Anemia, Heinz Body in Cats
 
This is a condition in which red blood cells are destroyed. The "Heinz body" can be seen under a microscope. This type of anemia can occur as a reaction to certain medications, or as a result of eating onions. It is more likely to occur in cats than dogs, and is usually caused by something the pet has eaten or drunk. Hyperthyroidism, lymphoma, and diabetes may also bring on this condition.
 
Symptoms
 

Fever
Sudden onset of weakness
Loss of appetite (