不是.

Beef Sweetbread

Sweetbread is the thymus gland of animals. It is a light meat that is firmer in texture than brains. The sweetbreads of veal are considered the best. Beef sweetbreads are rather fatty and coarse, but if well prepared, they will taste almost the same as veal.  No on bothers with pork sweetbreads. Beef sweetbread is found along the top of the neck vertebrae on the Front Quarter of the beef.  After the age of 1 to 1 1/2 years, the beef Thymus Gland usually shrinks. After the age of 2, it is usually gone completely from the beef.