We define how cattle behave and react when being handled by several definitions. Temperament, disposition, calmness, aggressiveness and flight zone are all words or terms used to describe this interaction between cow and stockman. Recent studies discussed below all indicate that calm cattle have superior performance and tend to have improved health, leading to more desirable carcasses. In addition to these economic and performance reasons, there are several additional reasons that cattle temperament is a very important selection criteria. As an industry, we are under increased scrutiny regarding how we provide a healthy, clean environment, how we minimize injury, and how we treat and handle cattle with minimal stress. Cattle temperament is an important part of this relationship. Additionally, we are all forced to operate larger herds with less and less help in order to remain viable. Docile cattle move through processing facilities easier, are less prone to accidents and injury, and reduce wear and tear on equipment and facilities.
Measuring temperament. Current systems used to measure temperament include Pen Score, (PS) a subjective measurement based on observing cattle in the pen, where 1=nonaggressive, docile, not excited by humans or facilities to 5=very aggressive, excitable, runs into fences and toward humans. Chute Score (CS), an estimate of temperament based on observing cattle while restrained in the chute with 1=calm and no movement to 5=rearing, twisting, or struggling, and Exit Velocity (EV), how fast an animal leaves the chute after being processed, usually measured in ft/sec. Both pen score and chute score are easy measurements to take, and I've seen several operations score their cattle, especially replacement heifers, during processing. We all notice the outliers, or extremely excitable animals that are aggressive to the stock dog, but it is also important to score all cattle in order to make overall improvements in the herd.
What determines cattle temperament? Genetics definitely tell part of the story in determining cattle docility, but it's probably not the whole story. Australian research indicates that cattle temperament is highly heritable, with both exit velocity (EV) and chute score (CS) being highly heritable, with heritability estimates of 35 percent and 30 percent, respectively. Careful screening of bulls and watching specific bloodlines can definitely help with temperament.
Equally, if not more importantly, is how cattle are routinely handled. Mississippi State data suggests that there are significant differences in animal temperament between farms, or sources. This isn't just a function of genetics, but routine handling. Working cattle calmly and quietly, having an understanding of flight zone and how cattle react to perceived threats, and working cattle slowly all reduce stress on the cattle and improve overall temperament of the herd.
At home, my kids have the perfect example of this. We have a pretty good sized herd of bucket calves, a group of calves that my three kids have raised for the last nine months. These calves walk up to you in the pen and rub against you, just like a pet dog. All three of the kids can crawl on all of these calves, riding them without a halter. These calves came from various sources, but the constant contact with us resulted in very tame calves. We recently put all of our weaned heifer calves in the same pen with our bucket calves. In addition to teaching them where the water tank was, and how to eat from a bunk, the bucket calves also had a calming effect on the heifers, and within a week, the kids could even approach the heifer calves, which hadn't been handled until weaning. That is, all except for one heifer that my oldest son has named "lightning."
Lightning poses an interesting question that all operations face. She is by far the best heifer in the bunch, but it took her seven days before she was calm enough to approach the bunk and eat. While my son is convinced that he will have her tame by Thanksgiving, is she worth keeping? I half-joke with neighbors that our cows HAVE to be calm. I rarely work cattle without at least one of the kids with me, and the cattle have to be calm enough to notice and respect the kids without making it dangerous for anyone. I would argue that in my case, as with several operations, temperament isn't a "convenience" trait. It's an extremely important trait for several reasons.
Temperament impacts calf health. We've always suspected that temperament, defined as "mothering ability," is essential for colostrum intake and adequate transfer of passive immunity to the calf. Several studies show a direct link between colostrum intake of the calf and overall health, both prior to weaning as well as in the feedlot. More recent research from Texas A&M has shown that calm cattle respond better to weaning and feedlot vaccinations, resulting in a better immune response to the vaccine and better overall immune protection.
Temperament and feedlot performance. Studies from Colorado State University, as well as a recent summary of three years data from an Iowa Tri-County Futurity feedlot test suggest that steer temperament affects feedlot gain. The recent Iowa report estimates that "docile" and "restless" cattle had increased feedlot gains valued at $37 and $29 over aggressive cattle. More controlled studies reported by Missouri, Texas A&M and Mississippi State looking at specific groups of cattle are not as clear. Often, the sire effect is larger than the impact of temperament. The difficulty with these studies is that removing the sire effect from a group of cattle (and differences in temperament between sires) also impacts the overall interpretation of temperament results. Because Temperament is a highly heritable trait, it is difficult to separate out the performance and temperament differences between sires.
Temperament and Carcass Quality. There is more conclusive data reported by several universities that suggests that highly excitable cattle tend to have reduced marbling (lower USDA quality grade). Recent studies from Mississippi State and Texas A&M report that cattle with high temperament scores (1=calm, 5=extremely wild/aggressive) have an increased incidence of tough steaks. Although tenderness isn't a current criteria in determining fed cattle prices, it's still an important issue for the industry to address. The 2005 National Fed Beef Quality Audit identified the lack of uniformity in marbling and tenderness as the number one challenge for the industry. Identifying factors that affect tenderness is an important first step.
So how important is temperament? It's difficult to put a dollar value on cattle disposition. If you retain ownership through the feedlot, the Iowa report suggests that calm cattle are worth $50-$60/head premium based on higher feedlot gain and improved carcass quality. Additional considerations that aren't as clearly defiined include the dam's mothering ability and associated calf health and performance as well as convenience and safety issues. I'm not aware of any studies comparing heifer temperament and overall A.I. conception rates, but I suspect that temperament affects A.I. success rate. While temperament may not be at the top of the culling criteria list, recent data suggests it may be a more important trait than once thought. Certainly the industry has identified uniformity, marbling and tenderness as important industry issues, and temperament is most likely a contributing factor in all three.