Submitted to: Beef Improvement Federation Proceedings
Publication Type: Proceedings
Publication Acceptance Date: June 1, 2011
Publication Date: August 1, 2011
Citation: Vann, R.C., Loyd, A.N., Burdick, N.C., Carroll, J.A., Welsh Jr, T.H., Randel, R.D. 2011. Temperament assessment provides insight into future health and growth performance of beef cattle. Proceedings of the 2011 Beef Improvement Federation Annual Research Symposium, June 1-4, 2011, Bozeman, MT. p. 75-81. Interpretive Summary: A series of collaborative studies were conducted involving scientists from the Livestock Issues Resarch Unit, Texas AgriLife Research and Extension Center-Overton, Texas AgriLife Research-College Station, and Mississippi State University in order to elucidate mechanisms in which temperament affects stress and immune responses as well as production traits in beef cattle. By combining an objective (exit velocity) and a subjective (pen score) method to measure temperament, we have created a temperament score to classify cattle based on temperament. Temperament score has been utilized to identify the most calm and most temperamental cattle. Our group has been able to classify animals based on temperament score in order to determine the effect of temperament on aspects of animal production (growth and carcass characteristics) as well as animal health and immune function. Additionally, we also studied the effect of temperament on the response of cattle to common stressors imposed throughout the production cycle, such as handling and transportation. Through an understanding of how temperament can be measured, and how temperament can affect various components of production, selection methods can be employed to reduce the negative effects of temperament on cattle production costs. Therefore, this information will be of interest to both scientists and producers working in the area of beef cattle production with specific focus on animal behavior, stress, and immune responses.
Technical Abstract: Throughout the productive life of beef cattle many stressful events occur (e.g. branding, castration, vaccination, and tagging) coupled with weaning, social mixing, and transportation. These stressfull events have been reported to induce secretion of several of the prominant stress-related hormones: cortisol, epinephrine, and norepinephrine. Acute stress is not necessarily detrimental to the health of an animal, and may even be beneficial. However, chromic stress can negatively impact growth, reproduction, and immune function. Therefore, minimizing adverse consequences of multiple stressful incidents, as well as identification of animals that may react differently to multiple stressful events, may be beneficial to the health and growth of beef cattle. The effect of animal temperament on health and performance is an area of increasing research interest. Correlations between temperament and concentrations of stress hormones have been reported. In addition, temperament can have negative impacts on growth, carcass traits, and immune function in cattle with less desirable temperaments. Multiple studies have provided valuable information on the relationships between cattle temperament, transportation, immune challenges, and production traits over the last six years. Temperament assessments of beef cattle can be comprised of several subjective and objective tests; however, our studies have primarily focused on the following three measurements: 1) chute score, 2) pen score, and 3) exit velocity. Temperament is a moderately hertiable trait and improvements in overall herd temperament and production efficiency can be made relatively quickly in a practical beef production situation. Data suggest that objective measures of temperament assessment may be more useful than subjective methodologies alone. Furthermore, a combined temperament score (an average of subjective and objective measures) provides a more complete assessment due to the fact that it accounts for more than one aspect of cattle behavior. These proceedings describe the work competed by our collaborative group regarding the measurment of temperament and how it can affect immune function, the response of cattle to various stressors, and overall animal productivity.