Upper respiratory allergies and inflammation and swelling of the adenoids, the tissue at the back of the nose, can cause poor fluid drainage from the middle ear to the external ear and therefore cause a blockage in the Eustachian tube. Excess fluid can lead to middle ear congestion.
1 Black skin and Asian skin have thicker and more compact dermis than white skin. This is also why blacks and Asians have fewer facial wrinkles than whites. 2  Black skin has more casual lipids and more moisture in the stratum corneum than white skin.  Black skin has 50% lower ceramides than white or Hispanic skin.
An ebony chinchilla can come in different shades of black; from solid black to light greyish-black. A heterozygous ebony carries one ebony gene and they can be light to medium black. The belly is dark and should not have any white on it. A homozygous ebony carries two ebony genes and is often dark to extra dark ebony. black velvet chinchilla has a dark veiling of black over the top of the body with a crisp white belly. This color variety carries the Touch of Velvet gene. The TOV gene means that the animal has a dark veiling over the top and a lighter underbelly.