Here's why:
* Gestation Period: Cows have a gestation period of about 283 days (9 months). During this time, they are carrying a calf and are physiologically unable to conceive again.
* Hormonal Changes: During pregnancy, a cow's body produces hormones that prevent ovulation (the release of an egg). This ensures that she can focus on developing the calf she's already carrying.
* Reproductive Cycle: After giving birth, a cow goes through a period of postpartum recovery, before her reproductive cycle resumes. This cycle typically involves a period of estrus (heat) when she is fertile and can become pregnant again.
Therefore, cows can only become pregnant again after they have given birth and their reproductive cycle has resumed.