A horse actually has two friendly tubes. It is difficult to figure out what the tubes on a horse are since they don't really have a paw to shake, nor do they wrap around anyone to communicate friendship. However, if you watch closely, you'll find that the horse's friendly tubes are his ears. You will notice that a horse, to communicate friendship, will rotate and point his ears towards you. If he didn't like you, he wouldn't point his ears. Therefore, the horse's tubes are his ears.
