Two-generations of crossbreeding experiment involving Baladi Saudi (S) and White Leghorn (L) chickens were evaluated for age at first egg (AFE), first three-month egg production (EP3) and annual egg production (AEP). Six genetic groups of LxL, SxS, LxS, SxL, LxSL and SxLS were produced in this experiment (two pures, two F1 crosses and two backcrosses). Variance components and heritabilities for these egg traits were estimated using DFREML procedure of multi-trait animal model. The genetic model of Dickerson was used to estimate the genetic components of this experiment in terms of direct (GI) and maternal (GM) additive effects, direct (HI) and maternal (HM) heterosis, and direct recombination loss (RI). Backcross of Lx¾L¼S recorded higher egg production than other crossbred groups. Heritabilities for AFE, EP3 and AEP were 0.55, 0.31 and 0.54, respectively. Direct additive effects (GI) for AFE, EP3 and AEP were considerable and in favour of the L breed. L-sired hens had high GI compared to the S-sired hens for the traits. For maternal additive effects (GM), a reversible trend was recorded in favour of S breed. Crossbred hens recorded positive estimate of HI for AEP and negative estimate for AFE. The estimates of HI were -2.7 % for AFE and 2.7% for AEP. Estimates of HM in daughters of crossbred dams for EP3 and AEP were positive, while the estimate for AFE was negative and favourable. The estimates of HM were -16.4% for AFE, 19.1% for EP3 and 12.3% for AEP. Estimates of RI in crossbred hens for AFE, EP3 and AEP were 1.6 days, -11.9 egg and -28.3 egg, respectively; RI for age at first egg was limited, while the two estimates for egg production were high.
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