Quotes from the article that the OP found helpful (link provided by another poster in a previous post) http://healthypets.mercola.com/sites/healthypets/archive/2009/12/23/your-pets-anal-glands.aspx
Allergies can Also Irritate Your Pet’s Anal Glands
If your pet is sensitive to ragweeds, grasses, pollens, molds or other allergens in their environment, this can be a problem for their anal glands. All it takes is your pet sitting down outside for those allergens to transfer to the anus and cause overwhelming itching.
So your dog may start to scoot, itch, become red and irritated, and even chew at its rectum, which can create the anal gland problem. So if you’ve got an allergenic pet, addressing the root cause of the allergies is a great way to secondarily address the anal gland problem.
Anal Glands can Also be in the Wrong Spot
Some animals have anal glands that are placed deep and low inside of the rectum. In this case, even though there is healthy stool being passed out of the rectum, there’s not enough pressure to the wayward anal glands to effectively empty their contents during a bowel movement. Very rarely in those situations, those animals have to have anal gland expression performed because they’re not capable of doing it on their own.
