Abnormal breathing?

I've noticed when my little girl is sleeping that her breathing gets kind of funky.. I provided a video of her breathing and was wondering if this was normal or not.. at the end when she moves I'm gently tugging her tail to see if she wakes up, so don't worry, I wasn't pulling hard and I didn't hurt her.

PS. Watch the whole video, near the end is when it starts getting funky.

Sometimes mine do that, and it's either when their dreaming, or their sniffing smells in the air.