Vaccination Effects on Reproduction By Hannah Wine
As a cow-calf producer, you’ve invested in the best genetics you can get, studied pedigrees, analyzed EPDs, built marketing programs, and much, much more. Those top-of-the-line pedigrees and trait-leading EPDs are not of much value without calves on the ground to turn a profit. Reproductive performance of your cowherd is critical.
The effects of your vaccination program can often be hard to see, which makes it extra imperative to ensure that vaccinations aren’t the reproductive management mistake undoing all of your hard work.
There are numerous factors that affect reproductive efficiency, such as heifer development, nutrition, cow body condition, bull fertility and more. George Perry, PhD, from the Department of Animal Science at South Dakota State University, explains one very important detail about reproductive management, “The things you do well do not compensate for the mistakes you make. Instead, the mistakes you make cancel out all of the things you do well.”
n Infectious Diseases Affecting Reproduction here are a host of different diseases such as BVD, IBR, Trich, Lepto, Vibrio and more that can affect reproduction. Bovine Viral Diarrhea (BVD) and Infectious Bovine Rhinotracheitis (IBR or “Red-nose”) are two viruses that impact reproductive performance by decreasing conception rates and embryonic loss. BVD is widespread throughout cattle herds in the United States and the world. BVD is spread through body fluids, including saliva, respiratory secretions and manure. The virus doesn’t linger in the environment, but it can survive long enough to be transferred with infected equipment, needles and palpation sleeves. Signs of BVD depend on the stage of gestation when the cow is infected. “Infection during mid-gestation may result in the formation of persistently infected calves, which occurs as a result of infection during a period of fetal development, roughly between 40 – 120 days of gestation. Persistently infected
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calves have incorporated the virus into their own body and will shed high levels of the virus throughout their lifetime. Later infections may result in congenital defects, late-term abortions or the birth of congenitally infected calves, which are weaker and more prone to illness than normal calves,” explaines Dr. Perry. IBR or “Red-nose” is a herpes virus (in the same family as viruses causing cold sores in people). It is typically dormant in nerve clusters in the throat area or lower spine and reactivated during times of stress. Any animal exposed to IBR in the past could potentially shed the virus to susceptible animals. IBR is transmitted in nasal secretions from infected animals. IBR affects both the respiratory tract and the reproductive tract. Reproductively, IBR typically results in infertility or early embryonic death and it is also one of the most frequently diagnosed viral causes of late-term abortions (fifth to ninth month of gestation).