Lots to learn about mid-feeding period morbidity

The beef supply chain has many aspects, but it must start somewhere. Those calves that are going into the initial stages of feeding need to be healthy and strong to perform.

Miles Theurer, research director, Veterinary Research and Consulting Services, LLC, recently presented at the virtual Cattle U and has observed what these cattle do and how the mid-feeding period morbidity in high performing cattle can have an impact. More specifically, he studies the first treatment for bovine respiratory disease occurring after 45 days on feed.

“We looked at what the cow-calf producer in the entire beef industry has been selecting for high performing cattle throughout the years,” Theurer said. “Selecting for these high average daily gain and group feed efficiency and carcass quality, looking at the carcass weights, and then the quality grade standpoint.”

Anecdotally, in his research he’s seen an increase in BRD and later days on feed.

“So, when we see respiratory disease or bovine respiratory disease in the feed yard and most commonly results in antibiotic treatment and throughout all that calf’s life stage. There’s significant resources that’s invested at this stage of production,” he said.

A cow-calf producer is trying to get the calves to a stage in their lives when they are weaned and later backgrounded to get ready to the feed yard. Eventually those calves will reach the end of the production side, and all the resources to get them to that point need to be managed responsibly.

“Any morbidity detracts from the advantages of selecting these superior animals,” Theurer said. “However, there’s no formal studies have been performed evaluating potential causes of morbidity in these higher performing cattle.”

Theurer doesn’t have a clear answer to fix this problem, but he does see ways to help remedy the problem with mid-feeding morbidity. First, one must understand the bovine respiratory disease complex. There’s always three components involved in disease, he said. Those include: pathogen, host and environment.

“If any one of those three becomes out of bounds, that is when the opportunity for disease control can occur,” Theurer said.

Statistics shared

According to U.S. Department of Agriculture data from 1999 to 2011, there has only been a 23.1% increase in feedyard death losses those 12 years.

“A lot of things have changed over the time,” he said. “We’re extending cattle longer days on feed.”

And when looked at from the over all health and health outcomes, advancement is not being made.

“In fact we’re going to opposite way,” Theurer said. “This issue didn’t just occur overnight either. This has been something that’s been moving this direction across the industry for a period of time.”

Cattle are still being asked to produce more and more pounds and this rapid progression is primarily driven by the cow-calf producer with their genetic selections.

“It’s been a remarkable turnaround from the feed yard standpoint, and continues to open more doors and markets for the industry,” Theurer said. “But we’ll need to take some of these into consideration when we think about the physiological capabilities of these cattle today and what we’re asking them.”

Trends

Research has shown that there are historical morbidity patterns when looking at respiratory disease in a feeding period.

“Think about the first 30 to 45 days on feed—get through the bulk of those pulls and then morbidity will subside,” Theurer said. “You will have some tailend fallout from those, but, from the historical pattern, most of that is occurring earlier on into the feeding period.”

The majority of the cattle on feed are predominately healthy, but there are those animals who break down with respiratory disease. Theurer has gathered data on high performing, high-risk populations at a southwest Kansas feedyard where he charted temporal BRD patterns. He chose two similar, yet different groups of cattle.

“So these high risk calves would have all been cattle—based off of subjective risk classifications—and these high performing cattle are categorized by being in top 25% for average daily gain feed conversion and quality grade,” he said. “So really kind of intriguing here about day 45 in these high performing cattle is when we start to see this outbreak of respiratory disease.”

High-risk calves

When compared to their cohorts, the high-risk calves were through the bulk of the morbidity at this point in feeding. In one data set, at day 45 about 33% of the BRD occurred in the high performing cattle, while in the high-risk group that number was closer to 70%.

“Those high performing calves—from an average daily gain and conversion health outcome—are still light years ahead from the high risk calves,” Theurer said. “But there’s still a lot of room for improvements there.”

Those realizations can be a driver of how producers can help prevent some of these morbidity issues or what’s causing them, so they can be further managed at the feedyard if warranted. The appropriate vaccines and medical care help influence health outcomes of the calves. Theurer summarized a data set on calves who received modified live vaccines prior to the feedyard. Some could have received up to four vaccines before coming to the facility.

“(I was) trying to look into this from the vaccine management strategy,” he said. “What’s being done to those calves prior to the feedyard? How’s that setting those cattle up for success or failure?”

The calves who were given only one modified live vaccine prior to the feedyard actually had less BRD treatments compared to those calves that were given it three times.

“So, again emphasizing that more and modified lives are not necessarily better,” he said. “Now there’s still a lot of confounding that goes into this and we tried to account for that from the statistical model by including in the ranch, the cow-calf operation.”

Theurer wasn’t able to look at the timing of when the vaccinations were given, and there wasn’t enough data to split out and look at timing and number of vaccines in the data.

“So, is this a perfect take home solution? No, but it does provide some credence that a lot of this issue going on from the feed yard,” he said. “We’re not going to be able to manage it through a needle. We’re going to need to look at it from a holistic approach from the host and environment side, in order to make advancements.”

Using medicine

Theurer believes there is a time and a place for vaccines and they’re needed for managing the health of the cattle.

“Don’t go taking away from this that vaccines aren’t helpful,” he said. “There is a time and a place for them. However, necessarily more may not always be better.”

From a veterinary practice standpoint, when there’s an opportunity to improve the cattle health, take into consideration the controls in place to determine if it’s the actual pathogen that’s causing the disease.

One of the most recent projects Theurer helped put together with Noble Research Institute was the effect of rate of gain and backgrounding on feedlot BRD. In it researchers put two groups of small calves, 56 head in each and looked at different randomizations over preconditioning for 80 days or preconditioning for 197 days before coming into the yard.

“Lots of confounding in this data set,” he said. “But we’re trying to look at what can those management strategies trying to get some really better pilot data over what’s being done to those cattle priority to coming in to the feed yard to setting up for success or failure here.”

In the group preconditioned for 197 days there was still a 9% cumulative morbidity, with all of the cases occurring after 30 days on feed. Theurer said when he traditionally thinks about the most common instances of respiratory diseases, most often it happens during ration transitions.

“We’re really kind of scratching our head and figure out how can we better make improvements here,” he said.

Theurer, in the data sets, took a lot of serial weights on the cattle in the study, looking at their average daily gain, and did so because he had birth, weaning, yearling and arrival weights, in addition to the weights collected at the feedyard. He went further, and evaluated the average daily gain on the first 30 days on feed—from arrival processing until 30-day weights were done. He found the calves with respiratory disease were on the lower end of the average daily gain spectrum in the first 30 days.

“There’s a lot of our theory and in my hypothesis before looking at this was—were some of these cattle just growing at such a fast rate during this initial feeding phase that that were outgrowing their physical capabilities?” Theurer said. “After putting this data together, kind of switched my thinking around.”

Some of the calves were subclinical for a bit, but for the most part they didn’t see instances of sickness occurring until later on into the feeding period. If they’re not eating, they’re not gaining enough to support growth or immune function during the initial phase.

“Is there a single thing on this, or are there lots of things that go together?” he said. “Short answer is at this point we don’t know, but it’s something that we sure have an interest in further looking at.”

Theurer found unfortunately morbidity and mortality in these high performing cattle is greater than expected, and occurs at later days on feed compared to the high-risk calves.

“Additional research is needed to further evaluate this,” Theurer said. “We don’t have the answers all put together here, and to do this the beef industry must continue to work together up and down the supply chain to better understand the issues and what factors all went into those, so we can make more and more, more improvements throughout the chain.”

Kylene Scott can be reached at 620-227-1804 or [email protected].