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.

TitleEffects of one-seed juniper and polyethylene glycol on intake, rumen fermentation, and plasma amino acids in sheep and goats fed supplemental protein and tannins.
Publication TypeConference Paper
Year of Publication2008
AuthorsUtsumi S.A., Cibils AF, Estell RE, Soto-Navarro S., Hallford D.M.
Conference NameJournal of Animal Science
Date PublishedJuly 7, 2008
ARIS Log Number223494
Keywordsabstract, goats, one-seed juniper, polyethylene glycol, rumen, sheep
AbstractWe 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 (µM). 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.