Santa Gertrudis Source January 2025

EMPOWERING BREEDING DECISIONS Continued from 10

from one particular grandparent, then their genetic merit is also more similar to that grandparent. Why Genotyping? Seedstock producers are encour aged to utilize genotyping in the herd improvement program. Having a genotyped cow herd benefits the seedstock producer in several ways. First, it means that the pedigree of current cows are parent verified. Ac curate pedigree is a key step in pro duction and reporting of accurate EPDs. Genotyping of existing cows can identify errors in pedigree, im proving EPD reliability through cor rection of kinship. Typical pedigree error rates, even in very well managed herds, can range from 5 to 10 percent due to inadvertent recordkeeping errors, estray bulls, cows switching calves and even errors in semen se lection from the AI tank. Genotyping tests easily find those errors and often provide a path to resolving the error. Combined, the inclusion of a re vised kinship and construction of reliable pedigrees increases the accu racy and reliability of the EPDs pro duced in the system. Improved EPD accuracies means more reliable mat ing decisions can be made for your genotyped cows, enabling more rapid genetic improvement. Investment in genotyping replace ment heifer candidates prior to selec tion provides an effective way for pro

ducers to plot out their genetic destiny. Genomics adds more accuracy to fe male EPDs than their lifetime produc tion of natural calves for many traits. In today’s fast-moving genetic landscape, time is more valuable than ever. Mak ing investments that help capture ge netic information early in an animal’s life is essential to remain competitive in the seedstock marketplace. SGBI and its members have made sound investments in genetic-improvement tools. Now’s the time to make sure you are using them to your advantage and positioning your commercial customers for profit and success! The incorporation of traditional pedigree and performance data is achieved through the implementa tion of a mixed-animal model that accommodates both multi-breed and multi-trait approaches. SGBI for mally allows percentage cattle into the database and genetic evaluations system. By grouping animals by breed fraction and estimating merit of the various founder groups, the evalua tion effectively accommodates genet ics from various breed sources. Dif

gen. The state-of-the-art system utilizes both traditional pedigree and performance records, combined with genomic data, to compute EPDs. The methodology is a single-step pro cess that seamlessly combines all data sources for genetic prediction. Genomic data is exploited through a process that adjusts the relation ships among related animals based on the genetic material they inherited. Animals always have one-half of their genetic complement from their sire and dam. However, due to random assortment of chromosomes to gam etes and recombination, animals have relationships that vary between 0 and 50 percent with an average of 25 per cent. During egg or sperm cell formation in mammals, haploid cells are formed that have only one of the two copies of each chromosome. During fertil ization, diploid chromosome status, where the cell has two copies of each chromosome, is restored. The ran dom selection of one of the two cop ies of each chromosome results in individuals having a genetic makeup that may not have equal (25 percent) contribution from each grandparent. The evaluation uses that information to adjust predictions of an animal’s genetic merit. It makes sense that if an animal has more genetic content

ferences in environment and management are corrected for through establishment of within-herd contemporary groups. Genetic evaluation utilizing phenotypic records depends on analysis of data where ani mals have had fair competi tion; in other words, an equal opportunity to perform. The basis of genetic evaluation

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The DigitalBeef database includes powerful tools to search for animals of defined merit and test mating decisions, enabling breeders to make efficient and impactful breeding decisions.

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SANTA GERTRUDIS SOURCE

JANUARY 2025