EFFECT OF FEEDING LEVEL AND REPLACEMENT OF NIGELLA SATIVA MEAL IN DITES OF RAHMANI EWE LAMBS ON: 1. GROWTH PERFORMANCE AT PRE-AND POST-PUBERTAL AGES.

SUMMARY
The influence of level of feeding (80 or 100% of NRC, 1985 allowance) and
substituting concentrate feed mixture (CFM) protein by Nigella sativa meal (NSM)
protein at the rate of 50% at the two tested levels on growth performance of ewe
lambs were studied .The roughage: concentrate ratio was 40:60. Forty Rahmani ewe
lambs were divided into four comparable groups according to live body weight
(LBW) and age. Ten ewe lambs in each group as follows: group1 (G1) received
80% of NRC (1985) allowance of crude protein (CP) based on LBW for early
weaned lambs up to 30 kg LBW, then, the allowances was changed for replacement
ewe lambs up to the end of the experiment. Group2 (G2), received as that in (G1),
but 50% of CFM protein was replaced by NSM protein. Group3 (G3), received
100% of NRC (1985) allowances Group4 (G4), received as that in (G3), but 50%
CFM protein was replaced by NSM protein. Daily oestrous observation was started
at 5 months of age to detect age and weight at puberty. Also, live body weight at
mating and conception were recorded. Results revealed that the LBW was
significantly (P<0.01) higher in ewe lambs fed 100% than those fed 80% CP by 7.4,
7.5 and 8.1% at puberty, mating and conception, respectively. LBW was
significantly (P<0.05) higher in lambs fed without than with NSM by 5.7 and 6.3%,
at the first and second level respectively .The LBW at puberty and conception was
the highest in ewe lambs fed 100% without NSM, while, those fed 80% with NSM
showed the lowest LBW. Ewe lambs that fed 100% with or without NSM showed
higher LBW at mating than those fed 80% with or without NSM. Average daily
gain (ADG) was significantly (P<0.01) higher in ewe lambs fed 100% than 80% CP
level by 12 and 37% through the intervals from 2 to 8 mo and from 8 mo to puberty
age, respectively. The ADG was significantly (P<0.05) lower in ewe lambs fed
diets with than without NSM, by 10.5% from 2-8 mo of age and insignificantly by
7.3% from 8 mo to puberty age. The ADG through the interval from 2-8 mo of age
was the highest in ewe lambs fed 100% CP without NSM, while those fed 80% CP
with NSM showed the lowest value. Digestibility coefficient of EE was
significantly (P<0.01) higher for lambs fed 100 than 80% CP level (67.35 vs.
64.29%). However, digestion coefficient of DM, OM, CP, CF and NFE did not
differ significantly between 100 and 80% CP level. Digestibility of DM, OM and
NFE significantly decreased in diets with than without NSM. The pronounced
decreased was observed in digestibility coefficient of DM (61.88 vs 68.12%) and
NFE (71.09 vs 78.55%) as compared to those in OM (66.50 vs 72.12%). Feed cost
per kg gain from 2 mo of age up to conception age was the lowest in ewe lambs fed
80% CP with NSM replacement and the most expensive cost was for ewe lambs fed
100% without NSM replacement.
It could be concluded that feeding Rahmani ewe lambs on diets containing
80% CP or diets with NSM had no deleterious effect on growth performance,
digestibility coefficients of nutrients and weight and age at puberty, mating and
conception. From the economical point of view, it could be recommended feeding
Rahmani ewe lambs on 80% CP level (from allowances of NRC,1985) with or
without 50% replacement of CFM by NSM protein.