DULUTH, Georgia (March 1, 2019) —You can’t always know the pregnancy status of every animal or have the time to separate pregnant cows from the herd. But with killed vaccines, you can usually vaccinate any animal — regardless of age or production stage — with confidence.
Killed vs. modified-live-virus vaccines
Vaccines generally fall into two categories: modified-live virus (MLV) and killed virus. Both types of vaccines contain a form of the viruses that help “prime” the immune system, so the next time the animal comes in contact with those organisms, it will recognize them and mount an immune response.
MLV vaccines contain live viruses that have been attenuated, or weakened, so they usually can’t cause disease in the animal. However, in rare cases, an animal might develop disease. Some MLV vaccines, if administered to pregnant cows, can lead to abortion.
Killed vaccines, on the other hand, contain viruses that have been killed, or chemically inactivated. While they cannot cause disease or abortion in an animal, they do require adjuvants or special vaccine additives that help enhance the immune response.
Any age, any stage
The biggest advantage of using a killed vaccine is it can generally be administered to animals of any age at any stage of production — even pregnant and immunocompromised animals.
“If you purchased a cow, and you’re not sure if she’s pregnant or not, or you don’t know her vaccine history, killed vaccines are very safe,” asserted Peggy Thompson, DVM, Boehringer Ingelheim.
“They’re also a good choice when you’re not sure which vaccines your own cattle have had in the past,” she added. With killed vaccines, you have the flexibility to vaccinate an entire herd without separating out the pregnant animals.
Boosting calf immunity
Vaccinating a pregnant cow also helps to protect her future calf and to make antibodies to pass onto the calf. “When we vaccinate a pregnant cow, we’re really trying to enhance the colostrum that she’s going to make for that calf,” said Dr. Thompson.
Fitting killed vaccines into your protocol
It’s important to work with your veterinarian to develop the best vaccine protocol tailored to your operation. At the same time, it’s essential to read and follow label directions. “Three to four weeks after killed vaccines are first administered to an animal, a booster vaccine is usually required,” noted Thompson. “That booster is necessary if producers want optimum immune protection for their animals.”
Choosing the right killed vaccine
“Producers should look for avaccine that’s easy to use,” Thompson advised. “Vaccines that can be administered subcutaneously in low doses in the neck can help support Beef Quality Assurance standards.” Good vaccines also have research and data to support their efficacy.
“In the industry today, there’s been a lot more interest in killed vaccines as they relate to animal safety,” Dr. Thompson concluded. “We’re learning they have more of a place in operations than what we may have thought in the past.”