Final answer:
A mature stallion can generally settle about 10-15 mares when hand mated, though this can vary with the stallion's health and management practices.
Step-by-step explanation:
The question relates to the reproductive capacity of a mature stallion in a controlled breeding context, specifically when hand mating. When hand mated, a mature stallion can settle approximately 10-15 mares. It's important to note that this number can vary based on the individual health, stamina, and fertility of the stallion, as well as the management practices in place. However, the typical range provided suggests a moderate level of breeding activity that is sustainable for healthy, mature stallions without overtaxing them or compromising the mares' well-being.