ABSTRACT
The study included two experiments to compare efficiency of using basic and untraditional
energy sources on productive and reproductive performance of ewes and growth rate of lambs. At
first experiment, twenty-four Rahmani ewes aged 3.0- 3.5 years and weighed 46.19±8.56 kg were
divided into two similar groups (N=12 each). The 1st group (L) received 4021 kcal/kg/DM while
the second (L1) received 4469 kcal/kg/DM Both treatments started 28 days prior-breeding season
until weaning the lambs. In this experiment, live body weight (LBW) of ewes was measured during
different stages of gestation. At postnatal, eight ewes and their lambs were chosen (N=4 in each
energy level) to determine their LBW, suckling milk (quantity and quality) and some udder
measurements. At second experiment, fourteen male Rahmani lambs (average body weight 22.72
kg at 14 weeks of age) were divided into two groups, 7 lambs / energy level (L1 and L2), to record
growth rate and their blood parameters. Results in 1st experiment indicated that, LBW of ewes was
significantly (P<0.05) higher with L2 than L1 at days 96 to 140 of pregnancy. The calculated
reproductive parameters as pregnancy rate and litter size of ewes fed L2 were significantly
(P<0.05) higher (100.00% and 1.92 %) than ewes fed L1 (83.33% and 1.40%), respectively. Ewes
and their lambs in L2 group achieved booster (P<0.05) values in LBW, suckling milk (amount and
composition) and udder measurements than that of L1group. However, in 2nd experiment it shown
that male lambs fed L2 had lower feed intake, higher daily gain, better feed conversion and
economical efficiency. Serum glucose and cholesterol of male lambs in L2 were significantly
(P<0.05) higher than L1 lambs while, urea level of L1 lambs was significantly higher (P<0.05)
compared to L2 lambs. Other serum parameters as total protein and triglyceride were slightly
higher in the blood of L2 lambs compared to L1 lambs. Generally, it could recommend to use
protected fat (PF) and corn steep liquor (CSL)as energy supplement for improvement of productive
and reproductive performance of ewes and their suckling offspring, growth rate of lambs and their
blood metabolites.