Ruminal Dry Matter and Protein Degradability of some Concentrate Ingredients Using Nylon Bag Technique

The ruminal disappearance of DM and CP and effective DM and CP degradability for groundnut cake, heat treated groundnut cake at 115 (Gl), 120 (G2), and 125°C (G3) for 30 min., cotton seed cake, solvent extracted cotton seed cake, barley, wheat bran, maize and maize gluten meal were studied by nylon bag technique at incubation periods varying from 36–48 h using three adult crossbred calves each fitted with a rumen cannulae. The calves were fed a maintenance diet of wheat straw and concentrate in the ratio of 65: 35. Heat treatment of GNC increased the rate of degradation as well as effective degradability for DM. Effective DM degradability (EDMD) at the k value of 0.05 hr⁻¹, was highest (74.5%) for wheat bran and the lowest (34.0%) for maize gluten meal. CP degradation rate at similar k value was highest (0.062) for G2 and lowest (0.016) for maize gluten meal. The effective CP degradability (ECPD) followed a similar pattern as that of EDMD i.e. the highest value (80.6%) for wheat bran and lowest value (22.4%) for maize gluten meal. Thus a positive correlation (r=0.90) existed between EDMD and ECPD. Heat treatment of groundnut cake increased the ECPD. Heat treated groundnut cake (G3) had the highest and solvent extracted cotton seed cake the lowest RDP content on DM basis. The per cent UDP followed a reverse trend. However among the cereal grains and grain byproducts maize gluten meal had the highest and wheat bran the lowest UDP content whereas maize gluten meal had the highest and the maize grain the lowest RDP content.