How to boost cows' immunity to disease
A long-term plan is essential for dealing with respiratory conditions in dairy herds
Over the last two months, I've been dealing with a number of herd problems with respiratory disease in cows at pasture. There is a lot of confusion about the causes of this problem and it can be very frustrating for farmers as it can have a significant impact on production.
Unfortunately, there is rarely a simple solution because often, when this type of herd problem occurs, there can be several things involved or contributing.
I'm not talking here about individual coughing or sick cows, but herd problems usually with large numbers of cows affected.
These cases, in my experience, are usually caused by infectious agents such as viruses or parasites.
What can complicate the situation is sometimes there will be a combination of things affecting the herd at pasture. We also need to find out if there is any reason for the herd immunity to be dropping. Anything that affects immunity will leave cows more prone to shedding and becoming infected, particularly with viruses.
The main causes of coughing I have diagnosed in the last two months have been viruses and lungworms. The viruses I have found have been RSV, PI3, IBR and coronavirus. For some reason, the first disease everyone talks about when talking pneumonia in cattle at the moment is IBR.
My experience is, yes, it does cause the clinical signs of milk drop and coughing, but it is not the only agent I have isolated. Of course, it is a hugely significant worldwide disease and many countries are now trying to eradicate it.
However, we need to move away from blaming it exclusively for the coughing cow. Instead, we should make an attempt to definitively find the cause, or causes, of the coughing.