I don't know that it's terribly common. I can't say I've run across a single case in 30 years of working with dogs. You might try checking out this web site...they are fairly accurate information here that is meant for the NON VET person to be able to understand with a fair amount of ease. http://www.vetinfo4dogs.com/dogindex.html Here are some additional sites you can check out on topic, via Google... http://www.google.com/search?q=+How+common+is+a+prolapsed+colon+in+dogs%3F&ie=utf-8&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a

I have had 4 in 20 years of raising show dogs. 3 were small puppies, under 8 weeks. What happens is, they have diarrhea,and it inflames the rectum, which then comes out. What the vets do is sew a "purse string" stitch around the rectum, keep the dog on a soft canned dog food until he/she has a bowel movement, then remove the suture. The first 2 times, the puppy was taken to the Operating Room so we didn't see it. The third one we took to the ER Vets since it was at night, and the Vet let us back in the treatment room. We were totally shocked at how the Vet gets the inflammation down in order to be able to "stuff" the rectum back in, before the suture. What they do is take a wash cloth, folded in quarters, very wet. Then they put about a tablespoon of sugar on the wet washrag and work it in a bit, enough to wet but not melt the sugar. They hold this against the rectum and it is not 5 minutes until it has drawn back in on it's own. Apparently the vets want people to think they are doing magic! The 4th one we had, she had gotten into a plant that looks like dandelion, but has prickly leaves. They come up in the spring, and now I pull every one. But her face swole up until her eyes were totally closed, and both her rectum and vagina were protruding. I gave her a Benedryl [l MG per LB of the dog] and rushed her to the ER vets. They told us to go out for supper and she would be ready to go home in 2 hours. I thought no way could it be that soon. It was. They gave her 20 milligrams of prednisone by shot, and eyes were open, rectum and vagina were back in place. All the dogs mentioned were Chinese Shar-Pei. Thanks! Susie