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Working Ranch - November/December 2017

LIST The recessive genetic conditions recognized by the American Angus Association include the following: LETHAL Arthrogryposis Multiplex (AM) Neuropathic Hydrocephalus (NH) Sodium Channel Neuropathy (SCN) NON-LETHAL Contractural Arachnodactyly (CA) PRKG2 Gene Mutation for Dwarfi sm (D2) Developmental Duplication (DD) Myostatin (M1) Oculocutaneous Hypopigmentation (OH) Osteopetrosis (OS) For more about the AAA genetic condition policies, check out their online resources at: www.angus.org/pub/GeneticConditionPolicy STEVE OEHLENSCHLAGER / SHUTTERSTOCK With information, education, and strategic policies in place the AAA has been able to reduce the number of cattle carrying genetic defects and continue to improve Angus genetics. were just getting started. Due to strict policies implemented by the AAA, these bulls became unmarketable—so we ended up getting rid of both bulls and semen and our sales dropped during this time. As we learned with subsequent genes being identifi ed and the greater use of DNA testing, genetic recessives can be managed in a breeding program. Our dairy customers do this every day.” “Through the process of testing for various genetic conditions, breeders became more familiar with DNA, testing procedures and how genes are passed to subsequent generations. This probably helped pave the way for genomic testing, which has gained rapid acceptance across the industry, and is moving genetic progress at a much faster pace,” says House. According to Dr. Moser, the peak year for DNA test purchases for AGI was 2014. Currently they test about one-forth as many animals. “The rules did a really good job of eliminating carriers from the population,” Dr. Moser says. “At the time of discovery of some of the traits, some carriers were no longer used and the pace of genetic improvement slowed. Genetic improvement has rebounded since 2010 for a wide variety of traits. There was a short-term cost in genetic improvement but we have been able to make it up while eliminating the worry and economic impact for commercial cattlemen.” Gathering information is the fi rst step in management of genetic conditions. The policies and protocols adopted by the AAA have helped to inform and guide producers, but the success of those rules depends on producers that identify issues and report them. “Our breeders are vigilant,” shares Dr. Moser. “I give them a lot of credit for their willingness to report calves when things aren’t right. Abnormal calves are sometimes born as a result of the environment and are not necessarily a result of genetics. Working with Dr. David Steffen at University of Nebraska, we confi rm parentage, collect DNA, sometimes are able to get pictures and x-rays and we store that information in a very detailed database should there be similar issues in Angus or other breeds. The information is gathered and tracked. We also store our own DNA. We have over 900,000 DNA samples here at the offi ce.” DATA COLLECTION SAVES THE DAY Dr. Moser noted a situation in which an older AI sire in their archives was identifi ed as a potential carrier of Osteopetrosis (OS). “We were able to go to our archives and retrieve a semen sample for testing. He turned out to be free of the condition, and we were able to clear over 100,000 of his descendants in the database as well. It saved a tremendous amount of cost, not having to test every descendant,” reports Dr. Moser. With information, education, and strategic policies in place the AAA has been able to reduce the number of cattle carrying genetic defects and continue to improve Angus genetics. But the last few years have been a DNA crash course. “Today’s customers are very well informed, but it hasn’t been that way very long,” says House. “We, along with our customers, learned ‘on-thefl y’ about genetic conditions and their ramifi cations. I believe today’s level of understanding regarding DNA/ genomics was kick-started in part due to genetic recessives. Are we better off today than we were before these things were identifi ed? I would say yes.” Strategic DNA testing and management allows Angus breeders to produce great cattle that are desirable to the commercial customer. Making intelligent rules to handle the reality of genetic defects has allowed the AAA to stay on top and serve as a model for other breeds when they confront their own genetic defect challenges. 116 I WORKING RANCH I NOVEMBER / DECEMBER 2017


Working Ranch - November/December 2017
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