Effects of short heating periods during egg storage on quail embryonic development, incubation performance, chick quality, and chick performance up to 35 days

This study investigated the effects of pre-heating fertile Japanese quail eggs during storage on embryonic development, incubation performance, hatched chick quality, and chick performance up to 35 days of age. The experiment was laid out in a completely randomized design in a 3 × 2 + 1 factorial arrangement, totaling seven treatments. These treatments included three storage periods (3.5, 6.5, and 9.5 days) and two pre-heating periods (0 and 4 h at 37.5°C and 60% RH). Pre-heating was conducted on the third day of egg storage inside the incubator machine, with the control treatment involving the storage of fertile eggs for 12 h without pre-heating. Extended egg storage for more than six days led to an increase in the percentages of yolk and shell, elevated albumen pH, reduced albumen percentage, diminished hatchability rate, and an increased embryonic mortality rate. Pre-heating the eggs resulted in a reduction in the weight, length, and amount of residual yolk sac of the newly hatched chick. No significant effects of pre-heating fertile Japanese quail eggs during storage were observed on the studied variables. Therefore, the protocol involving a 4-h pre-heating at 37.5 ºC and 60% relative humidity during the storage period does not yield improvements in incubation rates or chick quality in Japanese quail. Further studies are warranted to determine the optimal protocol for pre-heating Japanese quail eggs.