Personally I would not put one on a dog for any type of training until the dog is 11-12 mos. old.

 

I'm with fishinlk on this one. Take the next 6 months and bond with your dog. Concentrate on the commands that he knows, then praise him. This gives him confidence. Slowly work in some of the things that he's not so good at, but make it fun.
He's still got a lot of puppy in him. That's not to say that he won't learn at this age, he just needs some time to build confidence in himself, and trust in you. A shock collar at this stage (IMO) would do more harm than good. Wait until he's at least a year old.
Take the next 6 months, and talk to experienced trainers who are familiar with the proper use of e-collars. Read everything that you can get your hands on concerning the subject.
It takes a long time to properly train a dog. It takes a surprisingly short time to ruin one.

 

I don't think there is any given age to use a E-Collar. I don't like to use them untill the dog is mature enough to know what is going on. For a puppy that is under a year old should just be allowed it be a puppy. A puppy can learn a lot at this age without a lot of pressure. Be sure the puppy is well socilizes and huminized, a puppy cannot lear in fear. Go slow with pup, build the pups confidence in you and what he is doing right with a l;ot of praise

E-Collar is an important tool in training, but you must know how to use them properly. More dogs are ruined with people that do not know how to properly collar condition the dog or the dog will get collar wise. Impropper use of the collar will surely ruin a dog.
An E-Collar should be used for correction rather than for training.


A good video is George Hickox (Training pointing dogs.)