By Jeff Sarchet, DVM, MPH, DACVPM, DABVP, Zoetis Beef Technical Services
As cow/calf producers and veterinarians evaluate options for pre-breeding vaccinations on heifers and cows it is critical to think about the long-term effects of the disease pathogens that you are protecting against. The immediate thought is protecting against vibriosis and leptospirosis; sometimes that occurs at the sacrifice of not effectively protecting against the reproductive forms of bovine viral diarrhea virus (BVDV) types 1 and 2 and infectious bovine rhinotracheitis (IBR), which may have larger effects on overall health of the herd and greater financial implications for the producer.
In developing a vaccination plan for the cowherd, it’s important to understand the potential impact of each disease challenge.
- BVDV has the greatest long-term impact if allowed to enter the herd. If cows or heifers are exposed to BVDV during pregnancy, those pregnancies are at risk of early embryonic death, abortion, birth defects, or stillbirth. Or if exposed in the first 140 days of pregnancy, the unborn calf can become infected for life with BVDV, which is called BVD persistent infection (BVD-PI). A calf born as BVD-PI will shed the virus and be a carrier as long as it is alive. BVD-PI calves nursing their dams allows for BVD exposure to other nursing calves as well as other dams and their unborn calves in next year’s calf crop.
- IBR can cause an abortion storm in naïve cows that are exposed. Overall, IBR causes fetal losses and is costly to producers.
- Leptospirosis has five main strains: Leptospira canicola, L. grippotyphosa, L. hardjo, L. icterohaemorrhagiae, and L. pomona. The five most common strains of Leptospira can cause abortions or pregnancy loss or less commonly make animals sick with kidney disease. Another less obvious, but important strain is Leptospira borgpetersenii serovar Hardjo-type hardjo-bovis (HB). Most commonly, Lepto hardjo-bovis causes early embryonic death manifested as conception issues. Leptospirosis protection from the five most common strains only lasts six months, but some Lepto hardjo-bovis vaccines have a duration of immunity of 12 months which needs to be considered when developing a vaccination program
- Vibriosis (Campylobacter fetus) is a sexually-transmitted disease that can cause infertility, irregular estrus cycles, delayed conception, and occasionally abortion.
When I designed vaccination programs for my clients, I asked a series of questions to help me give them a program that would be most effective in protecting the cowherd but also fit their management style. The first question I asked was if they could work the cows and calves prior to bull turnout. If this is the case, you have several options for the cows and calves because the cows are not pregnant at this time so giving the calves a modified-live virus (MLV) vaccination is safe even though the calves are nursing, and it is also safe to give the cows a MLV vaccination, like the Bovi-Shield GOLD FP® vaccines, because they are not pregnant. It is important to look for FP in the name of the vaccine because that means the product is indicated to protect against the reproductive consequences of BVDV and IBR.
If a producer doesn’t handle the cowherd at pre-breeding, vaccination history is unknown, or the client is uncomfortable with MLV vaccination, I would recommend using a product like CattleMaster Gold FP®, a killed BVD reproductive vaccine that provides protection against BVD-PI and IBR abortions. Not every killed virus vaccine has reproductive protection, so make sure to read the label indications.
If Leptospira borgpetersenii serovar Hardjo-type hardjo-bovis (HB) is a potential challenge, then it is important to add a vaccine that protects against that type of Leptospira; otherwise, protection against the basic five Leptospira strains is adequate.
The final disease to consider is vibriosis. If vibriosis is a potential problem then I recommend using a product that incorporates vibrio protection with BVD-PI and IBR abortion indications, or a stand-alone product for vibrio protection at pre-breeding. It is key that vibrio protection is given at pre-breeding to protect against early embryonic loss and reduced conception rates because like the common 5-way Lepto vaccines, vibrio vaccines typically only have a duration of immunity of 5-6 months.
Again, it is important to think beyond protecting just against vibrio and leptospirosis. BVD persistent infection and losses due to abortion storms caused by IBR exposure have greater financial impact on the cowherd and can have lasting consequences on herd health and sustainability.
Last of all don’t forget to vaccinate your bulls. These diseases can be transmitted by the bulls either through direct contact or venerably during breeding. Bulls are also vulnerable to contracting these diseases from infected cows or calves, especially BVD-PI calves. BVDV has a predilection to reproduce in testicular tissue which can then be transmitted through the semen during breeding. Some vaccines have the label indication for protection from BVD testicular infection.
Vaccination is one part of ensuring a healthy herd, but biosecurity and disease surveillance/testing are also important. Work with your veterinarian to help develop the most effective and comprehensive herd health program that will work for your management to help protect your whole herd and help set your future calf crops up for success.
Do not use in pregnant cattle (abortions can result) unless they were vaccinated, according to label directions, with any Bovi-Shield GOLD FP or PregGuard GOLD FP vaccine prebreeding initially and within 12 months thereafter. Do not use in calves nursing pregnant cows unless their dams were vaccinated within the past 12 months as described above. To help ensure safety in pregnant cattle, heifers must receive at least 2 doses of any Bovi-Shield GOLD FP or PregGuard GOLD FP vaccine with the second dose administered approximately 30 days prebreeding.
About Zoetis
As the world’s leading animal health company, Zoetis is driven by a singular purpose: to nurture our world and humankind by advancing care for animals. After innovating ways to predict, prevent, detect, and treat animal illness for more than 70 years, Zoetis continues to stand by those raising and caring for animals worldwide — from veterinarians and pet owners to livestock farmers and ranchers. The company’s leading portfolio and pipeline of medicines, vaccines, diagnostics and technologies make a difference in over 100 countries. A Fortune 500 company, Zoetis generated revenue of $8.1 billion in 2022 with approximately 13,800 employees. For more, visit zoetis.com.