I had a similar situation happen to me, and my nose didnt grow right through development. The septum (the middle wall in your nose) grew to the right side, so one nostril's passage is blocked. Your going to have to get reconstructive surgery to straighten the septum, and possibly remove some flesh material from within the nasal cavity in order to open your nasal passages.
YOU ACTUALLY ONLY BREATHE OUT OF ONE NOSTRIL AT A TIME! TRY THIS OUT - PLACE THE BACK OF YOUR HAND UNDER BOTH NOSTRILS AND BLOW GENTLY THOUGH YOUR NOSE - YOU WILL ONLY FEEL THE BREATH FROM ONE NOSTRIL - TRY IT AGAIN ABOUT 30 MINUTES LATER AND IT WILL HAVE CHANGED TO THE OTHER NOSTRIL!
human breathing is some time fast from first nostril and second nostril from slow. There after some time changing, slow breathing from first nostril and fast breathing from second nostril.
Through its nostril cone.
both can breathe with there mouths closed
Whales Breathe through a blowhole, a modified nostril at the top of their head.
What causes you to breath through only one hole from your nose is the fact that the other hole is blocked by mucus, or "boogers" if the mucus has dried up. If this not the case then you should ask your doctor. Sometimes this is normal. It may be the body's way to get you to turn over in your sleep and prevent bed sores. What happens is that the turbinates in your sinuses swell.
I would say take him/her to the vet. they will tell you if its common or not.
You most likely have a deviated septum.
they breath though the holes or nostrals on their becks
your either sick or allergic to something like dust
With lungs, through a blowhole, a modified nostril on the top of their head.
Whales breathe through a nostril called a "blowhole" on top of their head.