John,

Situated on either side of the anus are two anal glands. These glands
manufacture a foul smelling material that is normally expressed when your
cat has a bowel movement. These glands can become painfully blocked and
infected. Impacted glands do not affect the overall health of the pet. The
problem is that, pets may injure the anal area when scooting across the
ground, or discharge the secretion on the carpet or floor. This material has
a terrible odor; this is possibly the material that is causing the foul
smelling matted hair near the rear end, and the film that you are wiping
away. This is a rather normal occurring event on a cat of your age. Your vet
will be able to show you how to deal with the situation. If you wait to see
your vet, the anal glands may become abscesses and must be lanced by a
veterinarian, thus your cat will then be on antibiotics. You can try to use
a warm compress on the area. This often helps to relieve some of the pain.
Once you get the situation rectified, you may want to put your cat on a high
fiber diet. The high fiber makes the cats stool more bulky. The stool will
put more pressure on the anal glands and hopefully the glands will express
themselves when the cat defecates. Cats may also be supplemented with bran
or psyllium husk, which will increase the bulk of the stool. Feeding your
pet raw bones can also help. I hope this helps.

Her anal glands probably need emptying is my guess.  (If so, the vet will do
it.)

Cathy

--
"Staccato signals of constant information..."
("The Boy in the Bubble")  Paul Simon

Could be anal sac disease - impaction, infection, or abscess.  Actually, all
three are probably a continuous process.  IOW,  impacted anal sacs tend to
become inflamed and infected > infection can then lead to abscessation.
However, anal sac disease in cats usually only involves impaction and
possibly infection which are easily treated by manual expression and
antibiotics.

The anal sacs are usually naturally expressed when the cat poops.  However,
if your cat is eating primarily dry food,  much of the water she drinks
contributes to fecal moisture - which can soften the stools a little to much
in some cats.  Cats fed canned food have higher urine volumes (which is a
good thing) and lose less water to fecal moisture so that the stools are a
little firmer which helps express the anal sacs naturally.

If the provlem is anal sac disease, you might want to speak to your vet
about gradually switching her over to canned food once the immediate problem
is treated and resolved.

See:

http://www.maxshouse.com/anal_sac_disease_in_the_cat.htm

Good luck,

Phil

Sounds like your cat has clogged anal glands.  A vet will take care of it.