ABSTRACT
Accurate detection of estrus is essential for dairy producers to maximize the benefits derived from using artificial insemination. Heat-detection records are but a part of the reproductive records that should be part of the overall herd records. Signs of heat vary among cows and for individual cows. Several studies have indicated that the frequency of mounts escalates if more than one animal is coming into heat simultaneously. Reproductive inefficiency is not a direct out-of-pocket expense to dairymen, but suboptimal reproductive performance costs the dairy industry an estimated one billion dollars annually in the US Practical heat detection aids are orange chalk on the tail base, or mount detectors glued on the back. Various methods have been developed to render bulls functionally sterile. A good identification program complements a good record-keeping system. Heat-detection records are but a part of the reproductive records that should be part of the overall herd records.
