Influence of ruminally protected fat and urea treated corncobs ensiled with or without corn steep liquor on nutrient intake, digestibility, milk yield and its composition in Nili-Ravi buffaloes

Sixteen early lactating Nili-Ravi buffaloes, four animals in each group, were used in a Completely Randomized Design to evaluate the effect of varying levels of both ruminally protected fat and urea treated corncobs ensiled with or without corn steep liquor (CSL) on feed intake, digestibility and milk production and its composition. Four experimental diets were formulated. The control (C) diet was balanced to contain 0% fat and 35% urea treated corncobs ensiled with 0% CSL. The low fat (LF), medium fat (MF) and high fat (HF) diets had 45, 55 and 65% urea treated corncobs ensiled with 9% CSL and 2, 4 and 6% ruminally protected fat, respectively. Dry matter, crude protein (CP) and neutral detergent fiber (NDF) intakes by buffaloes remained similar across all treatments. However, DM and NDF as a percent of body weight and digestible DM intakes were higher in HF diet when compared to C, LF and MF diets. Digestible NDF intakes were also significantly higher in HF diet as compared to all other diets. The intakes of ADF and digestible ADF were higher in MF and HF than C and LF diets. The significant variation in digestible DM, ADF and NDF intakes may be attributed to the ammoniation of corncobs along with CSL that caused significant changes in the degradability and digestibility of the diets. Ether extract and digestible EE intakes differed significantly (p<0.05) among all treatments. Intakes of EE were the highest in animals fed HF diet, which was because of added fat. Apparent DM digestibility was the highest in animals C diet and was the lowest in those fed LF diet. Neutral detergent fiber and ADF digestibilities were higher in animals fed diets containing urea treated corncobs ensiled with 9% CSL when compared to those fed diets containing urea treated corncobs ensiled without CSL. Apparent digestibility of CP was noted highest (71.47%) in animals fed HF diet when compared to those fed MF (67.75%), LF (67.04%) and C (65.39%) diets. Milk yield (4% FCM) was the higher in buffaloes fed HF, MF and LF diets than those fed C diet. These results indicated that increasing levels both of fat and urea treated corncobs ensiled with CSL elevated the negative effects of poor quality fibrous feed on milk production by buffaloes.