Connotations of 兔子它爹/兔子的爹?
你比兔子跑得还快 is a common expression, since we all know 兔子 are fast.

他爹 is acting like a 'damn' without cursing.

You run even faster than a damn rabbit.

Another meaning:

Rabbit are fast, the father of rabbit would be treated as faster, this similar expression are very common in Chinese.

Compare 你比老母猪还能吃. to 你比猪还能吃.

A pig mom sounds like 更能吃.