Ali,, U. (2008). MULTIPLE REGRESSION ANALYSIS OF EGGSHELL MEASUREMENTS IN TWO GENETIC GROUPS OF CHICKEN. Journal of Animal and Poultry Production, 33(3), 1875-1881. doi: 10.21608/jappmu.2008.217767
U. M. Ali,. "MULTIPLE REGRESSION ANALYSIS OF EGGSHELL MEASUREMENTS IN TWO GENETIC GROUPS OF CHICKEN". Journal of Animal and Poultry Production, 33, 3, 2008, 1875-1881. doi: 10.21608/jappmu.2008.217767
Ali,, U. (2008). 'MULTIPLE REGRESSION ANALYSIS OF EGGSHELL MEASUREMENTS IN TWO GENETIC GROUPS OF CHICKEN', Journal of Animal and Poultry Production, 33(3), pp. 1875-1881. doi: 10.21608/jappmu.2008.217767
Ali,, U. MULTIPLE REGRESSION ANALYSIS OF EGGSHELL MEASUREMENTS IN TWO GENETIC GROUPS OF CHICKEN. Journal of Animal and Poultry Production, 2008; 33(3): 1875-1881. doi: 10.21608/jappmu.2008.217767
MULTIPLE REGRESSION ANALYSIS OF EGGSHELL MEASUREMENTS IN TWO GENETIC GROUPS OF CHICKEN
Poultry Production Department, Faculty of Agriculture, Ain Shams University, Cairo, Egypt
Abstract
The research was conducted on eggs of 148 heterozygous naked neck (Nana) and 124 normally feathered (nana) genotype chickens maintained in individually cages. Three hundred eggs selected randomly (150 each). Egg weights (g), egg length (mm), egg width (mm), eggshell weight (g), eggshell thickness (mm) and deformation were measured. The present results revealed that birds having Na inheritance had superior eggshell quality compared to nana genotype. Shape index was negatively correlated with eggshell deformation in both genotypes. However, there was significantly negative relationship between shape index and shell thickness in nana genotype. The eggshell percentage was significantly positive correlated with shape index in Nana genotype. Opposite trend was noticed in nana ones. Eggshell deformation was significantly negative correlated with shell thickness, shell percentage and weight 1 Cm2 shell in both genetic groups. The following equations were developed to predict shell thickness:
Y= 0.225EW-0.109SI+4.43SP-150WCM+3.29 (R2=0.63) (Nana genotype),
Y= 0.072EW-0.076SI+1.373SP+245WCM+7.84 (R2=0.78) (nana genotype).
Where, EW = egg weight, SI= shape index, SP = shell percentage and WCM = weight of 1cm2 shell.
In conclusion, it can be concluded that incorporation of Na gene in laying hens improve eggshell quality. Also, prediction equations can be developed to get information about eggshell traits.