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bioRxiv · 10.1101/2023.02.15.528625

Evaluation of physiological responses in selected tissues of a freshwater fish (Cyprinus carpio var koi) maintained in hard waters: A report on glucose, oxidative stress and antioxidant biomarkers

Dasgupta, P.
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Abstract

Fishes endemic to freshwater habitat are strongly influenced by water hardness with physiological consequences. The present study aimed to understand the effects of four-fold sequential increase from soft to hard waters, on selected tissues of Koi carp, a popular ornamental freshwater fish. Secondary stress markers - Glucose, Oxidative stress (Malondialdehyde - Lipid Peroxidation damage) and Antioxidants (Catalase, Glutathione-S-Transferase and Glutathione) were quantified in gills and white muscle after 14 days of exposure to hardness of 75 (Soft - TS), 150 (Moderate - TM), 225 (Hard - TH) to 300 (Very Hard - TV) mg CaCO3/L. Both the examined tissues were distinctly affected by soft and moderate waters. Glucose in gills (p < 0.05) was proportional to the rise in hardness concentration. Soft, moderate and very hard waters (75, 150 and 300 mg CaCO3/L) affected gills and muscle due to elevated MDA concentrations (p < 0.05). CAT and GST provided antioxidative protection to the tissues. The study results showed tissue-specific differential responses and more importantly, concentrations below 225 mg CaCO3/L elicited strong oxidative impairment in both gill and muscle.

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Dasgupta, P.. 2023-02-15. Evaluation of physiological responses in selected tissues of a freshwater fish (Cyprinus carpio var koi) maintained in hard waters: A report on glucose, oxidative stress and antioxidant biomarkers. https://doi.org/10.1101/2023.02.15.528625

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