Effect of nitrite on larval development of giant river prawn Macrobrachium rosenbergii |
| |
| Authors: | Margarete Mallasen |
| |
| Institution: | a Centro Avançado do Pescado Continental, Instituto de Pesca, Caixa Postal 1052, 15025-970, São José do Rio Preto, SP, Brazil
b São Paulo State University, Aquaculture Center (CAUNESP) and College of Agriculture and Veterinarian Sciences, 14884-900, Jaboticabal, SP, Brazil |
| |
| Abstract: | The effects of ambient nitrite concentrations on larval development of giant river prawn Macrobrachium rosenbergii were evaluated. The trials were conducted in two phases: phase 1, larvae from stages I through VIII and phase 2, larvae from stage VIII until post-larvae. In both phases larvae were kept in water with nitrite (NO2-N) concentrations of 0, 2, 4, 8 and 16 mg/L. Oxygen consumption was analyzed for larvae in stage II at nitrite concentrations of 0, 4, and 8 mg/L. Survival, weight gain, larval stage index and metamorphosis rate decreased linearly with increasing ambient nitrite concentration. However, there was no significant difference between larvae subjected to 0 and 2 mg/L NO2-N. In phase 1, there was total mortality at 16 mg/L NO2-N, while in phase 2 larval development stopped at stage X in this treatment. The oxygen consumption in stage II increased significantly at NO2-N concentration from 0 to 4 mg/L, but there was no difference between 4 and 8 mg/L NO2-N. In conclusion, increasing ambient nitrite up to 16 mg/L NO2-N delays larval development, reduces larval growth rate and causes mortality, whereas no significant effect occurs for levels below 2 mg/L NO2-N. However, the establishment of a general safe level of nitrite to M. rosenbergii hatchery may be difficult due to the great variability in larvae individual sensitivity. |
| |
| Keywords: | Freshwater prawn Larvae Macrobrachium Nitrite |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
