The minimum age for breeding any female is 1 1/2 years or their third heat, whichever comes first. That is a standard age for any breed. The males can begin breeding as soon as they start producing sperm which can be from 7 to 10 months.
The beagle is and old breed of dog. They were, and still are today, used as hunting dogs.
The beagle has been around for a while but there are new " variations" of beagles according to the akc.