Hair Chewing and Hairballs
(Trichobezoars) |  |
| Rabbits groom themselves constantly, so the stomach contents often contain hair, which is normally passed through the GI tract and excreted with the fecal pellets. The stomach of a healthy rabbit is never empty and the gastric contents often include a large amount of ingested hair. Hair chewing is generally a result of low fiber in the diet and can be corrected by increasing the fiber or feeding hay along with the pellets. Adding magnesium oxide to the diet at 0.25% also may be
helpful. In some cases, hair chewing is a result of boredom. Providing environmental enrichment often halts this abnormal behavior. |
| The hair becomes a problem only if excess amounts are consumed or if it accumulates in the stomach and blocks the pylorus. If this happens, the rabbit becomes anorectic, loses weight, and dies within 3-4 wk. Premortem diagnosis of pyloric obstruction can be difficult, as palpable hairballs can be an incidental finding and radiography is often nondiagnostic. |
| GI hypomotility or gut stasis is the primary concern when presented with clinical illness associated with a hairball. Hairballs are more likely a result of anorexia, not its cause. Gas accumulation creates visceral distention and pain. Decreased food intake and GI hypomotility result in elevation of cecal pH and alteration of cecal microflora, creating cecal dysbiosis. Alterations in water and electrolyte balance result in ketoacidosis and hepatic lipidosis. Gastric ulceration and
gastric rupture may occur. |
| The goals of treatment are to remove the obstruction, stimulate motility, restore GI microorganism balance, and relieve dehydration and anorexia. Treatment includes motility stimulants such as metoclopromide (0.5 mg/kg, PO or SC, tid-qid), fluid therapy, pain medication, and antiulcer therapy. Reestablishment of GI microflora may be assisted by probiotic treatment or cecotrophs from healthy rabbits. |
| Several remedies have been proposed to assist in the break up or passage of a hairball. Pineapple juice contains the digestive enzyme bromelain and has been used to treat early cases of trichobezoars; an adult rabbit is given 10 mL of fresh or frozen juice through a stomach tube or intubation needle, sid-bid for 3 days. Both the fluid and the enzyme help to break up the matrix of the hairball. Canned pineapple juice is not as effective because the
canning process destroys the enzyme. Papaya contains the enzyme papain, also called papayazyme. Papain enzymes do not break down the hair itself, but may help break down the mucus that holds the hairball together. Human health food or nutrition stores carry bromelain and papayazyme supplements as aids to digestion. Mineral oil and laxatives are not effective in removing the hair mass. Roughage (hay or straw) should be fed during the treatment to help carry the hair fibers through the
GI tract and out with the feces. Surgical treatment is certain but risky. |
| Prevention is the best option. Providing a high fiber diet, avoiding stress and obesity, environmental enrichment, and daily combing to remove loose hair effectively prevents this condition. Clinical research does not support routine doses of mineral oil, wetting agents, or proteolytic enzymes as effective preventives. |
