Thumronk Amornsakun, Vuong Hung Vo, Nirattisai Petchsupa, Tan Min Pau, and Anuar bin Hassan

DOI: 10.14456/sjst-psu.2017.16

pp. 137 - 142

Abstract

A study on the effect of water salinity ranging from 0-30 ppt on hatching success of snake head fish, Channa striatus
was conducted in a 15-liter glass aquarium (water volume 10 liters) containing 500 eggs for various levels of water salinity.
Fertilization rates at 0, 5, 10, 11, 12, 13 and 14 ppt were 69.33, 72.67, 71.33, 72.67, 82.00, 73.33 and 10.67%, respectively. The
fertilization rate at 12-13 ppt salinity was significantly (P<0.05) higher than that at 0, 5, 10 and 11 ppt salinity. Hatching rate
at 0, 5, 10, 11, 12, 13 and 14 ppt salinity were 60.00, 60.67, 66.67, 72.00, 77.33, 68.00 and 2.67%, respectively. Hatching rate at
12 ppt salinity was significantly (P<0.05) higher than that at 0, 5, 10, 11 and 13 ppt salinity. For the snake head fish, the water
salinity of 12 ppt was shown to give the highest fertilization and hatching rates. The times of hatching out at water salinity
of 0-14 ppt were between 1,192-1,442 minutes.
After hatching, the survival tolerance of snake head fish larvae in different salinity (0-30 ppt) within 24 hour were then
studied using a 50-liter glass aquarium (water volume 30 liters) containing 50 larvae at each level of salinity. All treatments
were done in triplicate. The survival rate of fish larvae in the 0, 5, 10, 15, 16, 17, 18, 19, 20, 25 and 30 ppt salinity were 100, 100,
100, 100, 0, 0, 0, 0, 0, 0 and 0 %, respectively. However, fish larvae that had survived at 15 ppt died after 8 days of rearing.
The gain rate of total body length, body weight gain rate and survival rate (%) at 10 weeks at water salinity ranging from 0, 5
and 10 ppt were significantly (P<0.05) higher than that at 11, 12, 13 and 14 ppt salinity. However, there were no significance
differences (P>0.05) among 0, 5 and 10 ppt.