When animals become anemic, their ability to absorb oxygen from the air and deliver it to tissues in the body is severely impaired, which can cause a variety of problems, but is most commonly manifested as weakness and lethargy. In severe cases, it will also result in the increased respiratory effort as the animal attempts to increase the amount of oxygen in the lungs in order to improve the level of oxygen in the circulation.
Untreated, anemia can be a debilitating disease, and in severe cases, it can be fatal. Cats, unfortunately, are predisposed to developing anemia. This is due in part to the fact that their RBCs have a shorter lifespan (around 70 days) than many other animals (around 110-120 days in dogs and humans), which means they have a higher turnover of RBCs and anemia can develop quite quickly if anything interferes with this. Cats are also susceptible to a variety of diseases and infections that can result in anemia.
