191 Evaluation of Diverse Cool-Season Grass Mixtures with red Clover on Ruminal Fermentation in Continuous Culture

Abstract Dual-flow continuous culture fermenters were used to evaluate the impacts of forage mixtures on ruminal fermentation. Diets (DM basis) contained 40% red clover combined with 1) 60% orchardgrass (OG); 2) 30% + meadow fescue (MF); 3) 20% Kentucky bluegrass (KYBG); or 4) 15% perennial ryegrass (PRG). Treatments randomly assigned in a 4 x Latin square design. Each 10-d period included 7-d adaptation and 3-d sampling period. (110 g DM/d) added across feedings/d (33% each, 0700 h 1600 h; 17% 0820h 1720 h). Fermenter pH was recorded continuously for 10-d. Methane measured d 7-10 at 0630 1530 h. Effluent samples collected 8-10. Results analyzed using PROC GLIMMIX SAS significance P ≤ 0.05. Apparent digestibility DM, OM, NDF, ADF greatest (P 0.05) receiving KYBG, followed by PRG. DM OM OG MF less than KYBG 18.0% 19.6%, respectively. Fermenters spent amount time under 5.8 (avg. 15.5 h/d; = 0.0004). Acetate:propionate acetate butyrate:propionate ratios greater (4.09 4.71) PRG (4.03 4.65; < 0.0001). Water soluble carbohydrate concentration effluent least (0.80 mg/ mL; 0.05). output (116.8 mg/dL; 0.0001) that (13.7 mg/dL), (31.7 (11.9 mg/dL) which did not differ from one another. These results suggest diets containing more digestible having benefit decreased methane output.