My name is Jane. I have worked with animals professionally for over 17 years dealing with both health and behavioral issues. I have over 14,000 satisfied customers. It will be my pleasure to work with you today. .
I'm not a big fan on anal gland removal myself. I've seen dogs develop fecal incontinence with this, but your vet knows your dog, so you may want to discuss this possibility with your vet. The polyp may be in an area that makes removing the glands a good choice especially given the anal gland issues that are already present.. What I would question is if the polyps may be the reason that your dog's anal glands don't express naturally with firm bowel movements. I do want to give you a good site that goes over Anal sacculectomy and things that you will want to know before having the surgery done.
He probably does have discomfort in the area and with the anal gland issue alone he would likely be looking at his rear. You will probably need to contain him after surgery to prevent him dragging his rear on the ground. I'd also be prepared with a no bite collar or e-collar to prevent him licking and irritating the area during recovery. I like the no bite collars because they are less disruptive and seem to work pretty good at stopping chewing at the hind quarters. Here is a site that has them.
The following page will also help you understand diseases and problems of the rectal area.
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