Identification of critical periods for turning broiler hatching eggs

摘要

Optimum turning of eggs during incubation has been of interest almost since the first obaservations of the incubational habits of feral fowl. Considerable research has been directed at determination of the times during incubation when turning eggs was most critical to obtain maximum hatchability. In an early study, Card (1926) maintained that eggs turned solely during the first six days of incubation hatched almost as well as eggs turned throughout incubation.