1. The collarbone of a duck is the prominent bone under the neck. Commonly known as duck rack. The main food is the sternocleidomus muscle attached to the bone and the cartilage at the joint. Duck clavicle is at the joint of duck neck and body, so it is also the part where lymphatic organs are concentrated.

2. Thymus is the primary lymphoid organ of animals. As the immune system of animals, lymphoid organs contain many germs and viruses, so they are not edible. However, the thymus has been removed from the neck of the treated chickens and ducks, and generally only a few small lymph nodes are assembled, so eating them will generally not cause harm to human health.