---------------------------------------------------------------------------- http://www.extremezone.com/~colovin/BHRR/spay.html Brambley Hedge Rabbit rescue recommends spaying and neutering all pet rabbits. Altered pets are healthier. An unspayed female rabbit stands a 70% to 80% chance she will be inflicted with uterine cancer. Female rabbits should be spayed at 6 months of age. Male rabbits also benefit from neutering, making them less prone to behavioral problems, such as aggression and territorialism (spraying). male rabbits should be neutered at 4 months of age. Unfortunately our grant monies from Petsmart, for low-cost spay neuter vouchers has run out. Please check back or contact the vets on our referral page for prices. ---------------------------------------------------------------------------- http://www.sonic.net/~snevel/etherbun/msg08966.html * Date: Thu, 21 Jan 1999 20:25:32 PST * From: "Lanny Purnama" * Subject: Re: spay a live-alone female? Hi Donna, > She is my only bun so I am wondering if I should have her spayed or > not. Are there any benefits that would make this worth the risk of > surgery? Yes, of course. The spay surgery is especially beneficial for female bunny because most female rabbits if not spayed sometimes in her life (usually 2 yrs) will develop uterine cancer. This is the main reason why females need the spay surgery. Also, by spaying her, it will help her litterbox habit and her behavior since it reduces her hormone level. > Also, I am having trouble finding a vet in my area who is experienced > in bunny care. I live in Port St. Lucie, Florida. Please check out this page to see if this referral is close to your home: http://www.rabbit.org/care/vets.html#Florida > The vets I have contacted are willing to "give it a go" on the surgery > (that alone makes me nervous...yikes!) and quote me a fee of $150. Is > that about right as the going rate? Please make sure that the surgeon is a rabbit vet. If not, better not take the risk. And about the $150, yes it's reasonable for spaying. I spayed my Tweety for $200, and it was 2 years ago. And now, with her perfect behavior and her affection, it worth all that money and more. Good luck! Lanny- http://scf.usc.edu/~purnama/tweetybunny.html ---------------------------------------------------------------------------- http://www.sonic.net/~snevel/etherbun/msg08974.html * Date: Thu, 21 Jan 1999 21:31:08 -0600 * From: Bonnie Jean Weinman * Subject: Re: spay a live-alone female? Hi Donna For a good Rabbit Vet, look at the HRS - http://www.rabbit.org - site. Here's an excerpt from an article on neuter/spay from the HRS. Hope it helps. Corinne from Bucky's Bunny Barn said that, in a study done by him, Greene found 79.1% of does over a certain age had UC (uterine cancer), she thinks it was 5 or 6 yrs. BJ Why Should rabbits be spayed or neutered? Altered rabbits are healthier and live longer than unaltered rabbits. The risk of reproductive cancers (ovarian, uterine, mammarian) for an unspayed female rabbit stands at is virtually eliminated by spaying your female rabbit. Your neutered male rabbit will live longer as well, given that he won't be tempted to fight with other animals (rabbits, cats, etc.) due to his sexual aggression. Altered rabbits make better companions. They are calmer, more loving, and dependable once the undeniable urge to mate has been removed. In addition, rabbits are less prone to destructive (chewing, digging) and aggressive (biting, lunging, circling, growling) behavior after surgery. Avoidance of obnoxious behavior. Unneutered male rabbits spray, and both males and females are much easier to litter train, and much more reliably trained, after they have been altered. Altered rabbits won't contribute to the problem of overpopulation of rabbits. Over 15 million adorable dogs, cats, and rabbits are killed in animal shelters in this country every year. In addition, unwanted rabbits are often abandoned in fields, parks, or on city streets to fend for themselves, where they suffer from starvation, sickness, and are easy prey to other animals or traffic accidents. Those rabbits who are sold to pet stores don't necessarily fare any better, as pet stores sell pets to anyone with the money to buy, and don't check on what kind of home they will go to. Many of these rabbits will be sold as snake food, or as a pet for a small child who will soon "outgrow" the rabbit. Altered rabbits can safely have a friend to play with. Rabbits are social animals and enjoy the company of other rabbits. But unless your rabbit is altered, he or she cannot have a friend, either of the opposite sex, or the same sex, due to sexual and aggressive behaviors triggered by hormones. Spaying and neutering for rabbits has become a safe procedure when performed by experienced rabbit veterinarians. The House Rabbit Society has had over 1000 rabbits spayed or neutered with approximately .1% mortality due to anesthesia. A knowledgeable rabbit veterinarian can spay or