Longhaired kitten turning shorthaired

We have a new experience on our hand. 4 weeks ago we found this kitten that was almost starved to death. He was 400 gr and according to the vets he should have been at least a kg. Otherwise they found nothing wrong with him, and he also seems to be very healthy. He is somewhere between 12-16 weeks old.

The odd thing is that when we found him he was so fluffy and no doubt he was longhaired. Then the last week he has stared to shed all the long fur, but not the short one. Is this normal and will his longhair Return of is he turning into a shorthaired?

One possibility is that because your cat was starving, his body stopped sending nutrition to his coat and so it all fell out, in which case it will grow back quite well once his nourishment catches up with his body's needs. 

Another possibility is seasonal change.  Most longhaired cats get quite shorthaired in the summer.  They shed their long coat and keep just the short one, and sometimes look like they are wearing pajamas.  The longer coat starts to regrow in the fall.  It is the angle of the light, not the temperature, that causes this.  Right now the northern hemisphere is going into fall and the days are getting shorter, and the light angle is lower, so coats are growing, whereas the southern hemisphere is moving towards summer and the days are getting longer and the sun is higher, so those cats will be shedding that longer coat.  You have not put your location in your profile yet so I don't know which hemisphere you live in, but one of these possibilities should work for you. 

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