Maine Coon Cats

Question
We have a 12 year old Maine Coon (deaf) solid white cat with amber eyes.  Beautiful.  Never been outdoors.  In the past year, he begs for tuna and salmon when I'm preparing it.  I noticed that it stopped him from vomiting hairballs, so I started giving him a little everyday.  Problem:  he has lost all the hair on his chest.  His pink skin and nipples are very visible when he lies down.  Is this old age?  Or too much mercury?  He's not losing hair any other place.  Thanks.

Answer
Hi Kathy.  Too much tuna is very bad for a cat.  Not only does it increase the mercury in their systems to an alarming level, but it is known to cause urinary crystals, and in male cats, that causes a urinary tract blockage.
I would definitely stop giving tuna everyday.  It's okay to give tuna as a treat once in a while, but everyday is too much.  I would see if cutting back the tuna improves the hair loss condition.  If not, I would definitely recommend a vet visit, as hairloss is a key symptom to Hyperthyroidism.
For hairballs, try Kitty Malt.  It's sold in pet stores and comes in a pump tube.  I have always found this to be a great help!  
Please let me know how he does!
Hilary