Comparative Staging of Blastoderm Development at Oviposition in Eggs from Layer and Broiler Grandparent Breeder Flocks

Abstract

Recent decades were characterized by genetic selection of broiler and layer chickens for enhanced growth rate and meat yield or intensified egg production, respectively. It is to be expected that genetic selection for various traits would also influence embryo development. The effects of different strains of chickens on egg weight, stage of blastoderm, variation of the blastoderm development and Pearson correlation between egg weight and stage of blastoderm at oviposition were studied in the current study. Hatching eggs were randomly collected from three layer chicken lines (Layer-1, Layer-2, and Layer-3) raised in Poultry Research Institute, and two broiler grandparent flocks (Female and Male) from Aviagen Anadolu. The age of all chicken lines was 36 week. A total of 30 eggs in each line were used, and egg weight and the blastoderm development of the embryos were determined at oviposition time. At the end of the research, significant difference in egg weights (P<0.05) were observed for all lines except between Layer-1 and Layer-2, between Layer-2 and Female grandparent line (P>0.05). The mean stage of blastoderm development in male grandparent line eggs significantly lower than other four genetic lines (P<0.05). Moreover, the coefficient of variance (CV) of blastoderm developments was 4.30, 3.42, 3.60, 6.27, and 11.33 for Layer-1, Layer-2, Layer-3, Female, and Male grandparent lines, respectively (P<0.05). However, there was no significant correlation between egg weight and stage of blastoderm development for all flocks (P>0.05). It can be concluded that genetic selection affects not only production traits but also developmental pattern of the embryos in the oviduct. Hence, it may be beneficial to adjust storage condition according to the line being used.