Reproductive and Herd Health

There are a lot of components to pre-breeding vaccinations. A general outline of viruses important to respiratory and  reproductive health are outlined below. Ensure that the following are included in your pre-breeding vaccines. 

1. Bovine Viral Diarrhea Virus, also known as BVD or BVDV can affect the respiratory, reproductive, and gastrointestinal systems of cattle. In cows, infection with this virus during the first 150 days of pregnancy can result in a persistently infected (PI) calf. The immune system of a BVD-PI calf recognizes the BVD virus as self, which results in the calf replicating and shedding this virus throughout its lifetime. The PI calf sheds virus particles in respiratory secretions, causing respiratory disease in neighboring calves. In addition, PI calves that are exposed to cytopathic strains of BVD can develop mucosal disease, which affects the digestive tract and commonly results in death of the calf. 

2. Infectious Bovine Rhinotracheitis, or IBR, a highly contagious respiratory infection, can also cause infertility or abortion in cows. When using a modified-live vaccine, the IBR component can cause inflammation around the ovary and can either lead to reduced pregnancy rates in the first cycle following vaccination, or abortion in pregnant cattle.

3. Parainfluenza 3, also known as PI3, is a virus that primarily causes respiratory disease and is especially problematic when combined with BVD or IBR, often leading to secondary bacterial infections and contributing to bovine respiratory disease complex (BRD). 

4. Respiratory Syncytial Virus or BRSV is another viral component that primarily causes respiratory disease in calves and contributes to bovine respiratory disease complex (BRD). 

Vibriosis is caused by the bacteria Campylobacter fetus, which is spread venerally by asymptomatic bulls. Infection causes reduced pregnancy rates by preventing embryo implantation or causing early pregnancy loss. 

Leptospirosis is a bacteria with many different serotypes, with Leptospira borgpetersenii serovar Hardjo type hardjo-bovis being one of the most significant causes of Leptospirosis infections in the US. Most vaccines contain 5 strains of Leptospirosis. Leptospirosis is spread through the urine of infected animals, which infects cows through the mucosa in the mouth and nose leading to infertility and abortion in cattle. It is generally recommended to booster vaccinations including leptospirosis when cows are in the second period of pregnancy.