neuter your rabbit with very little risk to a healthy rabbit. Don't allow a veterinarian with little or no experience with rabbits to spay or neuter your rabbit. URTHEMOON@aol.com wrote: > Hi folks, > > A newbie to bunnydom here. I have a 10 month old dwarf bunny named gb > (goofy bunny). She is my only bun so I am wondering if I should have > her spayed or not. Are there any benefits that would make this worth > the risk of surgery? > > Also, I am having trouble finding a vet in my area who is experienced > in bunny care. I live in Port St. Lucie, Florida. If anyone in my > area can refer me to a knowledgable vet I would appreciate it...or > perhaps a resource where I can find a list of bunny-qualified vets in > my area? The vets I have contacted are willing to "give it a go" on the > surgery (that alone makes me nervous...yikes!) and quote me a fee of > $150. Is that about right as the going rate? > > Thanks for the help. > > Donna and gb > > Donna, "You're going to love these aromatic herbs, gb" > gb, "To heck with that stuff, just give me my carrots!" ---------------------------------------------------------------------------- http://www.whiskerwisdom.com/spayor.htm Spay Or Neuter My Rabbit??!! Spay or Neuter my Rabbit?! by Dana Krempels Without question! Your rabbit will reach sexual maturity anywhere between the age of 3 to 8 months. Once the hormones start flowing, expect to see behavioral changes. Some might be cute, and others unpleasant. A rabbit reaching sexual maturity can be expected to exhibit: * loss of good litter box habits * aggressive lunging and biting * territorial biting/nipping * growling * circling and honking * destructive chewing * spraying urine * destructive digging Because un-altered rabbits often mount one another endlessly due to sexual frustration (and to establish dominance), same sex pairs who tolerated each other as babies will often begin ferocious fighting upon reaching sexual maturity. This can result in very serious injury. Opposite sex pairs will begin reproducing as soon as they mature. In one year, a single pair of rabbits and their un-altered offspring are capable of producing more than 2000 rabbits! You may think you can find homes for your bunny's babies, but we have seen far too many abandoned and dumped pets to think that this is a realistic hope. And for every one produced by a casual breeder, another is put to death at an animal shelter, because there are simply not enough homes for all of them. Unspayed female rabbits have a very high risk of uterine, ovarian and mammary cancers. Some reports state that more than 80% of unspayed female rabbits will develop uterine/ovarian cancer by the age of three years. Upon reaching sexual maturity, male rabbits often begin displaying mounting behavior (on your shoes, the cat, stuffed toys, your leg, your sleeping head...), marking territory with urine and producing a pungent odor. Testicular cancer, while less often reported, does occur in males. How can spaying/neutering help? 1. Rabbits who are spayed (females) or neutered (males) are much less likely to display unpleasant hormonally-induced behaviors.. 2. Rabbits who are spayed or neutered produce less odor, due to lower sex hormone levels. 3. Rabbits who are spayed/neutered and housed indoors live much longer than those who are not. "Intact" rabbits live an average of three to six years. The average spayed/neutered house rabbit lives 7.9 years. Many live 10 years or more. (The record is 18 years!) 4. Rabbits who have been spayed/neutered can live with a rabbit companion of the opposite sex without the danger of unwanted litters. Rabbits of the same sex can more easily learn to get along without fighting. Rabbits are highly social, affectionate creatures, and they thrive in the company of other rabbits. (These must be carefully introduced, to avoid fighting. The safest option is to allow your rabbit to choose his/her own partner from your local rabbit rescuer, since most rabbits are very choosy about the company they keep!). 5. Rabbits who are spayed/neutered will never contribute to the terrible domestic rabbit overpopulation problem. Thousands of rabbits are abandoned every year, when they outgrow their Easter Bunny cuteness. You will never have to worry if your rabbits offspring will suffer a terrible death after being abandoned in the wilds of suburbia, being dumped at a pet store to be sold as snake food or being euthanized at an animal shelter if you don't contribute to this problem. And just so you know.... 1. Spaying/neutering your companion will NOT make him/her "fat and lazy." Lack of exercise, wrong foods and boredom will do that. 2. Your rabbit's endearing qualities will NOT change. His/her unacceptable, hormonally induced behaviors usually will. The earlier you spay/neuter (3-5 months for males, 5-8 months for females), the less changes you will notice in your rabbit's behavior. 