Effect of salt in the water for transport on survival and on Na+ and K+ body levels of silver catfish, Rhamdia quelen, fingerlings.

摘要

The effect of different salt concentrations (0, 1, 3 or 6 g/litre table salt) in the water used for transport on survival and on Na+ and K+ levels of silver catfish fingerlings was analysed. The fingerlings were kept in water-filled polyethylene bags for 6, 12 or 24 hours. Mortality increased with time of transport and salt concentration, with a significant correlation between these parameters. The water containing salt at 6 g/litre increased body levels of Na+ the most compared with other treatments between 6 and 12 hours. K+ levels of fingerlings transported in water with salt at 1, 3, and 6 g/litre decreased from 6 to 12 hours, compared with fish transported in water without salt. It is suggested that the water used to transport silver catfishfingerlings should not contain salt. Since dissolved oxygen levels decreased to low levels, it is suggested that time of transport should not exceed 12 hours.