Effects of water pH on physiological parameters and color changes of Asian Bumblebee Catfish (Pseudomystus siamensis Regan, 1913)

Abstract

Effects of water pH on blood physiological parameters and color change of Asian bumblebee catfish (Pseudomystus siamensis) (4 – 6 g/fish) were carried out in laboratory condition. The experiment was set up in 8 weeks at different pH water levels (pH = 3, 4, 5, 6, 7, 8, 9, 10, 11). The results have shown that the cumulative mortality ratio of Asian bumblebee catfish at the end of 24 h challenge was 100% at pH = 11, 70.83% at pH = 10, and 62.5% at pH = 3. No mortality of fish was observed at pH = 4, 5, 6, 7, 8, 9 after 24 h of the challenge. The lowest and highest pH threshold that killed 50% of fish after 24 h of the challenge were 3.04 and 9.95, respectively. After 24 h of the challenge, total number of red and white blood cells of fish increased at pH = 3, 9, 10, and get the highest level at pH = 3 (1.87 × 106 cells/mm3 and 1.59 × 105 cells/mm3, respectively. At the end of the challenge, highest number of red and white blood cells were observed at pH = 8 (2 ± 0.23 × 106 cells/mm3 and 1.27 ± 0.26 × 105 cells/mm3, respectively). Fish were in bright and beautiful color when cultured in high pH water levels.