Beef market turmoil and weather challenges will make Kansas and Oklahoma’s stocker industry a high-stakes game in 2020. With reining in costs to save profit margins a more important strategy than ever before, producers are searching for ways to reduce overhead without sacrificing cattle health and nutrition.
For cattlemen receiving stocker cattle, John Richeson a professor of animal science at West Texas A&M University, recommended some chute-side prospective shifts.
“Metaphylaxis is proven and very, very effective —it's really the only thing we can do at the chute that truly makes an impact on cattle health,” Richeson said. “Metaphylaxis can reduce BRD, morbidity and mortality by about half on average and improve average daily gain.”
Metaphylaxis is essentially identifying a disease, in this case bovine respiratory disease, and instead of treating only the affected animal, treating the whole group to avoid the spread of sickness. BRD is one of the biggest challenges stocker producers face, especially when receiving high risk cattle because of the disease’s association with trauma of cross-country travel.
“To me, this diseases, it's a disease of stress,” Richeson said. “The pathogens are pretty ubiquitous and it's really a stress-induced immune suppression.”
When using true metaphylaxis — treating every animal straight off the truck — there is potential to treat healthy animals that receive no benefit from the often-pricy injections. In fact, in metaphylaxis strategies, only 20 out of every 100 cattle treated are directly benefiting from treatment.
Using a targeted metaphylaxis strategy would narrow in on treatment for just the 20 most-at-risk cattle in this scenario and provide treatment for only those 20 on arrival. The trick is finding rapid, repeatable, accurate ways to identify the highest risk animals in the chaos of unloading.
Richeson identified five measurable markers for high-risk cattle in his research at West Texas A&M.
Bulls vs. Steers
While castration is a fairly simple procedure for cattle producers, castrating cattle on arrival can have some significant health risks associated.
“If you’re purchasing cattle at market, stocker calves that arrive as bulls are 3.32 times more likely to get BRD than calves that arrive as steers,” Richeson said. “We could target our metaphylaxis based on bulls versus steers, but the problem with that is that 80 percent of the loads I buy are bulls, so there needs to be more differentiation.”
Richeson said castration predisposes calves to BRD because the pain an inflammation associated with the procedure taxes the immune system. For a disease that slips in on the more immunosuppressed animals, castration only opens up more opportunity for the disease to spread.
It’s a well-known strategy for cattle buyers to target calves with ear tags as an indicator of extra attention at the cow-calf level, either for calves with bunk training or more access to vaccines. For producers at the stocker level, cattle without existing ear tags may be better served by on-arrival treatments for BRD.
“An ear tag on a calf tells us that calf has probably been through the chutes at least one time on their ranch of origin,” Richeson said. “They’re more likely to have had at least one round of vaccinations and potentially have been on a better nutrition program.”
While Richeson was quick to say that an ear tag has no actual health benefits for the animals; it has served as a measurable indicator of health during his research.
“For the cattle we collected data on, the calves initial body weight was about the same, but if the animals had an ear tag they gained significantly more weight and as a group had significantly less morbidity,” Richeson said.
Relative Body Weight
Lightweight or thin animals consistently are more at risk for morbidity than heavier animals, however, identifying what proportion of the cattle arriving are considered “light” weight is critical for precise targeted metaphylaxis.
“Research that we've done and others have done shows that within a truck load the lightest 25 percent of the animals within a truckload have a higher morbidity rate than the heaviest animals within that same load,” Richeson said.
With the right technology, digital scales could be used to quickly assess whether the animal being weighed is in the lower 25 percent and help make strategic metaphylaxis decisions without a lot of chute-side number crunching, Richeson said.
“Rectal temperature is something we have used for a long time to determine inflammation or cow morbidity,” Richeson said.
If rectal temperatures are already being taken chute-side, cattle with temperatures of 103 degrees or higher would be at higher risk for BRD and would be good candidates for targeted metaphylaxis.
In a study conducted in the 1990s, 42 percent of cattle had a higher temperature on arrival and that group saw increased morbidity. Today, rectal temperatures are a less accurate metric for sickness because of increased antimicrobial resistance, Richeson said.
“We can measure things in the blood that tell us if an animal may be at greater risk for BRD — things like haptoglobin which is an acute phase protein or serum chemistry variables like non-esterified fatty acids,” Richeson said.
Haptoglobin shows a big response in inflammation but the response rapidly comes back down, making it a hard marker to catch over the length of time it takes to unload and assess a truck load of cattle. NEFA concentrations are often used as markers in other cattle systems, but are more targeted toward cattle with nutritional deficiencies.
“When high risk cattle come in, their NEFA concentration is very high and then within two weeks it normalizes, most likely because they haven’t had access to food or water at some points during hauling,” Richeson said. “Dairies use NEFA concentrations a lot to identify cows in a negative energy balance.”
The most successful bio-assisted marker in Richeson’s research has been cattle’s leukocyte profiles. With BRD being a very immunity –tied disease, white blood cell counts are a natural way to target at-risk animals.
While drawing blood on each animal chute-side can be a hassle, Richeson has tested samples in the field with results in less than a minute.
“We've been drawing a quick sample of blood and using a machine that assesses the leukocyte counts of animals on an individual basis within about 30 seconds to help give us an indication of health risk of individual,” Richeson said.
The machine can give a red or green light to tell producers to treat or not to treat based on the leukocyte profile. The technology is expensive but highly accurate and for producers receiving large volumes of cattle, it could save a significant amount of money in medicine costs.
Richeson said that even without the use of high-tech identifiers, focusing on easily identifiable markers like cattle weight, intact bulls and existing ear tags can be a simple way to reduce costs while maintaining herd health protocols.