In general terms, a very young cow is called a calf. If it's female, then it is called a heifer calf. If it is male, then it's a bull calf. If the calf has been castrated (by humans of course), then it's called a steer calf.
A baby elephant is called a calf, like a baby cow A calf. A young elephant is called a calf. Elephants are considered social animals and normally give birth after a gestation period of 12 months. The young one of an elephant is called a calf.