Survival and growth of silver catfish larvae exposed to different water pH
J.M. Lopes, L.V.F. Silva, B. Baldisserotto-2001
Aquaculture International, 9(1): 73-80
Abstract:
The objective of this study was to determine the influence of water pH (5.5,
6.0, 7.0, 8.0, and 8.5) on survival and growth of silver catfsh (Rhamdia
quelen) larvae. Larvae were obtained from induced spawning in November and
maintained under controlled conditions of 25 (1) °C using a water re-use
system in continuously aerated 40 L polyethylene tanks (350 larvae/tank).
Larvae were fed until satiation six times a day. At days 0, 7, 14, and 21
and after yolk absorption, 10 larvae from each group were randomly chosen to
evaluate length, weight, and specific growth rate (SGR). Length, weight,
survival, and biomass at the end of 21 days were significantly higher at pH
8.0 and 8.5. As expected, specific growth rate decreased with time. These
results suggest that 8.0–8.5 is the best pH range for survival and growth
of the larvae of this species.