MULTI-BREED GENETIC EVALUATION Powered By BOLT
International Genetic Solutions (IGS) is an unprecedented collaboration between progressive breed associations fervently commit- ted to enhancing commercial pro tability. The collaboration has yielded the world’s largest genetic evaluation of beef cattle with over 17 million animals and 120,000+ genotypes. In keeping with our commitment to the cattle industry, IGS is pleased to announce the IGS Multi-breed Genetic Evaluation powered by BOLT. The new genetic evaluation provides more predictive EPDs, better use of genomics, more accurate accuracy reported with EPDs, all with weekly evaluations. The announcement ushers in a new era in genetic evaluation—an era made possible by a genetic evaluation system dubbed BOLT (Biometric Open Language Tools, owned by Theta Solutions, LLC). The concept for BOLT started in 2014 as a research endeavor between the American Simmental Association and Drs. Bruce Golden and Dorian Garrick. BOLT is, quite simply, the most revolutionary and powerful genetic evaluation system in existence. Its power allows IGS to leverage genetic evaluation methodology that was once thought to be untenable on large databases—methodology that signi cantly improves genetic prediction. In December 2016, IGS published a multi-breed stayability, the industry’s rst EPD using BOLT and the rst single-step methodology applied to a large beef cattle database. Since that time, the IGS genetic evaluation team has worked toward fully implementing BOLT with an automated system that enables weekly evaluations for an entire suite of EPDs. As of May 5th, 2018, ASA is the rst of the IGS partners to publish a full suite of EPDs generated by the IGS Multi-breed Genetic Evaluation powered by BOLT.
Here are the notable changes in the evaluation:
Movement of EPDs and reranking. EPDs and indexes will change. These changes will be more dramatic for younger, lower accuracy cattle. The IGS team has tested the changes and proven the new EPDs result in superior predictions of genetic merit.
Shrinking of EPD range. You will notice a reduction in the range of EPDs for most traits. The IGS evaluation team tested the statistical veracity of the reduction and it has proven to be in line with expectations based on the genetic variation in the population.
Improved use of genomics. With the switch to the BOLT software, IGS will use single-step genomic evaluation on all EPDs. Single-step uses DNA markers, pedigree information and phenotypic data simultaneously in the prediction of EPDs. Previously, molecular breed- ing values (MBVs) were calculated from the genomic information and those MBVs were blended in a separate procedure into the EPD predictions. The single-step method squeezes more information from the DNA markers than the previous approach allowed. Additionally, with single-step, the genomic information will not only enhance each EPD for the genotyped animals but also will be used in the EPD estimates of relatives. It is well established that DNA markers vary greatly in their e ect on traits—ranging from large to virtually no impact. To leverage this biological fact in a statistically advantageous manner, the BOLT single-step method only uses markers that have a meaningful impact on the traits of interest, while ignoring those that have little to no e ect. Research has shown that by using this approach, BOLT reduc- es statistical “noise” and thereby increases the accuracy of the EPD prediction compared to other single-step methods. It is important to note, continued collection of phenotypic records remains a vital part of genetic predictions. DNA testing will never replace the need to record and submit phenotypes. More accurate accuracy. In the previous IGS evaluation platform and all others in existence other than BOLT, the calculation of the accuracy associated with each EPD is achieved through “approximation” methods. It has long been known these methods are a less than optimal approach to the calculation of accuracy—tending to overestimate accuracy. By employing unique computing strate- gies that leverage both software and hardware e ciencies, BOLT performs what was previously unthinkable—utilizing a sampling methodology to calculate what is essentially true accuracy. Unlike approximated accuracies, BOLT-derived accuracies will result in predicted movements associated with possible change holding true over time. This is not the case with the previous IGS software or any other system currently in existence. While the IGS evaluation team and partners are excited to release this new chapter in genetic evaluation, the new genetic evaluation system will only realize its true potential if the selection is made using its EPD and index values. Hands down, there is no better (more accurate) way to select for quantitative traits than an EPD. Economic indexes predict net pro t by weighing the EPD for economically relevant traits coupled with economic estimates. To compete with other protein sources, it is imperative that the beef industry adopts the best science and technology to make better breeding selection decisions.
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