Ovarian cancer

[tonyshuman]

murph72 wrote:

I wonder if supplemental estrogen would also increase cancer rates in rabbits as it has been shown to do in humans? It was a common practice for many years (and, quite frankly still is) to give women in menopause estrogen...now they're linking it to a higher likelihood of breast cancer. Several cancers can be linked to hormonal levels, so I don't expect it to be different in rabbits.

The consensus is that the role of estrogen in promoting cancer in female reproductive organs is hard to determine. Some studies have shown that it promotes uterine cancer, some have shown that it reduces the risk. source: J. Vet. Med. Sci. 69 (9): 981-984, 2007.

"In uterine adenocarcinoma, the incidence increases with age and nearly all breeds can be affected. The carcinogenic effects of estrogens have been implicated in the evolution of uterine cancer [12]. In another study, however, the administration of estrogens to female Dutch rabbits actually reduced the incidence of endometrial adenocarcinomas [2,12]. The role of estrogens in development of this tumor is equivocal. ... However, there is as yet no precise knowledge of the role of estrogen in tumorigenesis of the uterus."
ref 2: Baba, N. and von Haam, E. 1972. Am. J. Pathol. 68: 653-656
ref 12: Percy, D. H. and Barthold, S. W. 2001. pp. 303-306. In Pathology of Laboratory Rodents and Rabbits, 2nd ed. Iowa State Press, Ames.

Sorry I don't have time to chase down these two references for you.

 

[tonyshuman]

Also able to get this abstract, but not the full article:
Uterine adenocorcinoma in the rabbit in contrast to other domestic animals, uterine adenocarcinoma in rabbits is quite common. Within a period of 16 months, 28 patients underwent ovariohysterectomy in the Small Animal Clinic in Frankfurt. In 21 rabbits (which were all more than 3 years old), a uterine adenocarcinoma was diagnosed histologically. Follow-up examinations could be performed in 19 rabbits. Till the 31(th) October 2005 16 rabbits were still alive and in good health. The symptoms of rabbits with uterine adenocarcinoma can vary immensely and can lead to misinterpretation. Abdominal palpation and an X-ray seem to be sufficient for the detection of uterine abnormalties; therefore all rabbits older than 3 years should be examined with respect to a possibly affected uterus. Because of the high incidence of this neoplasm, a preventive ovariohysterctomy should be performed in all female rabbits.

From Streicher, M. Kleintierpraxis 51(6), 309-314: 2006.

This study gives us a value of 75% of rabbits having a uterine adenocarcinoma.

 

[tonyshuman]

All of the studies I'm getting reference that 1958 article by Green, so it must be very well respected. I don't have access to the article at the moment, but I hopefully will within a few days.

More reading, esp. on the role of estrogen in reproductive cancer (in humans as well) http://dels.nas.edu/ilar_n/ilarjournal/45_2/pdfs/v4502cline.pdf

 

[OakRidgeRabbits]

murph72 wrote:

In a study I like to see replication. Who else replicated this study where 80% was found?

Exactly. This "up to 85%" figure is coming from ONE study done over 50 years ago. As we all know even from human research, certain lineages can be prone to cancer and it often runs in families. Who is to say that ALL rabbits are at such a risk as this one person's line...and rabbits outside that specific breed too? I think the guy who did the study had been breeding for something like 30-some years. By then, a line is pretty far linebred, and who knows if that could have had an affect to.

That to me leaves endless inconcistencies. A study must be done over and over, with a sampling of all breeds, all ages, etc. for me to even begin to consider it as fact (or even possibility).

 

[NorthernAutumn]

tonyshuman wrote:

Also able to get this abstract, but not the full article:
Uterine adenocorcinoma in the rabbit in contrast to other domestic animals, uterine adenocarcinoma in rabbits is quite common. Within a period of 16 months, 28 patients underwent ovariohysterectomy in the Small Animal Clinic in Frankfurt. In 21 rabbits (which were all more than 3 years old), a uterine adenocarcinoma was diagnosed histologically. Follow-up examinations could be performed in 19 rabbits. Till the 31(th) October 2005 16 rabbits were still alive and in good health. The symptoms of rabbits with uterine adenocarcinoma can vary immensely and can lead to misinterpretation. Abdominal palpation and an X-ray seem to be sufficient for the detection of uterine abnormalties; therefore all rabbits older than 3 years should be examined with respect to a possibly affected uterus. Because of the high incidence of this neoplasm, a preventive ovariohysterctomy should be performed in all female rabbits.

