Davie,sorry cant give specifics as it is some time since we did this as our children are now grown up.However I would suggest you select the area you want go through the cls listed for those that either say animals on site or where the address is a farm and ring and ask the question.I would guess if a farm has animals such as goats pigs chickens cows etc and the question is asked nicely and the farmer reassured that the children will be accompanied they will agree.Nowadays of course everyone panics about health and safety so you will nedd to make him confident that they are controlled,it will take a bit of work but worth it believe me.Try a post on here under uk parks and see if anyone else can help with specifics I would be interested to hear how you get on.