3. Our domestic rabbits (Oryctolagus cuniculus) are derived from an ancient line of the wild European rabbit. European rabbits live in warrens (a series of underground tunnels excavated by family groups) in an established territory. A domestic rabbit who has been abandoned in a park that looks inviting and safe to a human has been sentenced to a cruel death: s/he has no warren in which to hide from predators or from the elements; s/he has no family, and if there are resident feral rabbits in the area, s/he will most likely be attacked ferociously because she is not a member of the warren. If s/he survives the threat of predators, cars, humans running their dogs and other immediate dangers, s/he will soon succumb to parasites, disease and starvation. Turning a rabbit loose in a wild area is not much different from turning a human loose, naked, in the most dangerous neighborhood in town. Don't consign your rabbit friend to such a fate. ** A DOMESTIC RABBIT depends on human care. S/he will die if set loose, no matter how appealing the environment appears to a human. ** PLEASE don't abandon your bunny to "the wild" OR to a shelter or pet store, when he or she matures into an adult. Give him or her a fair chance to be a true companion. You will experience one of the most delightful, intelligent, loyal, affectionate and entertaining friends you will ever know! ** THOUSANDS of these wonderful companion animals are euthanized yearly. Be a part of the solution to pet overpopulation and unnecessary euthanasia. ** SPAY OR NEUTER YOUR COMPANION RABBITS! Bunny will be healthier. Everyone will be happier! [Image] for the life of your rabbit! ---------------------------------------------------------------------------- http://www.geocities.com/Heartland/Ranch/8093/whyspay.html Why Should I Spay or Neuter My Rabbit? (reprinted courtesy of Bunny Bliss, PO Box 4156, Oceanside, CA 92055) There are many myths and concerns about spaying or neutering your rabbit. Some of the myths are: 1.My rabbit will become fat and lazy. This is not true. Altering your rabbit does not make your pet fat or lazy. Too much food and not enough exercise are the causes of obesity. 2.A female should have one litter. Not true. It is actually better for her not to have a litter. 3.I will be able to find good homes for all the babies. You may be able to place your bunnies, but will they go to good and permanent homes? Each time you place a bunny from your litter, somewhere a bunny is killed because there was no home. Yearly, thousands of adorable, adoptable rabbits are destroyed at animal shelters because no one wants them. Thousands more are abandoned in fiends and road sides to suffer and die. You may have no trouble finding homes for your adorable babies, but who will care for them once they outgrow their cute bunny phase and the novelty wears off? Once spayed or neutered, rabbits can live over ten years. They are not just a temporary pet. The unfortunate fact is there are many more wonderful rabbits than there are wonderful long-term permanent homes for them. Facts you should know... * an unspayed females has an 80% chance of developing uterine or ovarian cancer between two and five years of age. * Rabbits are induced ovulators, which occurs only after sexual activity has occurred. Rabbits do not "go into heat" in the standard dog or cat sense. * Rabbits can become pregnant immediately after giving birth. With a gestation period of about 30 days, one female can produce as many as 12 litters per year. A stressed over-bred mother may re-absorb the fetuses or eat the newborns. * Altering your rabbits rids you of the worry of what to do with unplanned litters of bunnies, eliminating all of the problems and potential risks involved in pregnancy and birth. * Reduces aggression against other animals, decreasing fights, thus saving expensive veterinary bills and aggravation. More reasons to spay or neuter... * Most people are unfamiliar with rabbit behavior and may feel their cute little bunny turned into the "Rabbit from Hell". When a female rabbit matures, she MAY become very aggressive and may circle and spray just as males do. She may bite and start frenzied digging (which may be into your carpet). This behavior goes away when she is spayed. * Unfortunately, so many rabbits are given up between the ages of six months and one year, because owners don't know that what their rabbit is experiencing is normal and not fun for the rabbit. There is an answer...spay and neuter! General Rules to Follow... The smaller breeds of rabbits up to the size of Holland Lops mature at about 3 ½ months of age. The larger breeds, such as Flemish Giants, mature around 5 to 7 months. Medium sized breeds mature somewhere in between. Aggressive behavior and negative sexual activity will lessen in about two weeks after surgery. The larger breeds may take from four to eight months before signs of negative activity diminish. Keep in mind males are still viable for about 2 weeks after surgery. After this time has passed, neutered couples can live together