I was driving to see a cow at Tommy’s recently. The call was to a cow down after calving and as he had already had a few cows that slipped in the yard and ended up in similar circumstances I was expecting to see yet another one when I arrived.
I was trying to work out in my head just why he was having so many of these cases and also what suggestions I might come up with to improve his situation.
The cow was out in the field, lying on her side. I drove out to the paddock and pulled up beside her.
She looked to be in a terrible state. Tommy had told me in the yard that she had mastitis. So all the thoughts that had been going through my head on the journey were all in vain!
My patient was groaning as I took her temperature, which was very low. I looked at her eyes and saw they were bloodshot. She was not a good looking subject.
Tommy told me that she had mastitis in the back left quarter so I pulled the other three first. The back right quarter also had a watery like mastitis.
The one Tommy told me about had a brown coloured liquid coming from it. I kept drawing it until I could get no more expecting at some point to hear the sound of gas. On this occasion there was no gas but there was still no mistaking the presence of a gangrenous mastitis.
Every now and then I come across a case of this and there is still no easy way to break the news to the farmer that in all probability his cow is going to die. Over the years I have seen a few survive but not too many as they are usually too far gone to save them when we get the call.
My friend, Peter Edmonson, writes in his book on mastitis that such cows may have a chronic staph aureus infection for months or even years causing nothing more than a high somatic cell count when all of sudden it changes to a full blown gangrenous mastitis.
We are told that the animal’s immune system is compromised and that massive amounts of toxin are produced, overwhelming the poor cow.
It is not caused by a specific acute strain or a change in strain of the staph aureus. In very rare cases these kind of changes can be caused by an e.coli infection.
Presumably around the time of calving the animal comes under pressure and is not able to fight off infection as she normally would. Her immune status is lowered. Some cows have been known to survive and those that do may lose the affected quarter which will simply fall off with the resultant wound healing in its own time.
As the disease progresses the quarter becomes cold and often changes colour to a blue, purple or black shade. On drawing the teat the skin may peel off as you do so.
In all eventualities, the best outcome for the cow is to cull her as the outcome is usually pretty hopeless.
One word of warning is to have your vet look at the cow first. Sometimes a cow can have a discolouration of the udder due to an injury and what you are seeing is just a bruising.
Your vet will, upon examining the cow, be able to ascertain from the cow’s parameters what exactly is going on and advise you accordingly. It would be an awful mistake to make the decision yourself and send a perfectly healthy cow to the knackery.