Barzona Bulletin Spring 2025

From Our Association Secretary

Economically Relevant Traits in Beef Bull Selection Continued from page 1

Golden Hz Farms Barzona: The breed for busy people These cows take care of themselves! It is critical that commercial producers identify their breed ing goals and thus the traits that are economically relevant to them. Selection pressure should be applied to the traits that directly impact profitability, and in the absence of EPDs for these traits, the corresponding indicator trait EPD should be used. Economic selection indices can aid in the selection of sires that excel for firm level profitability under a given produc tion scenario. BB ference. Ultrasonic carcass measurements are a non-destruc tive measure of traits such as intramuscular fat percentage (IMF). Producers do not receive premiums for IMF levels, rather premiums (and discounts) are applied to USDA Quality Grades. Assuming that carcass maturity values are the same, actual carcass marbling is the driver of the Quality Grade. Although IMF is genetically correlated to carcass marbling, it is not the ERT. Birth weight is another great example of an indicator trait. Selection to decrease birth weight in an attempt to reduce the prevalence of dystocia is practiced by numerous commer cial bull buyers. However birth weight does not have a direct revenue source or cost associated with it. The trait that does have a cost associated with it is calving ease (or difficulty). Calving ease is related to the level of assistance needed during calving. Although the two are related, the genetic correla tion between calving ease and birth weight is only between -0.6 and -0.8, suggesting birth weight only explains 36 to 64 percent of the genetic differences between animals for calving difficulty. A commonly misunderstood indicator trait is scrotal circumference. Bulls with larger scrotal circumference mea surements tend to have daughters that reach puberty earlier. However, the relationship between scrotal circumference and heifer pregnancy in Bos taurus cattle is near zero, but slight ly positive (0.20) in Bos indicus breeds. Genomic predictors (Molecular Breeding Values (MBV) or Molecular Value Predic tions (MVP)) can also be thought of as indicator traits. As the genetic correlation between the MBV (or MVP) increases, the more valuable it is as an indicator. However, as these genomic predictions do not have an accuracy of 1, they do not account for all of the genetic differences between animals. Some traits that currently have EPDs are convenience traits (e.g. teat size, udder suspension, docility). Certainly these traits are genetically correlated to ERT, but stronger genetic as sociations often exist between ERT and other indicator traits. For example, cattle that are more docile tend to have higher marbling scores and are more feed efficient, but more direct indicator traits exist to improve feed efficiency and Quality Grade. Teat size and udder suspension can be related to mater nal weaning weight and the probability of culling.

T his newsletter is coming a bit delayed. I am sure you all can sympathize on how busy spring is. That being said, I have members looking for both purebred bulls and females, and even semen for AI use! If you have any available, the office can help you get those animals registered and transferred to new owners. Please remember, we like to see transfers done within 30 days of the animals changing possession. If you have calves that need to be entered before cows are transferred, please get that done ASAP. When the new owner is ready to transfer, those animals will be moved, ready or not. I hope all of you received your membership packets and have returned them. Any new rule changes that you might want to submit need to be in to the office 90 days prior to the annual meeting. The Barzona Breeders Association of America Annual Meeting is Sept. 12-14, 2025, in Ames, Iowa! We will be touring part of the Iowa State University beef facility and getting a pre sentation about carcass grading and quality as well as normal business. Last, remember our new website is www.barzona.org . Mem bers can advertise on the website and be sure to catch up on registrations from the 2024 calving season! BB By Alecia Heinz, Golden Hz Farms, BBAA Secretary Save the Date For the Barzona Breeders Association of America

Annual Meeting Sept. 12-14, 2025 Ames, Iowa

Breeding Stock Available

Matt & Alecia Heinz 2432 250th St Greenfield, IA 50849 smartace007@yahoo.com (641) 745-9170

Alvin & Karen Havens 2429 Orange Ave. Greenfield, IA 50849

www.barzonas.com

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