Effect of different forms of complete diets on nutrient utilization in crossbred calves

Abstract

Experiments were conducted to study the effect of different forms of complete diets on rumen ecosystem vis-a-vis nutrient utilization in crossbred heifers. Fifteen crossbred female calves (aged around 8 months, average body weight 69.00± 4.20 kg) were randomly divided into 3 groups of 5 animals in each. All the animals were fed on the complete diets consisting of grass hay and concentrate mixture in the ratio of 60:40 on DM basis. In the concentrate mixture, 15 and 30% of the crude protein of the mustard-cake waS replaced with Leucaena learin T₂ and T₃, respectively. The diet of the control group contained grass hay and concentrate mixture in mash from whereas; T₂ and T₃ diet was offered in the form of block Among rumen metabolites, ammonia nitrogen was significantly (P<0.05) lower (27.58 mg/dl) in block fed ammals than the mash fed calves (35.38 mg/dl) due to proportionate intake of rotighage and collcentrate. Anaerobtc bacteria population was identical in 3 groups while anaerobic fungal population was almost double ih block fed calves as compared to the mash fed animals. The rumen protozoa represented higher values (27.62 x 106 /ml) in T₁ diet than either T₂(23 69 x 106 ml) or T₃ (23.80.x 106 /ml) diets. Dry matter intake (kg% body weight) was significantly (P<0.05) higher (3.08 vs 2.58) in block fed animals due to increase in nutient. density in block form diets. But this did not affect the digestibility coefficient of various nutrients among the treatment groups. As a result TDN intake was also higher from block form of diet as compared to the mash form of complete diets. Therefore. it was concluded that the complete  diets In the form of blocks enhanced the dry matter intake by 14 to 19 % in crossbeed heifers in spite of additions oe Leucaena leaves by replacing mustard-cake.