What month is the fattest and most delicious oyster?

December to April of the following year.

Generally, oysters are stocked in May, and they are fished about six months after being cultured. After entering winter, the cold weather makes the energy consumption of oysters less, and the meat quality will be fatter, until the Qingming Festival next year, that is, at the beginning of April. Oyster (scientific name: Ostreidae), also known as oyster, oyster yellow and oyster seed, is a kind of shellfish species with short food chain, fast growth, high yield and wide distribution. There are many external forms of oysters, but they often have the shape characteristics of unequal shells, toothless hinge and sometimes nodular small teeth. Oysters have a large left shell, a flat side and symmetrical left and right sides. The outer shell is located inside the shell, which is thin and transparent, and its external shape often changes greatly with different living environments. It is difficult to distinguish many oysters simply by the external shape of the shell.