A crate is not a substitute for human companionship. Use of a crate should be limited to no more than eight hours, less for a younger animal. If your work schedule is longer than that, consider getting a dog walker to exercise Puppy or Doggy for you midday. There are also Dog Day Care centers cropping up! Make sure he has fresh water, a sturdy bed and safe toys (rotate toys daily so he always has different ones and a different combination).

This does seem like a very long time to be leaving such a young dog, you should try experimenting to see if he can be trusted to be outside the crate. If you think your dog is able to behave uncrated, begin testing by leaving his loose for five minutes while you walk outside. If that works, increase to ten, fifteen and so on. Should he begin to misbehave, continue using the crate.