just plain natural fun is what i say. as cityfolk we dont get that many opportunities to go and see a cow unless its appearing on our plates with some frites, or a horse unless its being chomped on by our pets or even a goat unless we are slathering its milk-turned-chevre onto our bruschette. so here is your chance. take the kiddies and get close enough to smell all you like (for better or for worse) to even feed some grass to a pony or a horse (with supervision - you probably arent allowed to actually).
and learn to: i didnt realize that pigs can grow that big. i was quite happy she was fenced in and i was protected - easily a good candidate for a new batman movie villain. i think that any adult will be just as tickled as any kid they bring along to have a taste of rural wildlife in this little zoo or farm (dont know that either moniker fits but it is what it is.)