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

Area of Science:

• Animal Science
• Behavioral Science
• Food Science

Background:

• Social stress from regrouping and hierarchy establishment in cattle can lead to aggressive interactions and significant losses in beef production.
• Understanding the impact of premortem social dynamics on beef quality is crucial for optimizing production strategies.

Purpose of the Study:

• To determine the effect of premortem social ranks of bovines during the transition from rangelands to fattening pens on beef quality.
• To investigate the relationship between social hierarchy and specific beef quality parameters.

Main Methods:

• Behavioral evaluation of 20 heifers in three premortem stages using ethograms to classify them as dominant (D) or subordinate (S).
• Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) were employed to analyze the relationship between social rank and beef quality traits.
• Beef quality parameters analyzed included color (L*, a*, b*, chroma, HUE, ΔE), pH, and water holding capacity.

Main Results:

• A strong relationship was found between social rank and beef color, pH, and water holding capacity.
• LDA successfully classified animals into four social ranks with 95% precision using beef quality variables.
• Color variables (ΔE, chroma) and pH showed significant differences between dominant and subordinate animals, with dominant animals' reactivity negatively impacting beef quality.

Conclusions:

• Premortem social rank significantly influences beef quality, particularly color and pH.
• Social dynamics and stress during the transition period are critical factors affecting the final beef product.
• Findings provide insights into managing social stress to improve beef quality in feedlot systems.