and may occasionally mount each other. This is normal. Neutering your rabbit is the best gift you can give him. It will make him a better companion and someone you and your children can hold and love. Rabbits are very special animals. If you have never lived with one, your life will be changed forever. They are interesting, curious, loyal and very affectionate. Because they give us so much we owe it to them to learn everything we can so that they can live long and happy lives. Locating a veterinarian that specializes in rabbit care in addition to dogs and cats is the first step, spaying or neutering your rabbit is the next and finally, just love and care for them each day. House Rabbit Resource Network PO Box 33364 Austin, Texas 78764-3364 (512) 444-3277 E-mail: HRRN@hotmail.com ---------------------------------------------------------------------------- http://www.mahouserabbit.org/guestbook/guestbook.html Anne Frazer Brockton, Mass windsymp@aol.com Comments: I just lost my beloved Angelica, a gorgeous minilop, to uterine cancer very suddenly last weekend. She was only 3 years old and we all miss her. I know she will always be in our hearts and in due time we will find another bunny to spoil and love as she would want us to do. The vet was quite surprised that this occurred in a rabbit of only 3 years. PLEASE don't hesitate or wait; spay your bunnies so that you don't have this happen to you. ---------------------------------------------------------------------------- http://www.rabbit.org/chapters/san-diego/health/vet-talk/spay_neuter.html San Diego Chapter, House Rabbit Society Spaying and neutering your pet rabbit: What happens and why? There are many good reasons to spay or neuter your rabbit, not the least of which are medical, though they may not be as obvious as the behavioral and population control benefits. Female rabbits, especially those who do not breed, seem to have a high risk of developing uterine cancer. One study found 75 percent of a population of female New Zealand White rabbits had uterine cancer by the age of six years. We have diagnosed uterine cancer in rabbits as young as 18 months of age, and see a very high occurrence of the cancer in rabbits over three. Male rabbits are at risk of developing testicular cancer in their later years, although the risk is not as great as that of uterine cancer in females. Several diseases involve the male reproductive tract and others are transmitted by sexual intercourse. Knowing the benefits of having your pet spayed or neutered should be balanced with the risks or complications of the surgery. Rabbit anatomy and physiology are different than in other pet animals, making the surgeries, in some ways, more difficult. The personality of a rabbit may also make him or her less suited for surgery. Anatomy and physiology The reproductive tract of the female rabbit is unusual compared to the dog or cat. The uterus is bicornate, which means that it is composed of "two horns." Each uterine horn possesses a cervix. (There is no uterine body as is present in a woman's uterus). The region is more fragile than in other species: The tissues of and supporting the uterus tear easily when handled during surgery. These supporting tissues also act as the female rabbit's principal fat-storage site, which makes it more difficult than in other species to identify and tie off blood vessels supplying the area. The male rabbit's anatomy is similar to that of other mammals, except that the testicles move freely from the scrotum to the abdomen through an open inguinal canal. The rabbit patient The behavior of rabbits has a strong influence on their suitability as candidates for surgery. Rabbits are timid and submissive. Their desire to return to health diminishes with fear or pain. Not uncommonly, rabbits may stop eating, even to the point of starvation, following surgery. Rabbits are fractious and may struggle violently if frightened. Improper restraint can lead to fractured limbs or spine. Moreover, a frightened rabbit may produce so much catecholamine [adrenaline-like hormones related to fear] as to seriously affect anesthesia. Sometimes it may be necessary to postpone surgery until a preexisting problem is resolved or until the rabbit is calmer. Ovariohysterectomy (spay) Prior to surgery, the rabbit is anesthetized and her bladder emptied by gentle palpation. Her abdomen is shaved and washed, and she is positioned on the surgery table lying on her back, draped with sterile cloths. A 2- to 3-cm. incision is made in the skin between the umbilicus (the belly button) and the cranial rim of the pubis bone. The incision is continued into the abdomen along the narrow "linea alba" where the abdominal muscles come together, using great care not to damage the intestines or cecum. The uterus, found just under the urinary bladder, is lifted through the incision, followed by the oviduct and infundibulum, which are coiled in a large loop several times longer than that of a dog or a