From Streicher, M. Kleintierpraxis 51(6), 309-314: 2006.

This study gives us a value of 75% of rabbits having a uterine adenocarcinoma.

Thank you so much Claire for doing a journal hunt! Much appreciated.

This study was performed in 2006.

Surprisingly, many of the drugs and treatments that you receive have been around for a shorter period of time than the earliest studies of tumours existing in rabbit uteruses.
However, we consume those drugs with confidence.

As those articles point out, there have been multiple studies done since that time on the topic.

(As an aside, Watson and Crick's theory of DNA arrangement was the very first of its kind, and it was highly accurate for its time.)

I don't think it makes sense to negate all of the research since 1958 that concurs with the trend.


The 2006 study shows 75% occurence of tumours in utereus after age 3
(^The difference between 75-85% is pretty small beans.)

***Again, just because a tumor shows up, doesn't mean it is cancerous. They are only talking about the presence of tumours.

Just because you haven't experienced cancerous complications in your does doesn't mean that a tumor of some form doesn't exist.
Just means that the tumors present in your does are not cancerous .


(Which means, both these breeders and the studies agree )

 

[Maureen Las]

http://www.vin.com/VINDBPub/SearchPB/Proceedings/PR05000/PR00404.htm

http://www.radil.missouri.edu/info/dora/RABBPAGE/neo.htm#II.


http://www.peteducation.com/article.cfm?c=18+1803&aid=2147

http://homepage.mac.com/mattocks/morfz/BBcancer.html

http://www.vet2pet.co.uk/pethealth/rabbithealth/uterinecancer_rabbit.asp

http://www.kanin.org/node/182

http://bunnyluv.org/bunnyfacts_new.htm

Most of these were written by veterinarians . I don't need a research article (although you can find some in the references at the last page of several articles. )

I also don't need a % rate

Ijust need to read what I just posted.....

 

[murph72]

I guess I'll have some reading to do...boy! Coincidentally I just returned from an American Cancer Society function. There has been a far greater amount of studies done on cancer in humans --obviously. I can say that, in my opinion, there has not been enough studies done on rabbits to come to any kind of real conclusion. In the studies on humans they have found definite genetic links. I for one battle melonoma. I was originally not considered a "candidate" for this disease as it was not in my family history. Now every member of my family is looked at by dermatologists because I am the family history. They tell you there is a genetic tie to melonoma and that it comes from sun exposure. Certain people are genetically predisposed to it. I am one of those and I have had melonoma where the sun never shined. My mother had breast cancer (also the first in the family for what is supposed to be genetic) due to the use of estrogen supplements for less than a year. The genetic tie is there in people as I'm sure it is in pets. When looking at the rabbits who have contracted these cancers a family study would also need to take place to rule out genetics as the cause...which is a point that OakRidge also made. As cancer researchersare looking heavily at genetic and environmental causes, this should also be the direction for those in the veterinary field studying cancer rates in rabbits.

Samantha, I am glad I do not know the breeder who culls his bucks and does at three years of age. He and I obviously do not have the same view of rabbits. Some of my best bucks and does are older than three when they become better at what they're doing. I just bred a doe the other day that it was her first time. I gave her to a young buck twice and she didn't take to him. It took putting in my more experience older buck to get the job done right. I also don't see the bunnies I get attached to as expendable. What is this man doing with these rabbits? Does he give them away as pets? Does he sell them to another breeder after he deems them unfit? I see your point to spaying and neutering, but in my area spaying is truly not safe yet. We don't all live in areas that have rabbit-savvy vets. It would also cost an arm and a leg if I did convice one of the vets to do it, and I'm not sure it would be a good gamble.

Many of my older does have lived to be close to ten years old. I have only lost one doe to cancer and it started asliver cancer. Saying that the other does that have died had cancer but died from complications brought on by the cancer is like taking a stab in the dark.I have lost does to all sorts of problems, and many of them could never have been linked back to cancer. Did they have cancer when they died of something completely unrelated? Hey, maybe. Did it start necessarily in the uterus, hey, maybe not. Will the cancer elsewhere move to the uterus? Yes. Definitely. It will also move to many other areas the lymph system and veins will move it to.

 

[bunnybunbunb]

He sold them to breeders. He always told, at least me, their problems if any. Mostly it was "I just sell them at 3 years old, however they can breed longer".

