Tropicultura (Jan 2016)
Impact of Salinity on the Incubation Rate and the Performance during the Nursery Phase of Square Head Climbing Perch (Anabas testudineus Bloch, 1792)
Abstract
Square head climbing perch (Anabas testudineus Bloch, 1792) is a high quality fish without small bones. It grows in a wide range of temperatures (10-42 oC), pH (3.5-9.5) and salinity (up to 16%). As regards climate change, this species may become important for aquaculture in the Tam Giang-Cau Hai lagoon near Hue city. To optimise the quality of fingerlings, we analyzed the effect of salinity levels on hatching and nursing in three subsequent experiments. Fertilization, hatching, survival and growth rates for 30 days were determined at salinity levels 0%, 5%, 7%, 13% and 15%. Water temperature and pH varied between 22-29.5 oC and 7.3-7.8, respectively. Between 0-5%, fertilization ratio was 77% to 83% and highest at 5%, but this dropped to 0% when salinity increased; hatching ratio was larger than 90%, but decreased to 0% at 13-15%. Between 0-11%, hatching time of fertilized eggs was not affected by salinity levels. The ratio of deformation gradually increased above 5%. After hatching at either 0 or 5%, survival ratios for square head climbing perch were above 13% up to 5%, but dropped to 0% at 9%. The growth after 30 days of nursing was higher at 5 and 7% compared with that of 0 and 3%.
