
Thank you very much for your thoughts and experinces, very helpful &interesting.
I do think the breed of a dog makes a big difference.
Some are mature at lot youger so you do know what you are using when they are approx 2 years old.
Some breeds might not have such illnesses that are wide spread and proven to be genetic(but no tests available) and usually show no sign until the magic age of 3-5 years old.
I know in my home country they test sperm pretty frequently and it was exactly what I was going to suggest as a solution on wasting time on mating with a male that ends up being infertile.
One very good reason to me in using a younger male is if the bitch is getting on and can't wait for dog to mature/chance to miss if being mated.
This would also teach the young dog and provide breeders with detail of what that dog produces(if they were to use the dog in few years time WHEN it has matured of course :) ) But then if the bitch herself is older, the status of her siblings is known so at least there is better knowledge of what came of the siblings& bitches previous litters, parents...
I indeed myself have a pup growing up who is from a litter where the male is only 2 years old BUT he has older full siblings(4 years old) and the dam of the litter had 2 litters previously who were 3 and 4 years old. I felt I have enough information provided by relations of the sire/dam to over ride the sires young age.
I have been looking at males that have been used in the past (so I have data of what they have left previously, playing safe :)) so not older maiden dogs anyway.
Also with an older male I feel I know how many litters have been produced and they are unlikely to be used loads more, whereas with a youngster in few years time if the owner is not very selective, every other dog could be related to mine, which I would not like as it would make it difficult to find dogs to continue with.
The main reason why I have decided to select older males to do is indeed because of bad experience :(.
Years ago my bitch was bred at age of 2.5 years, less than a year later she developed AF.
So that litter to me was a waste, I could not continue anywhere from it.
Others did though, which I was very upset about!
I really want to minimise chances of this happening again.
A bitch you have to breed when certain age, with males I hope you can have little more sliding scale and opt for older male who has stayed healthy and the status of siblings/parents is known (as long as people are honest).
So really I am wanting to safeguard the puppies and their owners but also myself in working hard and then being hit by one of these illnesses and having to stop if can't see where the problem comes from or have it too deep in the line of my dogs.