Asian-Pacific Aquaculture 2019

June 19 - 21, 2019

Chennai Tamil Nadu - India

EFFECT OF MULTIPLE STRESSORS AND DIETARY NUTRACEUTICAL ON HEPATIC ANTIOXIDANT STATUS IN Labeo rohita (HAMILTON, 1822) FINGERLING

Shamna N.*, Sahu N.P., and Sardar P.
Fish Nutrition, Biochemistry and Physiology Division, ICAR-Central Institute of Fisheries Education, Mumbai-61, India
 
*shamna@cife.edu.in
 

Four month feeding trial was conducted to evaluate the effect of a nutraceutical conglomerate on Labeo rohita fingerlings (Hamilton, 1822) exposed to crowding and feed restriction. One thousand and eighty (1080) acclimated rohu fingerlings with an average size of 8.5 ± 0.5 g were randomly distributed in 6 distinct experimental groups in triplicate, where first three groups were exposed to high stocking density (HSD; 20 nos / 75 L water) with restricted feeding (RF) and second three groups were exposed to normal stocking density (NSD; 10 nos /75L water) with satiation feeding (SF). Nutraceuticals were fed to both stress exposed and unexposed groups at 0, 0.1 or 0.5% levels. Hence, the six experimental groups were designated as THR0 (HSD, RF, 0% nutraceutical), THR1 (HSD, RF, 0.1% nutraceutical), THR5 (HSD, RF, 0.5% nutraceutical), TNS0 (NSD, SF, 0% nutraceutical), TNS1 (NSD, SF, 0.1% nutraceutical) and TNS5 (NSD, SF, 0.5% nutraceutical). Monthly sampling was done during four months experimental period. The results indicated that the superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and Glutathione-s-transferase (GST) enzyme activities and respective genes of first three (SOD-1, CAT-1 and GPx-1) expression were significantly higher (P<0.05), whereas, serum total antioxidant status (TAS) lower (P<0.05) in fish of HSD with RF at the end of every month of the experiment. Stress exposed fish although exhibited significantly lower (P<0.05) reduced glutathione (GSH) levels at the end of second and third month of the experiment, it was significantly higher at the end of first and fourth month of the experiment. However, feeding nutraceuticals could not recover some but all the parameters up to the level of stress unexposed fish. Among the stress unexposed groups, feeding of 0.5% nutraceutical significantly increased SOD and CAT activities at the end of second and third month and third and fourth month, respectively. GPx gene expression was reduced at the end of third month due to feeding of both 0.1 and 0.5% nutraceutical, whereas GPx enzyme activity was reduced at the end of fourth moth due to feeing of 0.1% nutraceutical. Feeding both 0.1% and 0.5% nutraceutical increased the GST activity in fish at the end of third and fourth month. GSH level and TAS value were reduced at the end of third month due to feeding of both 0.1 and 0.5% nutraceutical.Among stress exposed groups, feeding both 0.1% and 0.5% nutraceutical reduced the GPx gene expression in fish at the end of third and fourth month, whereas GPx enzymatic activity was reduced at the end of fourth month due to feeding of 0.1% nutraceutical.Feeding both 0.1% and 0.5% nutraceutical reduced the SOD gene expression in fish at the end of third month, whereas SOD enzymatic activity was reduced at the end of fourth month.Feeding both 0.1% and 0.5% nutraceutical reduced the CAT gene expression in fish at the end of second month, whereas CAT enzymatic activity was reduced at the end of third and fourth month. GST activity and GSH level were increased in fish at the end of third and second month, respectively due to feeding of both 0.1 and 0.5% nutraceuticals. Serum TAS was significantly increased in stress exposed fish due to feeding of both 0.1 and 0.5% nutraceutical at the end of every month of the experiment. Two-way ANOVA revealed that 0.1% dietary nutraceutical could better improve the antioxidant status in stress exposed fish