Body Composition Evaluation

Real-Time Ultrasound Measurements for Body Composition Traits in Iowa Cattlemen’s Association Test Station Bulls

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Abstract

The Iowa State University Department of Animal Science has scanned the Iowa Cattlemen’s Association (ICA) centrally tested bulls for the past six years. As the beef industry moves to value-based marketing, more emphasis will be placed on carcass yield and quality traits in genetic selection decisions. Databases must be designed that will allow the beef industry to develop appropriate adjustment factors for the raw measurements. The ribeye area (REA) and percentage-fat measurements are adjusted to 365 days using a linear age-adjustment formula. The formulas are breed-specific and determined from the ICA bull-scanning database. External fat thickness is not adjusted. The common endpoint allows for a more direct comparison of the bulls. Sufficient realtime ultrasound data taken on the ICA test bulls exist to develop linear age-adjustment factors for at least three breeds: Angus, Charolais, and Simmental.

Keywords: ASL R1436

How to Cite:

Wilson, D. E., Rouse, G., Steinkamp, K. & Greiner, S., (1998) “Real-Time Ultrasound Measurements for Body Composition Traits in Iowa Cattlemen’s Association Test Station Bulls”, Iowa State University Animal Industry Report 1(1).