How can I use telepathic bond on a donkey?

So, my character has a donkey. I’d like my donkey to be 3 smart, so that I can use telepathic bond to talk to it.

There aren’t stats for donkeys. There are stats for various horses, and for mules, and even for a wooden donkey; all have an intelligence of 2. That makes a great argument for saying that a donkey is 2 smart. Of course, a @#%# cat is 3 smart, and I am pretty sure my donkey is smarter than any stupid old cat. But how to convince the DM? Are there any in-game statistics or comparisons that I’ve overlooked that support assigning a donkey an intelligence of 3?

Failing that, is there there a way to give my 2 smart donkey a boost to 3? I have searched, but I’m not coming up with anything. Some sort of elixr of smartness? Temporary would be nice, so that I don’t have to put up with a smart ass all the time.