Genetic but not lean grade impact on growth, carcass traits and pork quality under organic husbandry

Abstract

Organic pig production may be conducted with different genetic types and the carcass outcome can differ in fatness content, however, the contribution of each effect to meat quality characteristics is not well established. The objective of this study was to evaluate two genetic types (Duroc x (Gascon x Duroc), Duroc-sired vs. Pietrain x (Landrace x Large White), Pietrain-sired) slaughtered at a different weights to achieve similar target carcass fatness (90 kg or 105 kg of body-weight, respectively), and the effect of two carcass lean grades (<60% or ≥60% lean) on growth rates, carcass and pork quality under organic husbandry. The daily gain and carcass yield were lower in Duroc than in Pietrain-sired pigs. The post-mortem and ultimate pH, moisture, lightness (L*), yellowness (b*), cooking loss and intramuscular fat content of loin meat were not influenced by genetic type, while redness (a*) and tenderness (shear force) were lower in Duroc than their Pietrain counterparts. Partition tree analysis showed that the highest shear force (≥4.63 kg) and the highest fat depth at Gluteus medius muscle (≥16 mm) were associated with Duroc-sired pigs. The lowest redness (a*<2.23) was associated with leaner (≥60%) pork. The crossbred finishing pig including 75% Duroc genes showed lower growth performance, carcass weight and dressing out than the Pietrain sired crossbreds. Lean grade was not associated with earlier differences in growth, carcass performance or meat quality, except for a tendency for greater compression at 80%force in leaner raw pork.

G. Ripoll is member of the MARCARNE network, funded by CYTED (ref. 116RT0503).