A dam’s nutrition will affect her colostrum quality. While it’s common to feed beef cows poorer quality forage, proper supplementation is important to ensure they have enough energy, protein and trace minerals for proper growth/development of the fetus, and production of quality colostrum.

“Vaccination alone won’t solve problems. Some people think the answer is in a bottle, but the immune system doesn’t get a free ride when it comes to nutrition. When you vaccinate, there has to be enough energy, protein and other nutrients for it to work,” Chris Chase, a South Dakota State University DVM, says.

Studies on immune response

Chris Chase, South Dakota State University DVM, is involved in a study in which cows were fed 80% of NRC requirements during gestation. The study’s main purpose is to examine cow nutrition’s effects on muscling/marbling in the calves, but it’s also looking at immune response in the calves.

“If we don’t feed cows properly, not only are we cheating colostrum quality but we could be affecting the growth, development and immune response of that calf for longer than we realized,” he explains.

“Fetal programming in calves includes immune response. For example, in calves infected with bovine viral diarrhea (BVD) in the final trimester, we used to say that the calf’s immune system is working by that point, the infection will be controlled, and the calf will be normal. Now, it’s clear that there’s a negative effect on the immune system once the calf is born.

“The same effect may occur if the cow doesn’t have enough energy in her diet. After the calf is born, you can’t make up for shortages during fetal development,” Chase says.

IBR-BVD vaccines are a must

Cowherds should always be vaccinated against infectious bovine rhinotracheitis (IBR) and bovine viral diarrhea (BVD) – not only to prevent abortion and disease in cows, but to protect the fetus during gestation and the newborn calf via antibodies in colostrum.

James England, a DVM in the University of Idaho’s Caine Veterinary Teaching Center, says many beef herds are vaccinated routinely at the time of pregnancy checking.

“For these herds, I recommend cows be given modified-live viral (MLV) vaccines for respiratory diseases and abortion (BVD-IBR-BRSV vaccination) and clostridial boosters. If cows have already had their two-shot series with scour vaccines, we just booster them once annually at preg-checking.”

If cows are confirmed to have been vaccinated with IBR-BVD previously, he recommends an MLV vaccine at preg-check time. “If we’re unsure, we use the killed vaccine,” he says.

Some of the MLV vaccines that are safe to give to pregnant cows that have already been immunized may cause abortion if you vaccinate cows that have not been immunized previously. 

He suggests producers work with their veterinarian on a herd health program for their situation.

“You also need to revisit your vaccination program every year because there may be some newer forms of vaccines or additional information about them or some better ideas about timing,” England says.

“The goal is to have every cow vaccinated and immunized against IBR-BVD – hopefully, with an MLV vaccine – before she’s bred for the first time as a heifer. After that, she just needs an annual booster, an MLV vaccine once a year.”

Vaccination can’t fix poor management

Vaccination will not compensate for poor management, says Shelie Laflin, Kansas State University clinical associate professor of agricultural practices. “Vaccines can be helpful, but you can never overcome a high pathogen load with vaccination,” she says.

Laflin firmly believes in programs like the Sand Hills Calving System. This is a system in which the calving herd is moved to new ground every two weeks, leaving calved-out pairs behind. This keeps calving lots clean, and moving new pairs to a clean pasture can minimize contamination. Thus, the younger calves are never exposed to feces from older calves that may be scouring.

“Vaccines can be helpful, but don’t depend on them as a crutch. You can vaccinate a cow multiple times, but if she’s lying in manure and the calf gets a mouthful of E. coli during birth (before he gets colostrum), he won’t be protected. Even if it nurses quickly, dirty teats can harbor E. coli or Salmonella; that calf will probably get sick.” It’s always a race between antibodies and pathogens, to get to the calf’s gastrointestinal tract first, she says.

A scours problem can vary from year to year, depending on weather conditions and how wet/muddy calving areas might be – and how dirty cows are. Cow vaccination might precede a better following year, leading a producer to think the vaccine worked. In reality, the lower sickness rate might be due to drier, cleaner conditions.

“A scours problem can also vary within the same herd, between heifers and cows. If you maintain them in separate pastures, this can make a difference,” Laflin says.

On average, heifers have less quantity and quality of colostrum. Often the volume is less than from a mature cow, and a heifer hasn’t been exposed to as many different types of pathogens in her short life. To protect heifers’ calves, address any management issues and make sure heifers are appropriately vaccinated.

Heather Smith Thomas is a rancher and freelance writer in Salmon, ID.