First Colostrum, Then Vaccinations

In his presentation during the Professional Dairy Producers of Wisconsin (PDPW) Annual Business Conference, Chase explained the development of a calf’s immune system. Keep in mind, half of the calf’s genes come from the bull. That means that the cow’s body doesn’t recognize those genes and wants to reject them. To prevent abortion, the placenta suppresses the immune system and response to keep the calf safe. That means the calf is “bathed” in this immunity suppressant. As a result, the calf should have absolutely no antibodies when it is born.

Colostrum contains these vital antibodies, referred to as IgGs, to stimulate and build the calf’s immune system. Colostrum also contains many anti-inflammatory hormones that regulate the speed at which the immune system reacts to the IgGs. If that didn’t happen, the calf’s body would be “overloaded” and wouldn’t know which antibody to focus on first. This natural system is what makes colostrum management so important.

Chase said, “In general, we vaccinate calves too much and too soon.”

He said that unless a herd struggles with bovine viral diarrhea (BVD) persistently infected (PI) calves, better colostrum management means less of a need to vaccinate.  When it does come time to vaccinate, Chase said it’s important to understand how and why a vaccine works. He used intranasal vaccines as an example. He said people sometimes think an intranasal vaccine isn’t working because they didn’t see a response in the bloodstream when they took the sample. However, Chase pointed out that they shouldn’t see a response because that’s not where the vaccine was intended to act. Rather, an intranasal vaccine should act on mucous cells instead because they’re intended to target pathogens that would enter the calf’s body through the nose.

Chase also warned against vaccinating too frequently. He said that it typically takes 17 to 21 days for a calf’s body to develop a strong immune response. That’s because its immune system isn’t perfect and does “turn out some dud cells.”  The calf’s body needs a few days to separate these cells from the good and get rid of them. He said it’s a common misconception that “if you don’t get a booster early, you’ve wasted the first shot.”  But that’s not true either. The calf’s body needs adequate time to fully respond to the first dose of the vaccine.

“I prefer to wait a little,” Chase said. “It’s better to give it time.”