ผลของชีวภัณฑ์กรด 5-อะมิโนลีวูลินิกต่อการเจริญเติบโต และการตอบสนองของภูมิคุ้มกันในปลาสวายปรับปรุงสายพันธุ์ (Pangasianodon gigas x Pangasianodon hypophthalmus)

Abstract

The present study the effects of bioproduct ALA from R. palustris JP225 on growth performance and immune responses in hybrid striped catfish (Pangasianodon gigas x P. hypophthalmus). Hybrid striped catfish with an initial weight of 7.71 - 7.78 g were fed with commercial diet supplemented with ALA at concentrations of 0 (control), 2.5, 5.0, 7.5 and 10.0 mg/kg. After 4 weeks of feeding, the fish received diet containing 2.5 mg/kg ALA exhibited significantly highest final weight, weight gain and specific growth rate with the best feed conversion ratio in comparison with fish fed with other diets including control (p<0.05). Furthermore, fish fed with 2.5 mg/kg ALA showed significantly higher red and white blood cells, haematocrit, serum protein, total haemogolbin, phagocytosis, phagocytic index and average bead per cell than those of the control group (p<0.05). After 8 weeks of feeding, no significantly difference was observed among treatments for growth performance (p>0.05). Moreover, haemato- immunological study revealed significantly decreased total haemoglobin, haematocrit and serum protein but significantly increased Nitrobluetetrazolium reduction and phagocytic index observed in fish fed the diet supplemented with 10 mg/kg ALA compared to the control group (p<0.05). Histopathological alteration were studied in liver, kidney, stomach and intestines collected from the fish fed diets supplemented with ALA. The result showed that ALA at concentrations of 0 (control), 2.5, 5.0, 7.5 and 10.0 mg/kg had no effect on fish tissue. These findings indicated that supplementation of bioproduct ALA from R. palustris JP225 at concentration of 2.5 mg/kg diet for 4 weeks enhanced growth performance and immunity of hybrid striped catfish.