Hatching Characteristics and Growth Performance of Eggs with Different Egg Shapes

ABSTRACT

This study was carried out to identify the effect of the egg shape index on the hatchability, performance, and carcass yield of Japanese quails (Coturnix coturnix Japonica ). Eggs were incubated in three groups, according to three different egg shape index (SI) values (Group SI-I 70.00-73.85%, Group SI-II 73.86-77.71% and Group SI-III 77.72-81.57%). Unhatched eggs weight loss (HEWL) was correlated with the egg shape index groups (SI-I 18.51%, SI-II 13.34% and SI-III 13.96%; p 0.01), but not with the initial unhatched egg weight (HIEW), hatched egg weight (HEW), or eggshell weight of unhatched eggs (HSW) (p>0.05). The live weight of female and male chicks hatched from SI-I, SI-II, and SI-III egg shape index groups were compared at weeks 4 (female/male 249.12/237.77, 244.69/236.35, and 241.52/229.72 g, respectively) and 5 (female/male304.89/272.42, 295.76/274.34, and 285.42/271.29 g, respectively), and the results showed that females were heavier than males (p 0.05; p 0.01; p 0.001, respectively).The effect of egg shape index on slaughter weight (p 0.05), left leg weight (p 0.05), liver weight (p 0.01) and liver rate (p 0.01) was significant. Females were heavier at slaughter than males in the egg shape index groups SI-I (p 0.05), SI-II (p 0.05), and SI-III (p>0.05) (female/male 296.87/283.80, 287.95/278.00 and 283.86/278.10 g, respectively). Males presented higher carcass yield in SI-I (p>0.05), SI-II (p 0.01) and SI-III (p 0.05) (female/male 74.40/75.92, 74.50/76.44 and 74.80/76.42%) groups than females. Egg shape index had no effect on initial egg weight (IEW), shell blunt end weight (SBW), chick weight, shank length, growth performance or carcass traits, but egg shape indexwas correlated with egg length, egg width, and hatchability of fertile eggs (p 0.05).(AU)