Anyone who handles cattle on a ranch or in a feedyard will recognize that calm animals are easier and safer to manage than wild, aggressive ones. Research results now show that the impact of cattle disposition reaches well beyond convenience, influencing economic traits in the feedyard and the ultimate value of finished cattle.
Over the past three years, Iowa State University researchers and Tri-County Steer Carcass Futurity staff evaluated 13,315 calves fed at eight southwest-Iowa feedlots. Evaluators looked at how disposition affects feedlot gain and carcass quality. The steers and heifers were consigned by cow-calf producers representing 12 states in the Southeast and Midwest. Individual cattle were weighed upon arrival to the feedlot, after 28 to 35 days, at re-implant and prior to harvest.
Each time the cattle came through the processing area, except for arrival processing, the researchers evaluated their behavior and assigned a disposition score using the Beef Improvement Federation six-point scoring system. In this system, a score of 1 equals very docile and 6 equals aggressive. For analysis, the researchers grouped animals in three classifications, with scores of 1 and 2 rated as docile, 3 and 4 as restless, and 5 and 6 as aggressive. Participating feedlots used typical diet and health programs. TCSCF staff sorted the cattle for harvest when the cattle were visually evaluated to have .40 to .45 inches of fat cover.
Data from this study showed significant trends between temperament and carcass quality grades (see table above). Docile cattle are more likely to reach upper two-thirds Choice or higher, while nervous to aggressive steers were more likely to produce Select and Standard carcasses. Docile cattle also demonstrated better average daily gains and feed efficiency than aggressive cattle.
Earlier research at Colorado State University showed that more excitable animals had more borderline dark cutters and tougher meat characteristics than animals with calm temperaments. Excitable animals had carcasses that exceeded the foodservice industry’s acceptable threshold for tenderness 40 percent of the time, compared with 13.7 percent for steers with temperament rankings of 1 to 3. Following the same trend, 25 percent of highly excitable cattle produced dark-cutting carcasses, compared with 6.7 percent for calm cattle.
As with most traits in beef production, part of the final product is inherited from the sire and dam, and the other part is influenced by management and environment.
Disposition or temperament is a moderately heritable trait, so producers can make improvements through genetic selection. Good animal-handling practices throughout the production system also can improve the disposition of cattle and reduce the negative effects of stress during shipping and processing.
Darrell Busby is an extension specialist for Iowa State University.