Estimation of Rib-Eye Area and Fat Thickness of Beef Cattle with Ultrasonics

Abstract

Rib-eye area and fat thickness were estimated on four groups of live cattle, totaling 203, from ultrasonic measurements and subsequently compared with actual measurements taken from a cross-sectional tracing of the musculature and fat in the carcass. The correlation coefficients between live estimated area and actual rib-eye area varied from 0.58 (P<.01) to 0.89 (P<.01). Mean live animal estimates of right vs. left rib-eye areas of two groups of cattle differed less than mean actual area of right vs. left. The correlation coefficients between live estimated fat thickness and actual fat thickness varied from a low of 0.11 (P>.05) to a high of 0.63 (P<.01). A low correlation existed between measurements of a group of cattle in which the spinous processes were scribed during slaughter. Significant relationships existed between the two methods of measuring fat thickness of the three groups in which the spinous processes were not scribed. A significant relationship existed between rib-eye area measured ultrasonically 5 months prior to slaughter and actual area in the carcass but not for fat thickness. The ultrasonic method is a good method for estimating rib-eye area and fat thickness in live cattle. Copyright © . .