Effect of Storage Period and Egg Weight on Embryo Development and Incubation Results

A total number of 300 females and 30 males of two experimental broiler lines, TT (male) and PP (female), with 39 and 36 weeks of age, respectively. Experiment 1 (TT) evaluated the effect of storage time (ST) on hatchability and embryo mortality (EM). Eggs were stored for 2 (ST1), 4 (ST2), 6 (ST3), 8 (ST4), 10 (ST5), 12 (ST6), and 24 (ST7) days and EM was assessed in the periods of 0 to 6 (EM 1), 7 a 13 (EM2), 14 to 17 (EM3), 18 to 21 (EM4), and 0 to 21 (TEM) days. Experiment 2 (PP) evaluated the effect of egg weight (EW) on embryo development. Eggs were individually collected and weighed. Embryos were collected and weighed on days 9 (EW9), 11 (EW11), 13 (EW13), EW15, 17 (EW17) days of incubation and at hatching (EW21). ST linearly influenced hatchability and EM, with an estimated 1.17% reduction and a 1.15% increase, respectively for each 1.0 day of storage. Hatchability was reduced in 21% between ST2 and ST7, resulting from a 462% increase in EM. The correlation between egg weight and embryo weight (EW) was significant after EW3 (0.25), reaching 0.72 for EW21, which corresponded to 70.92% of egg weight. The estimated increase in embryo weight for each 1.0g increase in egg weight was 0.71g for EW21.