Canine behavior doesn't always translate too well into the human world. If you notice that your dog has a habit of sniffing the Yorkie next door's derriere, don't think of him as a weirdo. In doggie land, sniffing can be a useful tool for simply getting to know another pooch.
When a dog sniffs another dog's rear end, he's often trying to find out more about him, pure and simple. Dogs are adept at smelling with champion noses -- much, much stronger than those of human beings. The canine anal region is home to glands that give off a lot of identifying information about the furry doggie in question. By sniffing a rear end, a dog can gain a lot of new knowledge, from his new friend's gender to his present mood and age -- and then some. Since dogs don't ask each other questions in words, they have to rely on other available streams of information.
By rear-sniffing, male dogs often are able to figure out when exactly female dogs are going to go into heat -- and therefore when they may be open to mating. If your pooch isn't neutered, be careful if you ever notice him sniffing any female dogs' rear ends. He may just have mating on his mind.
The canine act of sniffing rear ends is usually totally harmless. When dogs sniff each others' behinds, they're essentially saying "hello" and trying to get to know the other -- basic efforts to establish friendly relations. If your dog is meeting another canine for the first time, allow him to take a whiff, as it may prevent fighting later on. If two dogs "know" each other and are comfortable being together, maintaining a tranquil environment is usually a lot easier.
Although many dogs respond to being sniffed just fine, not all of them do. Some canines may become irked by the bodily "invasion." If you suspect that another dog is annoyed by your pet's sniffing, separate the pair immediately.
Always check with your veterinarian before changing your pet’s diet, medication, or physical activity routines. This information is not a substitute for a vet’s opinion.