cat. The blood supply to the ovary is double ligated; then the uterus and its blood supply are ligated just caudal to the cervices. Care must be taken not to contaminate the abdomen with urine or the contents of the vagina. The uterine vessels stand off the uterus several millimeters and can be of significant size in mature females. These must be double ligated so they will not bleed. Then, the uterus is removed and the abdomen closed in three layers--the abdominal wall, the subcutaneous tissues and finally the skin, which is often closed with staples. The rabbit should be confined and observed for complications, such as bleeding from a slipped ligature. Orchidectomy (castration) The rabbit is anesthetized and positioned on his back. The hair is carefully shaved from the scrotum and surrounding area, and the region is cleansed and draped. An incision is made through the skin of the scrotum and the vaginal tunic, an inner sac containing the testicle. The testicle is removed from the tunic and the ligament that attaches it to the scrotum is carefully torn. The testis is then pulled to expose a section of the vas deferens and the vascular structures of the spermatic cord. These structures are ligated and the testicle is removed; the process is repeated for the remaining testicle. The rabbit should be observed for several hours for the presence of hemorrhage. Complications have most often resulted from over activity, or sexual activity, prompting the author to hospitalize these patients overnight for "cage rest." Semen remains in accessory tissues left in the male rabbit allowing the rabbit to be fertile for many weeks after the surgery. There are anecdotal reports of neutered rabbits fathering bunnies as much as 6 weeks after surgery. It is recommended that newly castrated rabbits be separated from fertile females for 6 to 8 weeks after the surgery. by Jeffrey R. Jenkins, DVM ---------------------------------------------------------------------------- http://www.geocities.com/Heartland/Valley/1155/UC.html UTERINE CANCER IN RABBITS Below is an article I've written about uterine cancer that should help sort out the scientific information available and referred to on the internet. The article was written for the breeder and as a short introduction to the subject. Some additional information is presented after the article, just some additional book references and statements from people that should also help your understanding of the subject. As I get additional information about UC in rabbits it will be presented on the site. Uterine Cancer In Rabbits I would bet many of you reading this have never experienced uterine cancer in your herd. Therefore it is understandable that many breeders doubt the information passed out by many rabbit rescue groups, especially when they throw figures out such as 85% of all unspayed does will get uterine cancer. The veterinarian community is also mute on the subject, some cite book references but do not share their experiences with us. I had my doubts about the high incidence of uterine cancer and set out to find the facts about it. I wish to share what I have learned with all of you in order to better the knowledge of the breeding community. Uterine cancer is the most studied form and most common of cancers found in rabbits. Many studies have found incidence rates of 1.3%-2.6%, The Biology of Laboratory Rabbits report studies finding numbers such as 16 rabbits with cancer out of 599, 4 in 150, 2 from 400 (1). It appears there is a low incidence of uterine cancer in these studies however the rabbits in these studies were juveniles and not considered old enough to be "cancer-prone". TBLR reports that most rabbits used in research colonies are between 4 and 24 months of age. Cancer occurrence in younger populations is normally a low amount. Harry S. Greene spent years researching cancer in rabbits and his findings are the source of the infamous 80% figures for uterine cancer incidence. He studied a colony for 30 years and his findings reveal a significant incidence of uterine cancer in older does. "Greene reported that 16.7% of 849 female rabbits (dying of various causes) were found to have uterine adenocarcinoma (Greene, 1958a)." (1). When one examines uterine cancer in the age groups we find the incidence increases with age. Greene reported an incidence of 4.2% in does 2-3 years of age and 79.1% in those 5-6 years old. Other researchers have also found similar results in aged rabbits. "Notwithstanding heredity as a factor, the incidence of uterine carcinoma has been noted to exceed 50% in certain colonies of random-bred females kept past age 5-6 years." (1). Dr Barbara Deeb DVM in Washington state reported that in her practice among spay surgeries she performed during 1994-1996, she found 9 out of 16 does over 3 years of age with adenocarcinoma (56.3%). In does 1-3 years old it was 6 out of 37 (16.2%), however 9 (24.3%) in that group had endometrial hyperplasia (precursor to