Breeding dogs: the tie - dog breed info center®, dbic, Breeding dogs: the tie. male dogs can start to have sperm at seven months old, but ten months is more common. young dogs do not have quality sperm.. The 3 most aggressive dog breeds revealed! – pit bulls, With breed specific legislation acts being brought forward in more and more areas across the country, dogs like pit bulls, rottweilers, doberman pinschers and other.