Keywords
heat, estradiol, progesterone
Abstract
This report summarizes the use of various hormones in an attempt to induce greater estrus expression of lactating dairy cows. Average detection of estrus (<50%) in most U.S. dairy herds has been identified as a problem limiting reproductive efficiency. Detection of estrus plays an important role in reproductive management in U.S. dairy herds despite the adoption of fixed-time artificial insemination programs. When estrus was detected by an activity monitoring system or a rump-mounted device, supplementing cows with progesterone before induction of luteolysis resulted in greater intensity of estrus when compared with controls. In addition, administering estradiol cypionate at 24 h after induced luteolysis resulted in greater frequency of estrus expression compared with cows treated with testosterone propionate or controls when assessed by an activity monitor. Activity monitoring systems achieved heat-detection rates of approximately 70% (80% with estradiol) and are likely cost effective for herds achieving less than that level of heat detection.
Recommended Citation
Sauls, J. A.; Voelz, B. E.; and Stevenson, J.
(2016)
"Increasing Estrus Expression in Lactating Dairy Cows,"
Kansas Agricultural Experiment Station Research Reports:
Vol. 2:
Iss.
9.
https://doi.org/10.4148/2378-5977.1325
Rights Statement
