Effects of Temperament & Animal Handling
by Troy Smith for Angus Productions Inc.
NASHVILLE, TENN. (Aug. 6, 2010) — Nearly every cattle producer has experience with animals whose temperament is such that they become excitable when handled. Many producers are inclined to rid their operations of bad actors for safety reasons. According to Oregon State University animal scientist Reinaldo Cooke, cattle temperament may also have productive and economic implications.
In addition to altered behavior, Oregon State's Reinaldo Cooke said temperamental cattle may also experience changes in body physiology, and those changes could affect fertility.
In addition to altered behavior, Cooke said temperamental cattle may also experience changes in body physiology. Hormones are released during a stress reaction and those hormones influence growth, health and reproduction.
“Cortisol blood levels increase in response to stress, along with epinephrine and others. It’s the body’s way of preparing the animal for flight or fight. Heart, respiratory and metabolic rates go up, and the animal’s nutrient requirements increase as well,” Cooke explained.
Indirect effects, he added, include reduced feed intake and reduced performance. The hormones released also include those that influence the estrous cycle. So poor temperament often leads to poor reproductive performance both as a result of stress related effects on nutritional status and influences to the physiological mechanisms controlling ovulation, conception and establishment of pregnancy in females.
Cooke cited studies in Florida showing how Brahman-influenced heifers with calm temperament reached puberty sooner than more temperamental heifers. Mature Brahman-influenced cows with excitable temperament were less likely to become pregnant during the breeding season than calm cows. Brahman influence is generally associated with greater variation in temperament, but Cooke says Oregon studies involving Hereford-Angus crossbred females produced similar results.
One strategy to improve temperament and benefit reproduction in beef females is to acclimate or adapt cattle to human handling. Studies have demonstrated positive response to an acclimation process by replacement heifers. However, acclimation to handling by humans is less effective.
“My advice,” Cooke said, “is to include temperament in criteria for selection of replacements. Secondly, try to become more familiar with your heifers. Get them used to human interaction while they are young.”
Editor's Note: This article was written under contract or by staff of Angus Productions Inc. (API), which claims copyright to this article. It may not be published or redistributed without the express permission of API, publisher of the Angus Journal, Angus Beef Bulletin, Angus e-List and Angus Beef Bulletin EXTRA. To request reprint permission and guidelines, contact Shauna Rose Hermel, editor, at 816-383-5270.