Why do dog dogs smell each other’s fart first when they see the little partner? Is it really its special habit?

I used to think that this was a dog checking the gender and then sexual behavior. Later, I gradually realized that this was a special way of greeting. When we see others for the first time, we will introduce ourselves or exchange business cards, and then we will remember some of their personal information and physical characteristics. On the other hand, dogs remember each other through a sense of smell. There is anal gland in the dog’s hips.
The special substances secreted by the gland, which are secreted with the dog’s feces, some of which are retained in the anus. Each dog secretes different odors, and this smell represents each other’s names or codes in the interaction between dogs and dogs. Similarly, dogs also want to know each other more in a relationship, but at the same time want to protect their privacy. So you sometimes see the two dogs sniffing each other’s ass, one of which is trying to cover your smell by pinching his tail or avoiding sexual behavior.
It -like people, they want more and more information about each other, but they definitely want to keep their secrets. Many people understand it as two dogs greeted each other when they met, but not just that. In the anus glands, in addition to moisturizing the anus, it is actually equivalent to ID cards and databases. It contains a lot of information about dogs, including dogs, living standards, and recent living conditions.
Although these odors are unacceptable to humans, they are attractive for dogs, and they are important ways to communicate with dogs. Why do two dogs often ask this question when they often meet? Because these smells change with factors such as diet, living standards, and environment, the smell produces will be different, and the spread of information will be different. Many dogs like to smell each other’s butt when they meet, but what’s good about stinky buttocks? I don’t think the dog will think so. They seem to be very interested in the smell of the buttocks. Large dogs, small dogs, male dogs and female dogs will travel long. So what are the things that are worth smelling on the buttocks?

Because the identity of the other party can be determined through the smell, it may be caused by the reason for estrus, not a special habit.