Respiratory infection season is here for most animals and people. Generally, this is because the temperature swings and moisture increases, which are major stress factors. Stress causes the body to drop its defenses and become more susceptible to diseases in the environment. With a susceptible immune system, now we start getting a cough or snotty nose. As it progresses, the infection moves down the tract to the lungs and into full blown pneumonia. And while the infection is doing this in one calf, the coughing and snot is traveling through the air infecting others near this calf.
A sale barn is like a school. When school starts students are brought into small rooms and co-mingled. We are co-mingling germs from across the school district or world. The stress of going back to school drops their immune system defenses and somewhere around three to four weeks into school here comes the infection. Sounds kind of like a sale barn or stocker yard, doesn’t it?
We bring our calves to the sale barn to be sold. They come from all over the area. They are stressed and mixed with other calves from who knows where. They are worked through a sale ring and moved to buyers pens (school rooms). Now they wait for their truck to take them to their new home (i.e. school bus). At their new home they are put into a pen, offered water, hay and feed. But, they have never seen it offered in that way. So, they are scared, stressed and trying to make new friends in their new home.
Then they are put through a processing chute, vaccinated, dewormed, identified, castrated, dehorned and whatever else. All of this adds more stressors to the calves’ system. Then the temperatures change and we get cold and wet. And here comes a cough or snotty nose. This can result in an infection rate as high as 70-90 percent and a death loss as high as 2-10 percent.
The best way to avoid this type of infection rate is to pre-wean vaccinate and process calves. If you have ever watched calves after we work them through a chute and process them, they run out of the chute back to momma and pretty soon they nurse. Now when that calf nurses, all of the stress just flies away. He is safe and back to normal. Then when we wean calves and all we do is use booster vaccinations, we have the least amount of artificial stress on them that we can. Also at the sale barn, as you walk down the aisle where these calves are housed until the sale, they are just sitting there quietly. They are not balling there heads off like normal unweaned calves.
Dr. Tim E. O’Neill, DVM owns Country Veterinary Service in Farmington, Ark.
