Effect of Frequent Turning on Hatchability and Distribution of Embryo Mortality

FACTORS affecting hatchability may be divided into those which are concerned with the breeding of the parent stock, the nutrition of the parent stock, and the environmental and mechanical factors which are involved in the care and the incubation of the eggs. This paper is concerned with the study of one mechanical factor, namely, the effect of the number of times that the eggs are turned, on the distribution of embryo mortality and on hatchability. The earliest work on the distribution of embryo mortality was that of Payne (1919) on the domestic fowl. He found that there are two distinct periods of high mortality, the first on the fourth day and the second on the nineteenth day of incubation. He noted that 65 percent of all embryo mortality was found on or near these peaks; that is, on the 4th, 5th, 6th and 18th, 19th and 20th days. Data reported . . .