I'm mainly curious.  I have noticed that Lolli likes to have her lips open.  Usually her teeth are close but her lips are open.  Sometimes her mouth is too but mainly it's just her lips.  When I took her in for a wellness check in May, the vet checked her teeth and said they were perfect.  Also, there is no drooling or anything.  So she is very healthy aside from having to keep an eye on her ears for infections.  

I know other animals use their mouths to sense smells and chemicals in the air.  But the only animal that comes to mind right now is tigers.  lol  Does anyone else know if rabbits do the same thing or is this just a little quirk she has?   I am not worried at all.  Just find it a bit funny and am curious.  (She also moves her mouth and smacks a lot which I notice when I'm snuggling with her.)  

Does it kind of look like she's smiling? A friend of mine had a bunny when we were kids and she would always have her mouth open (but teeth together) whenever she was content, I mostly noticed it when she was stretched out and relaxed. It was super cute!

She's not breathing heavily or pointing her nose is she? Just parting the lips enough to show her toofies?
Pip does this on command for me. I say, 'bunny smile' and she comes over and just shows a wee bit of teeth. Of course I have to give her a treat if I ask for her majesty's approval in such a manner.
As long as this isn't accompanied by any other health concerns I'd say it's just a quirk.
How old is Lolli now?

I'd love to see a photo of this! My first rabbit would sometimes have her mouth open just a little bit while sleeping and snoring on her back.

I'm so glad you asked this!!! I was going to post this very same question. My sister has a Jersey Wooly and I started noticing this with him over the weekend. He doesn't do it all the time though. Mostly when he's being petted and loved on. We think maybe he's doing this when he's happy and content? So far no health concerns so I guess it's just a cute little quirk

I've never seen this. Can one or more of you guys catch this in a photo? I'd love to see what you're talking about. Bunnies smiling!

Ok. I will try to get a picture of her Royal Highness. She tends to be a bit elusive with the camera out though.

Sometimes she's hot when she does it. But most of the time, she's just hanging out or I'm holding her. I will check her ears for how hot they are if she seems to be panting. (I'm such an annoying bun mom. lol) I know if she's sniffing something, she'll have her mouth open sometimes so I guess that's part of sensing things.

Lol that is so cute. I know my sister's bun does the same thing when he's looking for attention.

Wooly will show his teeth a little bit when he's pointing his head up to try to meet my hand for pets. I always thought it was involuntary. It would be so cute if he did a smile on command.

Stormy and Olivia do that too, LBJ. It's so cute.