okay so it really does make a difference on the litter and he needs to be "cleaned out" prior to breeding since he has never "let loose" before???? I've got people telling me all kinds of stuff and 99% is sarcasm so im not sure who to listen to here!!
No, it does not matter if he's not been bred before, I've used several first timers, two were one tie only, based upon progesterone, and resulted in 9 and 11 puppies. The only thing is not knowing if his sperm is any good since he's not been used yet. Nothing wrong with getting his semen checked beforehand if you have a repro vet who can do a count and motility check, but I would not make collecting him a regular practice until he's learned to be a good "natural" stud. Sometimes, males who only get collected don't learn how to handle a real bitch, they expect human help, and turn into real duds for studs for live cover.