Comparison of the seasonal variation of the biochemical composition in two species of freshwater crayfish from southern Brazil

The aim of this study was to compare seasonal variations in the metabolism of two crayfish species with different habitats, Parastacus defossus that lives in subterranean galleries with low oxygen concentrations and Parastacus brasiliensis that lives in oxygenated environments. The metabolism of the species was compared, mainly evaluating the mobilization of the reserves for the reproductive period, and the metabolic response during the seasonal cycle. Seasonal sampling was conducted from spring 2006 to winter 2007. P. brasiliensis was collected at Mariana Pimentel, and P. defossus at Lami, Porto Alegre, Rio Grande do Sul. Hemolymph, hepatopancreas, muscle, gills, and gonads were removed for determination of glucose, free glucose, glycogen, lactate, total protein, total lipids, total cholesterol, and arginine phosphate. The hepatopancreatic and gonadosomatic indexes were determined. The results showed different seasonal responses between the species for all metabolic parameters, wit...