Is Heat Detection the Weak Link in Your Reproductive Management Program?
Dairy Pipeline: July 1995
Ray L. Nebel
Extension Dairy Scientist
The recommendation that dairy herd managers should strive to optimize reproductive efficiency in their herds in order to maximize profits is not a new one. Yet in many herds, reproductive efficiency has continued at levels much below those recommended as more cows have been added and fewer hours have been allotted per cow. Maintaining a high level of reproductive efficiency is required if dairy herd profitability is to be maximized. Reproductive performance of a dairy herd is a function of certain management policies and how well these management policies are implemented in the daily management of the herd. Too often reproductive efficiency is overlooked as a major area where efficiency of milk production can be increased. Milk yield per day of herd life is reduced with longer calving intervals. Cows spend more days in late lactation or more days dry. Fewer calves are born each year. Thus, there are fewer calves available as replacements or for merchandising. Voluntary culling for production is reduced as cows are culled for reproductive reasons. This retards genetic progress and production potential. Generally, veterinary expenses increase as reproductive performance declines. Long calving intervals often result in over-conditioned cows. A 12.5 month calving interval should be the goal for Virginia dairy producers. To obtain a 12.5 month calving interval cows must be bred by 75 days in milk and a conception rate of approximately 2 breedings per conception must be maintained. Low heat detection rates are the number one reason why most herds do not have a 12.5 month calving interval. Now is a good time to review what is the management practices and procedures that are performed on the farm to observe cow in "heat". New tools are available to assist with are even replace visual heat observation.