There are several reasons, some more serious than others, that can explain why you dog’s behind may smell bad.
Perhaps it has a lot of gas? Or does it have diarrhoea? Check your dog’s next stool. You can give it active charcoal and montmorillonite food supplements. Be cautious, and if despite taking these food supplements, or if your dog’s health is suffering (fatigue, loss of appetite), you should seek help from your veterinarian.
Urinary and faecal incontinence can also be the cause of unpleasant smells. Another illness that can be the cause of losses in the area and thus of strong smells is pyometra for females. This infection of the uterus is considered a veterinarian emergency. All three of those conditions require veterinarian attention.
Finally, it is possible that your dog has released the content of its anal glands, after a stressful situation for instance. These glands, located on each side of the anus, secrete a foul smelling liquid that enables dogs to mark their territories. You can use a no-rinse shampoo to clean the area.
To get rid of unbearable smells in the room where your companion is, you can use an odour destroyer.
