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DNA Matters Tim Kozelsky | DNA & Data Service Analyst | tkozelsky@akaushi.com AKAUSHI BREED GENET ICS

H appy New Year! DNA submissions. Since the convention, you have kept the association very busy. We have processed more than 3,400 samples 2018 ended with a bang concerning

twins are fraternal – not identical – with distinct DNA. The twins share blood when they share the same placenta. Microchi- merism is the primary cause of freemartin heifers. Blood and hormones are shared between the bull and heifer calf, which af- fects the heifer calf’s reproductive system development. Microchimerism also has an impact on DNA testing if blood samples are submitted on twins. Normally, the samples

during these past two months. New calf sub- missions in 2018 will end very comparable to 2017. We should finish with around 18,000 samples. For those of you who are interested in how you stand with the number of samples you sent in, the average submission con- tained about 45 samples; 151 members sent DNA samples this year. Forty members were first-time submitters this year. The average time it takes to get results from the lab has been 25 days. This month, I thought I would address some possible causes of verification fail- ures. First, it is absolutely imperative that accurate records are included with DNA submissions. Yes, DNA can determine par- entage, but we need to have a list of sires to work with. While we are in the transi- tion period of switching from STRs to SNPs DNA testing, there are animals with only one type of DNA profile. If a bull does not have the same DNA testing as its offspring, there will be failures. It is very easy to check the DNA status of your herd. You can simply log into your DigitalBeef account. Each tab under the “Herd” tab has a column that indicates what type of DNA testing each animal has. If you need help logging in or navigating around your DigitalBeef account, please call the office at (361) 238-7218. The next area to look at is microchime- rism – a common term we have all heard I am sure! Actually, it is the scientific term for the blood sharing that takes place in a cow’s uterus between twins. Most bovine

will fail, but there can be instances where the DNA results could be a combination. Oddly enough, microchimerism is only an issue when blood samples are used. Tissue and hair samples are not impacted. Usual- ly, the blood sample will fail the DNA pro- filing process. If you think you have twins, or if you have submitted a blood sample of a calf that is having verification troubles, sometimes a change in sample type will solve the issue. Finally, I would like to explain the pro- cess of DNA verification. DNA is referred to as an exclusionary process. All sires and dams are potential parents until they can be excluded by DNA. To understand exclu- sions, we need to understand how the DNA

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Akaushi Prime Time • Winter 2019

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