I have to agree with the above posts - physically, yes, he may be able to breed. But I think the question is WHY would you want to breed a dog that young? I can't even imagine a scenario that would make me want to breed a dog that is not even close to reaching his fully developed state (Temperament, Body etc)
At 24 months OFA can be done, I suggest Hips, Elbows, Heart and Thyroid at a minimum - that's right, a minumum. There is no excuse for not health testing the WHOLE dog, not just one section. The tests are affordable and can be done by an experienced vet.
Both parents need them, even better if you have generations of dogs behind them that are tested too!
Then get out there and get a third party evaluation(s) of your dog by someone that does NOT have a vested interest in the dog.
The only reason to breed is to improve on the last generation - when I breed, I want the next generation to come out better than the one I started with. ALL AROUND, balanced, stable working dogs who are versatile enough to work in multiple venues (Herding, sport work, service etc). If you do not have a goal set forth, that is where I would start. Ask yourself "What am I trying to accomplish with this breeding?".
Be honest about your dogs strengths and weaknesses. Will this breeding improve upon them?
Just my opinion, but hope it helps!