Dr. Glenn Selk, Oklahoma State University Emeritus Extension Animal Scientist, offers herd health advice as part of the weekly series known as the "Cow Calf Corner" published electronically by Dr. Peel and Dr. Glenn Selk. Today, Dr. Selk attempts to persuade producers to strongly consider temperament when making culling decisions in their herd, asserting that ill-tempered cattle can adversely affect profitability.
"October is a traditional weaning and culling time for spring-calving herds. Weaning for value-added calf sales is already underway. This is a time when producers decide which cows no longer are helpful to the operation and which heifer calves will be kept for future replacements. Selecting against ill-tempered cattle has always made good sense. Wild cattle are hard on equipment, people, other cattle, and now we know that they are hard on the bottom line.
"Mississippi State University researchers (Vann and co-workers. 2006. Southern Section of American Society of Animal Science) used a total of 210 feeder cattle consigned by 19 producers in a 'Farm to Feedlot' program to evaluate the effect of temperament on performance, carcass characteristics, and net profit. Temperament was scored on a 1 to 5 scale (1=nonaggressive, docile; 5=very aggressive, excitable). Three measurements were used: pen score, chute score, and exit velocity. Measurements were taken on the day of shipment to the feedlot. Exit velocity is an evaluation of temperament that is made electronically by measuring the speed at which the animal leaves the confinement of the chute. Exit velocity and pen scores were highly correlated. As pen scores increased, so did exit velocity. As pen score and exit velocity increased, health treatments costs and number of days treated increased, while average daily gain and final body weight decreased. This outcome makes perfect sense. Other studies have shown that excitable temperament can diminish immune responsiveness, with more temperamental calves having a reduced response to vaccination when compared with calm calves.