|Title||Relationship between ovulation rate and reproductive performance in sheep|
|Publication Type||Journal Article|
|Year of Publication||1967|
|Authors||Hulet CV, Foote W.C.|
|Journal||Journal of Animal Science|
|Date Published||May 1967|
|Keywords||ovulation rate, reproductive performance, sheep|
An index or criterion for predicting the future reproductive performance of yearling ewes could be most useful in developing a more efficient sheep industry. It has long been assumed that there is an important relationship between ovulation rate and lamb production, but the repeatability of ovulation rate within a breeding season and between breeding seasons is unknown.
Until recently, surgical procedures have been time-consuming and have discouraged the study of these relationships. However, use of the laparotomy cradle as developed by Lamond (1963) and use of local anesthesia have made practical the examination of reproductive organs in large numbers of live animals.
The objective of this study was to determine the relationship between two ovulation rates measured at a 35-day interval during the peak of the breeding season and the relationship between the mean of these ovulations and previous lifetime lamb production. The relationship between the number of corpora lutea (CL) at the first and second observation periods to the number of embryos resulting from matings at the second observation period was also studied.