Effect of Cotton Seed, Soybean or Rape Seed Cake as a Protein Supplement with Ammonia (Urea) Treated Rice Straw on Feed Cost for Growing Crossbred Heifers

Twenty four crossbred heifers were divided into four equal groups. Control group was fed on untreated rice straw and a concentrate mixture to meet the protein requirements for 500 g gain per day. The other three groups were fed cotton seed, soybean or rapeseed cake to meet l/3rd of the protein requirements with ammonia (urea) treated straw fed ad lib. and the animals received daily 2 kg green berseem and 30 g common salt and mineral mixture, to determine the most economical ration. The intake of DM and DDM did not vary significantly among groups, however, the DMI through roughage portion was significantly higher for treated straw rations. The DM digestibility coefficients were 52.27, 52.38, 52.04 and 50.83 respectively for control, cotton seed, soybean and rapeseed cake fed groups. The CP digestibility was significantly (P<0.05) higher in control and cotton seed cake fed groups than in other groups. The average daily gain in control group was highest followed by rapeseed cake, cotton seed cake or soybean cake groups. It is concluded that cotton seed or rapeseed cake may be fed with urea treated straw to economize the feed cost per kg gain.