If you're asking about fishes, the offspring may be uncountable.
Reindeer usually have one calf at a time.
rabbits can have as many babies as posibble but it is unfair to make them have too many !
one at a time usually
usually one at a time.
Usually one or rarely two.
The penguin species usually have only one offspring per couple.
Usually only one.
Usually one.
They usually have up to 3-6.
They usually have up to 3-6.
two is how many they usually have, but they sometimes have three.
There are usually 2-6 in a litter, but there can be as many as 8.