Teatime for Tiddles

I was interested to see that the Chancellor of the Exchequer Alistair Darling has moved his cat into Number 10 Downing Street to deal with 'a mouse problem' and was wondering what the tax implications were.

Let's say that an employee lives in job-related housing and the house has an infestation of mice. If the employer pays for the food etc. of the occupant's cat until the problem is solved would this be allowable for tax purposes in the employer's hands and would this be a benefit in kind on the employee as part of the running costs of the property?

I then started to wonder whether there were other similar cases where tax reliefs or liabilities might arise. The query 'The Dog and Duck' (Taxation 5/12 April 2007 page 415) dealt with guard dogs but I am aware of...