A healthy cat can be described as having bright shiny eyes, a healthy shiny hair coat, a good appetite, able to maintain their body weight, intermittently playful and generally seems "happy".

However, cats are not always healthy and when they are not, are often very good at hiding their illness just by their nature of survival. They want to appear healthy so they are less vulnerable to predators.

Initial signs and symptoms of cat illness can be subtle and you may have to look closely to see the first clues. Advanced symptoms are generally more obvious.

Many signs of disease are non-specific, suggesting they can be common for many different diseases. Let's look at some common non-specific signs of illness in cats that should worry you and prompt veterinary care and attention:

• Lack of Appetite :
  Anorexia is often one of the first signs of illness in cats. It can be difficult to determine if you feed your cat dry food only and keep the bowl full. For this reason, many veterinarians recommended feeding cats a small amount of canned food, in addition to their dry food, once or twice a day to help evaluate appetite on a routine basis.
  
  

• Less Active :
  Cats that don't feel well are often less active. This is often mistaken for "getting older". If your cat is less active, the safest thing to do is have your vet examine your cat to ensure there are no underlying health issues.
  
  

• Weakness :
  Weakness can be displayed as being less active , being lethargic, or by having a general loss of balance and coordination. All of these are potentially serious signs and should warrant prompt veterinary evaluation.
  
  

• Lethargy :
  Lethargy is a general lack of interest in the environment. It is a very common symptom and can be either and early or late sign of illness depending on the severity.
  
  

• Weight Loss :
  Losing weight is another common sign of disease or illness. Sometimes it is difficult to notice weight loss, especially in longhaired cats. If your cat feels bonier, lighter, or you can easily feel the ribs, this could be a problem and should encourage you to seek veterinary care.