I have been doing agility with Molly 7yr old Beagle for about 5 years now. Beagles are very food motivated which sometimes works to my advantage. To compete in agility you cannot use treats at all in the ring. What I suggest is slowly phasing out the treats while doing obstacles. To do this you have to start small, if he completes two obstacles have a party and give a treat. Then one obstacle have a party get a treat, next time it is 5 obstacles, keep him guessing, so he will never know if after this obstacle he will get a treat. Eventually you should be able to work up to an entire course with no treat. If he stops working for you don't give in and give him a treat (he has you trained to do this) game over for about 5 minutes and try again. It should not take him long to figure out that you are in control of the treats and the game and what you say goes(you are Alpha dog). What I also do with Molly is at the end of the run she gets a "jackpot" which is several small cookies that I feed to her right after our run praising her as she is eating them. I be sure to show her the "jackpot" before we head out in the ring and when we are finished she is excited and heads right for the treat. I hope this helps. The key here is patience and consistancy.