@article {49867, title = {Effects of adding protein, condensed tannins, and polyethylene glycol to diets of sheep and goats fed one-seed juniper and low quality roughage}, journal = {Small Ruminant Research}, volume = {112}, year = {2013}, month = {04/2013}, pages = {56-68}, chapter = {56}, abstract = {

The biochemical mechanisms that limit voluntary intake of one-seed juniper by browsing ruminants are not well understood. Twelve Rambouillet ewes (78 \± 2.3 kg BW) and 12 Boer-Spanish does (54 \± 1.4 kg BW) were used in a split-plot sequence design to investigate the effects of adding protein, quebracho tannins (QTs), and polyethylene glycol (PEG) on one-seed juniper intake and preference and on ruminal VFA and plasma AA concentrations. Animals received sudangrass hay and isoenergetic basal diets (4 does and 4 ewes/diet) with either rumen degradable (RDP) or rumen undegradable (RUP) protein (12.5\% CP) or no additional protein (control, 5\% CP) during four 15-d periods. The control, RDP, and RUP diets were considered the main plot, whereas the four supplement treatments were analyzed as the split-plot effects. Period 1 allowed for adaptation to basal diets and served as a baseline phase. In periods 2-4, animals were offered juniper leaves and twigs (period 2), juniper plus QT (10\% of basal diet; period 3), and juniper plus QT plus PEG (50 g/animal; period 4). Juniper intake by sheep and goats was not affected (P \> 0.88) by RDP or RUP when animals were first exposed to juniper, but marginally increased (P \< 0.10) in period 4 (QT + PEG) regardless of the basal diet. Prior exposure to juniper did not affect (P = 0.61) the preference ratio for juniper, but goats had higher preference ratio for juniper (P \< 0.01) when receiving PEG (period 4). Concentrations of total VFA tended to increase in sheep (P = 0.10) and goats (P = 0.14) fed protein supplements and molar proportions shifted toward acetate for goats fed RDP and RUP (P = 0.07) and to butyrate for sheep fed RDP (P = 0.01). Initial juniper exposure (period 2) elevated concentrations of acetate, propionate, and butyrate (P \< 0.01), but the effect was extinguished in periods 3 and 4 with addition of QT (P \< 0.05). Supplementation with PEG transiently mitigated the depressor effect of QT on acetate, propionate, and butyrate concentration at 12 h post juniper feeding (P \< 0.01). RDP in goats and to a greater extent RUP in sheep increased plasma concentrations of various AA, especially the branched chained Val, Ile, and Leu (P \< 0.05). Plasma concentrations of several AA, including Met, Cyst, Glu, Gly, Gln, Asn, Thr, Ser, and Phe, decreased with ingestion of juniper (period 2) and juniper plus QT (period 3). Concentrations of some AA that were depressed by ingestion of juniper and QT were partially restored with supplemental PEG (P \< 0.05). Protein, terpenes, tannins, and PEG interacted to influence rumen VFA and plasma AA, which were related to intake of juniper and basal diets.

}, keywords = {goats, juniper, rumen degradabe protein, rumen undegradable protein, sheep, terpenes}, doi = {10.1016/j.smallrumres.2012.09.006}, url = {/files/bibliography/13-012.pdf}, author = {S. A. Utsumi and Andr{\'e}s F. Cibils and Richard E. Estell and S. Soto-Navarro and Cheng, L. and Hallford, D.M.} } @article {50150, title = {Seasonal changes in one seed juniper intake by sheep and goats in relation to dietary protein and plant secondary metabolites}, journal = {Small Ruminant Research}, volume = {81}, year = {2009}, month = {2009/02/19}, pages = {152-162}, abstract = {Seasonal variation in plant secondary metabolites (PSM) can influence voluntary intake levels of one-seed juniper (Juniperus monosperma Englem. Sarg.) of sheep and goats. Supplemental nutrients could mitigate the deterrent effects of juniper PSM. We determined the concentration of mono-and sesqui- terpenes, total phenolics and condensed tannins in one-seed juniper leaves in summer, fall, winter, and spring, and tested their effects on juniper intake of 12 Western White Face ewes (74.9 {\textpm} 1.23 kg) and 12 Boer-Spanish does (46.7 {\textpm} 1.25 kg) fed isoenergetic diets (1.6\% BW) with no supplemental protein (Control, 5\% CP) or with addition of a rumen degradable (RDP, 12.5\% CP) or undegradable (RUP, 12.5\% CP) protein supplement. Animals were fed unrestricted amounts of freshly harvested juniper branches for 30 min and short-term juniper intake was determined for 10 d per season. Total terpenes, total phenolics, and condensed tannins varied across seasons (P<0.05), and were positively correlated to each other (P<0.05). Juniper intake was greater for goats than sheep (P<0.05), and twice as high for supplemented vs. control animals (P<0.05). Juniper intake in the fall, when levels of plant secondary metabolites were highest, was 41, 58, and 52\% less than in summer, winter, and spring (P<0.05), respectively. Supplements with RDP and RUP promoted different patterns of juniper intake among seasons (P<0.05), herbivores (P<0.05), and individual animals (P<0.05). This study suggests that supplemental protein can increase voluntary intake of one-seed juniper of small ruminants during seasons when plant secondary metabolite levels are low. Proteins of different degradability appear to affect seasonal patterns of juniper intake differently.}, keywords = {goats, journal, juniper, protein supplements, ruminant, secondary metabolites, sheep}, url = {/files/bibliography/09-006.pdf}, author = {S. A. Utsumi and Andr{\'e}s F. Cibils and Richard E. Estell and S. Soto-Navarro and D. VanLeeuwen} } @conference {50292, title = {Effects of one-seed juniper and polyethylene glycol on intake, rumen fermentation, and plasma amino acids in sheep and goats fed supplemental protein and tannins.}, booktitle = {Journal of Animal Science}, volume = {86}, number = {(E-Supple. 2)}, year = {2008}, month = {July 7, 2008}, pages = {224}, abstract = {We tested the effect of polyethylene glycol (PEG) on juniper and total intake, rumen fermentation, and plasma amino acids (AA) of 12 does and 12 ewes fed sudangrass and basal diets containing 10\% quebracho tannins with no protein supplement (Control; 5\% CP) or high rumen degradable (RDP 15\% CP) or undegradable (RUP 15\% CP) protein supplement. After 15 days of exposure to non-restrictive amounts of juniper leaves, sudangrass, and basal diets (period 1), animals received an additional 50 g of PEG for a second 15-d period. Blood and ruminal fluid samples were collected on the last 2 d of each period to determine AA and VFA ({\textmu}M). Analyses followed a split-plot design with periods with or without PEG treated as a sub-plot factor. Juniper intake did not differ between species (P > 0.05) or supplements (P > 0.05), but increased with addition of PEG in period 2 (Period 1 vs. 2: 4.3 vs. 10.8 g/kg 0.75; P < 0.01). Total intake and intake of sudangrass and basal diets were higher for sheep than goats (P < 0.01) and differed between supplements and periods (supplement x period, P < 0.05). Polyethylene glycol stimulated higher intakes of basal diet for Control and RDP, and of sudangrass for RUP. Total VFA was higher for sheep than goats (P < 0.05) and decreased from period 1 to period 2 with supplemental PEG in sheep (70.6 vs. 62.1; species x period, P < 0.05) and with RDP (67.3 vs. 58.6; supplement x period, P < 0.05). Acetate and propionate differed between periods with or without PEG in the same manner as total VFA. Total AA and some individual AA differed between species (sheep > goats), supplements (RUP = RDP > Control), and periods (P < 0.05). Increased juniper intake with PEG in period 2 was associated with lower plasma GLY, THR, SER, ASP, MET, GLU, PHE, CYST, GLN, ORN, LYS, HIS, and TRP. Polyethylene glycol increased juniper intake and decreased several plasma AA when tannin-rich foods with varying CP were fed.}, keywords = {abstract, goats, one-seed juniper, polyethylene glycol, rumen, sheep}, author = {S. A. Utsumi and Andr{\'e}s F. Cibils and Richard E. Estell and S. Soto-Navarro and Hallford, D.M.} } @conference {50290, title = {Effects of one-seed juniper on intake, rumen fermentation, and plasma amino acids in sheep and goats fed supplemental protein}, booktitle = {Journal of Animal Science}, volume = {86}, number = {E-supple. 2}, year = {2008}, month = {July 7, 2008}, pages = {223}, abstract = {We tested the effect of feeding one-seed juniper on total intake, VFA profile, and plasma amino acids (AA) of 12 does and 12 ewes fed sudangrass and a basal diet with no protein supplement (Control; 5\% CP) or rumen degradable (SBM; RDP 15\% CP) or undegradable (FM; RUP 15\% CP) protein supplement. After 15 d of adaptation to sudangrass and basal diets (period 1), animals received one-seed juniper leaves in addition to sudangrass and basal diets during a second 15-d period. Each food was fed separately during 3-h periods at 10\% of previous day intake. Blood and ruminal fluid samples were collected on the last 2 d of each period to determine plasma AA, VFA ({\textmu}M), and rumen pH. Analyses followed a split-plot design with periods with or without juniper as a sub-plot factor. Juniper intake did not vary between