Are race winnings taxable/ require a tax return?

Hi, I have a client who trains and races Greyhound dogs and their income is just the prize winnings. Is this taxable? and also, are they required to complete a tax return like a self employed person would?

Hi,
Generally, we do not consider greyhound racing to be a taxable activity. Prize money from Greyhound racing is generally non taxable and there is no tax relief available for buying the dogs or any of their training costs.  
Section 30 ITTOIA 2005 specifically states that animals kept wholly or mainly for racing or other competitive purposes should not be treated as trading stock. We have a similar position in respect of horse racing. Yoiu can seeguidance here:
BIM55701 - Farming: stud farms: overview
Greyhound racing prize money, in itself, would not constitute a criteria for completing a tax return.
Thank you.