Research regarding age influence on slaughtering value at European catfish (Silurus glanis).

From economic point of view, a very important role in optimization of production in aquaculture is represented by slaughtering age of the population destined to commercialization. The current paper aims to establish the existent correlation between slaughtering age and participation of cutting regions in composition of total corporal mass for breed Silurus glanis. Experiences were carried out on three batches of European catfish with different ages (2 nd summer, 3 rd summer and 4 th summer), reared in soil basins in extensive system. For feeding, the studied population utilised the natural trophic resources in basins, being composed mainly from fishes which belongs to Cyprinidae family. Environmental growing conditions in rearing system were the ones characteristic for NE area of Romania. Mean weight at slaughtering for first batch (L1) was 890.06 g, for second batch (L2) was 1345.89 g, and 2109.83 g for the third batch (L3). Was studied warm yield in carcass, torso and skinless filet, and also the rate of head, viscera, gills, fins, vertebral column, skin and barbels in composition of total corporal mass. From commercial point of view present interest the muscular tissue which has the highest rate in comparison with other cutting regions, recording values between 41.05 and 50.15%, from total corporal mass. At opposite spleen is situated, these one having the lowest values related to corporal mass, for all three batches.