This kind of behavior is common to housecats too - they'll lame a small animal and bring it to their kittens for practice.

Another thing worth noting - most cats like to eat their prey intestines first without caring whether or not it's alive (for pre-digested fiber and other nutrients not common in meat). For larger cats that often hunt by leaping from above and breaking the neck in one stroke the prey will probably be dead, but otherwise they're probably not.