Some of the biggest health challenges in finishing cattle can be minimized or even prevented long before the animals arrive at the feedlot.
In fact, calves can be set on a path to better health before birth, according to veterinarian Dr. Greg Dimmers of Metzger Veterinary Services in Linwood, Ont., to help address what he says are the biggest feedlot health issues: bovine respiratory disease (BRD), lameness and metabolic diseases.
“BRD is by far the most expensive and prevalent problem, but we have a lot of opportunity to make a difference in how we manage cattle,” he said during a presentation at the 2020 Beef Symposium at the University of Guelph. “Three out of every four sick cattle in the feedlot have pneumonia and one in every two deaths is as a result of pneumonia.”
It’s estimated that every case of BRD costs over $100 in treatment, results in reduced performance or, potentially, mortality. Although the industry has done a good job of creating better vaccines and managing the disease, Dimmers said almost no progress has been made in reducing prevalence or cost in the feedlot.
Although historically more associated with dairy cattle, hairy heel wart and strawberry foot rot are increasingly causing lameness problems in the feedlot, too. Some of that can be related to feeding Holstein-cross steers or backgrounding heifers, but regardless of origin, it’s a challenging — and costly — problem to manage in the feedlot environment.
“This disease takes a long time to develop; when we see sores, they’ve already been developing for three to five months,” he says. “So that’s a welfare issue but also a cost; average daily gain is half a pound less in a lame animal than a comparable, non-lame pen mate over the feeding period.”
Start with the cow
When it comes to calf health, much of the beef industry is focused on the 30 to 60 days around weaning when calves are separated from their mothers, vaccinated, castrated, transported, dehorned and commingled — all in all, a very stressful period for these young animals.
Much less attention is paid to two months before a calf is born, but that’s where the biggest impact could be made.
“Starting at 60 days before birth, there is a lot of opportunity to do the right thing or make improvements to what we do now,” Dimmers says. “From the moment the calf is conceived, the genetics are locked in, but we can manipulate the environment of the cow and change how the genes are expressed when the calf is born.”
The nutrition, heat or cold stress, and mineral deficiencies the cow is exposed to will influence the future health and performance of her calf through a process called pre-natal programming or imprinting. The organs are developed during the first trimester, followed by the immune system in the second and the calf’s muscles and skeleton in the third.
“If we impact the environment of the cow during these times, we can have an interesting impact on those systems long into the life of that calf,” he notes.
Dimmers believes a significant opportunity at the cow-calf level lies with doing a better job of managing variation in weight, immunity, sex, frame size and average daily gain.
Testing feed and feeding minerals will help with this. According to western Canadian and Ontario cow-calf surveys, 66 per cent of western cow-calf producers test their feed, whereas 66 per cent of Ontario cow-calf producers never test feed.
“This is one that really stands out to me when you look at differences in what they’re doing in the West and what we’re doing (in Ontario),” he says, adding this results in deficient or over- or underweight cattle.
Mineral deficiencies can lead to weak-born or deformed calves, more severe pneumonia and scours, poorly functioning immune systems, and poor breed-back and conception. A 21-day delay when a cow doesn’t catch until the second cycle means $90 of lost weight at weaning, Dimmers says.
Another strategy is better management of the breeding season. Tighter calving periods mean easier management, less scours, easier processing and less variability on weight ranges. Maintaining a 63-day breeding period by not keeping the bull in the herd year-round keeps cows on a consistent annual cycle. It also avoids potential welfare issues with early maturing heifers being bred too early; according to Dimmers, feedlots aren’t set up to deal with calves and calving, and most calving feedlot heifers don’t survive.
“Farmers say it’s hard to manage bulls and keep them separate from cows, but there’s an opportunity here to reduce variation of cattle coming out of a single herd (by pulling the bull),” he says.
Starting the calf
Another big opportunity lies with vaccinating cows and calves. In Ontario, that applies particularly to two essential viruses: infectious bovine rhinotracheitis (IBR) and bovine viral diarrhea (BVD). Dimmers noted the IBR vaccine can reduce abortions by 60 per cent, and the BVD vaccine can increase the pregnancy rate by five per cent while reducing abortions by 45 per cent.
Vaccinating all animals in a herd against BVD costs approximately $9 per cow. A herd that is not vaccinated with a persistently infected calf can result in lost revenue of $60 per cow. It’s estimated that every animal in a feedlot that is exposed to one that is persistently infected will cost $80 per head.
“We should be taking a closer look at how we are vaccinating,” he said. “If you really truly have a closed herd, you can be free of BVD and IBR, but I don’t think I’ve ever seen a truly closed herd.”
Proper vaccine handling and storage will also have an impact on animal health. According to Dimmers, a study of temperature sensors in vaccine fridges in both vet clinics and on-farm showed that only one quarter were within the desired temperature range more than 95 per cent of the time. The longer a vaccine is out of its ideal temperature, the higher the likelihood it will sustain damage that will decrease its effectiveness.
Live vaccines should be used within one hour of mixing to ensure every animal gets a consistently good dose. Don’t put a dirty needle back into the vaccine bottle, and if using implants, a good rule of thumb is to change the needle whenever the implant gun is changed.
A good live, five-way vaccine should be given to every single calf as a robust preventive program, he advises, although the key is choosing a vaccination program suited to the operation and the type of cattle going into the feedlot.
As well, bulls, animals with horns and pregnant heifers are at a much higher risk of having health issues in the feedlot depending on how they are managed, so having a protocol for animals that fall outside of regular feedlot parameters is important.
Roadblocks to progress
“Economics remains the number one driver behind health-related decisions, but we have to keep in mind who our customers are,” he says. “For cow-calf producers, the feedlot is your customer, so you need to pay attention to what they’re asking for.”
Regardless of health outcomes, though, Dimmers encourages all producers to do three things:
- Be critical of the things they do, such as vaccination, culling decisions and feeding programs.
- Be on the hunt for new ideas, products, and innovation.
- Be willing to adapt. c
Originally from a dairy and beef farm in southern Ontario, Lilian Schaer is a freelance agricultural journalist and communications professional based near Guelph, Ont. You can follow her on Twitter @foodandfarming.