Effect of water temperature and diet on growth and mortality of Neptunea arthritica juveniles

The growth and mortality of Neptunea arthritica juveniles hatched from different egg masses (controlled conditions and field) reared at 10 and 15 °C, and provided with sardine (D1) and polychaete (D2) as foods were evaluated. Results showed that diet type and water temperature significantly affect the growth and mortality. Interaction between these factors reflected robust relationship among them, but restricted exclusively to growth. Through the study period, juveniles treated at 10 °C showed maximum increments of 2.5 mm (shell length), 2.3 mm (shell width) and 0.25 g (body weight) from their initial size. While maximum values of those treated at 15 °C for the above-mentioned parameters were 7.6 mm, 5.5 mm and 1 g respectively. In both cases, these increments were recorded for individuals fed with sardine. Mortality was significantly affected by diets and water temperature, which significantly increased under D2 10 °C (20–67%), 15 °C (70–87%)] or 15 °C D1 (30–83%), D2 (70–87%)]. According to the results, juveniles of N. arthritica could be maintained under controlled conditions, which allows growth improvement. Mortality appears to be the limiting factor, but this could be improved by the implementation of efficient culture method, basically oriented to increase the water quality.