Influence of grass source and legume level on net flux of nutrients across splanchnic tissues in sheep

摘要: Abstract Crossbred catheterized wethers (20 months old; 45 kg BW, SE 0.7) consumed ad libitum warm ((W) bermudagrass; Cynodon dactylon ) or cool ((C) ryegrass-wheat mixture; Lolium multiflorum and Triticum aestivum , respectively) season grass hay with 0%, 20% 40% legume ((L) alfalfa; Medicago sativa ). Legume, W C had 54%, 80% 68% NDF 17%, 14% 10% CP, respectively (DM basis). Apparent digestible energy intake was 3.22, 3.42, 3.66, 3.23, 3.57 3.67 (SE 0.208) Mcal day −1 apparent N 17.6, 20.2, 23.4, 10.1, 14.0 17.3 1.09) g for W:0% L, W:20% W:40% C:0% C:20% L C:40% respectively. Splanchnic bed oxygen consumption (306, 364, 380, 261, 316 383 mmol h ; P = 0.02) portal-drained viscera (PDV) releases of alpha-amino (24.8, 37.6, 38.6, 24.4, 38.4 41.7 0.04) propionate (14.4, 19.4, 20.5, 14.3, 23.6 21.1 respectively; 0.08) were greater than without. However, splanchnic net glucose similar among treatments. In conclusion, dietary inclusion effects on tissue fluxes nutrients regardless source, which differed in concentrations CP but not intake. These results suggest that potential improvement animal performance by substituting grass, mature ruminants, would be attributable to change extra-splanchnic availabilities (based the difference between consumption), amino acids glucose.