Ram Semen Production and Characteristics as Influenced by Administration of Thyroprotein

Groups of from three to five rams were treated with thyroprotein during both spring and summer months at dosages sufficient to cause pronounced weight losses during the first weeks of the treatment. The semen of the various treated groups was compared with that produced by control rams. Treatment during the months of April and May had an apparent deleterious effect on semen quality as measured by initial motility, liveability, density, and ability to reduce a solution of methylene blue. During the summer months rams which tolerated the dosage given produced semen which was either equal to or slightly above the semen produced by the control rams in quality. The ability to tolerate thyroprotein was apparently not related to body weight and in some rams in which excessive weight losses occurred following the administration of the experimental materials, deterioration in semen quality was immediate and drastic.