Predicton of performance based on different economic traits in dandarawi and golden montazah pullets

الملخص EN

Different prediction equations were established for egg production (EN90), egg weight (EW90), egg mass (EM90) in the first 90 days of production, sexual maturity, specific gravity (SG), shell thickness (ST) and shape index (SI) of egg based on the coefficient values of selected variables under each.

Data from Dandarawi (Dand) and Golden Montazah (GM) were used.

The R-square values of each equation were calculated.

EN90 is a function of either EW90 or EM90 (Dand).

EW90 is a function of each of keel length at 8 weeks of age (KL8, Dand) and KL12 in GM.

SG is a function of ST for both breeds.

More EN90 can be predicted through lighter body weight (BW8) and longer shank length (SL8) at eight weeks of age, however, heavier BW8 and shorter SL8 at eight weeks of age can be used as predictors for higher EM90 for Dand pullets.

Heavier body weight at sexual maturity (BWSM) and longer KL12 resulted in retardation of sexual maturation for Dand.

The only significant positive factor resulting in 14.5% of the variability in EW90 was BW12 for GM.

Heavier BW8 was associated with decreasing EN90 in Dand.

Each of EN90, EW90 and BW8 were significantly increased EM90 for Dand, whereas SL8 negatively associated with its EM90.

For GM, EN90 and EW90 significantly increased EM90.

In general, equations used for predicting economic traits that had highly significant R-square indicating that variables associated with each Y- trait were actual and prediction for future economic production will be reliable.