Accurate records breed success

June 18 2019

By Melissa Stephen, DairyNZ genetic evaluation developer

Are the heifers you choose to keep the ones you think they are? Save yourself time and money by using DNA testing to match calves to parents, writes DairyNZ genetic evaluation developer Melissa Stephen.

Mistakes can be costly

Accurate record keeping is essential if you want to avoid costly mistakes. Parentage errors can quickly add up to big losses, both within an individual herd and across the whole sector.

During a busy calving season, accurate record-keeping can be tricky. A 2011 study of 97 farms showed that about two in every 10 calves were incorrectly matched with their sires and/or dams. DNA testing can correct these errors before they cost you money. The compounding nature of genetic gain means the impact of  low genetic merit heifers is perpetuated in their progeny long  after the animal has left the herd. Mis-parentage in your herd   also creates risk at mating time, as management of inbreeding is compromised.

In addition to within herd costs, incorrect parentage records mean a large proportion of daughters assigned to an

individual sire will not actually be his. This undermines pedigree information which forms the foundation for genetic evaluation, ultimately hindering genetic progress in the national herd.

Worth the investment

For a relatively small investment (about $30 per calf), DNA testing checks the genomic profile of a calf against its likely  sire. If they don’t match, the calf’s profile is compared to other possible bulls, and the true sire determined.

Genetic progress worth big money

Genetic improvement has a direct economic value to farm profitability. Each year, genetically superior heifers enter the milking herd. These animals add value, initially through their own performance, and subsequently through the genetics passed on  to their daughters.

Assuming the average rate of gain over the next 10 years will  be $11/cow/year, this value will accumulate to around $250,000/ herd, or $3 billion across the dairy sector.

Why DNA test?

• Provides peace of mind that sires for each replacement heifer is
• Confirms the mothers of your heifers (note: this costs more than a standard DNA test).
• Ensues that the data generated by your herd adds value to national genetic evaluations.

For details on how pedigree influences evaluations, visit dairynz.co.nz/parentage

Originally published in Inside Dairy June