Dairy producers have had the opportunity to test their female animals with the low density 3K SNP genomic test since September 2010. The 3K genomic test provides an estimate of an animal’s genetic merit for many traits, including milk production and Net Merit (NM$). The 3K genomic test, as one of the several available genomic tests, works by comparing an animal’s DNA to a database that associates DNA patterns with genetic merits of traits. A genomic test can, therefore, provide a fairly accurate (reliable) estimate of an animal’s genetic merit early in her life without any other data, such as her own phenotypic records or information from parents of siblings. Genomic test kits that help a producer collect a DNA sample and send it to a processing office are sold by various vendors, for example by the Holstein Association USA and Pfizer Animal Health. The genetic merits of the traits of the animal that is tested are then calculated by USDA. The producer gets the results back within a month or two. As of August 2011, approximately 45,000 animals have been tested with the 3K genomic test, most of them females. Still many dairy producers wonder if the 3K genomic test might have value on their operation.
The benefits of using a 3K genomic test include discovering or confirming parentage for mating decisions and selecting candidates for embryo transfer. This article from the University of Florida explores how dairy producers that primarily sell milk might benefit from using a 3K genomic test on young calves by selecting which calves to raise as replacements. Non-selected surplus calves would be sold at an early age. The increase in reproductive efficiency and use of sexed semen is producing many heifer calves on many dairy farms so choosing which calves to raise based on their genetic merit, among other factors such as early life health events, has become a real option that needs to be considered.
“Some ideas on the use and economic value of the 3K SNP genomic test for calves on dairy farms” appears in the summer 2011 University of Florida Dairy Update.