The Influence of Thyroprotein-Feeding on Semen Quality

The effects of hypothyroidism on semen quality have been reported by Shaffner and Andrews (1948). It was shown that the feeding of thiouracil lowered semen quality as measured by both fertility tests and laboratory criteria. On the basis of this work, it was reasoned that the feeding of thyroprotein might improve the quality and/or quantity of semen especially when fed to older males. Therefore, a preliminary study was made on the effects of mild hyperthyroidism on semen production. EXPERIMENTAL Eleven two-year-old Barred Rock males were maintained in individual cages and fed an all-mash diet. Samples of semen were collected weekly and evaluated by the techniques previously described (loc. cit.). Observations were also made on comb area and body weight. After six weeks of preliminary testing, the males were divided into two comparable groups and on April 23, 1947, treatment was begun. A group of six males was fed thyroprotein at . . .