
In our breed the breeding stock is required to be hip scored and eye tested, so this means in practice they are going to have to be t least 13 -14 months old, depending on how long it takes to get the scores back.
Our boy was used for the first time I think at about 15 or 16 months. certainly it is useful to get a male proven sometime betwen a year and two years, as then even if he hasn't a chance of mating a bitch for a long time he never forgets how. In my breed many males never get a chance to amte a bitch until they are some 5 years plus, and sadly some never do get the hang of it.
I am planning on using a Champion male who has placed in Groups, yet he only sired his first litter last summer at the age of nearly 6 years old. Sometimes no matter how nice the dog there just isn't the bitch that will suit him in himself or his pedigree.