Prediction of Body Weight and other Linear Body Measurement of Two Commercial Layer Strain Chickens

摘要

A total of 509 birds comprising 249 Nera Black (NB) and 260 Brown Shaver (BR) were used for this study. Data were collected on the birds from week one to twenty. Prediction of Body Weight (BW), Chest Girth (CG), Keel Length (KL), Body Length (BL) andShank Length (SL) were highly significant (p<0.001). The coefficient of determination (R2) varied from 85 to 99% for CG and KL. In both genotypes, the relationship between BW and other body measurements were higher in CG and KL traits and best describedby cubic model. Cubic function (R2 = 99%) predicted BW more accurately than quadratic and linear functions. The phenotypic correlation coefficients at day old m NB between BW and BL were positive, medium and highly significant (p<0.01), the phenotypic correlation coefficients for BW and BL in BR was low, negative and highly significant (p<0.01). Lower correlation values were obtained between BW and BL and significant (p<0.05) in NB strain at 4 weeks old. Also, negative highly significant was achieved between BW and SL. At 8 weeks old, low to medium correlation coefficients were observed between BW and SL, BW and KL, BW and CG in NB strain. Significant correlations were achieved between BW and SL, BW and CG traits in BR strain. At 12 weeks old, high, positive and significant (p<0.01) values were observed between BW and other traits in NB. The phenotypic correlation coefficients were of medium to high in NB between BW and KL, BW and BL at 16 weeks old. There were highly significant differences (p<0.01)between BW and other traits measured in BR strain. At 20 weeks old, the correlation values obtained were low to high in NB, lower values were also obtained for BR at the same age. As a result of these observations, it was considered possible to use the body weight in determining BL, SL, KL and CG.