uterine cancer). Does under 1 year of age had no occurrence of uterine cancer, but 4 out of 77 had endometrial hyperplasia. (2). A pet owner on the Petbunny mailing list has been tracking incidence of uterine cancer among house rabbits. She has a survey pet owners fill out and she is keeping records based on it. The last update appeared in September of 1997, she had records on a total of 209 rabbits with the average age of 2.9 years. The total incidence is 14%, but does over 3 years old have an incidence of 40% (24 out of 60). Does 1-3 years old have an incidence of 3.2%. There were a total of 18 does over 6 years of age and 8 had uterine cancer (44.4%). This information suggests the occurrence of uterine cancer is much greater than many of us have experienced. Greene also found that reproductive problems occur in the does prior to tumor detection (3). The reproductive disturbances he reports include: diminished fertility, reduced litter sizes and many dead young, retention of litters, abortion, or resorption. In one fourth of the uterine cancer cases cystic breast changes were also observed. He also found that the incidence vary in relation to age, breed, and other constitutional factors (3). "No instance of the tumor occurred in the Belgian or Rex breeds, and the arrangement of breeds in order of increasing incidence stands as follows: Polish, Himalayan, Sable, Beveren, Chinchilla, English, Marten, Dutch, Havana, French Silver, and Tan." (3). Another interesting note from Greene is that crossbred animals had a total of 21.1% incidence while purebreds had 14.2%. The crossbreds were kept because they showed or transmitted "constitutional variations" while the purebreds were considered "normal". Greene also found that there was a link between pregnancy toxemia and eventual development of uterine cancer (3). Apparently tissue changes and blood chemical alterations were the same in fatal cases of pregnancy toxemia as "mild" cases. All animals experiencing toxemia later developed uterine cancer. This is the link between endometrial hyperplasia and uterine cancer, it always preceded the development of a tumor in the studies. Greene's paper goes on to suggest that liver function is affected by pregnancy toxemia and can last up to a year. During this time the inability of the liver to suppress estrogen could ultimately result in tumors. As responsible breeders we should be sure to warn any pet owners who buy a rabbit from us that has had a history of problems, they would be at great risk of developing uterine cancer. Also of interest is that carcinoma of the cervix in rabbits is apparently non-existent. Greene's laboratory searched for it during autopsies of almost 4,000 does over 2 years of age but didn't find a single case (3). Greene says there is an anatomical basis for this. Although no one has reported "the" incidence of cancer among the general population of rabbits, pet or breeder, we should pay attention to what the studies are showing us. Adams (1962) made the observation that the incidence of uterine cancer in breeder rabbits and aged virgin rabbits was the same. Many breeders do not keep their does past breeding age and often will not keep does around who have reproduction difficulties, so this may explain why many have not experienced the incidence. I believe there is enough evidence to support the position that there is a significant risk of uterine cancer in older female rabbits. I believe it is our responsibility to inform pet owners of it and to promote spay and neutering of all pet rabbits. In addition to removing any risk of uterine cancer it also provides a behavioral benefit. Many people who abandon a pet rabbit do so because of hormone driven behavior such as spraying, aggression, and mounting, however spay/neuter can often prevent or lessen these problems. References: 1) The Biology of Laboratory Rabbits 2nd Ed 1994, Manning, Ringler, Newcomer 2) March 1997 Veterinary Conference in CA Rabbit Medicine and Procedures for Practitioners Program and Abstracts "Neoplasia in Rabbits" pg. 171. 3) Adenocarcinoma of the Uterine Fundus In the Rabbit by Harry S. N. Greene pg. 535-542, Annals New York Academy of Sciences. ADDITIONAL NOTES: Domestic Rabbits May/June 1991 pub. by ARBA, "Medical and Surgical Care of the Pet Rabbit" by Robert C Clipsham DVM. The article mentioned that uterine cancer was one of the most common forms of cancer in rabbits. Ovahysterectomy (spaying) was mentioned as preventative care for does not destined for breeding. As a benefit it also helps to lower what the author referred to as "the very high rate of endometritis and endometriosis documented". It was also mentioned that these reproductive disorders account for a lower expected lifespan for rabbits (6 yrs vs a potential of 15 yrs.) From e-mail conversations with an experienced rabbit vet, I found out he sees an estimated 20% incidence of uterine cancer in his practice and he does most spays at 5 months of age. He also said