Libraries at University of Nebraska-Lincoln


Document Type


Date of this Version



Thesis (M.S.)—University of Nebraska—Lincoln, 1966. Department of Animal Science.


Copyright 1966, the author. Used by permission.


A means of controlling ovulation in domestic animals would be of great value to the livestock producer and the research scientist. It would enable the producer to breed a large number of females during a short period of time. From the practical point of view, this would allow optimum use of labor, equipment, facilities and feed supplies. In addition, it would facilitate the use of artificial insemination in beef cattle and allow more widespread use of outstanding performance tested sires. Control of the length of the calving or lambing season through the control of ovulation would result in a more uniform group of calves or lambs at market time.

The major emphasis in reproduction cycle control, in cattle, has been on the synchronization of estrus. This has been based on the assumption that estrus and ovulation are well correlated. Efforts to synchronize the bovine estrous cycle have utilized three main approaches; inhibition of ovulation and estrus, induced regression of the corpus luteum, and induction of ovulation.

The effect of estradiol benzoate as an ovulation synchronizer was studied in eighty-three synchronized estrous cycles from seventy-seven beef females.

Advisors: D. R. Zimmerman and J. N. Wiltbank