Video 7 IBR the facts
What is IBR?
Infectious Bovine Rhinotracheitis is an infectious viral disease of cattle that is contagious. It belongs to a family of viruses called herpes virus. These viruses are different because they can develop latency. This means after initially becoming infected the animal may get sick or not. Then the virus subsequently goes into hiding (in the nervous system) and can reactivate or reappear in times of stress. This means these animals often don’t get sick again but will shed the virus to infect other animals.
People will be familiar with the cold sore virus which acts in a very similar fashion in humans.
Symptoms?
The virus affects the upper respiratory system of cattle. It can cause irritation and reddening of the airways and eyes. It can cause coughing and breathing difficulty. A lot of animals which become sick with the virus and will run a temperature over 40 degrees Celsius.
It can also shed out to the bloodstream causing fertility issues and abortion.
How is it spread?
It can be spread in aerosol secretions from sick infected animals. This is usually by close contact or in the same airspace. Another reason why ventilation, giving animals space and fresh air is so important indoors.
Also, adult animals shedding the disease can pose a risk to younger stock with little or no immunity.
Latently infected carries can also shed the virus when reactivated through some stressors. They will not shed as much virus as infected animals but can be a significant source of infection. The real risk here is when we buy in these carrier animals (look healthy) they can then start shedding in the herd when becoming stressed.
I have seen examples of this where cows are bought in and at calving time start shedding.
They then can infect other cows at calving who are stressed causing significant clinical disease.
Watch the VIDEO above as I talk about the mechanism by which IBR sheds and spreads.
IBR can cause significant issues with sick animals and disease. Not just the respiratory disease, but infertility and immunosuppression.
How can we test for it?
Thankfully we have very effective tests for the IBR virus. We can use blood samples to check for antibodies or use milk samples in dairy cows. I find bulk milk screening tests very useful for monitoring IBR levels in the dairy herd.
We must remember though these antibody levels can remain high even after vaccination programs. With good vaccination programs, IBR levels should have dropped back to very low levels on bulk milk tests after three years.
We can also test animals for IBR using nasal swabs in suspect clinical cases. We can also check the windpipe of animals we have carried out post mortems on.
Control strategies
If your herd is IBR free then we must have very strict biosecurity to prevent the disease being bought in. This can be very difficult so most farms will incorporate vaccination as part of their control strategies.
IBR vaccination control programs work very well once the vaccine is used correctly and timed to protect animals at the greatest period of risk.
Thought for the day
My own experience over the last 2 weeks is the significant disruption has led to me personally losing focus. It can happen but it is important to always try and focus on key jobs at key times.
So my tip today is to remain focused on what’s important in work but most importantly in life.
If people feel I can help them in any way my email is info@tommythevet.ie
Big thanks to Nettex for their support in helping me make #50in50 happen
Happy safe farming