that he has read several articles that cite incidence rates of between 14%-35%. He also told me that the mortality rate for spay surgeries should be less than 1% and that he has never lost a doe so far. I have read other sources they state a mortality rate should be less than 1%. The UC survey Suzy Shaker is conducting can be found at : http://www.earthlink.net/~suzys/survey.html I recommend all pet owners fill it out because that will be the best way we can come up with an estimate of the incidence of uterine cancer in does. As of 10/8/98 Suzy Shaker's survey is reporting the following information: Rabbits diagnosed with cancer 13% 42 out of 320-this is all ages Rabbits over age 2 diagnosed with cancer: 31% 37 out of 120 over age 4 43% 22 out of 51 over age 6 50% 11 out of 22 I urge all owners of does to fill out this survey, it is likely that this survey will be the most comprehensive look at uterine cancer in rabbits and can be another important key to determining whether or not you spay your pet rabbit. The decision to spay or not is up to you but it is important you research all the factors and talk to your veterinarian. I hope you have found the information on my site helpful in your decision. Personally I recommend spaying for pet rabbits because it will eliminate the possibility of your doe having cancer and there is a behavioral benefit. Just be sure you go to an experienced rabbit vet who has a good (or non-existent) mortality rate for the surgery. ---------------------------------------------------------------------------- http://www.rabbit.org/care/bibliography.html Pine/Cedar Shaving Toxicity 1. Rabbit Health Newsletter (Nov. 1991) cites U.S. Dept. of Health and Human Services, National Institutes of Health pamphlet No. 86-23 titled "Guide for the Care and use of Laboratory Animals" A quote is listed as saying: "Aromatic hydrocarbons from cedar and pine bedding materials can induce the biosynthesis of hepatic microsomal enzymes (Vesell, 1967; Vesell, et al., 1976; Cunliffe-Beamer et al. 1981. Uterine Cancer 1. Toft, J. D. 1992. Commonly observed spontaneous neoplasms in rabbits, rats, guinea pigs, hamsters, and gerbils. Semin. Avian Exotic Pet Med 1:80. 2. The Biology of the Laboratory Rabbit, 1994 edition. TBLR provides the following information. Adenocarcinoma of the uterus is the most frequently encountered neoplasm of the rabbit. Ingalls (J. Natl. Cancer Inst. 33:799-806. 1964) showed that 11 of 12 rabbits developed uterine carcinoma. Because of the number of rabbits developing carcinoma many researchers looked into the possibility of estrogen being carcinogenic. There was quite a bit of conflicting data, and the authors draw this conclusion "Data is extremely difficult to interpret because of the naturally high incidence of adenocarcinoma of the uterus in untreated rabbits." Later, "Notwithstanding heredity as a factor, the incidence of uterine carcinoma has been noted to exceed 50% in certain colonies of random bred females kept past 5-6 years." 3. Ann NY Acad. Sci. 75:535-542 Green, 1958. This is perhaps the best article, and probably where everyone gets the often quoted 80% figure. Greene monitored a colony of rabbits over a long period of time (8-10 years). All rabbits dying from whatever causes were necropsied. 16.7% of 849 rabbits were found to have uterine adenocarcinoma. The average age of the colony was greater than 4 years, which is important, because most lab rabbits are under 24 months of age. The tumor incidence in Greene's colony was very closely linked to age. In rabbits dying between 2 and 3 years of age the incidence of cancer was 4.2%. In rabbits 5-6 years of age the incidence is 79.1% (the mythical 80%). Note: these rabbits did not necessarily DIE from the cancer, but there were tumors after their death. We don't know what the different causes of death were, but they are listed as "natural". The incidence of cancer in males and females is about the same in rabbits under two years of age, after that, the incidence in females dramatically increases over the males, primarily due to uterine cancer. We found the article in _TBLR_ because it was referenced in a journal that claimed that the incidence of cancer was somewhere between 1 and 4% in rabbits. That low figure was compiled from laboratory rabbits, most under 2 years of age. So, that figure agrees very well with Greene's findings. When one starts looking at older rabbits the data drastically changes. Most of the veterinarians we've talked with seem to believe that this is very genetically controlled. _TBLR_ even lists breeds that are not susceptible to uterine cancer. While 80% may not be a figure for all rabbits, it was for that colony. Other colonies have had >50% incidence of cancer. Many thanks to Laura Tessmer for researching the topic of uterine cancer. ---------------------------------------------------------------------------- http://www.magpage.com/~laurat/petbunny/spay.html PetBunny Discussion List: Uterine adenocarcinoma in female rabbits Written by Laura Tessmer laurat@magpage.com Regarding uterine cancer in female rabbits, a quick run to _The Biology of the Laboratory Rabbit, 1994 edition_ (TBLR) pops up the following information. Adenocarcinoma of the uterus is the most frequently encountered neoplasm of the rabbit. Ingalls (J. Natl. Cancer Inst. 33:799-806. 