Goitrogen Administration Research Articles

Response of inbred lines of chickens.

IT HAS long been known that there are wide species, sex and age differences in thyroid activity. It is also known that environmental factors such as season and temperature, iodine intake, pituitary activity, administration of goitrogens and the alteration of endocrine activity by other means may have a profound effect on thyroid function. In recent years evidence has been accumulating with respect to the influence of genetic makeup or constitution on thyroid function within species. During the past half century poultry breeders have greatly improved the type, productivity and efficiency of the various breeds of chickens such as the White Leghorn, Barred P]ymouth Rock, Rhode Island Red, New Hampshire and others. In addition, they have developed strains or lines of these breeds which are especially noted for such characteristics as egg number, egg size, rate of growth, rate of feathering, and so on. With such changes in phenotype and genotype, it is only logical to attempt to correlate these differences wit...

The Influence of Thyroxin on Growth and Egg Production of Chickens

THIS report is the third in a series on the influence of injected dl-thyroxin on chickens lacking thyroid glands.1As Marine (1922) has pointed out, physiologists for many years have known that the thyroid gland has a profound effect on growth, and they have also been aware of the existence of important relationships between the thyroid gland and the gonads. Within recent years, a number of workers have attempted to increase the efficiency of growth and egg production of fowl by oral administration of iodinated casein, goitrogens, and other chemical agents. The results of some of the earlier of these investigations gave some indication that ingested iodinated protein accelerates growth rates of chicks up to 6 weeks of age, and that egg production is increased by feeding the material to laying hens. However, later reports have failed to give consistent support to these findings. The administration of goitrogens, on the …