I am in rural kentucky, you think we have many rabbit savvy vets here? Nope. I have found one. The one was a *cough* but this lady is good. But at $200 a spay it would take me months to be able to afford it if I needed to spay someone again.

 

[murph72]

I still can't imagine he doesn't get any more attached to his rabbits than that. I have a hard time selling an adult rabbit even if I know it is going to a good home if I've already bonded with it. Some rabbits it's easier than others, but I can't imagine doing it with all of them...but maybe I'm too soft.

I tried to get two females spayed a few years ago...maybe five now. The normal vet I go to for my cats won't even see rabbits. The two that do see rabbits refuse to do a spay, only a neuter. The vet I take my rabbits to sent me to what they called a specialist that was over an hour away. When I got there he informed me he'd only do the spay in the case of emergency. It seems the last bunny he spayed was his daughter's and it died on the table.

If I look on the list of "rabbit savvy vets" the closest one is over three hours from me. That would be over a six hour trip in the car for the bunny. I just don't think that's safe for them. They scare so easily sometimes. I could probably talk my vet that just tried to spay my Sweet Pea to try another...but I'm afraid they will die just like she did. I think he only tried her because we thought there was no other choice and he honestly wanted the experience. I'm not sure I can hand him a healthy rabbit and ask him to spay. Perhaps that makes me a coward, but I'd rather take my chances with the cancer threat.

 

[OakRidgeRabbits]

murph72 wrote:

I still can't imagine he doesn't get any more attached to his rabbits than that.

It's not so much that one doesn't get attached or love their rabbits any less than someone else. A person who is dedicated to their breed just realizes that they must keep the herd moving in order to improve. You can't just have 20+ useless (in the breeding sense) does sitting around for 7-10 more years!

Most breeders will move on older breeding stock by the age of 2 or 3 at a discounted price. That usually gives the new owner a few more litters out of them before the rabbit has to be petted out. Then at around 4, they are sold as a pet.Rabbits usually live a whole lot longer than 4, so most people don't mind "adopting" older show rabbits from breeders.

 

[bunnybunbunb]

I just had an almost arguement with two breeders on facebook about selling to petstores. They do not feel they have a responcibility to the rabbits they produce that is not "good enough" for them. I disagree and *cough* sure do not want to be put in the same book as them, as a breeder. I take in rescues and rehome them. Any pet bunnies that are born will stay until found proper homes. If that means my breeding needs to be put on hold for cage space then so be it, it is MY responsibility to the rabbits -I- brought into the world.

I get very attached, and it makes breeding hard due to keeping space for breeding stock and growing out.

The vet I currently use is not on the list but she seems very knowledgable. She said she has been doing rabbit spays/neuters for at least 7+ years which I find amazing since I know vets who have been vets for 20+ years and have never done a rabbit desextion. She is not only up on medicine ok for rabbits, she was very willing to vgive Metacam which the vet who did's Becca's spay was not, but she knows nutrition and diet needs. She was very friendly and talked for a good 20 minutes to us. I like her and she is only 40-50 minutes away.

 

[tonyshuman]

murph72 wrote:

I tried to get two females spayed a few years ago...maybe five now. The normal vet I go to for my cats won't even see rabbits. The two that do see rabbits refuse to do a spay, only a neuter. The vet I take my rabbits to sent me to what they called a specialist that was over an hour away. When I got there he informed me he'd only do the spay in the case of emergency. It seems the last bunny he spayed was his daughter's and it died on the table.

If I look on the list of "rabbit savvy vets" the closest one is over three hours from me. That would be over a six hour trip in the car for the bunny. I just don't think that's safe for them. They scare so easily sometimes. I could probably talk my vet that just tried to spay my Sweet Pea to try another...but I'm afraid they will die just like she did. I think he only tried her because we thought there was no other choice and he honestly wanted the experience. I'm not sure I can hand him a healthy rabbit and ask him to spay. Perhaps that makes me a coward, but I'd rather take my chances with the cancer threat.

It's too bad there aren't any really rabbit-savvy vets near you. It sounds like the rabbit specialist you see isn't very experienced with rabbits, as it is very rare for rabbits to die from improper anesthesia, and errors in the surgery (especially the kind that lead to death) are also very rare. I am lucky to live in a modest-sized city with many rabbit-savvy vets, and a vet school, all of which do spays. The shelter vets even will do them for $40, if you demonstrate financial need I think. They are very successful at the shelter, spaying even older females (age 3-7) that come in.

