الفهرس 
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Abstract
The inclusion of pubertal ewe lambs in the breeding flock is a mean of
increasing their lifetime productivity and hence, the profitability of sheep
farming. This particularly applies to ewe lambs in systems of intensified
productiun. Improving the reproduction of local ewe lambs was thought to be
the most important way to attain considerable increase in their lamb production.
One of the paths, which can be achieved for improving the production of local
sheep, is by starting their productive life as early as possible through early
puberty, mating, conception and lambing of ewe lambs.
Sexual development is affected by both genetic and environmental factors
and their interactions, Level of feeding seems to be the environmental factor
limiting to successfully exploiting the breeding potential of ewe lambs.
Although a high level of nutrition will advance puberty and even increase
ovulation rate in ewe lambs (Downing, 1980 and Hamra and Bryant, 1982), the
feeding of high-energy diets prior to breeding may be associated with an
increased incidence of barrenness in ewe lambs, possibly due to over fatness
(Stoerger et al., J976). So nutrition requirements ofloeal ewe lambs need to be
more precisely defined.
There is a wide interest of using Nigellasativa meal (NSM) as a source of
protein in ruminant diets in Egypt (Awadalla, 1997and Gabr et al., 1998). Gabr
(J 998) and El-Ayek (\999) concluded that NSM could be used as ingredients
ormulating diets for feeding sheep and can be replaced concentrate feed
ni,rure up to 50% on the basis of dietary crude protein level. Furthermore,
”SM showed beneficial effects on reproductive performance of males
(EI-Harairy el al., 2002 and Ali, 2003) and females (Youssef .r ai, 1998 and
EL-Ekhnawy el al. 1999) as well as on growth performance of/arm animals
(EL-Gohary, 1997 and El-Kady el ai., 2001), However, little information was
available on the effects ofNSM diets on puberty of farm animals especially on
ewe lambs.