Other Genetics Articles
- Upcoming Genetic Base Change: What to Expect
- Pave the way for a more Profitable Next Generation
- Are you choosing the best index?
- Holstein's Fertility Index Shake Up
- Using HHP$ to Enhance Your Return on Investment
- WWS/Select Sires’ Elite Polled Lineup Leads Industry Ranks
- Genetics In The Drivers Seat
- Genetics Impacting Mastitis
- The Practice of Genetic Culling
- Fertility Matters in HHP$ Index
- Lameness Traits: Underused & Underestimated
- Sustainable Genetic Strategy
- The Genetic Strategy to Improve Sustainability
- Somatic Cell Count Impacts Everything
- Where does selecting to utilize feed fit into your genetic plan?
- Is There Such a Thing as a Grazing Genotype
- Inbreeding vs. Genetic Progress
- Mastitis Resistant Pro
- Recumbency in Holstein Calves
- Are All Genomic Tests Created Equal?
- Calf Wellness - The Next Generation
- Wellness and Disease Resistance
- Feed Saved
- Your Genomic Results: Milk Them for All They’re Worth
- Fertility You Can Trust
The first complete bovine genome from a Hereford cow was published in 2009 by Elsik et al. Genomic information has since become a tool widely used in cattle breeding and is potentially the single biggest advance in our industry since the advent of AI. The genomic technology is here to stay and while it is now used across the industry, we are still only beginning to understand what genomic data offers and how we should be utilizing the information it provides. The bovine genome contains over 3 billion base pair combinations around 22,000 individual genes. While many of these genes are common to all mammals, many will also be of particular interest in the breeding of dairy cows, although it will be some time before we completely understand the full role of each individual SNP and gene.
The first, and most obvious, advantage offered by genomics is the improvement in reliability and accuracy of bull proofs for the traits we normally evaluate. The addition of genomic information has resulted in an increase in reliability of most traits from 30% to 70%. (30% is the reliability of a parent verified traditional average, whereas a genomic evaluation is 70%). This offers the opportunity to make more accurate breeding and culling decisions, resulting in an acceleration of genetic gain. These opportunities have been rapidly incorporated by stud companies for sire testing and selection so these advantages can be realized by customers when they select sires to produce the next generation of female progeny.
Access to relatively cheap and rapid genomic tests also allows herds to individually test cows and heifers and to further enhance genetic gain through accurate identification, ranking females and accurately identifying the mothers of the next generation.
With so many choices in the marketplace – how do you pick the best test and the best index to fit your needs? When selecting a genomic test and index several factors should be considered:
1. What reference population is the genomic evaluation based on?
Any genomic test is only as good as the reference population on which it is based, so consider the size of the reference population. Is the reference population representative of the type of cattle a producer wishes to breed? Many low-cost tests are often based on smaller, and potentially poorer, reference populations that may only be specific to a particular testing laboratory or region.
2. Is the test a one-off evaluation, or will the genome be registered with and evaluated by a validating organization such as the Council on Dairy Cattle Breeding (CDCB)?
Genetic information for animals is continuously being updated and reevaluated. We want to ensure that we can always get the most up to date information on our females. A one-time delivery of data is not recommended, as it will quickly be out of date and no longer accurate. Official registration will most likely carry a fee and increase the cost of the test but will ensure that the animal’s genetic evaluation can be updated as more information about that individual and her relations becomes available throughout her lifetime.
3. What traits are to be evaluated?
Before genomic testing, the industry had already begun to provide evaluations for some health traits and to incorporate these traits into selection indices. However, these were based on phenotypic data with limited knowledge of which genome regions were influencing those traits. For genomics to have a true and lasting value, it should allow us to access and explore regions of the genome that were previously unknown. We must then build upon those findings to improve existing traits and create new and more meaningful ones. More expensive tests are typically provided by companies conducting ongoing research into new and novel aspects of the genome, allowing them to provide information to improve the accuracy of existing traits and seek out new ones. If we only use genomic tests to evaluate for existing traits, then we miss out on opportunities to make our cows healthier and more productive.
For these reasons, World Wide Sires recommends the CLARIFIDE® genomic evaluation from Zoetis as the preferred option for customers interested in genomic testing their herds. Logically, if a herd is choosing a test that provides the best genomic assessment available, they would also want to make breeding decisions based on an index that best utilizes those evaluations. For more guidance into choosing the right index for your farm, check out https://wwsires.com/resources.
For many decades, dairy producers have asked only two things of genetic companies: high producing cows, and disease free, healthy cows, both of which are now within our ability to provide. In the article published by Mc Neel et al., 2017, which validates the genomic predictions for the wellness traits unique to DWP$®, the authors state, “These results indicate that wellness trait information of young calves and heifers can be used to effectively predict meaningful differences in future health performance. Improving wellness traits through direct genetic selection presents a compelling opportunity for dairy producers to help reduce disease incidence and improve profitability when coupled with sound management practices.”
