Abstract
The social stress due to regrouping and hierarchy establishment in cattle in the transition from rangeland to feedlots may cause considerable losses in beef production due to aggressive interactions. This study determined the effect of the premortem social ranks of bovines in the transition from rangelands to fattening pens on beef quality. The behavior of 20 heifers was evaluated in three premortem stages: 72 h after transportation, after 6 weeks of fattening, and while waiting at the slaughterhouse. Heifers were classified as dominant (D) or subordinate (S) based on ethograms. The principal component analysis revealed a strong relationship between social rank and beef color (L*, a*, b*, chroma, HUE, and ΔE), pH, and water holding capacity. The linear discriminant analysis of the beef quality variables classified the animals in one of four social ranks (dominant, change to subordinate, subordinate, change to dominant) with 95% precision. pH 45 (-9.163), drip 0 d (-3.917), final chroma (1.773), and ΔE (1.646) obtained high coefficients that determined the separation among the classes. Color variables like ΔE (p = 0.049) and chroma 0 d (p = 0.053) showed significant differences between the D and S animals in the MANOVA. Reactivity in dominants tended to negatively impact beef quality, affecting its color and pH. These findings contribute to a better understanding of how social dynamics impact beef quality during the transition period.