IMPROVING THE PRODUCTIVITY OF BAHEIJ CHICKENS THROUGH BOTH OF BACKCROSSING AND SELECTION FOR BODY WEIGHT AT 8 WEEKS OF AGE C. GROWTH TRAITS, BODY CONFORMATION, CHICK VIABILIT, AND CARCASS TRAITS

Comparison study was carried out among three genotypes of Baheij breed, Baheij selected breed for increasing body weight at 8 weeks of age, Baheij upgraded groups through three generations and control group. Results were as follows:
1- Chicks of the 3rd generation were the heaviest (p<0.001) compared to those of the 1st and 2nd one at the different studied ages. Also, means of body weight of the upgraded group was the highest (p<0.001) compared to the other two groups and the selected group surpassed (p<0.001) the control one at all ages studied.
2- The three studied factors affected significantly growth rate percentage (GR %) where birds of the 3rd generation had the highest value of GR% through most of the studied intervals. The upgraded group had the highest mean at 12-16 wks of age where, the selected group grew faster at 8-12 wks of age. Both of the upgraded and the selected groups had significantly the highest values compared with the control one at 0-12, 12-20 and at 0-16 wks of age, while both of the upgraded and control groups surpassed (p<0.001) the selected one at 12-16 wks of age.
3- Body weight (BW), shank length (SL), keel length )KL) and breast width had significantly (p<0.01) higher averages at 12 wks. of age compared to those at 8 wks of age. Also, the selected group had significantly the highest BW while, the upgraded group had the highest average of SL. Moreover, males were heavier (p<0.01) than females. 4- The birds of the 2nd generation had the best (p<0.01) chick viability at 0-4 wks of age, while the values of both of the 1st and 3rd generations were nearly similar and higher than that of the 2nd one at 4-8 wks of age. 5- Live body weight, carcass, gizzard, and heart weights differed (p<0.01) in birds of the 3rd generation compared to that of the 2nd one at 16 and 20 wks of age. On the other hand, upgraded group had the highest (p<0.01) values of most of carcass studied traits compared to the others, while the control one had significantly (p<0.01) the heaviest liver. It could be concluded that upgrading through crossing Silver Montazah sires to Baheij strain dams surpassed the selection in Baheij strain at 8 weeks of age throughout three generations in improving growth traits, chick viability, and carcass traits of progeny of both F2 and F3.