Cats changing colour - what it means
Q: The weirdest thing has been happening to our black cat - he has started to turn brown. He's nine years old and a rescue cat that we don't have much history on. Now and again he even leaves some brownish marks on his bed. Is this normal?
A: There are two possibilities here that could explain your cat's apparent colour changes. The first is fleas, or more accurately, flea excrement, which is dark brown/black in colour. It contains haemoglobin from consumed blood, which can stain clothes and bedding dark brown. Check the base of your cat's skin and look for small dark nuggets, picking them up with wet, white tissue. When rubbed between the fingers these should turn a reddish colour. Secondly, many black cats go for the sun-bleached look during the warmer months. This generally changes back to their darker hue as the winter nights begin to draw in and they shed their summer coat for the thicker winter one. If this is the case, your little cat will soon return to the sleek ebony black you remember.
Scott Miller, vet