The glycogen content in winter and summer of oysters, Ostrea edulis L., of different ages

Abstract

The biochemical composition of adult oysters was determined in January and June, 1974, for five age groups between 18 months and 5 years old. The neutral lipid, phospholipid, free sugar and nitrogen levels were similar in adults of all ages and showed little or no variation between summer and winter. In the summer, the glycogen level was similar in adults of all ages with a mean of 17.1 % of the dry flesh weight. The glycogen level in the winter increased with increasing age of oysters; from 4.6 % of the dry flesh weight in one to two year old adults to 15.2 % of the dry flesh weight in 4–5 year old adults. The latter value is similar to that in the summer (mean 16.4 % of the dry flesh weight).