Woolblock or hair balls (or trichobezoars, as the condition is known by vets if you really must know) is a common problem in all rabbits, most especially in long-haired breeds. Because rabbits are fastidious animals and groom themselves often they ingest quite a bit of hair. Unlike cats, rabbits are unable to vomit this hair up (now there's an appetizing subject) so it tends to accumulate & cause serious problems. The most common signs of woolblock are:
1) lack of appetite
2) "string-of-pearls" feces or droppings stuck together by hair fibers,
3) lethargy and rough hair coat.
More serious woolblock is evident by very few droppings or those which are much smaller than normal.
In most cases woolblock can be palpated just under the rib cage on the left side of the chest. A normal
stomach will often be difficult to feel or will feel like a small sack of wet sand or putty (unless the rabbit is
terribly chubby, in which case you'll need a crane). with woolblock you'lI feel a more solid mass in this area, which is composed of not only hair, but particles of food interwoven with the hair Next time you pu I a mat out of a rabbit's fur, wet it & try to pull it apart. Not easy! This will give you a good idea of what you'm dealing with. A rabbit with severe wool block is not receiving adequate nutrition & runs the risk of stomach hemorrhage & rupture. Once woolblock has been diagnosed, you have several options for treatment:
Enzyme Therapy, which generally employs enzymes found in papaya (papain) & pineapple (bromelain) to dissolve the woolblock matrix (or interwoven structure). Papain & bromelain don't actually dissolve the hair itself but act on the food particles inside the hairball . Breaking down these particles helps to reduce the size of the hairball, making it easier for the rabbit to pass. Most breeders of long-haired rabbits routinely give papaya tablets or pineapple chunks as a preventative. Nowadays most of the "top of the line" feeds contain papain also.. Most rabbits thoroughly enjoy papaya tablets & can be given 3-5 tablets with their feed for a coupla days at the first sign of Wool Block. Tablets that contain 250 mg papain & 250 mg bromelain are said to be most effective, & can be gotten at health food stores. Pineapple juice (fresh or frozen) can also be given in the water bottle, just be sure to replace it daily. Proteolytic enzyme products like Viokase V, ProZyme & K-Zyme (from vet supply catalogs) are also effective but should not be overused.
Laxative Therapy employs the use of hairball treatments (cat laxatives such as Laxatone or Catalax), mineral oil or Vaseline. Laxative therapy is most effective when used in conjunction with enzyme treatments. The usual dose is 3 cc's (depending on the size of the rabbit) given orally by syringe once daily. Double this dose in more serious cases & continue 3-D days or untill the rabbit shows signs of improvement (regains appetite. droppings increase in size & frequency). f the ranbit has been off its feed for some time or is lethargic you'll have to get more aggressive. Force feed 2 cc's pineapple juice or puree, then 1-2 hours later, 2 cc s laxative twice a day. until it begins to eat again. You may also wish to mix Nutri-Cal into the laxative for added nutrients & calories. (Other laxatives such as Surfak & Colace, from your local pharmacy. have been used with some success. Snip off the end of the capsule & squeeze the contents into a syringe. Give I capsule once daily for 3 days. Do not use either of these with mineral oil as they can cause over-absorption of the oil, block nutrient absorption & upset the intestinal fluid balance.)
Fiber Therapy is best used as a preventative but is helpful when used with the other 2 therapies. This entails replacing or supplementing the usual rabbit feed with high fiber sources. VVhen treating woolblock, move the feed completely & replace with high quality grass hay. The ingested hay fibers form long strands which help prevent the tight interweaving of hair & food. Feed pellets have a tendency to pack together when digested, & hay helps provide space between the the partic es to stop a solid mass from forming. These long hay strands then help "pull" hair & food particles out of the stomach & along the digestive tract. As a preventative, give your rabbits a handful of hay twice a week in addition to their usual ration. Another dietary treatment, a favorite of Angora breeders, is "Gourmet Day". One day a week rabbits are not fed the usual feed but rather birdseed (millets, sunflower seeds, etc.). hay. & whatever greens & fruits the rabbits enjoy. this serves the same purpose as the hay by preventing the formation of a solid mass, & the oil in the seeds acts as a mild laxative. Many rabbits suffering wool block will refuse pellets but will relish this banquet. Many breeders incorporate "Gourmet Day" into their weekly feed schedule.
Another thing to aid to your prevention/treatment program is exercise, which aids proper digestion) &
increases appetite! Let your rabbit hop around your living room, or build a corral in the back yard.(Just make sure the critter's supervised!)
If woolblock is a common or chronic problem (thought to be caused by an unusually small stomach
opening at the pylorus, where it empties into the intestine) you may want to ask your vet for Reglan (metaclo-pramine), an injectable or oral medicine. Reglan increases gut motility, aiding elimination of matter which may have trouble moving through the system.
The very last resort for severe woolblock is surgery, but if you have been observant & diligent in your
efforts it won't come to that. At the first sign of wool block:
I) remove usual feed
2) provide plenty of hay
3) supplement with enzymes
4) give oral laxatives
5) provide space for exercise
6) feed greens & fruits to stimulate appetite. You should see improvement in 3-5 days, but please don't wait until you see a problem to make woolblock therapy part of your rabbit care program! AlI the above can be used on a regular basis for preventative care, & we alI know what prevention is worth!
[Note from AngoraRabbit.com
- Since the date this page was originally published in the mid 1990s, we have
learned that "wool block" may actually be due to a condition known as "gastric
Many Thanks to Lianne Legenza and the staff of "Footnotes" for permission to reprint this information.
Sources for information:
Carpenter. James W. DVM. Ted Mashima. DVM. Edward Gentz. DVM. et. al. "Symposium on Rabbit Medicine" Veterinary Medicine April 1995
Chu. Betty "Woolblock" NARBC Guidebook. 1990
Harriman, Marrinell "Hairballs Prevention and Treatment" House Rabbit Journal
Kilfoyle & Samson "Completely Angora 2nd edition" Ontario 1990
Reed, Dr TE "Fur Blockage in Domestic Rabbits" NlWRC Guidebook, 1992
"Woolblock - No More 'Hit & Miss' Treatment" Domestic Rabbits November/December. 1990
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