Seasonal dynamics of dry matter, crude protein and cell wall digestion in total plant, leaves and stems of common buffelgrass (Cenchrus ciliaris)

This study was conducted to estimate and compare, seasonally, the nutrient content and the rate and extent of digestion of dry matter (DM), crude prot ein (CP) and cell wall (CW) of total plant (TP), leaves (L) and stems (S) o f buffelgrass (Cenchrus ciliaris L). Plants were sampled in a four-ha pastu re at Marin, N. L. County, Mexico, during fall of 1998, winter, spring and summer of 1999. The in situ technique was used to estimate effective degrad ability of DM (EDDM), crude protein (EDCP) and cell wall (EDCW), using rume n fistulated sheep. Crude protein content in forage was significantly highe r in summer than in other seasons; however, cell wall and its derivatives ( cellulose, hemicellulose and lignin) were significantly lower in summer. Cr ude protein content was higher in L than S, but CW was lower in L than in S . Moreover, EDDM, EDCP and EDCW were significantly higher in summer than in other seasons and also were higher in L than in S. Highly significant corr elation coefficients between CP, CW and effective degradability data may in dicate that when CP increased and CW decreased, EDDM, EDCP and EDCW increas ed. The nutrient content and digestion parameters of digestion of buffelgra ss varied among seasons, being summer and fall higher in nutrient digestion and spring and winter lower. Furthermore, leaves of buffelgrass should be considered different entities than stems when determining nutritional quali ty.