Mahmoud, B., El-Full, E. (2014). CROSSBREEDING COMPONENTS FOR DAILY GAIN AND GROWTH RATE TRAITS IN CROSSING OF RHODE ISLAND RED WITH GIMMIZAH CHICKENS. Egyptian Poultry Science Journal, 34(1), 151-163. doi: 10.21608/epsj.2014.5310
Bothaina Mahmoud; Ensaf El-Full. "CROSSBREEDING COMPONENTS FOR DAILY GAIN AND GROWTH RATE TRAITS IN CROSSING OF RHODE ISLAND RED WITH GIMMIZAH CHICKENS". Egyptian Poultry Science Journal, 34, 1, 2014, 151-163. doi: 10.21608/epsj.2014.5310
Mahmoud, B., El-Full, E. (2014). 'CROSSBREEDING COMPONENTS FOR DAILY GAIN AND GROWTH RATE TRAITS IN CROSSING OF RHODE ISLAND RED WITH GIMMIZAH CHICKENS', Egyptian Poultry Science Journal, 34(1), pp. 151-163. doi: 10.21608/epsj.2014.5310
Mahmoud, B., El-Full, E. CROSSBREEDING COMPONENTS FOR DAILY GAIN AND GROWTH RATE TRAITS IN CROSSING OF RHODE ISLAND RED WITH GIMMIZAH CHICKENS. Egyptian Poultry Science Journal, 2014; 34(1): 151-163. doi: 10.21608/epsj.2014.5310
CROSSBREEDING COMPONENTS FOR DAILY GAIN AND GROWTH RATE TRAITS IN CROSSING OF RHODE ISLAND RED WITH GIMMIZAH CHICKENS
A crossbreeding experiment was carried out between two genotypes of chicken namely Rhode Island Red (RIR) as standard foreign breed and Gimmizah (Gim) as a developed strain. Two crosses were made: ♂RIR x ♀Gim and its reciprocal cross (♂Gim x ♀RIR) to study crossing effects on variance components of the studied traits with an approach to potency ratio. The studied traits were: daily gain (DG) and growth rate (GR) during different periods: hatch (0 week)-4, 4-8, 8-12, 0-8 and 0-12 weeks of age for the combined sex and separately for each sex by genotype. Results showed there were significant differences for DG and GR for the combined sexes of both genotypes from 0 to 12 weeks of age . Gim had higher DG0-4, DG4-8, DG0-8 ,GR0-4 and GR0-8 than those of other genotypes. RIR had higher DG8-12 and DG0-12 and had faster GR during 4-8, 8-12 and 0-12 weeks of age than those of other genotypes. There were significant differences for DG and GR among males of genotypes from 0 to 12 weeks of age except DG0-8. There were significant differences for DG and GR among females of genotypes from 0 to 12 weeks of age, except DG0-4 and DG0-12. Estimates of direct additive effects for the combined sex were negative and highly significant for DG0-4, DG4-8, DG0-8 and GR8-12 being -0.54, -1.23, -0.47 and -4.50, respectively. Therefore, direct additive effects favoring Gim sires for previous traits. RIR had better performance than Gim sires for DG8-12, DG0-12 ,GR4-8 and GR0-12, because of the highly significant positive direct additive effects for these traits. Direct additive effects of both males and females were positive and highly significant for DG4-8 , DG8-12, GR8-12 and GR0-12. All estimates of maternal effects for the combined sexes were positive and highly significant for DG during all experimental periods , GR4-8 , GR8-12 and GR0-12. However, maternal effect estimates of both males and females were negative and significant for DG8-12, GR4-8 and GR8-12 .