# Cattle’s Social Rank Throughout the Transition from Rangeland to Fattening Affects Beef Quality

## TL;DR

This study shows that the social rank of cattle during their transition from rangeland to feedlots affects beef quality, particularly color and pH.

## Contribution

The study introduces a method to link cattle social rank with specific beef quality metrics using behavioral and meat analysis.

## Key findings

- Dominant cattle showed behaviors that negatively impacted beef color and pH.
- Social rank was strongly correlated with beef color variables like chroma and ΔE.
- Linear discriminant analysis classified cattle into social ranks with 95% precision based on beef quality metrics.

## Abstract

Regrouping cattle during pre-slaughter handling disrupts their social order, leading to social stress, especially when cattle move from rangeland to feedlots, affecting beef production. We observed the behavior of 20 heifers at three key points: 72 h after transportation, six weeks during fattening, and while they waited at the slaughterhouse. The heifers were classified as dominant (D) or subordinate (S) based on their behaviors. Key factors used to distinguish between groups included pH at 45 min postmortem, drip loss at 0 days, final chroma, and change in color. A strong link between social rank and various aspects of beef quality such as color, pH, and water holding capacity, was found. The discoloration and chroma of beef were different between the dominant and subordinate animals. The dominant heifers tended to show behavior that negatively influenced beef quality, such as its color and pH. Social rank plays a large role in how cattle behave and beef is produced.

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.