You might want to rethink evaluating heifer-breeding success based on the specific age, height or weight of heifers at the start of breeding. University of Wisconsin Extension Dairy Specialist Pat Hoffman has an alternative suggestion.  He says a more effective metric is to measure the age variance in heifers after they become pregnant.  The goal: as little variation as possible.

It’s that age spread -- caused by missed heats, re-breedings and immature heifers – that’s really costly, says Hoffman. 

Hoffman suggests a benchmark of heifers reaching 850 to 900 pounds by 12 months of age. If this goal is achieved, animals can be inseminated on the first standing heat after 13 months of age.  The ultimate success of the breeding program then should be evaluated on subsequent pregnancy efficiency and age at which pregnancy is achieved.  “Reducing variance in pregnancy age reduces the variance of days on feed, age of first calving and rearing costs,” says Hoffman.

Finally, he emphasizes the importance of an exit strategy.  Many producers are imposing a three- or four-straw limit for repeat breeders, especially in today’s climate of heifer abundance and high feed costs.  “It may be better to cull the heifer and simply cut future losses,” he says.

You can read more of Hoffman’s comments in this article from Vita Plus Corporation’s Starting Strong newsletter.