Effect of egg size on hatchability of Japanese quail (Coturnix coturnix japonica) chicks

Egg size remains one of the major factors that qualify eggs for successful hatchability. Ninety (90) Quail eggs were labelled, weighed and sorted into small (8.91g averagely), medium (9.80g averagely) and large (10.76g averagely) with thirty eggs per size. The eggs were incubated at 99.7°F and 83.5%RH in the setter with 98.5°Fand 85%RH in the Hatcher. Final egg weights were noted prior to transfer into the Hatcher. The unhatched eggs were opened to determine causes of embryonic mortality based on developmental stage at which the death occurred. Data collected were subjected to one-way analysis of variance. The egg weight losses in gram and percentage were not significantly (P>0.05) different across all egg sizes. Hatchability of 31.25%, 47.32% and 45.00%, embryonic mortality of 68.75, 52.68% and 55.00%, Dead in germ of 50.00%, 40.18% and 45.00%, Dead in shell of 18.75%, 12.5% and 10.00%, hatching weights of 5.74g, 6.15g and 7.15g respectively for small medium and large eggs. It was concluded that egg size does not influence weight loss rather it influences fertility and hatchability. The medium sized eggs are recommended when higher hatchability is desired in hatchery operation while the large eggs are preferred when higher chicks' weights are desired.