Using certain gestures (non verbal communication), we can put animals in a trance. The principle behind is valid for human persons, too. Normally, to hypnotize animals, we have to catch and block them, and after we use passes, or gaze, to hold their attention in a certain direction.
For instance, to hypnotize a chicken, we have to force the hen's head flat to the ground, and to draw a line directly out from its beak. The animal will stay staring at this line; to hypnotize a guinea pig we have to roll the animal over and over some time on the table, and then lay it on its back. And the guinea pig will remain quiescent.