The mare's reproductive system includes ovaries that produce eggs and hormones, oviducts that carry eggs to the uterus, and a uterus for gestation. In the stallion, the testes produce sperm and hormones, which travel through the epididymis and vas deferens during sperm maturation and are ejaculated through the urethra and penis during copulation. Both male and female reproductive cycles aim to produce offspring through fertilization and gestation.