Video narration
Where does a calf begin forming inside a cow? It starts with an egg released from an ovary. During the cow’s reproductive cycle, often about 21 days, an egg is released and, after mating, sperm from the bull enters the cow’s reproductive tract. But mating is only the beginning. The turning point is inside the oviduct, the tube where sperm meets the egg. This meeting is fertilization—the start of a calf. The embryo then travels to the uterus, where it attaches and grows. A cow’s pregnancy lasts about 283 days on average, though it varies by cow and breed. Finally, the calf moves through the cervix, the opening of the uterus, and out through the birth canal. So where does a calf begin? With an egg from the ovary; fertilization happens in the oviduct, growth happens in the uterus, and birth follows through the birth canal.