All cattle, whether beef or dairy, need vaccines against four respiratory viruses and a group of bacterial diseases caused by Clostridium. These are considered core vaccines by the American Association of Bovine Practitioners, meaning every cow should receive them regardless of where it lives or how it’s raised. Beyond that core set, breeding herds need reproductive vaccines, calves follow their own schedule, and certain regional diseases call for additional protection.
The Five Core Vaccines
Core cattle vaccines target the pathogens most likely to cause serious illness in any herd, anywhere. Four of them protect against the viruses behind bovine respiratory disease, the single biggest killer of cattle. The fifth protects against a family of soil-borne bacteria that cause rapid, often fatal infections.
The four respiratory viruses are:
- IBR (infectious bovine rhinotracheitis), a herpes virus that attacks the upper airways and can also cause reproductive failure
- BVD (bovine viral diarrhea), types 1 and 2, which suppresses the immune system and can cause persistent infection in calves exposed before birth
- PI3 (parainfluenza 3), a virus that damages the lining of the respiratory tract and opens the door for bacterial pneumonia
- BRSV (bovine respiratory syncytial virus), which causes severe lung inflammation, especially in young calves
These four are commonly bundled into a single combination vaccine, available in both modified-live and killed versions. Modified-live vaccines produce a stronger immune response but carry restrictions for pregnant animals, so the choice depends on your herd’s situation.
The fifth core vaccine is a clostridial combination, typically sold as a “7-way” or “8-way” product. It covers blackleg (caused by C. chauvoei), malignant edema or gas gangrene (C. septicum), and several types of C. perfringens that cause enterotoxemia, along with C. novyi and C. sordellii. These bacteria live in soil and can enter the body through small wounds or the digestive tract. Blackleg alone can kill a healthy calf within 24 hours, which is why clostridial vaccines are given early and boosted consistently.
Calf Vaccination Timeline
Calves get their first round of vaccines at 2 to 4 months of age, typically at branding. This initial dose includes the 7- or 8-way clostridial vaccine plus the four-way respiratory virus combination. Think of this first dose as a primer. It introduces the calf’s immune system to these pathogens but doesn’t provide full protection on its own.
A booster follows 2 to 4 weeks before weaning or at weaning itself. If you’re boosting at weaning, let calves settle overnight before processing them. Stress raises cortisol levels, which blunts the immune response, so giving the animals time to calm down produces better immunity. The clostridial booster needs to come 3 to 4 weeks after the initial dose to be effective.
The strongest protocol is a priming dose at branding followed by two boosters spread across a 45- to 60-day weaning period, ideally while calves are still on the home ranch. If that’s not practical, getting at least one booster into calves before they leave the cow gives them meaningful protection before the stress of shipping and commingling.
Vaccines for Breeding Herds
Breeding cattle need additional vaccines to prevent reproductive losses like embryonic death, abortion, and stillbirth. The two most common are for leptospirosis and vibriosis (campylobacteriosis).
Leptospirosis vaccines cover multiple strains of bacteria that spread through contaminated water and urine from wildlife. Some strains provide only short-lived immunity, so cows often need a dose before breeding and a second dose at pregnancy check to stay protected through the full gestation. Bulls also receive leptospirosis vaccine before the breeding season.
Vibriosis vaccine protects against a bacterium that colonizes the reproductive tract and causes early embryonic death and infertility. It’s given pre-breeding to both cows and bulls. Both leptospirosis and vibriosis vaccines are killed products, which means animals getting them for the first time need two doses spaced 2 to 6 weeks apart. Replacement heifers that have never been vaccinated can receive their first dose 60 days before breeding and the second at 30 days, or start at 30 days and repeat at the start of the breeding season.
Brucellosis: A Special Case
Brucellosis vaccination stands apart from the rest because it’s federally regulated. The RB51 vaccine is licensed only for non-pregnant female cattle between 4 and 12 months of age, and it must be administered by an accredited veterinarian or a state or federal animal health official. You cannot legally give this vaccine yourself.
The vaccine is roughly 70 to 80 percent effective at preventing brucellosis, a bacterial disease that causes abortion in cattle and can spread to humans through unpasteurized milk or direct contact with infected animals. Many states require official brucellosis vaccination for heifers, especially if they’ll be sold across state lines, so check your state’s requirements.
Dairy-Specific Vaccines
Dairy cows benefit from everything above plus vaccines targeting mastitis, the costly udder infection that plagues dairy operations. The most widely used is a J-5 E. coli bacterin, given during the dry period to reduce the severity of coliform mastitis after calving.
The typical schedule is one dose at dry-off (about 8 weeks before calving) and a second dose at mid-dry period (4 weeks before the due date). In challenge studies, vaccinated cows shed significantly less bacteria in their milk and maintained milk production the day after infection, losing essentially nothing, while unvaccinated cows dropped nearly 8 kilograms of milk. The inflammatory response was also dramatically lower: vaccinated cows had an average somatic cell count around 490,000 per milliliter in the affected quarter compared to over 5.4 million per milliliter in unvaccinated controls.
Regional and Risk-Based Vaccines
Some vaccines only make sense in certain environments or management situations. Your veterinarian can help identify which of these apply to your operation.
- Anthrax is a concern only in limited geographic areas with alkaline soils that allow bacterial spores to survive for decades. Cattle in endemic zones should be vaccinated 4 weeks before turnout on those pastures. In heavily contaminated environments, a second dose 2 to 3 weeks later adds protection.
- Pinkeye (Moraxella bovis) vaccines are used in herds with a history of outbreaks, particularly where tall grass, flies, and UV exposure increase risk. Efficacy varies because the bacteria have multiple strains, and the strain circulating in your herd may not match what’s in the vaccine.
- Anaplasmosis is a tick-borne blood disease found in the southern and western United States. No commercial vaccine is currently available in the U.S., so prevention relies on tick control and, in some cases, feed-grade antibiotics during high-risk seasons.
- Tetanus and red water disease (C. hemolyticum) are not considered core by the AABP but are included in some clostridial combination products. They’re worth considering if your area has a history of either disease.
Storing Vaccines Properly
Vaccines lose potency when stored at the wrong temperature, and this is a common on-farm problem. The recommended storage range for virtually all cattle vaccines is between 2°C and 8°C (about 36°F to 46°F). That means a dedicated refrigerator with a thermometer you actually check. A standard household fridge works, but the door shelves and the back wall tend to run too warm and too cold, respectively.
Freezing is just as damaging as heat. Killed vaccines and bacterins that freeze can lose their effectiveness entirely, and there’s no way to tell by looking at them. Modified-live vaccines should be mixed and used within about an hour, kept cool, and protected from direct sunlight. Ultraviolet light breaks down the live organisms quickly. If you’re working cattle outdoors, keep your syringes in a cooler with ice packs and a barrier (like a towel) between the vaccines and the ice to prevent freezing.