@article {JRN55387, title = {Diet selection of raramuri criollo and angus x hereford crossbred cattle in the Chihuahuan Desert}, journal = {Journal of Arid Environments}, volume = {205}, year = {2022}, month = {7/4/2022}, pages = {104823}, abstract = {Strategies to help producers cope with unpredictable forage production associated with low and variable precipitation patterns on arid rangelands are needed, particularly if global warming trends continue as projected. One option is to identify cattle biotypes compatible with less productive shrubby landscapes. One such biotype is the Raramuri Criollo (RC) from the Copper Canyon of northern Mexico. This small-framed animal exhibits travelling behaviors that allow it to exploit vegetation at a greater distance from water, although it is unknown whether RC have dietary preferences that differ from European breeds typically raised in the southwestern U.S.A. We examined diet selection of RC vs. desert adapted Angus x Hereford (AH) crossbreds typical of the region using DNA metabarcoding to determine the proportion of plant species in fecal samples. Fecal samples were collected from 10 cows of each breed in two adjacent pastures during two seasons (growing and dormancy; four weeks per season) for three consecutive years. Dominant plant species in fecal samples of both cattle breeds were Atriplex canescens (four-wing saltbush), Hoffmannseggia glauca (hog potato), Hopia obtusa (vine mesquite), Setaria leucopila (plains bristlegrass), Sporobolus spp. (S. contractus, S. flexuosus, and S. giganteus), Pleuraphis mutica (tobosa), and Bouteloua eriopoda (black grama), which is consistent with previous studies in the region using different techniques for assessing dietary plant composition of other breeds of cattle. Only a few differences were detected between breeds. Compared to AH, fecal samples from RC tended to contain a higher proportion of mesquite and Yucca spp. (P < 0.07) and less Ephedra spp. (P < 0.06). The only grass species that differed between breeds was black grama (P < 0.05), with AH fecal samples containing about twice as much as RC cows (\~{}8\% vs. 4\%). This finding could have important implications for conservation of black grama in the Chihuahuan Desert.}, keywords = {beef cattle, diet selection, DNA metabarcoding, Raramuri Criollo}, doi = {10.1016/j.jaridenv.2022.104823}, url = {files/bibliography/22-016.pdf}, author = {Richard E. Estell and S. Nyamuryekung{\textquoteright}e and D. K. James and S. Spiegal and Andr{\'e}s F. Cibils and Amy L. Gonzalez and Matthew M. McIntosh and Kirsten B. Romig} } @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 {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} } @article {51213, title = {Relationship of tarbush leaf surface terpene profile with livestock herbivory}, journal = {Journal of Chemical Ecology}, volume = {24}, number = {1}, year = {1998}, month = {January 1, 1998}, pages = {1-12}, abstract = {

Tarbush (Flourensia cernua DC.) is a Chihuahuan Desert shrub with a resinous leaf surface containing terpenes that may affect livestock herbivory. Cattle, sheep, and goats were densely stocked in paddocks containing tarbush in two consecutive years for six to nine days and defoliation of 160 plants was recorded daily. Plants were categorized as exhibiting high or low defoliation. Leaves were collected from these plants the third year for chemical analysis. A selection procedure was used to generate two variable sets closely related to defoliation category. One set contained 14 variables (dry matter, ash, -pinene, sabinene, 3-carene, p-cymene, limonene, camphor, bomeol, cis-jasmone, {\^a} -caryophyllene, alpha-humulene, ledene, and flourensadiol) and the other set contained 14 unidentified compounds. When subjected to multivariate analysis, each group distinguished between the two defoliation categories (P \<0.001 and P \<0.0019 for known and unknown variable sets, respectively). These data support the hypothesis that leaf surface chemistry of individual tarbush plants is related to extent of defoliation by livestock.

}, keywords = {diet selection, Epicuticular wax, Flourensia cernua, leaf surface chemistry, monoterpenes, sesquiterpenes}, doi = {10.1023/A:1022399426352 }, url = {/files/bibliography/608.pdf}, author = {Richard E. Estell and E.L. Fredrickson and D.M. Anderson and Kris Havstad and M.D. Remmenga} } @article {51322, title = {Tarbush leaf surface terpene profile in relation to mammalian herbivory}, year = {1996}, note = {NOT A DUPLICATE OF RECORD $\#$474}, month = {1996}, pages = {237-241}, publisher = {US Forest Service}, edition = {Gen. Tech. Rep. INT-GTR}, abstract = {

Cattle, sheep and goats were densely stocked in pad- docks containing tarbush (Flourensia cernua DC) for six to nine days and defoliation of 160 plants was recorded daily during two years. Plants were separated into high, moderate or low defoliation categories. Leaves were collected from plants during the same stage of maturity during the third year. Leaf surface compounds were extracted with ethanol and mono- and sesquiterpenes were ana-lyzed using gas chromatography/ion trap mass spectrometry. A set of 11 variables was identified that appeared most closely related to plant defoliation categories: dry matter, ash, limonene, camphor, borneol, a copaene, B caryophyllene, a pinene, p-cymene, cis-jasmone and caryophyllene oxide concentrations. This group distinguished among all three defoliation categories (P \< 0.03) when subjected to multivariate analysis. These data support the hypothesis that leaf surface chemistry is related to degree of defoliation of individual tarbush plants by livestock.

}, keywords = {diet selection, Epicuticular wax, Flourensia cernua, leaf surface chemistry, monoterpenes, sesquiterpenes}, url = {/files/bibliography/512.pdf}, author = {Richard E. Estell and E.L. Fredrickson and D.M. Anderson and Kris Havstad and M.D. Remmenga} } @conference {51505, title = {Effect of feeding ewe lambs a 15\% tarbush pellet pre-and post-weaning on subsequent diet selection of tarbush}, booktitle = {46th Annual Meeting of the Society for Range Management}, year = {1993}, month = {1993}, pages = {No. 131}, abstract = {

Tarbush, a deciduous shrub, has rapidly increased its dominance in Chihuahuan Desert grasslands. Encroachment of tarbush has led to a concomitant degradation of forage production, wildlife habitat value, soil stability and watershed quality. Therefore, sustainable methods to reduce the encroachment of tarbush are highly desirable. Since tarbush is comparable to alfalfa in nutrient density, we believe increasing livestock intake of tarbush will improve diet quality, while decreasing tarbush competitiveness. A sheep study was initiated to determine dietary preference for tarbush and influence of previous tarbush exposure on preference. Twenty ewe lambs (10/treatment) were assigned at birth to receive cither tarbush or alfalfa (15\%, dry matter basis) in a sorghum-based pelleted creep feed. Lambs were pen-fed this diet 60 days pre-weaning and 60 days post-weaning. No differences existed between treatments in ration consumption. After 120 days, each group was placed in one of two adjacent 45 m2 paddocks dominated by tarbush and burrograss (Scleropogon brevifolius). An assessment of individual diet selection was determined visually from an elevated platform at three minute intervals for 4 hours following sunrise on 2 consecutive days, with lambs being alternated to the other paddock on the second day. The observations were repeated every 30 days until dormancy of tarbush. Between each observation period, lambs were pastured in 10 ha paddocks with a similar species composition as the study paddocks. Over the course of the study, lambs were recorded eating tarbush during approximately 35\% of feeding observations. Initially, previous exposure to tarbush appeared to avert lambs from tarbush, yet this aversion wan not apparent during later periods.

}, keywords = {diet selection, ewe lambs, tarbush pellet}, author = {Shupe, W. Larry and E.L. Fredrickson and Kris Havstad and Richard E. Estell} }