Pre-Incubation Warming and Hatchability of Chicken Eggs

THE hatchability of turkey and chicken eggs usually increases when the eggs are subjected to certain pre-incubation warming treatments. Kosin (1956) reviewed the relevant literature and also obtained evidence in a series of experiments with chicken and turkey eggs indicating that warming procedures generally improved the hatchability of fertile eggs. He found that a single five hour warming period at 99 3/4°F. was effective with turkey eggs. Subsequently Kosin (1957) observed that placing eggs in a 72–74°F. environment overnight also improved the hatchability of turkey eggs. Because these two treatments were not tested with chicken eggs, it seemed desirable to observe the effect of these warming treatments upon the hatchability of chicken eggs. METHODS Four trials were conducted as follows: 1. For the first trial eggs were saved for a 22-day period from a flock mating of White Rock ♀ ♀ × Synthetic Dominant White ♂ ♂ and the . . .