1964) showed that 11 of 12 rabbits developed uterine carcinoma. Because of the number of rabbits developing carcinoma many researchers looked into the possibility of estrogen being carcinogenic (because of the high levels of estrogen constantly in a mature rabbit's system). There was quite a bit of conflicting data, and the authors draw this conclusion "Data is extremely difficult to interpret because of the naturally high incidence of adenocarcinoma of the uterus in untreated rabbits." Later the reviewer writes, "Notwithstanding heredity as a factor, the incidence of uterine carcinoma has been noted to exceed 50% in certain colonies of random bred females kept past 5-6 years." Perhaps the best article (and probably where everyone gets the 80% figure that's been quoted over and over) was publised by Green in 1958 (Ann NY Acad. Sci. 75:535-542). Greene monitored a colony of rabbits over a long period of time (8-10 years, I think). All rabbits dying from whatever causes were necropsied. 16.7% of 849 rabbits were found to have uterine adenocarcinoma. The average age of the colony was greater than 4 years, which is important, because most lab rabbits are under 24 months of age. A very important finding was tight correlation between tumor incidence and age in Greene's colony. In rabbits dying between 2 and 3 years of age the incidence of cancer was 4.2%. In rabbits 5-6 years of age the incidence is 79.1% (the mythical 80%). Note: these rabbits did not necessarily DIE from the cancer, but there were tumors found in the uterus during necropsy. I don't know what the different causes of death were, but they are listed as "natural". The incidence of cancer in males and females is about the same in rabbits under two years of age, after that, the incidence in females dramatically increases over the males, primarily due to uterine cancer. From talking with various vets and animal health people, it seems that some people don't believe cancer is a problem and others do. I happen to be one that believes it. I found the article in _TBLR_ because it was referenced in a journal article discussing cancer in rabbits which claimed that the incidence of cancer was somewhere between 1 and 4% in rabbits (I don't remember the exact figure). Not believing it, I checked. That low figure was compiled from laboratory rabbits, most under 2 years of age. However, that figure agrees very well with Greene's findings, that there is a very low incidence of cancer in young rabbits. When one starts looking at older rabbits the data drastically changes. Most of the vets I've talked to seem to believe that this is a genetically controlled trait. _TBLR_ even lists breeds that are not susceptible to uterine cancer (A list I hesitate to reproduce because I'm not sure how true it is). While 80% may not be a figure for the rabbit population in general, it was for that colony, composed of genetically diverse animals. Other people have reported colonies with a >50% incidence of cancer. The threat is real, and is acknowledged by the veterinary and scientific community who have worked with rabbits, particularly older rabbits. I've talked to vets who say it's not, but all of the veterinarians who I would trust to touch my animals do view it as a real risk. Last Modified July 6, 1997 Laura Tessmer http://www.magpage.com/~laurat/petbunny/spay.html laurat@magpage.com ---------------------------------------------------------------------------- http://home.earthlink.net/~suzys/results.html Spay Survey Results Last updated Oct. 8, 1998 Total number of rabbits = 320 Averagre age = 2.9 yrs The "age" column is the age of the rabbit if unspayed or the age of the rabbit when spayed (at which time the risk of uterine cancer is removed). Number of rabbits age (yrs) Total Diagnosed with cancer Died from cancer 0-1 140 2 0 1-2 59 1 0 2-3 41 4 1 3-4 28 11 3 4-5 18 6 3 5-6 11 5 3 6-7 2 2 2 7-8 11 4 1 8-9 4 1 1 >9 5 4 4 Percentage of rabbits diagnosed with cancer = 13% (42 out of 320) Percentage of rabbits over age 2 diagnosed with cancer = 31% (37 out of 120) Percentage of rabbits over age 4 diagnosed with cancer = 43% (22 out of 51) Percentage of rabbits over age 6 diagnosed with cancer = 50% (11 out of 22) Please note: This is an ongoing survey and each rabbit is assigned an ID number when her information is recorded. You can update the information for a particular rabbit (for example, if she has been spayed since the survey was filled out) by completing another survey or sending me an e-mail. Please include your name and the rabbits name. ----------------------------------------------------------------------------