* Calving is normal: Cows typically give birth to one calf at a time. Having one calf is the standard, not an exception.
* Focus on the calf: In livestock terminology, the focus is often on the calf, not the mother. You might say "a cow that had a single calf" or "a first-calf heifer" (referring to a young female who gave birth for the first time).
Let me know if you have another livestock question!