Weaning: A Critical Part of Antimicrobial Stewardship By Dr. Lee Jones, M.S., D.V.M., Associate Professor, Dept. of Population Health, UGA

Weaning:

A Critical Part of Antimicrobial Stewardship

By Dr. Lee Jones, MS, DVM, Associate Professor, Department of Population Health, UGA

As cow/calf producers, we might think that antimicrobial stewardship doesn’t really affect me on my farm or ranch. In reality, though, that’s where it starts. If we want to reduce antimicrobial resistance as an industry, we need to reduce antimicrobial use across the board. Eliminating antibiotic use in farm animals isn’t reality. The fact is that they are essential tools of good animal husbandry and animal welfare in controlling and treating diseases in animals. The most common threat to animal welfare is disease. Disease prevention is not only good welfare; it is also good business. Disease costs the cattle industry billions in lost production, treatment expense, and animal death loss.

So what’s the cow/calf producer’s response?

I was talking to a feed yard expert at an NCBA meeting in Denver a few years ago, and he told me, “Lee, if we could just get producers to wean the calves – that would reduce disease during the receiving period by half.”

That’s the answer? Weaning? Could it really be that simple?

In short, the answer is yes, it really is that simple. But how does weaning reduce disease and thereby reduce antimicrobial use?

Weaning isn’t just separating calves from their mommas. Instead, weaning is a process that helps calves thrive during the process. It’s preconditioning, which starts before weaning and typically lasts for 30-60 days or longer after separation, depending on the farm goals.

Weaning is the first step in a series of stressful events for most calves sold in the U.S. According to USDA NAHMS data, the typical Georgia beef calf is separated right off the cow, hasn’t been vaccinated or dewormed (and most males aren’t castrated), delivered to an auction market, commingled with other calves, sold at auction, sorted yet again into uniform truckload groups at yet another facility and transported to a processing location. Just like many youngsters get sick the first week of kindergarten, many of these high-risk, light-weight calves will get sick and require antimicrobial treatment.

The stress of weaning can be reduced by fence-line weaning or two-step weaning. Two-step weaning uses a device that attaches to the calf’s nose to keep the calf from nursing but still stays with the cow in the pasture – sort of like a weaning prep. Fence-line weaning is simply separating cows and calves using a sturdy fence or electric fence. Cows and calves can graze close by each other but not contact each other during the 3-5 days they are being weaned. Farmers report that these methods reduce stress, weight loss and calf sickness during and following the weaning process, compared to abrupt removal and separation of the calf and the cow.

Good nutrition during this process is essential. The calf has been accustomed to a diet of green grass and milk for several months. While the calf can still graze,

depending on the time of year and pasture conditions, some supplement helps the calf transition to a different diet. Providing a well-balanced, highly digestible diet – including adequate protein and energy (a diet too high in carbs can be as bad as too low) – is important to help calves continue to gain weight in the weaning period. This is a good time to introduce calves to feed bunks and water troughs if they aren’t already familiar with them.

Vaccination and deworming are definitely part of the weaning program. Ideally, the bull calves were castrated before 4 months or less than 200 pounds because castrating later increases negative side-effects. If calves haven’t received a modified live viral vaccine before weaning, after they are removed from the cow is a good time to administer an MLV. Weaning is a good time to booster the clostridial vaccine (7-way blackleg), too. Other vaccines may depend on the marketing program or past history of the ranch. Oral or injectable dewormers are beneficial as well at this time too. Consult with your veterinarian to design an effective weaning health program.

Weaning reduces shrink when calves are transported and sold. Shrink is the weight loss following an extended stressful event. The amount of shrink depends on many factors. Low-stress handling and preparation helps prevent or minimize weight loss in these calves. Calves that have experienced significant shrink are dehydrated and at increased risk of disease. Severe shrink can take up to 30 days for a calf to recover, at which time the animal won’t be performing optimally and is at higher risk for respiratory disease.

“I can’t get paid to do that.” While that may have been true in the past, premiums are available for a health program. Or some calves are discounted for no health program. Calves that go through a documented weaning and health program are worth more than a calf that is just sold through the sale barn. Getting paid for a weaning program will require some research and planning, but premiums are worthwhile – but it’s important to keep track of the expenses of a weaning program.

It is essential to have the health program properly recorded and have it available when marketing calves. Many Georgia auctions report steers separate from bulls, and there is often a $25-30/cwt premium for steers over bulls sold through weekly auctions (checked for July 27, 2022). That is a $125-150 per head premium just for castrating bull calves!

We need to be honest about the risks to the calf’s health involved in every step of the production chain if we ever want to actually reduce the effects on calf health and subsequent need for antibiotics to control or treat disease. Preparation of the calf during the market transition period has been shown to reduce disease and improve production. It’s good for the calf, it’s good for the industry – and it’s just good stewardship.

This article is updated from the October 2021 article.