Dog's anal glands - bad smell - Answered by Dr. Slome
These are likely anal gland substance that he is secreting monthly - it IS really putrid. Some dogs get infections of these glands and cause them to build up content more quickly. Other dogs just have it periodically and there is nothing wrong. This is a natural repellant which is also a unique smell to each dog ( that is why dog's smell each others behinds). Sometimes people have these glands surgically removed if there is a chronic reoccuring infection or they just can't stand the smell.
Sorry. You can also try and get an animal odour eliminator from your veterinarian which at least will neutralise the smell within short time when sprayed on the anus area.
Martin Slome DVM
Centre Street Animal Hospital
7700 Bathurst Street Units, 40-42
Tel. (905) 771-9855