Evaluation of the development of striped catfish (Pangasianodon hypophthalmus) from fingerling to sub-adult stage of two broodstock sources under saline water condition

Abstract

This study aimed to investigate the development of striped catfish from fingerling to sub-adult from two sources of broodstock under saline water conditions. Experimental fish are of two sources of broodstock: one from the selected group (saline tolerate group) that was selected (10 ppt) and conditioned under saline stress (5ppt) and the other source (control group) come from normal hatcheries of striped catfish in freshwater. The distinguishing between selected group (red color) and freshwater group (green color) by using the visible implant elastomer (VIE). VIE-stripped catfish from two groups were reared in the same composite tanks (10 m3) with a stocking density of 260 fish/tanks with four replicates (with a total of 4 tanks for 2 treatments). The fish were acclimated with the saline condition until getting the targeted level of 10 ppt. Striped catfish were fed with commercial pelleted feed with the level of protein ranging from 28 to 35% according to their size. The feed was added with vitamin C and digestive enzymes. During the culture period, there was slight fluctuation within a daytime of parameters such as dissolved oxygen, pH, and temperature, but still in suitable ranges. After 69 days of the culture, with salinity stress, the number of cumulative fish that died from the freshwater group (53) was significantly higher than that of the selected group (15) (p<0.05). The growth performance of offspring from the selected group was better than that of the freshwater group, especially in daily weight gain with significantly different (p<0.05). These results suggested that the offspring from the selected group can better adapt to saline stress than that of the freshwater group.