) substitued with 0, 10, 20, or 30\% (DM basis) tarbush (18.9\% CP, 33\% NDF) leaves ad libitum for 28d. In Exp. 2, 24 Polypay x Rambouillet wethers (avg BW = 47 kg) in metabolism crates were allotted to one of the four treatments described above (n = 5) or 26\% ground alfalfa (n = 4). Sheep were fed ad libitum for 11 d and then restricted to 1\% of BW for 11 d to equalize intake. In Exp. 1, DMI for 20 and 30\% tarbush treatments was greater (P = .0049) during week 3 than 0 and 10\% treatments. Molar butyrate proportions (P = .0032) and total VFA concentrations (P = .0064) were greater for the 30\% tarbush treatment than other treatments. Sheep fed 30\% tarbush had greater (P < .0046) ruminal ammonia concentrations than sheep fed other diets at 6, 8, and 12 h postfeeding. In Exp. 2, all treatments resulted in similar but negative N retentions (-2.4, -2.2, -2.8, -2.0, and -1.5 g/d for sheep consuming 0, 10, 20, or 30\% tarbush or alfalfa, respectively). Because only 30\% tarbush elicited measurable responses in Exp. 1 (based on ruminal ammonia dn total VFA concentrations), nutrients contained by tarbush (especially CP) did not appear to be completely available to sheep. Low DMI observed in Exp. 2 was likely due to secondary compounds in tarbush and may partly explain why no differences in N balance were observed in Exp. 2.}, keywords = {intake, nitrogen balance, rumen ammonia, sheep, tarbush ingestion, tobosa grass}, author = {D. King and Richard E. Estell and E.L. Fredrickson and Kris Havstad and Wallace, J.D. and L. W. Murray} } @article {51555, title = {Effects of milk intake on forage intake and performance of suckling range calves}, journal = {Journal of Animal Science}, volume = {69}, year = {1991}, month = {1991}, pages = {899-904}, abstract = {

A study to examine the relationships between milk intake, forage intake, and performance of Hereford-Angus suckling range calves was conducted during July, August, and September of 1984 and 1985. Twenty calves were used each year. The study was conducted at the Red Bluff Research Ranch located 56 km west of Bozeman, Montana. Average daily gain, milk intake (MI), forage digestibility, and fecal output (FO) were measured at 28-d intervals, beginning when the average calf age was 66 +/- 4 d. Milk intake was estimated using weigh-suckle-weigh techniques. Total fecal collections were used to measure FO. Forage digestibility and rates of passage were determined using nylon bag in situ techniques and external markers in ruminally cannulated calves of the same age. Fecal output by calves increased as body weight and age increased. Milk intake was higher (P\< .05) in 1985 than in 1984, but FO was higher (P\< .01) in 1984 than in 1985. Fecal output by calves was negatively correlated to MI in July (r = -.62; P\< .05) and August (r = -.56; P\< .05). No significant correlations were detected between MI and ADG (P\> .10). Forage intake estimates were derived from FO, rate of passage, and in situ digestibility values. During July, calves consumed .3 kg more forage for each kilogram of reduction in fluid MI (P\< .05). In both August and September, calves consumed .6 kg more forage for each kilogram of reduction in fluid MI (P\<.10). Calves maintained similar digestible energy (DE) intake both years, although the source of DE varied.

}, keywords = {calves, forage, intake, Milk, suckling}, url = {/files/bibliography/707.pdf}, author = {Ansotegui, R.P. and Kris Havstad and Wallace, J.D. and Hallford, D.M.} }