
Just to add generally an owner of a good dog will allow his dog to be used by suitable bitches, it is in fact the bitch owner that makes the decision to ask to use a dog :D
There are Champions in my own and other breeds that have never sired a litter as they were not chosen for one reason or another as suitable/compatible to sire puppies to the bit6ches that brteeders were going to breed from.
As you migh5t imagine a bitch owner has the choice of the tope dogs in the country, so are not going to use an unproven dog they have never seen when they can use one whose progeny they have seen and evaluated, and who has proven himself in the showring or working arena.
Also any health tests rtequired for the breed must also be carried out.