Animal Science Department


Date of this Version



Published in 2006 Nebraska Beef Cattle Report. Copyright © 2005 The Board of Regents of the University of Nebraska.
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Melengestrol acetate (MGA), which is commonly used in the beef industry to manipulate ovarian activity of females, was fed to bulls at two times during development, prepubertal (5.5 to 7.5 months) and peri-pubertal (6.5 to 9.5 months), to determine effects on testes size, scrotal circumference, body weight, and/or hormone production. We can conclude that feeding bulls MGA during the prepubertal and peri-pubertal time can alter body weight and testosterone production.