Estimation of carcass chemical composition in beef-on-dairy cattle using dual-energy X-ray absorptiometry (DXA) scans of cold half-carcass or 11th rib cut.

Assessment of the water, lipid, protein, mineral, and energy contents of beef carcass allows for an understanding of the bovine growth physiology and is key to determining the carcass's commercial value at the slaughterhouse. Direct measurement of the carcass chemical composition requires postmortem grinding and homogenization of a half-carcass to perform chemical analyses. This reference method is expensive, time-consuming, and destructive of edible meat. The aim of the present study was to develop an alternative and nondestructive method to determine carcass chemical composition based on image scans obtained using dual-energy X-ray absorptiometry (DXA). Equations were calibrated to estimate the carcass composition based on the DXA scans of a whole half-carcass or a single-rib cut in an accurate, precise, fast, and reproducible way. These were established for seven types of beef-on-dairy cattle of different sexes and breeds of sire, which are among the most commonly used in specialized beef-on-dairy fattening production systems worldwide.