Breeding heifers on body weight alone may not be in your best interest, according to Pat Hoffman, dairy specialist with the University of Wisconsin-Madison. He shared information about heifer breeding criteria and management during a recent Professional Dairy Producers of Wisconsin webinar.
When artificial insemination became a common practice in the 1960s and ‘70s, body weight surfaced as the ideal breeding criteria. Using body weight as the guide helped avoid heifers being bred too late and lessened rearing costs.
Unfortunately, breeding by weight alone can be challenging if accurate weights cannot be obtained. Both scales and heart girth tapes have room for variance, along with the component of human error. Inaccuracy and labor intensity can make procuring accurate body weights of individual heifers difficult. In addition, there can be normal genetic variance of body weight within a breed.
Hoffman suggested a renewal in the thought process by adding age back into the equation. Farms could prescreen groups of heifers at 12 months of age for adequate body weight (850 to 900 pounds for Holsteins). If most are at the appropriate weight, the group could be bred beginning at 13 months of age. If, as a group, they are lighter than that, heifer management should be evaluated and changes made to ensure future groups reach the desirable weight range at prescreening.