It makes me lag when animals loads of them are together

Put the summary of the bug you're having here

What I expected to happen was...:to breed lots of animals
Describe what you thought should happen here
Lots of baby animals
*What actually happened was...:*i lagged and my sever disconnected
Describe what happened here
I couldn't stop lagging
Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
2. ...spawn lots of animals
3. ...breed lots of animals