Subjective methods of quantifying temperament in heifers are indicative of physiological stress

To effectively select for temperament, selection criteria must reflect an animal's response to stress. Subjective measures such as chute (CS) and exit (ES) score provide fast easy assessments of temperament but may be subject observer bias inconsistency. Objective cortisol other metabolites have been associated with increased stress in cattle, especially regarding transportation. Our objectives were identify relationships between objective subjective methods evaluating determine whether change under repeated, routine handling. Over three consecutive years, a factorial design two measurement protocols [frequent (F), infrequent (IN)], recording periods (event) was used. The F measurements collected over days, IN only on day one, within all events every year. Each year, 40 commercial Bos taurus heifers randomly split into the protocols. While restrained chute, behavior quantified using CS. Thereafter body temperature heart rate measured, fecal blood sample collected. These samples analyzed levels serum cortisol, glucose, creatine kinase, non-esterified fatty acids, urea nitrogen. Upon release, ES recorded. For heifers, effects protocol, event, their interaction, compared one each events. assigned F, event also evaluated, many nine observations heifer. both analyses, weight, ambient temperature, wind speed included covariates, sire year fitted random effects. Pearson correlations calculated first combined. Chute (r = 0.24 0.32) 0.26 0.33) positively correlated (P < 0.05) rate, glucose concentration, levels. metabolite that changed concentration time 0.01) kinase due large spike third (52.1 ± 6.5 U/L). Heifers higher scores (CS ES), which coincide greater responsiveness handling practices, tended towards physiological This supports use CS quantify cattle.