EFFECT OF MAIZE (<i>ZEA MAYS</i>) COB BASED TOTAL MIXED RATION IN GROWING CALVES

The present study was conducted to study the effect of maize (Zea mays) cob on replacing paddy straw in the Total Mixed Ration (TMR). Twelve cross bred calves of about 5 to 8 months of age with body weight ranging from 41 to 79 kg were divided into two groups of six each in completely randomized design. Five complete diets were prepared (TMR1 to TMR5) using maize cobs at the level of 0%, 25%, 50%, 75% and 100% replacement of paddy straw in the diets containing 12 % CP and 60 % TDN of 50:50 concentrate to roughage ratio. There was significant (P<0.01) differences among the diets in OM, CF, NFE, TA, AIA, NDF, ADF, Lignin, Hemicellulose and Cellulose contents. In vitro rumen fermentation study showed significantly (P<0.01) higher total gas (ml/200 mg/48 h), in vitro dry matter and organic matter degradability in maize cob based ration than paddy straw contained ration (51.17 vs 36.00; 62.87 vs 57.25; 64.80 vs 59.93). Paddy straw (100%) based diet as control ration and maize cob (100 % replacement of paddy straw) based diet as treatment ration fed to growing calves for sixty days in growth trial. A seven day digestion trial was conducted in the middle of the experiment. The digestibility (%) of DM, OM, CP, EE, CF and NFE were significantly (P<0.01) higher in the maize cob based diet fed group than paddy straw based diet fed group. The average body weight gain (kg) and FCR (kg DMI/ kg gain) were significantly (P<0.05) higher in maize cob fed animals (19.47; 6.10) than paddy straw fed animals (16.02; 7.34). The feed cost per unit of weight gain in calves fed paddy straw based diet was numerically higher (30.78 %) than calves fed on maize cob based ration. It could be concluded that maize cob based ration could replace paddy straw at 100 % level in total mixed ration without affecting feed intake and nutrient digestibility and may also improve the body weight gain and reduce feed cost in growing calves.