Vitamin A as a Factor Affecting Fertility in Cockerels

Abstract

INTRODUCTION THERE exists at present a good knowledge of the effects of diets deficient in vitamin A and its precursors on poultry and other species of domestic animals, including effects on reproduction. There is an abundant bibliography on this point referring to the hen, and it is concerned as much with naturally occurring deficiencies as with those induced experimentally, and gives a good understanding of the effects on intensity of production, egg quality, fertility and hatchability. The established facts have been generally accepted by poultry keepers and the inclusion of a vitamin A supplement has become common practice in poultry nutrition, the supplement being either in the form of a concentrate or a constituent which has a naturally high content of this vitamin. In spite of our knowledge of incubation technique and of the factors affecting fertility, the overall percentage hatchability, of total eggs set, for the hen and other …