I have heard on this forum of several bunnies that had uterine cancer, and that scares me. Most of the older unspayed females seem to get it, from my experience in the Infirmary. It just scares me because it's so easy for them to hide the cancer until it's too late to really do anything, and it has metastasized to other organs.

Also, my bunnies are sassy and smelly enough that I don't think I'd want to deal with the hormones of an unspayed doe.

Re: the car ride, my guys regularly go with us on trips. We just went to MI last weekend, which took 8.5hrs on the way there, and 7 on the way back. We also go to GA about 2x a year, which is a 12+ hr drive, and they just sleep most of the time (Muffin gets a bit bothered). I would only worry about surgery complications. Being so far away, if something happened it would be difficult to get help. I think the drive would be fine for her, unless she's one of those bunnies that totally freaks out in the car, but you might want to stay nearby for a night at a pet-friendly hotel to make sure she recovers from surgery ok before making the trip back home.

 

[murph72]

OakRidge, I also breed, but there are certain does that I keep with me until they pass. I live on a 42 acre farm, so it's usually only an issue of making a cage to house a bunny in if it's a space issue. There are some that I have sold as pets and others that I decide I no longer need for my breeding program, so they go to other breeders. However, I do not specifically look at a doe and say, "Oh, you're 3 so I need to move you down the road." I will keep a doe as long as she is an asset to the breeding program...but I will also keep bunnies that I consider to be my favorites. I got into the hobby because I love the personalities, so it would be a shame to not keep the ones whose personalities are also my favorites. The only time they move on to other homes is if it is to a personal friend who also loves them as much as I do.

Samantha, you are lucky to have a good rabbit vet so close. I was talking to my friend who is located in a more rural area than even I am. She thinks I'm lucky because my vet will actually listen to me and wants to learn. I guess we all look at others who have it better off than we do...it's all relative. Unfortunately, spaying in my area is far too risky as of yet. On one hand I want to give the vet the opportunity to try spaying, but I hate to give him a healthy rabbit to do it on if it means I may lose them. I'm not sure I'm willing to make that gamble with their lives on the operating table.

Claire, The does that I'd have spayed are not used to car rides as I donot show a doe that has been bred. If she was ever in a car, it would have been early in her life. I also would be afraid of complications and then I'd be so far from home. In addition, Ithink it's best for the bunny to return to a familiar place after such a surgery and a hotel certainly wouldn't be that. Then there's the cost involved. I think my husband would kill me if I started carting bunnies on a six hour trip to be spayed at the cost of hundreds of dollars. The hobby is expensive as it is -- wow would that be a huge expense to swallow on top of it. I'm afraid he'd tell me it was time to close up shop. You are right about them hiding their cancer. My doe that had liver cancer hid it like a real champ. The only sign was that she was not as nimble at hopping up on things as she had been, but at first I credited that to her getting older. When I took her in to the vet for the first time and she died so quickly for them they were shocked since she had looked so good. The necropsy revealed cancer throughout her. The vet said it was amazing that nobody saw any signs since she had it so thoroughly.

 

[OakRidgeRabbits]

murph72 wrote:

OakRidge, I also breed, but there are certain does that I keep with me until they pass. I live on a 42 acre farm, so it's usually only an issue of making a cage to house a bunny in if it's a space issue. There are some that I have sold as pets and others that I decide I no longer need for my breeding program, so they go to other breeders. However, I do not specifically look at a doe and say, "Oh, you're 3 so I need to move you down the road." I will keep a doe as long as she is an asset to the breeding program...but I will also keep bunnies that I consider to be my favorites. I got into the hobby because I love the personalities, so it would be a shame to not keep the ones whose personalities are also my favorites. The only time they move on to other homes is if it is to a personal friend who also loves them as much as I do.

Right, I'm not saying that I look at a doe and immediately kick her out at any certain age too. I was just saying that it would not be practical to keep each and every breeding rabbit until they pass naturally. It would be a setback as a breeder, and it is also a benefit to the rabbit itself. What bun wouldn't love to spend its last years as a spoiled house bun, ya know?

I just had an almost arguement with two breeders on facebook about selling to petstores.

By "petting out", I didn't necessarily mean pet store. That just means to sell as a pet, rather than breeding stock. I have a different view of pet stores, but that's kind of another topic. Whatever you decide to do with your pet bunnies is fine, I just meant retiring them to a pet home, one way or another.