Allometric growth of ½ Dorper + ½ Santa Inês lambs slaughtered with different subcutaneous fat thicknesses

Abstract

The objective of this work was to evaluate the allometric growth, the correlation of the cuts with the half carcasses, and the muscularity index of the leg of ½ Dorper + ½ Santa Inês lambs slaughtered with 2.0, 3.0, and 4.0 mm of subcutaneous fat thickness (SFT). Twenty-four non-castrated male lambs were used, being distributed according to their weight into three collective pens. Slaughtering occurred as the lambs reached the SFT predetermined by ultrasound. The half carcasses were weighed, dissected, and separated into five cuts: neck, shoulders, rib, loin, and leg. These cuts were dissected and weighed into muscle, subcutaneous fat, intermuscular fat, and bone. In the shoulders, lambs with 2.0 and 4.0 mm SFT showed early growth. In the rib, this early precocity was observed in lambs with 4.0 mm SFT. The leg showed isogonic growth in lambs with 3.0 and 4.0 mm SFT and was the cut that best correlated with the half carcass, regardless of the SFT. The slaughter of ½ Dorper + ½ Santa Inês lambs with 4.0 mm of subcutaneous fat allows obtaining a better allometric growth of the shoulder, rib, and leg cuts, as well as a better leg muscularity index.

Allometric Growth Patterns of Body and Carcass Component in Docked and Intact Karadi Lambs

“…These results are in agreement with Sabbioni, et al, (37) who reported that the growth coefficient of loin cuts was early growth. Also, Santos, et al, (39) found that the loin proved to be an early growth rate in lambs slaughtered at 33.5 and 42.8kg. While, the growth coefficient of flank cuts in docked lambs is significantly less than one (0.990) indicating that grew at slower rate than the carcass, on the other hand, the b value in undocked lambs was significantly greater than one (1.610) demonstrated high impetus and late maturing tissue.…”