Commercial dairy producers might think that genomic testing of dairy heifers is only for registered breeders who make a supplemental living selling breeding stock.
Think again, says Tom Lawlor, a geneticist with the Holstein Association. Lawlor was here at World Dairy Expo Wednesday leading a seminar on strategies that utilize genomic testing.
Genomic testing works particularly well in herds that have excess heifers and want to cull or sell low-end genetic potential animals. If those extra heifers aren’t needed to maintain herd size or expansion, savings in feed and labor can be significant by not raising them to freshening.
Lawlor uses an actual example of a producer who tested 46 heifers with no sire or dam identification. The range in Net Merit $ was from -$600 to +$600. The heifers were tested with a 3K chip, which costs about $43 per test.
By culling the bottom 5%, most of whom showed NM$ of less than -$500, the producer raised the average genetics of the remaining 41 heifers in the group by $52.50, for an increased income of $2,153. The cost of testing all 46 animals was $1,978, leaving a profit of $175. And that doesn’t account in feed, labor and costs saved by not raising those extra five heifers.
If the producer culls the bottom 10 animals from the group, he would have been able to raise his NM$ average $92 on the remaining 36 animals, for an income of $3,571. Subtracting the testing cost of $1,978 leaves a profit of about $1,600. And again, raising costs saving would be additional.
If the producer had sire identification on all the heifers, other research shows the accuracy of the pedigree estimate increase. With that information, culling the bottom 10% would increase profitability to nearly $1,000.
Research also shows that if the producer has both sire and dam identification, that parent average will allow him to rank animals. With genomic testing, he then needs to only test the bottom 50% of the group to identify the lowest ranking animals. In other words, he can cut his testing cost in half while having even more assurance that he is making the right decision.
That’s because the Reliability of sire ID is 30% for a trait such as milk production, 35% for sire and dam ID, 60% for sire, dam and genomic testing.