When working cattle, keep your insulated container in the shade, with the lid on it to minimize sunlight and dust contamination.

“If something happens to delay your work, don’t just put your syringe down and forget about it,” Miesner says. “Even a short time in the sun can inactivate an MLV vaccine,” he says.

Miesner says he’s seen producers configure coolers with holes in them, “like little holsters for syringe barrels – and ice bags inside the coolers –where you can stick the syringe into those holes.” The barrel fits all the way in, with only the handle sticking out, he says. This keeps the syringe contents cool and out of the sun when you aren’t using it, without having to continually open the lid of the cooler. All you have to do is grab the handle of the syringe.

Similarly to vaccine needing to stay cool in hot weather, it must be protected from freezing in cold weather.

“If, in cold weather, you set the syringe down (instead of putting it back in the cooler) while you do something else, and it freezes, this will damage the vaccine. Thawing it won’t resolve the problem because the freeze-thaw process will be detrimental,” Miesner says. If the needle freezes up between animals, a jar of warm water to immerse the needle works well, but don’t allow the vaccine to be continually freezing and thawing.

“Always use a new, sterile needle for refilling syringes. Don’t put a dirty needle into a new bottle, especially when mixing an MLV product. The product should always be going out the needle, and nothing coming back through unless it’s a new needle, or it will contaminate the contents of your syringe,” Miesner says.

Size matters

When using MLVs that must be reconstituted, only mix the amount you’ll use in one hour. “Producers or feedlot crews working a lot of cattle might use several bottles of vaccine at a time, but don’t mix them all up at once,” he says.

“Meanwhile, cow-calf producers who are working cows and palpating as well as vaccinating, while also maybe taking time to do some dehorning or other tasks, would be wise to buy vaccine in small bottles. That way, you can use up each one within that hour window. If it’s mixed too long, it can lose effectiveness,” Miesner adds.

In many situations, 10-dose vials are preferable to 50-dose vials. Though the larger size may be more economical, you won’t save money if the vaccine is compromised by the time you’re using the last portion of that big bottle. Even a killed product can eventually get too warm if it’s taken from the cooler periodically to refill the syringe.

If you know you’ll be out at the chute all day, use an insulated container with an ice pack, and take only the amount of vaccine you might use during the first few hours, Miesner says. When that runs out, get more from your refrigerator – and new ice packs.

“Discard any leftover doses; they won’t keep,” Chase says. “Killed vaccines may be good for another day if they were kept cool, but always try to buy bottle sizes you’ll be using up quickly. I’ve seen people buy clostridial vaccine for young calves in 50-dose bottles and take out just a few doses at a time. But the more times you puncture the lid, the more chance of contamination; soon, there’s such a big hole that vaccine may come running out,” Chase says.

When working cattle and giving more than one vaccine, make sure you don’t grab the wrong syringe when refilling.

“Color-code syringes with tape or label them,” Miesner says. “If you were to draw another kind of vaccine into the wrong syringe, it could inactivate that whole load or make it less effective.” Putting an MLV product into a syringe that previously held your eight-way clostridial killed vaccine, for instance, could inactivate the MLV.

“Even worse would be to grab a syringe you’d used for giving an antibiotic, and loading it with vaccine. Things sometimes get crazy when you’re in a hurry or distracted, and I’ve seen things like that happen. The sad thing is tht a person often doesn’t realize it until it’s too late,” he says.