ABSTRACT The objective of this study was to determine the effects of egg quality characteristics (egg weight, egg width, egg height, and shape index) on fertility of eggs of Japanese quail with different colored feathers (yellow, white, grizzled, and normal), which are of economic importance for poultry production. For this purpose, 383 eggs of Japanese quail with various feather colors were used. In the study, usability of classification and regression tree (CART) data-mining algorithm as a classification tree method is necessary for poultry breeders to define proper cut-off values of egg quality characteristics that ensure Japanese quail eggs at good quality in fertility. Fertility as the dependent variable in the study was examined as a binary trait (fertile and infertile) and all the egg quality traits accepted as explanatory variables were continuous variables. Feather color was also included as a nominal categorical explanatory variable. The classification tree results showed that the highest fertility ratio of 90.9% was obtained from the eggs of Japanese quail of white, grizzled, and normal feather colors with 10.425 g ≥ egg weight, 24.565 mm ≥ egg width, or the fertility ratio of 88.2% of the eggs was observed with 10.425 g ≤ egg weight and 25.605 mm ≥ egg width. Consequently, usability of the tree-based CART algorithm is important in practice for properly establishing fertilized eggs, depending on feather color types of Japanese quail.

ABSTRACT The objective of this investigation was to determine the differences between normal and PSE (pale, soft, exudative) turkey breast meat in terms of chemical composition, pH, color, myoglobin, and drip loss. Pale and normal skinless, boneless turkey breast fillets were taken from a poultry slaughterhouse in Van/Turkey at about 2-3 h postmortem. Spectrocolorimetry (CIE L*a*b*), pH, protein, ash, dry matter, lipid, myoglobin, and drip loss were measured in normal and pale color turkey breast muscle. The normal breast meat had significantly lower L*, a*, and b* values in comparison with the pale breast meat. Myoglobin concentration and pH were significantly higher in the normal breast meat compared with that of the pale breast meat. Protein content was found to be significantly lower for the pale group compared with the normal group. No significant difference was found in ash, dry matter, and total lipid content between normal and pale breast meat. Drip loss was significantly affected by breast meat color groups at days 1, 2, 3, and 4 postmortem. Pale, soft, exudative turkey breast meat can lead to differences in the chemical composition and shelf life of the product.