SUMMARY
The present study was undertaken to investigate the feasibility of establishing a genetic
improvement program for meat production in Barki sheep as a result of selection for weaning
weight. The present study utilized an original body weight data collected from the Barki sheep
flock raised in the north-western coast of Egypt that belongs to the Desert Research Centre from
1963 to 2005. A total of 1046 animals (542 females and 504 males) progenies of 163 sires and 557
dams were included in the analyses.
The Monte Carlo simulation technique was utilized to construct a three-stratum nucleus
breeding scheme consisting of a nucleus flock linked with five multiplier flocks which were
consequently linked with commercial flocks of the producers. Such structure was replicated three
times for higher accuracy. Moreover, mating was simulated for two successive seasons in the
multiplier and commercial flocks and for three successive seasons in the nucleus flock. Two
scenarios were simulated whereas the improvement occur without (scenario-1) and with (scenario-
2) dissemination of sires from the nucleus flock.
Results indicated that weaning weight breeding values of sires, dams and offspring as well as
average weaning weight in the nucleus flocks were generally exceeding those corresponding values
in the multiplier and commercial flocks. Breeding values as well as average weaning weight tended
to increase as season advanced and being higher in scenario-2 than in scenario-1. Producers of the
multiplier and commercial flocks would accomplish higher breeding values as well as average
weaning weight in the first season as soon as they shift from scenario-1 to scenario-2. The present
study showed that it is technically feasible to implement nucleus breeding schemes in providing
improved sires with higher weaning weight breeding values for the genetic improvement of meat
production in Barki sheep.