It must be ill.
Yes....they are right...the biggest clue to something not being right with a cat is when it will not eat....and there can be a variety of reasons...some very simple...but you need to figure out what is going on with them, because they will starve themselves if something is too wrong. Check the color of your kitties gums...they should be a healthy pink (unless you have one with black gums...then its hard to tell) but they should not look white....that will tell you if your kitty is anemic or not...also, feel his/her ears....are they hot? If they are, there is most likely an infection going on somewhere...are they outside cats or have other inside cats they play/fight with? Check their bodies for any type of scab, scar, missing hair, etc. Many times when cats quit eating, it's because they have an infection or abcess going on somewhere on or in their body. I have two cats who love each other most of the time, but every once in a while will go at each other...and little puncture hole or scratch on the body can turn into an infection...if yu can find it, and pull the scab off so it is ioen and draining, they wil usually take care of it themselves and heal up...if it gets too bad...you will see the swelling...so check your kitties body well. The other most likely time they stop eating is when they get a kidney infection, or get a block in their bladder, and can't urinate. If you notice they are urinating in weird places that are not normal, that's the first sign. Many will try to go somewhere like in the bathtub, where you see the blood in their urine...if this happens, and they quit eating...it's serious....they either have so much inflammation, or a total blockage in their urinary system, that they will become toxic...if your kitty has urinary problems like this, you have, maybe, tops, 72 hours to get something done about it, or you may lose him/her. 24 hours with no eating and no urination is already not good going to critical....
P.S. If it doesn't seem to be urinary related...when you are checking the body, and gums, also check the teeth...a bad or broken tooth, or any tooth infection, will also make them quit eating. (And sorry...that one sentence was supposed to say OPEN and draining)
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