Pat Hoffman – Goals of Raising Replacement Heifers

Genomics is an emerging technology, and those using it are learning as they go. The application of genomics in a commercial herd makes the most sense with heifers and calves, said University of Wisconsin-Madison’s Pat Hoffman.

Preparing a sample for a genomics test can be as simple as plucking a hair sample from the calf’s tale or using blood drawn during a sample for antibody transfer.

Samples are due the first of each month, and labs can turnaround a report in about 30 to 40 days.

This report, costing about $35 to $40 per animal, can save producers from spending money on raising and breeding a heifer that is genetically inferior.

Hoffman illustrated this with a photo of four calves: three had positive gPTA milk yield, while the fourth had a negative gPTA milk yield. The culling of the negative calf would increase the genetic progress of the group of calves by threefold, he said.

Hoffman pointed out other areas where progress was being made through the use of new technology and new research.

Precision feeding in heifers, for example, has increased feed efficiency while reducing feed usage and manure excretion.

Hoffman also shared findings from 2009 and 2010 studies that indicated feeding supplemental phosphorus to heifers may not be necessary.

Researchers compared a group of heifers fed with no supplement (about 0.28 percent phosphorus in the ration) with a group supplemented with phosphorus (0.38 percent P). The studies showed no significant difference in bone growth, bone density or, upon entering the milking herd, in first lactation milk production.

He urged producers to continue to educate themselves by reading up on new technology and research and engaging in discussions with fellow farmers, veterinarians and nutritionists.

“Genomics testing is only a few years old,” he said. “It’s something that emerged quickly and is continually emerging, but so was A.I.”