Last week, WLJ reviewed the first research regarding a novel condition found in some cattle right before slaughter—fatigued cattle syndrome (FCS). The original cause of this syndrome was thought to stem from feeding a beta agonist to feeder cattle, but newer research has proven otherwise.
FCS is an exhaustion, both physical and physiological, of the energy storage within the muscle, Dan Thomson, Kansas State University professor of production medicine and epidemiology, told WLJ.
Thomson is a leading researcher of FCS and was one of the coauthors on the original research detailing the syndrome in cattle.
“Based on how we handle cattle, how finished they are and environmental temperatures, can lead to an exhaustion—not just a physical exhaustion, but a physiological one of the energy storage within the muscle.”
Thomson describes FCS in another specie: in horses, the condition is known as “Monday morning sickness.” Feeding a horse a high grain diet and not exercising over the weekend can lead to its muscles tying up that following Monday.
The cause behind FCS
“For the last 30 years, we’ve increased our outweights in cattle pretty significantly,” Thomson said. “The combination of that, transporting cattle during summertime in afternoon shipping, and getting animals out of their pen to the truck can exhaust the animals.”
This overworking can cause an increase in lactate buildup in blood, as well as creatine kinase. Lactic acid is produced in muscles and builds up during intense exercise, which can cause sore muscles. Creatine kinase is an enzyme that will leak out of damaged muscles, indicating muscle tissue injury. Upon unloading at a packing plant, cattle muscles can tie up and show clinical signs of FCS.
Many people in the industry may not be familiar with FCS. There are a few reasons for this. First, it tends to creep up seasonally, in the summertime, when the weather is the warmest. Perhaps the largest factor is the syndrome isn’t something typically seen at a feedlot setting: It isn’t until an animal is unloaded at the packing plant that clinical signs are shown.
“We’ve looked at the prevalence, which is pretty low, and the three biggest risk factors are increased outweights, heat stress, and aggressive cattle handling,” Thomson said.
“When this first happened, we blamed beta agonists for creating this issue,” Thomson said, “but we did studies simulating aggressive handling versus low stress handling in feedyards. We’ve looked at lactate and creatine kinase levels, and physiological responses to stress, and found that we can create FCS in animals that are not on a beta agonist, and we can prevent FCS through low-stress handling in cattle on or off beta agonists.”
Aggressive handling doesn’t necessarily mean yelling. It more refers to the speed cattle are moved. Cattle that are being walked and are following a lead rider will walk an 18-minute mile. In contrast, cattle that are trotted will run a six-and-a-half-minute mile.
“Anybody that’s gone out to run a six-minute mile versus walking an 18-minute mile knows there’s a huge difference,” Thomson said. “It just doesn’t look like it when these cattle are trotting because they’re big and they can move.”
Thomson equates cattle in a feedyard for six months to a person staying in a hotel with room service for a similar amount of time.
“Imagine if you were in a hotel room and provided room service for 180 days, all you could eat, and every day someone was coming in and checking on you every so often,” Thomson said. “After 180 days of being in that hotel room and eating fine dining, someone comes in at 4 a.m., flips on the lights and chases you out of the room. Then makes you run a six-and-a-half-minute mile.
“It’s important for us to treat these animals with care. We sit there and feed them for six months and we can ruin all that hard work in the last five minutes.”
Prevention
“It comes down to how animals are handled at the feedyard and making adjustments at the packing plant,” Thomson said.
Combating summer heat stress by having shade over loadout and holding pens can make a vast difference. When moving cattle from pen to pen, have experienced people go out to move cattle. Acclimate cattle to entering and exiting the pen when they first arrive in order to accustom them to moving slowly, so shipping day won’t come as much of a shock. Having a lead rider in front to set the pace will also keep cattle from moving too quickly.
Transporters also play a role by loading trucks properly and in a calm matter. Taking direct routes and not stopping unless necessary will keep cattle cool from airflow.
Packing plants have a responsibility to have comfortable flooring and shade in holding pens, and an efficient system to get cattle off sitting trucks. Providing a cool and comfortable place for cattle to wait will also help with preventing muscles tying up.
“At the end of the day, there really has to be communication between the packer and the feedlot,” Thomson said. “It can be pretty detrimental to your pocketbook. If you have a slow mover at the packing plant, those animals wind up getting condemned and either euthanized or sent back to feedyard.”
Every segment of the industry is involved in keeping FCS at bay.
“It’s a simple syndrome, but it has a huge impact on animal welfare and a huge impact on how our industry is perceived in treating its animals,” Thomson said. “It also shows the importance of the segments of the industry working together.” — Anna Miller, WLJ editor
