Nutritive Value and Utilization of Perennial Grasses Intercropped with Soybean Fodder by Crossbred Heifers in Humid-subtropics of Himachal Pradesh

A study was carried out to investigate the nutritive value and utilization of hybrid sorghum and perennial grass species viz. setaria (Setaria anceps) and hybrid napier when intercropped with soybean by growing Jersey crossbred heifers. Fifteen growing crossbred heifers (Jersey${\times}$Red Sindhi) of between 7-10 months age and pre-trial average body weight of 49-50 kg were divided on the basis of weight in to three treatment groups viz. $T_1$-hybrid sorghum+soybean, $T_2$-setaria+soybean and $T_3$-hybrid napier+soybean in a completely randomized block design. Intercropped forages were harvested fresh, chaffed and mixed before they were offered to the heifers. Chemical composition of the herbage, dry matter intake (DMI), body weight gain and nutrient digestibility co-efficients were estimated. The herbage mixtures had crude protein (CP) content in the range of 11.87 to 13.86% and ether extract (EE) contents were 2.91 to 3.11%, respectively. The herbage mixtures were rich in minerals (ash). The gross energy (kcal/g DM) was higher in hybrid napier+soybean, while hybrid sorghum+soybean and setaria+soybean herbage mixtures had lower value for gross energy. The hybrid sorghum+soybean and setaria+soybean herbage mixtures had higher contents of NDF, ADF, cellulose, lignin and silica as compared to that of hybrid napier+soybean herbage mixture. The heifers fed hybrid napier+soybean herbage mixture had significantly (p<0.05) higher $DMI\;g/kg\;W^{0.75}$ ($97.41{\pm}4.34$) as compared to hybrid sorghum+soybean ($88.31{\pm}2.66$) and setaria+soybean ($79.29{\pm}1.06$) herbage mixtures. Nutrients digestibility, DCP percent, DCP intake and nitrogen balance were significantly (p<0.05) higher in the heifers fed on hybrid napier+soybean herbage mixture. There was a significant (p<0.05) difference among different herbage mixtures in TDN. The heifers on setaria+soybean herbage mixture had lower average body weight gain (g/day) than those on hybrid sorghum+soybean and hybrid napier+soybean herbage mixtures. Data obtained in this experiment demonstrated that herbage mixture of hybrid napier+soybean was better than hybrid sorghum+soybean and setaria+soybean herbage mixtures in the nutrition of growing heifers. It had highest nutritive value, better digestibility co-efficients which showed better growth rate and higher feed efficiency. In ranking, hybrid napier+soybean herbage mixture was better followed by hybrid sorghum+soybean and setaria+soybean in nutritive value in the parameters studied. For future wasteland development program in humid-sub tropics of Himachal Pradesh hybrid napier and its intercropping with soybean is recommended for general adoption because of its better adaptability and higher nutritive value.