Chicken's ass and duck's ass are the places where lymph glands are concentrated, because macrophages in lymph glands can swallow germs and viruses, even carcinogens, but they can't decompose them, so toxins will precipitate at the tip of the ass. Over time, the chicken tip has become a big warehouse for storing viruses and germs.
Extended data
Chicken taboo:
First, the neck of a chicken is inedible.
This part of the meat is less, but the blood vessels and lymph glands are relatively concentrated. It's no problem to have something to eat once in a while. It is best to remove the skin when eating, because some detoxification glands such as lymph are concentrated in the subcutaneous fat of the neck. These glands contain toxins in animals and hormones in feed.
Second, chicken skin is inedible.
Although chicken skin is delicious, it is not good for your health. Generally speaking, chicken skin is rich in fat, cholesterol and pollutants. Especially roast chicken, the cholesterol in chicken skin is oxidized to form cholesterol oxidation products after roasting, which is harmful to human body. If the temperature is not properly controlled, it may also produce carcinogens. Therefore, it is best to remove the chicken skin when eating chicken, and don't use it for cooking.
People's Network-The three parts of the chicken are highly toxic and must not be eaten.
People's Network-The neck, skin and buttocks of chickens are inedible.