Effect of thiouracil produced hypothyroidism on semen and testes of dairy bulls

This investigation of the relation of the thyroid to reproductive physiology in dairy bulls was begun in The University of Tennessee Department of Dairying in the latter part of 1950. The phase of this investigation reported here deals with the attempts to feed dairy bulls methylthiouracil at a level necessary to produce mild hypothyroidism, and to observe the effect upon libido, seminal characteristics and glandular tissue changes as compared to that of normal bulls.