Proper timing is crucial for calf vaccinations
Published on March 21, 2020
Newborn calves gain temporary, passive immunity from disease when they ingest colostrum from the dam. This first milk contains maternal antibodies. After a few weeks or months, this temporary protection begins to wane, however, and calves must build their own immunities.
Vaccinating calves at the proper time can help them create immunity and protect them until weaning age. Vaccinating too soon may not stimulate much immune response, however.
If the calf still has maternal antibodies in its system, these tend to interfere with building its own immunities to certain disease conditions because the body sees no need to respond.
Dr. Tom Hairgrove, Texas A&M University Extension veterinarian, stresses the importance of talking with local veterinarians to build a health plan and vaccination program appropriate for the specific area.
This may include pre-calving vaccination for the cows, so they will have adequate antibodies in colostrum.
“The calves themselves should be vaccinated by the time temporary immunity from colostrum wears off,” he says. “Most calves are vaccinated at about 90 days of age, usually around branding time, which generally stimulates immune response.”
A few ranchers vaccinate calves at birth to give protection against certain scours pathogens, such as an oral E. coli vaccine, but this is a case-by-case program.
The age for routine vaccinations will vary, depending on the individual ranch’s facilities and goals. There’s been debate among veterinarians during the past decade regarding timing.
“All too often, producers want a canned program and for us to lay out exactly what to give and when to give it. But I can’t give them this,” says Hairgrove. “I can tell them which diseases they should try to protect their herd from, but how they do it will vary in terms of their own situation and expectations.”
Hairgrove notes it may make a difference whether the operation is a seedstock business or what the neighbor is doing.
“We can’t protect our animals with a vaccine if the guy next door is trading calves all the time and bringing in new cattle that may bring diseases with them,” he says. “No vaccine is 100 percent protective. Producers also need to take other precautions to prevent exposure to these diseases or they may still have some issues.”
At about 90 days of age, Hairgrove recommends all calves receive a blackleg vaccine, which would include other clostridials in classic seven- or eight-way vaccines.
Hairgrove explains, “In Gulf Coast states, and in much of the Rocky Mountain region, many ranchers need to include redwater for protection against C. hemolyticum.”
“This can vary from ranch to ranch, depending on the risks, which include the presence of liver flukes, which damage the liver and open the way for infection with C. hemolyticum,” he says.
“Use a clostridial vaccine that’s appropriate for the locality. In some areas, calves become infected with tetanus after routine castration, and if ranchers use banding for castration, vaccination for tetanus is essential,” he stresses.
Blackleg is always present in the environment and clostridial vaccines should always include it.
“I recommend people carefully follow label directions when using clostridial vaccines,” he suggests. “I tell producers to vaccinate their calves and then booster according to the label. The booster is critical or we may end up with dead calves.”
Hairgrove notes producers should carefully follow label guidelines and ensure they are giving the proper dosage. Clostridial vaccines may come in a two-milliliter dose or a five-milliliter dose.
“The two-milliliter dose is fine, but just make sure to accurately give the full two milliliters. If someone is using a 50-milliliter syringe and adjusting it to give two milliliter doses, it won’t be as accurate as a smaller size syringe will be,” he explains.
“If even a little bit of air gets in that syringe, we lose a half milliliter in that dose, and have lost 25 percent of that product,” he says.
“If it’s a five-milliliter dose and we lose half a milliliter, we’ve lost 10 percent of that product, and that might make a difference on whether or not it will work,” he says.
The clostridial vaccines are notorious for injection site reactions such as temporary lumps and swellings, and producers may see less issues with the smaller dose.
Some producers also try to protect their calves from so-called summer pneumonia and other respiratory issues in nursing-age calves.
“Usually we don’t see this problem unless the calves are stressed,” he explains. “I’ve had producers tell me they had issues with this in the past, and then started adding the mannheimia pasteurella vaccines at branding and felt that it helps a lot. Vaccination seems to be most effective at this age rather than waiting until weaning.”
The vaccinations at weaning then act as a booster.
“I recommend giving the viral vaccines at branding time, along with a mannheimia vaccine,” he says.
He continues, “A lot of people don’t think it’s necessary to vaccinate pre-weaning because their calves are just going to the sale barn post-weaning. But, for the good of the industry, the calves need to be vaccinated. Otherwise, those calves are at high risk of getting sick when they go through the sale barn.”
“For calves that will be kept as replacement heifers, I stress the importance of a good lepto, bovine viral diarrhea (BVD) and infectious bovine rhinotracheitis (IBR) vaccines,” he says.
“If we are giving calves killed or modified live (MLV) IBR-BVD, do not give MLV to calves nursing improperly vaccinated dams and always booster these products as labeled. Killed products always require a booster,” says Hairgrove.
Hairgrove notes improperly vaccinating dams or calves with MLV products can be catastrophic.
“MLV and killed vaccines are both excellent products, and both have pros and cons,” he says. “Vaccine programs must be tailored to the operation and management.”
“For replacements, always vaccinate with what’s appropriate pre-weaning. For post-weaning, there are several different combinations of vaccines to be used,” he says. “The modified live and the killed vaccines are all very good, if given properly.”
Hairgroves stresses heifers should be kept up-to-date on vaccinations, especially as they approach breeding age.
“The heifers’ vaccinations are crucial because they provide the foundation for future immunity for the rest of their lives,” he says. “It’s like when our kids start to go to school. We need to get the initial immunity.”
He also recommends vaccinating heifers for brucellosis. States near Yellowstone Park including Idaho, Montana and Wyoming have mandatory calf vaccination programs because there is still a problem with brucellosis in bison and elk herds in and around the park. Every heifer must be vaccinated between four and 10 months of age.
“Consult with a local veterinarian about vaccinating heifers for important diseases and don’t forget brucellosis,” he says. “If cows ever go to another state, they may need the calf brucellosis vaccination in order to enter that state.”