SELECTIONS - FALL 2008
Putting the Power of Genomics to Work for You
by Jeff Ziegler, genomics program manager
The advancement of biotechnology is rapidly changing the dairy industry. Select Sires’ dedication to be the leader in cutting-edge technology is fulfilling our mission of enhancing dairy herd profitability. Genomics will revolutionize the cattle industry, similar to how frozen semen did in the 1960s.
So what exactly is genomics? By definition, it is the mapping and sequencing of genetic material in the DNA of a particular organism and the use of that information to better understand what genes do, how they are controlled, how they work together and what their physical locations are on the chromosome. While this is complicated in practice, it simply provides a genetic roadmap to more clearly define the animal’s destination.
An animal’s true genetic merit under today’s animal model system has been defined as a combination of the pedigree of that animal, the performance, if any, of that animal, and the performance of that animal’s progeny. We can now add that animal’s DNA markers to the list.
Following the human genome project, the 3 billion base pairs contained on the 30 chromosomes of the cattle genome were sequenced in 2004. This sequence information was used to identify 50,000 representative genetic markers that could effectively identify an animal’s genetic makeup. Testing for this massive number of markers is done on a small credit card-sized chip called the Illumina Bovine SNP50™ chip. Test results from nearly 40,000 of these genetic markers make up an animal’s genotype, the unique genetic identity of an animal. This genotype, along with an animal’s pedigree, individual performance and progeny performance is used to compute a genetic
prediction.
This has been a long-term project that began more than 10 years ago when several A.I. companies, including Select Sires, donated DNA from their sires to a central repository at USDA. Scientists have used this historical collection of tissue samples and developed SNP50 genotypes from more than 7,500 proven sires and associated these with their highly reliable PTA values. These associations, developed from an extensive database of historical results, provide a template for unproven sires’ predictions. USDA research indicates these associations provide a significant boost in accuracy over traditional methods when predicting future PTAs for A.I. sires.
What Does this Mean for You?
For one, you are now provided a more accurate estimation of a sire’s true genetic value, long before he is proven. Nearly all PTAs will have genomic adjustments made and will be labeled as genomic-tested. In doing so, the reliabilities of all genetic predictions are greatly enhanced. The typical production trait PTA reliabilities on unproven sires move from around 40 to 70 percent. Type traits increase from 37 to 65 percent reliability. And the greatest accuracy improvement is for the lower-heritability health and fitness traits. They move from 30 percent reliability to 60 percent. With the added pressure today to build a healthier, longer-lasting, reproductively sound cow, these are huge advantages in accuracy.
How is Select Sires Going to Utilize this Technology?
One way Select is incorporating this technology into our sire program is by identifying the genetic differences between full siblings. Prior to genomic predictions, all flush mates would be assigned the same genetic values. However, once each animal’s gene map is determined, adjustments to each of these PTAs show considerable differences from calf to calf, and at a much higher reliability. This provides our sire department a greater chance of selecting the right full sibling or siblings above and beyond just looking at the animals’ physical characteristics. In essence, we can now look inside an animal, see its truer genetic makeup, and determine if that sire merits proving through the highly successful Program for Genetic Advancement™ (PGA™).
Beginning in January 2009, genomic-enhanced proofs and genomic-enhanced Parent Averages will become the official evaluation. This has all been scientifically proven at a very high significance and will enhance genetic progress for all involved. By utilizing younger, superior genetics with higher reliabilities, you will see a reduction in the generation interval. To adhere to Select’s mission of providing superior products to enhance the profitability of herds, we knew it was important to capture all this technology into a straw of semen.
Therefore, Select Sires introduces gene MAX™, an exciting new product line with multiple benefits. Select has carefully chosen superior, genomic-tested young sires that are approximately 3-years-old. In doing so, these sires have the greatest odds of becoming the breed’s next line of elite proven sires. These sires have official calving ease evaluations, so they are already presorted for use on virgin heifers. To fit your herd’s management style, gene MAX is now available gender SELECTed with conventional semen becoming available in January. gene MAX sires are competitively priced; genetic data elevates their value, yet still not to the degree of highly reliable proven sires.
Our recommendation is to use a combination of several gene MAX sires, similar to our recommendation for any unproven sire use. gene MAX sires offer higher reliability than ever before, but PGA use is still required to gain that extra reliability that we all expect from proven graduates.
The average genomic Parent Average from the initial group of gene MAX sires is already the envy of the industry, so don’t be left out. Our mission is your success and gene MAX is the newest of many tools in the Select Sires toolbox for assured herd profitability.
™Bovine SNP50 is a trademark of Illumina, San Diego, Calif.
™Program for Genetic Advancement, PGA gene MAX and gender SELECTed are trademarks of Select Sires Inc.
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