species (P = 0.54) or supplement treatments (P = 0.93; 4.7 g/kg0.75). Total intake (TI), basal diet intake (BDI), and sudangrass intake (SGI) were unaffected by supplements, were higher for sheep than goats (P < 0.01), and decreased with juniper feeding in period 2 (P < 0.01). Total intake, BDI, and SGI for periods 1 and 2 were 54.9 vs. 47.6, 36.7 vs. 31.5, and 18.2 vs. 11.5 g/kg0.75, respectively. Total VFA, acetate (Ac), and propionate (Pr) increased with juniper in period 2 (P < 0.01; period 1 vs. 2, VFA: 63.9 vs. 79.4; Ac: 47.5 vs. 60.5; Pr: 9.3 vs. 11.7). Rumen pH averaged 6.4 and did not differ between supplements, species, or periods. Total AA and some individual AA differed between supplements (RUP = RDP > Control), species (goats > sheep), and decreased with juniper feeding in period 2 (P < 0.05). Juniper intake in period 2 was associated with decreased plasma ALA, GLY, THR, SER, ASP, MET, GLU, PHE, CYST, TYR, and TRP. These data suggest one-seed juniper in sheep and goat diets depresses intake, but may increase VFA and requirements for certain amino acids.}, keywords = {abstract, goats, juniper, one-seed, sheep}, author = {S. A. Utsumi and Andr{\'e}s F. Cibils and Richard E. Estell and S. Soto-Navarro and Hallford, D.M.} } @conference {50395, title = {One seed juniper intake by sheep and goats supplemented with degradable or by-pass protein}, booktitle = {Society for Range Management Meeting Proceedings}, year = {2007}, month = {February 9-16, 2}, pages = {Paper No. 448}, address = {Reno/Sparks, NV}, abstract = {Successful prescribed grazing of one seed juniper (Juniperus monosperma Englem. Sarg.) with sheep and goats may depend on identifying times of the year when juniper terpenoid levels are less likely to deter herbivory and could be contingent on the use of protein supplements to help animals detoxify terpenes and boost intake. We conducted pen trials with sheep and goats to determine if individual juniper intake varied seasonally (summer, fall, winter, or spring) or was affected by the amount and kind of crude protein (CP) in the diet. Twelve Ramboullet ewes and 12 Spanish-boer goats were offered a basal diet of sudangrass or bermudagrass hay with either no protein added (Control diet: 5\% CP), or with soybean meal (degradable CP: DCP) or fishmeal (by-pass CP:BPCP) to achieve two treatment diets with 12.5\% CP each. Diets were offered at 1.6\% of body weight (BW) to each animal for 10 days of adaptation and 10 days of data collection in each season. Juniper trials were a 30 min feeding bout on juniper branches (175g) attached to wooden stands (0.8 m height). Juniper intake per unit of BW (J1) varied amoung herbivore species. J1 varied among diets (P=0.02) was highest for animals receiving the DCP and BPCP supplements and lowest for control animals. J1 also varied among seasons, intermediate in spring and summer, and lowest during the fall. Sheep and, especially, goats could be used in prescribed grazing programs to suppress juniper re-invasion. Great suppression could be expected from goats browsing during winter, provided that protein levels are sufficient to allow animals to detoxify terpenoids.}, keywords = {by-pass protein, goats, juniper, sheep}, author = {S. A. Utsumi and Andr{\'e}s F. Cibils and Richard E. Estell and S. Soto-Navarro} } @conference {50396, title = {Sheep and goats as tool to suppress juniper encroachment: Influence of stocking density and mixed grazing during summer}, booktitle = {Society for Range Management Annual Meeting}, year = {2007}, month = {February 9-16, 2}, pages = {Paper No. 447}, address = {Reno/Sparks, NV}, abstract = {Grazing trials were conducted to evaluate the use of prescribed grazing by sheep and goats to suppress one-seed juniper (Juniperus monosperma Englem. Sarg.) sapling reinvasion. A 2x2 factorial experiment was conducted with Goats (G) or Goats + Sheep (G+S) at high or low stocking densities (SD). Ten crossbreed Angora nannies (1.1 AU) or 5 nannies of the same breed mixed with 4 Ramboullet ewes (1.1 AU) grazed either 1 juniper invaded plot of 20 x 30 m for 6 days (LD) or 6 similar subplots of 10 x 10 m for 1 day (HD) in each of 2 blocks. Animals grazed from sunrise to sunset, were penned at night and received a protein supplement (45\% CP) at a rate of 0.4\% BW, daily. No effect of SD, herbivore (G, G+S), or their interaction was found on juniper utilization. Animals removed on average 38.3\% of the length of marked juniper sapling branches. Understory grazing intensity differed between G or G+S (P=0.02) and SD (P=0.05) treatments. G+S removed 71.3 \% of the