Through these, we know that sows need breeding: sows have many characteristics in estrus and will be restless; Watergate is red and swollen with mucus flowing out; The feed intake of sows is reduced or not directly fed; The sow's eyes are dull and dull. When the wild boar approaches, it will show its ears erect and its body tremble. When it hits the sow's back, it will stand still or even sit back. Vaginal mucosa is red, swollen and shiny, and gradually turns dark red.