To determine if the rabbit is male or female I am thinking it can be two options:
1.A male/female symbol on bottom right corner of rabbit picture
2. When you hover your mouse over the rabbit instead of: rabbit, quality 10 It could be: male/female rabbit, quality 10 (well you get the idea)
The breeding system can be something like this:
While theres male and female in the rabbit cage female will get pregnant for .... hours/weeks and when the pregnancy is over the female rabbit will give birth to 7-9 little rabbits (you will have to leave place around the rabbit, in other case the rabbit whont give birth).
That way the breeding system will be balanced whit chicken's as well keeping it unique.
Tell me what you think

P.S. Used search function didn't found that this was already suggested, in other case please forgive me
