Our Bella seems to have thinning fur and its usual black color is turning brown. Could this be do to the harsh dry winter air or do you think something else could be going on?

Most likely getting ready to blow coat… If she is eating, sleeping, pooping... then I would not worry too much

I've never heard of that - when mine were changing in the spring the coats would just get "fuzzy" looking and dull - never changed colors.

tris and blacks will sometimes change colors as the undercoat fluffs out. Greyish. Or sometimes with tris there will be some bleeding between the brown and the black during the shed.

Thanks,,,,,,this is our first year with b's and we werent sure what was going on. Thanks again!

Shadow's coat changed to dark brown-yes brown. Then he took pretty well all summer to blow his coat.

I noticed that Daisy (a tri) is also having lighter colors streaked through parts of the black on her back and sides. This is her first whole year in life so this phenomenon is new to me too. Duke's black and white doesn't change, but I notice his shed is usually white.