Temperamental cattle acclimate more substantially to repeated handling
2019; Elsevier BV; Volume: 212; Linguagem: Inglês
10.1016/j.applanim.2019.01.001
ISSN1872-9045
AutoresJamie T. Parham, Amy Tanner, Katharine Barkley, Lyla Pullen, Mark L. Wahlberg, William S. Swecker, Ronald M Lewis,
Tópico(s)Meat and Animal Product Quality
ResumoTemperament of cattle impacts efficiency of production systems, including animal well-being. In being heritable, temperament can be augmented through selection. Current methods to evaluate temperament in a production setting include chute score (CS), exit score (ES), and exit velocity (EV), which some producers may find cumbersome to navigate. Even those who utilize these methods may not do so efficiently if initial evaluations are not strong indicators of future temperament. The objectives of this study were to determine whether temperament in animals change under repeated and routine handling experiences, and to estimate the relationships among CS, ES, and EV. Over three consecutive years, a factorial design of two measurement protocols [frequent (F), infrequent (IN)], and three recording periods was used. The F measurements were collected over three consecutive days, and IN measurements only on day one within a recording period. Each year, twenty commercial Bos taurus heifers were randomly assigned to each protocol. Once heifers were weighed, and their heads caught in the squeeze chute, a CS was assigned from 1 (docile) to 6 (aggressive) by three observers. Exit velocity was obtained on release from the chute, and an ES given from 1 (docile) to 5 (aggressive) by the same observers. For all heifers, protocol, event, and their interaction, were compared on day one. For F heifers, event and day within event were instead fitted. For both models, body weight was included as a covariate, with sire and year fitted as random effects. Pearson correlations among measurements were calculated on day one of each recording period separately, and for days combined. Chute score decreased across events and days in F (P < 0.09). Heifers with higher CS on day one had the largest reduction in score. Exit scores and EV changed less over time (P > 0.13) and were highly correlated (r = 0.81), characterizing the same behavior. Correlations between CS and ES (r = 0.14) or EV (r = 0.08) during the first recording period were close to zero (P > 0.05), but increased as CS decreased. Chute score therefore may be more indicative of acclimation to a novel environment than ES or EV. Both CS and ES appear to offer an easy and inexpensive way to quantify temperament in cattle. Heifers became calmer with repeated gentle handling. Producers may avoid unnecessarily culling cattle based strictly on initial response to novel stimuli by allowing acclimation to handling before assessing docility.
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