A hairball from a long-haired
Maine Coon
cat (about 4 in/10 cm long).
A
hairball is a collection of
hair or fur formed in the stomach of animals that is occasionally vomited
up when it becomes too big.
Cats are especially
prone to hairball formation since they
groom themselves by licking
their fur leading to hair going into the stomach.
Cattle are
also known to accumulate hairballs, but, as they do not vomit, these are found
usually after death and can grow quite large.
Although uncommon in
humans, some hairballs have been reported, often in young girls as a result of
trichotillomania and pica. In 2003, a 3-year old girl in Red Deer, Alberta,
Canada had a grapefruit-sized hairball surgically removed from her stomach and
in 2004, an 18-year old woman from McAdam, New Brunswick, Canada had a 5-lb
hairball surgically removed from her lower intestine. Hairballs can be quite
hazardous in humans, since hair cannot be digested or passed by the human
gastrointestinal system, and (assuming it is identified) even vomiting
may be ineffective at removing the hair mass. This can result in the general
impairment of the digestive system.