An evaluation of different methods for transportation of the freshwater mussel Lamellidens corrianus (Lea 1834)

The freshwater mussel Lamellidens corrianus (Lea 1834) is widely distributed in ponds and large bodies of perennial waters in the Indian subcontinent. It is one of the important species for producing freshwater pearls in India. As the freshwater pearl aquaculture activity may expand on wide scale in future, it may require collecting L. corrianus from the distant places and transport to pearl producing centres. Hence, in order to develop suitable method for transportation of L. corrianus to obtain high survival with minimum physiological stress, the present study was conducted. L. corrianus were transported by two different methods i.e. in air (in wet gunny bags) and in water (in plastic polyethylene bags containing water) to find out the best method for transportation. Glucose was chosen as the stress factor as the heightened circulating glucose levels may reflect the bivalve’s ability to respond to weather extremes, handling stress or any recent environmental stress perceived to require extra energy. Experiments were conducted both under field as well as laboratory conditions, during the start of winter season, where regional temperature falls to 4–5°C below the average. Under the field experiment, L. corrianus (total length = 8.26 ± 0.34 cm; wet weight = 52.62 ± 3.18 g) were transported by road from Khopoli (Dist. Raigad, Maharashtra State) to Ratnagiri (Dist. Ratnagiri, Maharashtra State) for 12 h in air and water (reservoir water temperature = 26.4°C). Under laboratory conditions, simulating air transportation was done in wet gunny bags (42.5 cm × 62.5 cm), each bag containing 50 mussels (total length = 8.34 ± 0.46 cm; wet weight = 53.2 ± 3.24 g). Simulating water transportation was carried out using plastic polyethylene bags (45 cm × 60 cm), with 50 mussels in five litres of water (water temperature = 26.5°C). At periodical intervals, glucose concentrations from mantle, gill and posterior adductor muscle were estimated. Under both field and laboratory conditions, glucose levels were significantly higher in mantle, gill and posterior adductor muscle tissue of L. corrianus transported in air when compared to that of water-transported mussels. Results showed that air transportation was comparatively more stressful than water transportation. However, cent per cent survival was obtained in the both methods just after transportation and after 7 days of transportation. Considering the absence of mortality in both methods, it can be concluded that the choice of the mussel transportation method is more economical dependent than biological dependent.