Assessment of haemolymph parameters of some freshwater snails and mussels collected from a lentic habitat of Bangladesh

The present study was conducted to determine certain haemolymph parameters of natural populations of two freshwater snails Pila globosa and Filopaludina bengalensis, and four unionid mussels Lamellidens jenkinsianus, L. phenchooganjensis, L. marginalis, and L. corrianus collected from Darikanthal Beel, Trishal, Mymensingh. Twenty apparently healthy live snails and mussels from each population collected at the same date were selected for haemolymph analysis. A non-lethal sampling technique was adopted for collecting haemolymph from the snails and mussels. The haemolymph parameters Na+, K+, Cl−, glucose concentrations and pH levels were determined for each specimen. Significant differences (P < 0.05) were found in almost all the haemolymph parameters among the sampled snail and mussel populations. This study provided reference ranges for some vital haemolymph parameters of the two freshwater snail species and four unionid mussel species. These ranges are measurable non-lethally and could be applied to biological monitoring of environmental stressors using the molluscs as indicator species.