Poor estrus detection remains a major reproductive problem for lactating dairy cows. As a result, dairy farmers have turned to timed AI and the use of natural service bulls as two breeding programs that do not require estrus detection and are therefore widely used in the United States.

The use of natural service sires reportedly ranges from 43 percent to 75 percent, while the use of timed AI programs is used on 58 percent of U.S. dairies.

But which makes more economic sense? A study at the University of Florida compared the economics of these two breeding programs used on the same dairy farm.

The researchers determined that timed AI was less expensive than the use of bulls in the field study. To arrive at that conclusion, a herd budget accounting for all cost and revenues was created. Net cost during the field study for the natural service program was $100.49 per cow per year and for the timed AI program was $67.80 per cow per year, unadjusted for differences in voluntary waiting period for first insemination (VWP) and pregnancy rates (PR).

After inclusion of the differences in VWP and PR, the economic advantage of the TAI program was $9.73 per cow per year, still a more cost-effective program than natural service sires.

The research was published in the September Journal of Dairy Science.

More information.