Ask The Vet

Prevent Future Losses To Scours

Image by Jim Patrico

Q: We had a very bad cold, wet snap with lots of snow, ice and rain right in the middle of calving season. Several calves started scouring, and we treated them with scour boluses and penicillin. We lost four of them. We have not had any more cases since, but we’d like to know what we can do to prevent this in the future.

A: There are so many potential causes when it comes to scours, you really need to get your veterinarian involved. A good history of what happened leading up to this is going to be very important. Some key information would include age of the calves, age of the dams, body conditions, available feed, available minerals and whether cows had been vaccinated and dewormed.

You note this started when bad weather moved in. The cold, wet conditions you describe can sometimes keep calves from getting up and nursing quickly. That can mean they don’t get enough colostrum those first few critical hours of life. Also, muddy, nasty conditions increase the chances disease will spread. They also make maintaining a normal body temperature difficult at best.

If cows are thin, or lacking in balanced nutrition including minerals, colostrum quality may suffer. All of these things can work together to increase the potential for sick calves.

An accurate diagnosis is the first step in knowing how to treat calves and prevent future outbreaks. Calf scours can be caused by several different viruses, bacteria and parasites. Antibiotics have no effect on viruses or parasites; they only help if the bacteria involved is susceptible. Just as importantly, antibiotics may kill good bacteria and make the situation worse. The decision on whether, when and what antibiotics to use must be made in consultation with your herd veterinarian.

As you discuss this with your veterinarian, ask for a review of your overall herd-health program. If the situation recurs, act fast to get a diagnosis and a treatment plan under way.

Q: I had a couple of calves that would not go through the gate when we were rotating pastures. All the rest of the herd would go through, but they would get to the gate and just stop, and then run off. We finally took them through another gate. We have never had this happen before. I know young calves can be hard to handle, but these just acted very strange. Any ideas on why?

A: Calves, especially when they get old enough to become “independent of mama,” can make herding cattle difficult at best. The rules often just don’t seem to apply to them--kind of like teenagers.

While I can’t tell you what those calves were thinking, I’m wondering if the fence that gate connects to is electric. If so, consider the possibility of stray voltage.

Use your digital voltmeter to check the ground for stray voltage. If you find any, check connections, underground wire and/or the line for any shorts. Make sure you have adequate, properly installed ground rods. If there is nothing obvious, call the company that made your charger, or talk to the folks who sold it to you for help in troubleshooting.

Stray voltage is a more common problem than many farmers realize. It often arises from the electrical supply and wiring around barns, water troughs and lines, and feeding areas. To some degree, it is always present at low levels that don’t cause problems. But, if livestock are behaving abnormally for no apparent reason, it would be one of the first things I’d check.


Longtime horse owner Bill Bagliani, with horse farms in Raleigh, North Carolina, and Ireland’s County Galway wrote to weigh in on the question of whether it’s safe to feed horses haylage. Here’s what he says:

“When I first brought horses to Ireland, we had a lot of problems with coughs. It turned out to be a fine mold on the hay, which is almost not visible. Ireland is so damp that it is almost impossible to dry local hay properly, hence the coughs.

“After working with a lot of locals and vets, I found that many farmers were feeding haylage. I was concerned, so I tried a small amount on a few horses and, having no problems, increased it till all horses were on haylage with no problems. This has been what we feed for the last 20 years.

“We have a barn with a second floor, so we hoist a bale … and spread it out and turn it once to let it dry (this is after it was allowed to ferment for at least three months). The haylage will typically last for two years if you patch any holes [in the wrap].”

Please contact your veterinarian for questions pertaining to the health of your herd. Every operation is unique, and the information in this column does not pertain to all situations. This is not intended as medical advice, but is purely for informational purposes.

Write Dr. Ken McMillan at Ask The Vet, 2204 Lakeshore Dr., Suite 415, Birmingham, AL 35209, or email


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