Ah yes, that would do it.   It is well known that bumping into a pig causes measles, tripping over a chicken gives you rickets and colliding with cow makes you mental.  There is an operation you can have to reverse the process, but there are three main drawbacks.  Firstly, it is very costly, and there are only a handful of surgeons in the world who can perform it.   Secondly, it is extremely painful, and can involve the loss of one or more limbs.  And thirdly, it doesn't work.

In spite of this there are still many people on the waiting list - which, if nothing else, at least proves that they are genuinely mental.  Still, there are very few options available when it comes to curing cow-induced mentalism.  Have you tried repeatedly bashing yourself about the head with a brick?