The two arguements against feeding cats raw eggs are the same as for feeding
humans raw eggs:

1) The glycoprotein named avadin in the uncooked "white" part binds to and
prevents absorption of the biotin found in the yolk. It is a known fact that
this not only results in nonabsorption of the yolk's biotin, but if this
practice is a regular and frequent part of the diet, then it will eventually
result in a biotin deficiency unless biotin suppements are given/taken.

2) It is believed that there is a high enough probability of salmonella
infection resulting from consumption of raw eggs, that the healthy benefits
of eating them do not warrant the risk of being poisoned by salmonella.

Some people believe that with regards to #1 that there is more than enough
biotin in the yolk to offset the bind-up losses due to avadin. This belief
is a fallacy. Dr. Sharma, PhD, who is a biochemist with Bayer says that 5.7
grams of biotin are required to neutralize all the avidin found in the raw
whites of an average-sized egg. But there are only about 25 micrograms (25
millionths of a gram) of biotin in an average egg yolk.

So for practical purposes this leaves the consumption of raw yolks (only) as
a remaining possibility.

The probability of a salmonella infection from the consumption of raw egg
yolk can be reduced to a safe and extremely improbable level if the
following advice is practiced:

A. Healthy chickens in healthy environments don't contract/transmit
salmonella. So the risk virtually disappears with high quality, cage free,
organically fed, omega-3 enhanced chicken eggs.

B. Follow the raw egg handling and inspection tips at
http://www.mercola.com/2002/nov/13/eggs.htm Note: Mercola was wrong about
his baseless unfactual statement concerning the adequate content of biotin
in egg yolk. He later took that back in a follow-up article published this
year.

C. Liquid grapefruit seed (not grape seed) extract can be diluted in water
and used as a naturally excellent salmonella-cide. Such a dilute solution
can be used as a disinfecting bath for the external surfaces of any number
of unopened egg shells; where the germs will likely be, if present at all.