If not, be sure to take some shorter hikes first to build the dog's endurance. Dogs require lots of water, and if you are planning a hike where water is limited, you will have to carry the weight of this extra water in YOUR pack. Figure one bottle per day minimum in spring and fall and more than this when the temperature is over 75.
Dog packs are great.
Be sure that you give Fido a chance to take a couple of walks around the neighborhood with his new pack before hitting the trail - even some of the most outgoing dogs need to learn that they can still walk with this thing on their backs. Do not pack heavy items in the dog pack, and make sure it is evenly weighted, and fits the dog properly. Check Fido over carefully at breaks and make sure the pack is not causing irritation. If irritation exists, and adjusting the pack does not seem to help, then you need to be prepared to add his pack to your own load. Set your tent up in the living room and let the dog explore it.