Haemolymph parameters in the shore crab (Carcinus maenas) (copy)

The primary objective of this pilot study is to establish whether immune function (phagocytosis) in shore crabs (Carcinus maenas) can be effectively measured using a new flow cytometry method that has been developed in our laboratory using blue mussels. Secondary objectives will investigate the influence of reduced seawater salinity on the blood parameters such a cell count and immune function. It is expected that there will be minimal stress for the crabs.The procedure is non-destructive and involves sampling blood from the base of a walking limb. Exposure of the crabs to reduced salinity will be at levels they could encounter in the field. Crabs will be collected by hand from the field and released at the end of the procedures. The overall goal of the study is to establish an ecologically relevant measurement endpoint that may be used to determine the effects of climate change on coastal animals. A total of 20 male adult crabs will be used for this pilot study. At present there are no available replacement techniques that could be used. The number of animals has been reduced to the minimum required to ensure statistical strength in the analysis, based on previous research with this species. The methods used are non-destructive and crabs will be returned to the field following the procedures.