PREDICTON OF PERFORMANCE BASED ON DIFFERENT ECONOMIC TRAITS IN DANDARAWI AND GOLDEN MONTAZAH PULLETS.

Document Type : Research articles.

Authors

Department of Poultry Production, Fac. of Agric., Cairo Univ., Fayoum Branch.

Abstract

Different prediction equations were established for egg production
(EN
90), 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. EN
90 is a function of either EW90 or EM90 (Dand). EW90 is a
function of each of keel length at 8 weeks of age (KL
8,Dand) and KL12
in GM. SG is a function of ST for both breeds. More EN90 can be
predicted through lighter body weight (BW
8) and longer shank length
(SL
8) at eight weeks of age, however, heavier BW8 and shorter SL8 at
eight weeks of age can be used as predictors for higher EM
90 for Dand
pullets. Heavier body weight at sexual maturity (BW
SM) and longer
KL
12 resulted in retardation of sexual maturation for Dand. The only
significant positive factor resulting in 14.5% of the variability in EW
90
was BW12 for GM. Heavier BW8 was associated with decreasing EN90
in Dand. Each of EN90, EW90 and BW8 were significantly increased
EM
90 for Dand, whereas SL8 negatively associated with its EM90. For
GM, EN
90 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 Ytrait were actual and prediction for future economic production will be
reliable .


Keywords