Cat has developed a course coat

Question
I have a neutered male cat about 5 years old that I adopted as a kitten from a
rescue organization. In the last couple of months he has developed a really
coarse coat.  Is this a symptom of something serious?  There are no hot spots,
he does not scratch, no baldness or excessive hair loss. He doesn't seem to feel
bad. Have two other cats and they are fine.  Is it vet and expensive blood test
time?

Answer
I don't think it's that time yet, Carol. Sounds to me like he's shedding into a cooler summer coat. He may be doing this for the first time in his life, or it may simply be more coarse this time.

The coarser the coat, the more air gets to the skin, thus keeping your cat cooler. If he is bigger now than he has ever been, recently had a growth spurt, or gained more than 2 pounds since last summer, his body could have decided to change his coat to help him stay cooler.

Continue to monitor him for scratching, hair loss, hot spots, or redness, and I think you should be in the clear.