SEASONAL-VARIATION OF THE CARBOHYDRATE AND LIPID-METABOLISM IN A LANDPULMONATE GASTROPOD, MEGALOBULIMUS-OBLONGUS

Seasonal variations of carbohydrate and lipid metabolism. in Megalobul imus oblongus were investigated. Haemolymph glucose levels were higher in summer than in other seasons. The glycogen content of the hepatopa ncreas, muscle and mantle was constant throughout the year, except in winter when lower values were found. Hepatopancreas total lipid increa sed in spring, whereas gonad total lipid increased in winter and sprin g. Glycogen metabolism seems to constitute the source of energy substr ate during winter while lipid metabolism may be related to the annual reproductive cycle.