A comparison of the Fat Lean Meter (CGM), the ultrasonic device Pie Medical 200 and the Piglog 105 for estimation of the lean meat proportion in Piétrain carcasses

Abstract

A comparison of the Fat Lean Meter (CGM), the ultrasonic device Pie Medical 200 (PIE) and the Piglog 105 (SFK) for estimation of the carcass lean meat proportion was realized with 307 Piétrain and negative-stress Piétrain. The day before slaughter, carcass lean content was measured with two types of ultrasonic devices on the live animal: the Piglog 105 and the Pie Medical Scanner 200. The carcass lean meat content was estimated by CGM at the slaughterhouse. The effect of the machine was highly significant ( P<0.001) for the carcass lean measurements. The percentages of lean meat were 65, 65.7 and 63.9%, respectively, for CGM, PIE and SFK ( P<0.05). The effect of the machine×genotype interaction was highly significant ( P<0.001). Regardless of the machine type, the carcass lean content increased from homozygote negative stress (CC) to heterozygote negative stress (CT) and from CT genotype to homozygote positive stress (TT). The effect of machine×sex interaction was also highly significant ( P<0.001). For each machine, gilts had more lean meat percentage than barrows ( P<0.05). The bias between each apparatus was significantly different according to the halothane genotype sensibility ( P<0.01), whereas the sex influenced only the difference between CGM and PIE lean meat content and the absolute value of this difference. The PIE and the SFK lean value overestimated the CGM lean, respectively from 52 to 67% and from 52 to 65% of CGM lean, whereas the PIE overestimated the SFK lean.