Evaluation of the feeding value of two tropical cereal straws, maize stover, rice straw and their botanical fractions by nylon and mobile bag technique

Degradability characteristics of dry matter (DM), protein free DM (PFDM) and nitrogen (N) were estimated in maize stover, rice straw and their botanical fractions using the nylon bag technique. True intestinal digestibility of the intact feed protein (TID) was also estimated using the mobile bag technique. The results indicated that cereal straws and their botanical fractions have substantial variation in the extent and rate at which DM, PFDM and N were degraded in the rumen. The protein values of Total amino acid absorbed from the small intestine (AAT) , Protein balance in the rumen (PB) and TID ranged from 49 to 81 g kg-1DM, in PBV from –89 to – 61 g kg-1 DM and TID of 34 to 69 percent DM in both straws and their botanical fractions. The predicted dry matter intake (DMI) value for whole maize stover was slightly higher (5.2 kg DM d-1) than whole rice straw (4.9 kg DM d-1). High variations (4.5 to 6.1 kg DM d-1 for maize stover and 4.5 to 5.7 kg DM d-1 for rice straw) were observed within the two cereal straw botanical fractions. It was concluded that the two cereal straws are of very low feeding value and to increase their production potential improvement method strategies like chemical treatment and/or supplementation are inevitable.