The buffalo is an important animal in the agriculture economy of our country and the most useful animal for many millions of poor people, especially those living in Asia.

So far, no definite studies with regard to the nutritional requirements of the buffalo at various stages of growth and production (meat and milk) have been conducted. The feeding of buffalo in the sub-continent is based on various cereals and cash crops and are generally subjected to various nutritional imbalances, as a result, the genetic potential with regard to growth and production (meat and milk) of buffalo is not fully exploited.

Thus there is a desperate need for determining the specific feeding requirements of the indigenous dairy buffalo. For the purpose digestibility and metabolic studies for various nutritional needs for growth, fattening and production are to be conducted. Thus the present study was designed to study the effect of different plans of nutrition on growth, efficiency of feed utilization and nutrients digestibility in Nili-Ravi buffalo male calves.

Twenty-seven buffalo male calves of 9-12 months of age were randomly divided into nine groups. Three different levels of protein and metabolizable energy (80, 100 and 120% of NRC, 1976 Standards for beef cattle) were incorporated in the nine experimental rations.

After the trial of 140 days, the buffalo male calves gained weight 102.67, 110.64, 90.33, 36.00, 73.33, 127,34, 98.67, 82.34 and 110.34 Kgs. in groups 1-9, respectively. Maximum growth was recorded in group 6 [CP 100% and ME 120% of NRC (1976) Standards for beef cattle). Weight gain was non-significant due to varying levels of protein in the rations while weight gain was significant (P<0.05) due to varying levels of energy in the rations. Maximum growth rate of 909 gms. per day in group 6 (CP 100% and ME 120%) was recorded. The regression equation for weight gain with the relation to protein and energy intake was as follows: Weight gain (WG) = -297.28 + .425 (Pr) ± 63.67 (En)

The feed consumption decreased with the increase of protein level in the rations while feed consumption increased with the increase of ME level in the ration but the effect was statistically non-significant.

Maximum feed was consumed in group 6 (CP 100% and ME 120%). It was observed from the study that dietary protein had significant effect on feed efficiency and it was improved with the increase of dietary protein in the ration. Feed efficiency also improved significantly with the increase of energy in the rations. It was noted from the study that the dry matter intake reduced with the increase of dietary protein but dry matter intake increased with the increase of ME level in the ration. The effect was statistically non-significant. Protein intake was significantly increased with increase of protein level while ME level in the ration had non-significant effect. ME intake was non-significant with the increase of protein level but it was significantly increased with the increase of ME level in the ration.

The digestibility of crude protein and ether extract increased with the increase of protein and energy level in the rations but the differences were nonsignificant. The digestibility of dry matter was increased at varying levels of protein and energy but the differences were significant (P<0.0l). The digestibility of NFE and crude fibre were also increased at varying levels of energy significantly (P<0.01) but these were low at 100% protein level than 80 and 120% protein level. It was observed that the digestibility of all the nutrients increased at high plan of nutrition (protein and energy).

It was concluded that protein requirements of buffalo male calves were the same as recommended for beef cattle NRC (1976) but metabolizable energy requirements were 20% higher than the recommended level for beef cattle, NRC (1976)