could you please tell me at what age is best for a Cavalier king charles dog  bbefore he can mate with a bitch???????????

It isn't so much a question of age but when he has passed his health tests.  He should ideally not be bred from until he has been heart tested over two years of age, or if younger that both his parents are still heart clear at over five years of age. 

There is also another hereditary condition that needs an MRI scan to detect.  I would expect that they should also be eye tested and Hip scored.  All these are specialist tests, and only the Hip scoring x-rays can be done by your own vet.

It goes without saying for any reputable breeder to want to use him he will ahve ahd to done well at shows and prove himself better than all the other availbable studs. 

Please read the first post on the breeding forum with some other points to consider.

thanks thats helped me loads