The province and local veterinarians want beef producers to stop shooting blind when treating calfhood diarrhea.
Dr. Cathy Clemence of the Russell and District Veterinary Clinic is urging producers to bring a manure sample to their vet before placing bets on an uncertain treatment plan.
“Typically the producer tends to (think), ‘The calf has scours. I’ll treat it with antibiotics and fluids and see if it gets over it,’ and the calf doesn’t come in for three days and then it’s flat out and dehydrated to death,” she said. “They’ll do that a couple of times and then they finally get frustrated because what they’re doing isn’t working, and then they want us to investigate.”
The province highlighted the issue during its annual Beef and Forage Day seminars late January. Diarrhea can have multiple causes, the province pointed out, and a producer will be wasting valuable time and resources treating for a bacterial infection if the problem is caused by a virus or parasite instead.
The most recent pathology review by Winnipeg’s Veterinary Diagnostic Services Laboratory found most calf diarrhea cases were due to parasites like cryptosporidium or viruses like the rotavirus or coronavirus.
Clemence estimated the cost of a manure test at around $100.
“But if you bring a manure sample and we find that you’ve got rota- and coronavirus going on in the first week and we start using Calf-Guard (vaccine), the $100 could have saved you $1,000,” she said.
Producers are often reluctant to spend the money on a test, Dr. Keri Hudson Reykdal of Ashern acknowledged, and often do not come to her until calf losses are mounting.
“We need to be identifying how old they are. Is it a viral? Is it a bacterial?” she said. “In most cases, scours is viral and so throwing antibiotics at them is not doing anything.”
Hydration, including a trip to the vet for intravenous fluids if they get too weak, is much more critical in those cases, she said, along with a vaccination program.
“First and foremost, I think that it’s really important that the cow herd is vaccinated against scours,” she said. “That’s your first step in preventive management.”
The Interlake vet discounted arguments around vaccination efficacy. The products do work, she said, but added that some production practices may make some level of scours inevitable.
“If it’s Manitoba and they’re confined to pens where you’re not able to spread them out, then yes, you’re going to get some scours anyway, regardless of whether you vaccinated or not, but your vaccines are going to prevent your really disastrous outbreaks.”
Producers calving in the barn may also want to watch their building temperature, she noted. A warm, humid environment is friendly to those pathogens, and both Clemence and Hudson Reykdal argued that it is better for a barn to be too cold than too warm.
Diagnostics take time, Clemence said, and a late start to the search often means that the problem is not identified in time to manage the issue properly.
“Their calving’s done the end of April and they come in the week before calving’s done and say, ‘You know, I’ve lost 10 calves and we need to do something,’ and by then it’s too late because the number of newborn calves that are coming are few and you’re not going to get to the bottom (of it),” she said.
Scours and diarrhea were among the top causes of calf death between 2014-17, outside of those linked to calving difficulties, according to the Western Canadian Cow-Calf Survey. It was linked to 12.8 per cent of calf losses from heifers and 8.4 per cent of those from cows — compared to respiratory diseases, which killed 10.6 per cent of the losses from heifers and 16.3 per cent of those losses noted from cows. Just over 16 per cent of calf losses from heifers and just under 23 per cent of calf losses from cows were from unknown causes.
Antibiotic regulation has been a sore spot for producers. As of December 2018, producers have been required to have a prescription before buying most livestock antibiotics, including some treatments for scours. The change was part of efforts to fight antimicrobial resistance in humans, while many producers complained that the new rules made running their business more difficult.
At the same time, Clemence said, she commonly saw producers reaching for antibiotics for calfhood diarrhea before getting a diagnosis, only to have the treatment fall flat.
The recent rules around prescriptions and antibiotics may change that landscape, although both Clemence and Hudson Reykdal doubt it.
“For good producers, it hasn’t really changed,” Hudson Reykdal said, noting that those producers are consulting their veterinarians anyway. “It’s always a matter of convincing people that it’s important to test. A lot of times we do know that it’s probably viral and that antibiotics aren’t going to work, that it’s going to be more of a management situation anyway.”