The Iodine Requirements of the Breeding Hen

Abstract

IN THE preceding paper (Rogler et al., 1961) an accurate evaluation of the iodine requirements for reproduction could not be obtained because of the prolonged time required to deplete hens which had been reared on a commercial growing ration of their iodine stores. Thus, in this investigation, hens that had been reared on an iodine deficient diet were used to study the requirements by the same measurements as listed in the preceding paper. One hundred, 4-week-old White Leghorn pullets, which had been fed a commercial starting ration from day-old to 4 weeks of age, were placed on an iodine deficient growing ration until sexual maturity. At sexual maturity, 75 selected birds were placed in individual cages and given an iodine deficient breeder ration until the start of the experiment. The composition of the grower and breeder rations is given in Table 1. The 75 birds were later divided…