Maturity of coastal bermudagrass and alfalfa affects ruminal in situ and total tract dry matter and phosphorus disappearance in cannulated steers

摘要: Summary Variability of phosphorus (P) availability among forage species and plant maturity is largely ignored when formulating ruminant diets. To determine if variability in P changes with and/or maturity, ruminal situ total (ruminal + post-ruminal) dry matter (DM) disappearance (PD) from alfalfa (ALF; Medicago sativa) coastal bermudagrass (CB; Cynodon dactylon) harvested at four stages was measured cattle. Forages were hand clipped 14, 21, 28 35 days after first cutting. Ruminal DM (DMD) PD 24 h incubation Dacron bags. Total tract DMD using the mobile nylon bag technique. Disappearance greater (p ≤ 0.05) rumen than post-rumen for both regardless maturity; however, 80 g PD/kg 35-day ALF (9% PD) 224 g CB (38% occurred post ruminally. Alfalfa disappeared to a extent showed 5% 14 days 13% more compared grass. decreased 5.4% 14- while decrease far CB, 12.4%. Results this study indicate that nutritionists should take into account calculating diets; these details can be used aid precise rations reduce fecal-phosphorus excretion environment.