Feeding physiology of the Argentine mussel Mytilus edulis platensis (d’Orbigny, 1846): does it feed faster in suspended culture systems?

Abstract

The feeding behavior of Mytilus edulis platensis, one of the most important aquaculture resources on the East Coast of southern South America, was studied by analyzing clearance rate (CR) and ingestion rate (IR) to test the hypothesis that cultivated mussels can attain higher clearance and ingestion rates than their wild counterparts. A number of morphometric relationships between cultivated and wild mussels were also compared. Gill surface (GS) growth relative to length (L) is isometric in M. e. platensis, with no significant differences between wild and cultivated mussels. At low food concentrations (<15 Chaetoceros gracilis cells ml 1 ), the CR is maximum and similar in both cultivated and wild mussels, decreasing when the concentration of experimental food surpasses a threshold level. This concentration threshold is higher in cultivated mussels than in wild ones. While culture conditions do not affect either GS growth or potential CR, they do affect CR regulation patterns in response to fluctuations in food concentration, allowing the attainment of higher maximum IR.