The tail is an important part of the feline anatomy and is actually an extension of the spine. The wagging tail is a communication tool in the feline world, so a cat that doesn't wag his tail is an indication that something might be wrong. Common tail injuries in the cat include abrasions, lacerations, fractured tail, and nerve damage.
Giardiasis is an intestinal infection of man and animals cased by a microscopic protozoan parasite Giardia duodenalis. Giardia is a simple one-celled parasitic species; it is not a "worm", bacteria, or virus. Giardiasis can be an important cause of diarrhea in animals and humans. However, many cats are infected without developing clinical signs or the diarrhea is treated as 'non-specific'.