Selenium and Glutathione Peroxidase Distribution in Bovine Semen and Selenium-75 Retention by the Tissues of the Reproductive Tract in the Bull1, 2, 3

Abstract

In order to compare the distribution of selenium and glutathione peroxidase (GSH-Px) in bovine semen and to determine the stage at which selenium is incorporated into bovine spermatozoa, 3 bulls were each injected with a single dose of ^{7 5}Se-selenite. After injection, radioactivity and GSH-Px activity in blood and semen were monitored for a period of 75 days. For all bulls ^{7 5}Se was detected in seminal plasma 6 h postinjection and levels in the seminal plasma exceeded blood levels by 24 h postinjection. Radioactivity increased rapidly in the seminal plasma for the first 10 days following injection and then decreased slowly for the remainder of the collection period. Between Days 15 and 20 postinjection, ^{7 5}Se increased in the spermatozoa. GSH-Px activity was present only in blood and seminal plasma.