pregnant cat losing fur

Question
I have a pregnant blue tortie point siamese cat, and a male sealpoint.  I have 3 questions.  First of all they are both 10 months old and we got them from a breeder.  She said we had up to a year to have them fixed before they mate, and we had an appointment booked with the vet but we discovered it was too late. Our girl was pregnant.  We did not want to abort the kittens.  Here is my question 1 and 2.  At 10 months old is she too young to have kittens?  They were from the same breeder, who at the time had 16 kittens from 3 different Dams.  What if it turns out these kittens are brother and sister?  Will the kittens be deformed?  We desperately wants her to have healthy kittens.  We have her on the same diet.  Iams, Maxcat and friskies all mixed together just like the breeder gave us and they are still on kitten food.  They also get a can of soft food to share once a day.   Our female cat Is losing her fur around her tail and on her lower back, I suspect she got pregnant around 2nd week of December, and have noticed the fur loss just after new years.  What could cause this?  Is it normal in pregnancy?  Our male cat is perfectly fine.  Here are a few changes I gave seafood soft food.  (I usually stick to chicken and beef with gravy.)  The holiday season bustle.  Could it be stress?  Or could it be something else.  I also have a yellow lab but his skin coat is fine as well.  They do not have fleas, so what could it be?  I should mention that they are strictly indoor cats.  

Answer
Hello, there.  Let's see if I can help.

Q.  At 10 months old is she too young to have kittens?

A.   Ideally, cats should be a year old before they're bred, but 10 months isn't usually anything to worry about with a Siamese.  They mature sexually younger than most cats, often at six months.  As long as she is otherwise healthy, I wouldn't be too concerned.

Q.  What if it turns out these kittens are brother and sister?  Will the kittens be deformed?  

A.  As long as they are the first generation to be inbred, then chances are highly unlikely there will be anything wrong with the kittens.  Deformities usually start to arise with the second or third generation of inbreeding.

Q.  Our female cat Is losing her fur around her tail and on her lower back, I suspect she got pregnant around 2nd week of December, and have noticed the fur loss just after new years.  What could cause this?  Is it normal in pregnancy?  

A.  It isn't normal during pregnancy.  However, hormonal changes that occur during pregnancy can do some crazy things, and hair loss might be related to this.  There's a condition called stud tail, named this because unneutered males get it most often, which is usually related to hormones.  Excess oil is produced and causes blocked pores, greasy fur and hair loss at the base of the tail.  Female cats can get it as well.  It's usually not harmful, and washing the area with a liquid handwashing dish soap, or using a chlorhexidine scrub (available online and at some pet stores) can help dry the area and lessen symptoms.

Q.  Could it be stress?  Or could it be something else.  

A.  It certainly could be holiday stress.  Siamese may be predisposed to anxiety.  Generally, this will resolve on its own within two months after the root cause is gone.  Those who suffer longer than that may be candidates for an antidepressant (I'm not sure, but I'm guessing these would probably be a bad idea until the kittens are weaned).

But fish is also more commonly allergenic than chicken or beef, so it is possible she's got itchy skin because of an allergic reaction.  If you're still feeding them fish, I would discontinue that, just in case.

Q.  They do not have fleas, so what could it be?  

A.  It could be a number of things.  Since they don't go outdoors, things like mange mites aren't very likely.  However, it could be a bacterial infection, such as staph, or a fungal infection, like ringworm.  Ringworm usually causes a round rash, but there are certainly cases that don't always fit that description.

Best thing would be to ask a vet.  It would be wise to have a physical done with a pregnant cat, anyway.  I also have an x-ray done around the 6th or 7th week of pregnancy with my cats, to determine how many kittens we're expecting.  That way you can tell if there are any complications during delivery.  It's hard to be certain if all the kittens have been delivered otherwise.  Having an undelivered kitten can threaten the mother's life within a day.