Taxation re training/breeding horses

A farmer who buys a horse (imports it from say New Zealand), trains the horse and then sells it - are the profits from this activity taxable? I am aware that profits from racing activities are regards as a hobby for an individual and not taxable - would the above constitute a racing activity and hence not be taxable?

Also, if a farmer were to breed horses, then train them and sell after a couple of years, are the proceeds split between breeding (ie farming and taxable) and racing (hobby and not taxable). How would you split this?

Has anyone out there any good references on how to deal with tax in the bloodstock industry?

sounds like a business to me, afaik only the stallion fees are tax exempt,