Effect of dietary energy level on nutrient utilization, productive and reproductive performances of growing buffalo heifers [electronic resource].

Includes references.

Twenty four growing buffalo heifers were divided into three similar groups fed different dietary energy levels. The experimental rations were iso-nitrogenous with three levels of dietary energy. (80, 100 and 120 % TDN of the allowances) according to Kearl (1982). Heifers in the 151 group were fed 100% TDN (G1), while those in the 2nd (G2) and 3rd (G3) groups were fed 80 and 120% TON, respectively. Feeding experiment started from puberty age till the first 3 months of gestation. Ages and live body weights at the beginning of experiment were 529, 581, 516 days and 365, 356 and 371 kg for G1, G2 and G3, respectively). Heifers of G3 showed higher (P<0.05) total OM intake than the corresponding values of G1 and G2. Heifers in G3 showed the highest (P<0.05) digestibility coefficients of DM, OM, CP, EE and NFE and the lowest (P<0.01) digestibility coefficient of CF, however, the nutritive values were highly significant (p< 0.0 1) for TDN and DCP values. Heifers in G3 recorded the highest (P<0.05) average body weight, total gain and daily gain at conception and first 3 months of gestation, however, G2 showed the lowest (P<0.05) mean values. Feed conversion (kg DM/kg gain), was poorer in G2 and G3 than in Gl at conception and first 3 months of gestation. The differences were significant only between G1 and G2. Feed conversion as TON kg/kg gain was better (P<0.01) in G2 than in Gl and 03 at conception and first 3 months of gestation. Feed conversion as kg DCP/kg gain was better (P<0.05) in G3 than in G2, but did not differ significantly from that in G1. Heifers in G3 recorded the earliest (P<0.05) ages at puberty, in turn earliest ages at first service and conception. However, those in G2 showed the latest (P<0.05) ages. Interval from puberty to the first service or to conception was shorter (P<0.05) for heifers in G3 than in G2.

Summary in Arabic.

1