Variation in Fertility of Inbred Chickens and of Fertility and Hatchability in White Holland Turkeys

WHILE differences in fertility between breeds and strains of chickens and between families of turkeys have been suspected, it has been difficult to establish the significance of such differences. Under conditions of natural mating, social, mechanical and other environmental factors may mask the fertilizing ability of a male’s semen and/or the physiological receptivity of the oviduct of the female. The technique of artificial insemination provides a means of overcoming some of these difficulties. Recently through the use of inbred lines of chickens evidence has been obtained that fertility is influenced by genetic factors. Bernier et al. (1951) have reported on fertility following natural mating with inbred and outbred lines and crosses for three periods in each of two years. These workers found that the origins of females accounted for a great part, if not the greatest part, of the differences in fertility observed. Fertility was neither impaired nor enhanced by …