yes its great for dogs. if you watch a dog in outdoors they will often chew on grass occasionally, especially if they are getting sick. they know to do this because they somehow realize they need the minerals in the grass to fight off infection. you can give as much wheatgrass to your dog as you like, its impossible to overdose on it.

you could simply go out and juice wild growing grasses for your dog too, it would be cheaper. free in fact.