Aim: This study aimed to contribute to the productivity improvement of the local chickens by enhancing their egg production traits using a crossbreeding program between Alexandria (local strain) and Lohmann White (commercial strain). Materials and Methods: One thousand two-hundred and eighty-five 4-week-old chicks from two strains: Alexandria local strain (AA) and Lohmann White commercial strain (LL) and their reciprocal crosses obtained from 16 males and 160 females, were used to produce four genetic groups (AA, LL, AL, and LA). Differences among genotypes, direct additive, heterosis, and reciprocal effects were investigated regarding the following traits: Body weight at 4 and 8 weeks and at the age of sexual maturity, age at sexual maturity, egg production, average egg weight, and egg mass during the first 90 days of laying. Results: Statistically significant effects of the genotypes were observed on traits studied. Analysis of direct additive effects showed that AA was superior as a sire strain for improving body weight at early age. For egg traits (age at sexual maturity, egg production, average egg weight, and egg mass), LL was better as a sire strain to improve these traits. Significant positive heterosis percentages were observed for body weight. The crosses (AL and reciprocal) were significantly superior in egg traits (egg production, average egg weight, and egg mass) compared to the local strain. The cross (LA) laid significantly earlier than the local strain. Analysis of reciprocal effects cleared that the local strain could be used as a strain of dam to improve body weight and egg traits. Conclusion: Crossing improved egg production, egg weight, and egg mass in hybrids compared to the local strain.

Aim:This research was conducted to determine the most affecting parameters on hatchability of indigenous and improved local chickens’ eggs.Materials and Methods:Five parameters were studied (fertility, early and late embryonic mortalities, shape index, egg weight, and egg weight loss) on four strains, namely Fayoumi, Alexandria, Matrouh, and Montazah. Multiple linear regression was performed on the studied parameters to determine the most influencing one on hatchability.Results:The results showed significant differences in commercial and scientific hatchability among strains. Alexandria strain has the highest significant commercial hatchability (80.70%). Regarding the studied strains, highly significant differences in hatching chick weight among strains were observed. Using multiple linear regression analysis, fertility made the greatest percent contribution (71.31%) to hatchability, and the lowest percent contributions were made by shape index and egg weight loss.Conclusion:A prediction of hatchability using multiple regression analysis could be a good tool to improve hatchability percentage in chickens.

Genetic evaluation of growth and litter traits was carried out in a line of rabbits selected for litter size at weaning. The evaluation was performed on 483 does and 10847 offspring over six consecutive years of production from 2005 to 2011, using BLUP under an animal repeatability model. The high proportions of animals with positive transmitting ability estimates for slaughter weight makes this trait much better to select for than weaning weight or daily weight gain, if we are looking for growth improvement. Whereas, for litter traits studied, Litter size at weaning seems to be the best trait to use as a selection criteria for improving the reproductive performance rather than Litter size at birth or Number born alive. Estimates of rank correlations were low between weaning weight and both of slaughter weight & daily weight gain While, correlation among ranks of transmitting ability value between slaughter weight and daily weight gain was moderate. Genetic trends estimated as a regression coefficient of trait breeding values on year of birth, which present generation number, for growth and litter traits were about 9 and 58 g/ year for weaning weight and slaughter weight, respectively. Whereas, for daily weight gain during the fattening period, the genetic trend increased yearly by 1.08 g/ d. The value of genetic trend for litter size at weaning, which used as criteria of selection in this line, means that, we can get one kit more from each litter each 12 generations.

The study aims to evaluate genetically milk production of a synthetic maternal line of rabbits (V line) and semen quality of bucks. A total of 77, 70 and 70 does were used to estimate milk yield from kindling up to weaning for more than 4 parities. Twenty males of rabbits at 63 days of age were selected random and blood samples were collected to determine serum follicle-stimulating (FSH), luteinizing (LH) and testosterone hormones at the ages of 63 days and 5 and 6 months. Milk yield were 113.06, 172.87 and 211.76 g at 7 th , 14 th and 21 st days of age after parturition, respectively. It is noticeable that the effect of the month had no significant effect on milk yield at 7 th and 21 th days of lactation period, while it was affected significantly at 14 th days, and the month of December was the highest rate of milk yield in the months of the productive year. The effect of parity number more than 4 th on milk yield was increased significantly with the advancement and decreased for other parities. The correlations between FSH, LH and testosterone hormonal levels and rabbits sperm concentration and advance sperm motility were significantly affect at 63 days. But, the correlation between FSH and LH levels and semen volume and total sperm out percentages were significant at 63 days. It was concluded that the semen quality was associated with an increase in testosterone concentrations at 5 and 6 months. In summary, it can be observed that the evaluation of the V line rabbit as a maternal line with high milk yield during the lactation period and that high semen quality for males V line rabbits can be predicted by high levels of hormones LH, FSH and testosterone concentrations at 63 days of age.