Differences in beef cattle temperament could significantly affect value from the feedlot to the plate, according to a Texas A&M University study.
These findings, published in the Journal of Animal Science, show that heifers with calmer temperaments have better feedlot performance and, as a result, higher carcass quality and value than those with more excitable temperaments. This suggests that evaluating temperament could be a useful feedlot management practice with less cost and effort than developing new tools.
Cameron Olson, currently a PhD student in animal science at the University of Alberta, was the lead author on this study, working with primary investigator Dr. Gordon Carstens of Texas A&M University. Olson’s interest in improving beef production efficiency with tools that can be easily adopted drew him to this topic.
“We don’t have to rely on long-term genetic change necessarily for this. A lot of this could be implemented right away,” he says. “The animals inherently have these traits, and it’s up to us to look at how to use them.”
The study examined how temperament upon feedlot arrival relates to feeding behaviour, feedlot performance and carcass traits and value. It also explored the role of breed type in relation to temperament. Newly weaned heifers around eight months of age were used in three trials conducted over three years, with breed influence being purebred Angus, Brangus, Simbrah or Braford. Heifers were used rather than steers based on data availability.
It was important that the animals were sourced from a single location, as past studies on temperament used cattle from multiple locations. This allowed for decreased variation in how the heifers were raised as well as increased uniformity in genetics.
Researchers evaluated temperament by measuring exit velocity when the heifers arrived at the feedlot and at the beginning and end of each trial. Researchers used infrared sensors to time how long it took a heifer to travel 1.8 metres after exiting a squeeze chute.
In addition to using electronic feed bunks from GrowSafe Systems to collect data on feed intake and feeding behaviour for 70 days, heifers were weighed every 14 days, and ultrasound carcass measurements were taken at the start and conclusion of each trial. Measurements included loin muscle area, subcutaneous backfat depth and intramuscular fat percentage.
There was a significant difference in initial body weight, with calm heifers coming into the feedlot heavier than excitable heifers. As a result, these animals were heavier when they came off trial. Calm heifers also had a higher average daily gain.
“That starts to paint a picture of calm animals that are a little bit more efficient compared to animals that are excitable,” says Olson.
This is backed up by the eight per cent difference in dry matter intake between calm and excitable cattle. Calm animals averaged a dry matter intake of 9.4 kilograms per day, compared to the average of 8.7 kilograms per day for the excitable heifers. While there was no difference in residual feed intake between calm and excitable heifers, the gain-to-feed ratio showed that calm heifers gained more per pound of feed consumed, as expected based on the findings for average daily gain.
The study didn’t find a noteworthy difference among the four breeds of heifers in initial or final relative exit velocity. Olson found this a bit surprising, as past research suggests that on average, Bos indicus cattle can be more temperamental than Bos taurus cattle when put through these tests.
“We didn’t find much difference between those different breeds, and we think it’s probably because they were all from the same location,” he says. Another reason may be the lower percentage of Brahman genetics present in the American breeds used in the study, which was only three-eighths.
Temperament results in differences in tenderness and value
Olson says that including carcass traits in this study was important to better understand the topic.
“There isn’t much else out there that looks at the whole scope and follows these animals, from the same environment, through to slaughter and records that carcass information,” he says. “The literature shows that temperament impacts feedlot efficiency and it impacts carcass traits, so we wanted to tie it all together and see if those animals that were more efficient in the feed yard paid dividends as well when they actually made it to the rail.”
The study examined carcass quality, yield grade and tenderness, and found that the effects of temperament also translated into more desirable carcass traits. Calm animals had a greater hot carcass weight, as reflected by their heavier weights while on feed. These cattle also had larger ribeye areas and loin muscle areas and were fatter.
“The yield grade was as expected,” says Olson. “With fatter cattle, you have a significantly higher yield grade, but you also have a higher quality grade, which is what you need to see when you have a higher yield grade in order for those cattle to continue to be profitable.”
Using the Warner-Bratzler shear force test to determine tenderness, they found that temperament resulted in differences in tenderness, seen in the initial test and then after steaks were aged for 14 days. Both tests showed that tenderness was considerably higher in calm cattle.
“We’re not really sure what may have driven those differences, but they exist and it’s something that future research could certainly look at as to why calm animals may have more tender beef than excitable animals,” he says.
They followed this portion of the study with a small economic analysis. Using a grid to price the cattle out based on yield and quality grade, there wasn’t a huge difference in carcass values; however, due to the differences in body weight, the calm animals brought more money per animal than the excitable animals. While excitable animals brought $1,278, the calm animals brought $1,335.
“When we included the Warner-Bratzler shear forces into that marketing grid, we had almost a significant difference between the value per pound between calm and excitable animals, but it really came out to a larger differential between calm animals and excitable animals on a dollars per animal basis.”
More research needed on causes and applications
These findings raise questions about what causes the variations between cattle of different temperaments, as this is not entirely understood, Olson says.
“Is it stress hormones that are controlling a lot of this? Is there some other physiological phenomena that we aren’t aware of yet that’s driving these differences in how animals gain and how they carcass out?”
Feeding behaviour is known to sometimes predict feedlot performance. Cattle that are at the bunk longer and more often generally gain more. Olson believes there’s more to explore regarding how these behaviours interact with temperament.
“Are animals that are more excitable less likely to be competing for food? Are they less likely to be right up at the bunk when feedlot machinery passes by?”
Further research is also needed on how cattle sorted into groups based on temperament on feedlot arrival interact with each other, though there is anecdotal evidence on how a calm heifer can cool down a group of excitable heifers, or vice versa.
“Are the feedlots actually going to be able to implement this, and are they actually going to be able to use it to improve production efficiency at the feedlot level and therefore at the carcass level as well?”
As well, interest from feedlots in implementing management practices based on these findings needs to be gauged. Olson says it may be of interest because measuring chute exit velocity and sorting on that basis doesn’t require further processing.
“It’s something that can be done when cattle come off a truck, more or less, and enter the feed yard.”
While this study included the use of Brahman genetics, Canadian cattle are primarily Bos taurus. However, temperament can be compared between Continental and British cattle in Canada, and could serve as a method for sorting feeder cattle. But it may not have the same impact in a Canadian feedlot.
“Over the years all of the Continental breeds have done, I think, a very good job of bringing down their average temperament, so I’m not sure that the differential in temperament in Canada is going to be as severe as the temperament differential at a feedlot in south Texas,” he says. “So here we may want to do more of an animal-by-animal evaluation.”
This could include measuring an animal’s chute exit velocity as part of the arrival procedures and comparing it to the feedlot’s average, using that to sort based on temperament regardless of breed.
“In a Canadian context I think it’s a little bit of a different story because we don’t have that variation in breed, and I don’t believe that we have as much variation in breed temperament as we anecdotally think there is. But I think it’s still something that we can use to improve the management of cattle at the feedlot level.”