available herbaceous biomass whereas G removed 64.7 \%. Greater understory grazing intensity was observed under LD (70.4 \%) compared to HD (65.0 \%). Goats spent more time feeding on juniper compared to sheep (Goats: 24.5\%, Sheep: 7.7\%, P<0.01), whereas the opposite occurred with herbaceous vegetation (Goats: 76.0 \%, Sheep: 92.3 \%; P< 0.01). Stocking density did not influence time spent feeding juniper or herbaceous understory (P=0.08). Goats in HD and LD grazing treatments spent similar time feeding on juniper (P=0.09). Prescribed high density grazing with goats alone, rather than goats and sheep, could promote acceptable juniper sapling use along with lower damage on herbaceous vegetation. Juniper sapling responses to the treatments imposed in this study will be monitored through time.}, keywords = {goats, grazing, one-seed juniper, sheep}, author = {S. A. Utsumi and Andr{\'e}s F. Cibils and Richard E. Estell} } @conference {50514, title = {One Seed Juniper Intake by Sheep and Goats Supplemented with Degradable or By-Pass Protein}, booktitle = {New Mexico Section Range Science Winter Meetings}, year = {2006}, month = {January 12-13, 2}, address = {Las Cruces, NM}, abstract = {Re-invasion of one seed juniper previously cleared woodlands is a concern of range managers throughout the southwestern United States. Prescribed browsing with sheep and goats could be used as a juniper control method. Success with this tool may depend on improving the herbivore{\textquoteright}s ability to detoxify plant terpenoids in order to induce levels of herbivory that are likely to suppress juniper growth and recruitment. Our objective was to test the effect of two kinds of protein supplementation on juniper consumption by sheep and goats. One seed juniper intake was compared in sheep and goats fed diets varying in amount and quality of crude protein during three seasons (summer, fall, and winter). Goats consumed significantly more juniper than ewes and protein supplements more than doubled juniper intake by both sheep and goats. Goats aggressively defoliated juniper branches, while sheep consumed leaves in a more selective manner. In summary, sheep and goats have potential for use to suppress juniper sapling encroachment. Goats consumed more juniper and protein supplements had a stronger influence on juniper intake of goats.}, keywords = {goats, juniper, protein, sheep}, author = {S. A. Utsumi and Andr{\'e}s F. Cibils and Richard E. Estell and S. Soto-Navarro and Ross, T.T. and S. Ivey and Giacomini, M. and M.K. Petersen and S.H. Cox and M. Rubio} } @conference {50511, title = {Sheep and goat grazing as a tool to mange encroachment of one-seed juniper (Juniperus monosperma Engelm. Sarg.)}, booktitle = {III Simposium Internacional de Pastizales}, year = {2006}, month = {August 9-11, 200}, pages = {13}, address = {Chihuahua, Mexico}, abstract = {The efficacy of using prescribed grazing by sheep and goats to suppress one-seed juniper re-invasion could be improved by providing adequate nutrients to help animals detoxify plant terpenes. We analyzed the terpenoid chemistry of one-seed juniper leaves and conducted feeding trials with 12 Ramboullet ewes and 12 Boer-Spanish nannies to determine if juniper intake (JI) varied seasonally (summer, fall or winter) or was affected by the amount and kind of crude protein (CP) available to detoxify terpenes. Diets were a sudangrass (Sorghum sudanensis) hay with either no protein added (Control diet: 5\% CP), or with soybean meal (degradable CP: DCP; 12.5\% CP) or fishmeal (by-pass CP: BPCP; 12.5\% CP). Juniper trials were conducted for 10 days in each season and consisted of a 30 min feeding bout on juniper branches (175g) attached to wooden stands (0.8 m height). Juniper leaves contained 51 terpenoids, 14 represented 95 \% of the total terpenoid amount, and {\'a}-pinene was the most abundant terpene (65\%). Juniper intake was greater for goats (0.54g kgBW-1) than Sheep (0.23g kgBW-1), and was higher for animals receiving the DCP (0.5g kgBW-1) and BPCP (0.41g kgBW-1) supplements than for control animals (0.25g kgBW-1). JI also varied among seasons (winter: 0.54g kgBW-1; summer: 0.38g kgBW-1; fall: 0.23g kgBW-1). Sheep and, especially, goats could be used in prescribed grazing programs to suppress juniper re-invasion. Greater suppression could be expected from goats browsing during winter, provided that protein levels are sufficient to allow them to detoxify terpenes efficiently.}, keywords = {goat, sheep, uniper}, author = {S. A. Utsumi and Andr{\'e}s F. Cibils and Richard E. Estell and S. Soto-Navarro} }