TY - SER AU - Zaky,H.I. TI - Genetic and crossing effects in the crossing between sinai and white leghorn chickens for egg production traits KW - Eggs KW - Production KW - Quality KW - Chickens KW - Genetics KW - Heterosis KW - Crossing over (Genetics) N1 - Includes references N2 - The Sinai fowl (S), White Leghorn breeds (WL) and their reciprocal crossbreds (SxWL) and (WLxS) were used to evaluate the effects of crossing on egg production and estimates the heterosis, additive, maternal, sex-linked and reciprocal effects during the first three months of production. Egg number (EN), egg weight (EW), egg,production (EP), age at first egg (AFE), body weight at sexual maturity (BWM) and egg quality traits were evaluated under desert conditions. Significant differences (P<0.05) were found between genetic groups for EN, EW, EP and BWM. The Sinai females matured earlier but produced less egg than WL females. White Leghorn showed higher EN and EP and reached later at sexual maturity when compared to Sinai and the crossbreds. Significant differences between the crossebreds were found for all production traits. Hybrid (WLxS) females commenced lay at an earlier age and produced more eggs than crossbred (SxWL) females UR - http://nile.enal.sci.eg/EALE/2007/EJDR/5707/1/193.pdf ER -