Dietary supplementation of vitamin C: an effective measure for protection against UV-B irradiation using fish as a model organism

摘要

The development of UV-B protective mechanisms in aquacultural species is essential for the sustainable production of healthy aqua crop. Freshwater carp Catla catla larvae (13.5 +/- 1.12 mg) were fed with a diet containing 0.5 vitamin C (D1) and a control diet (D2) for 40 days. Each group was exposed to two doses of UV-B irradiation: 360 (5 min, D1(5) (min) and D2(5 min)) and 720 mJ cm(-2) (10 min, D1(10) (min) and D2(10) (min)) for 15 days. Significantly (p 0.05) higher survival and average weight were recorded in D1 compared to D2 exposed to the same dose. Also, significantly (p 0.001) higher nitric oxide synthase and lower thiobarbituric acid reactive substances and heat shock protein 70 levels were recorded in D1(5) (min) compared to the other groups. A direct relationship was found between the dose of UV-B and DNA fragmentation in muscles. DNA damage indices such as tail DNA, tail extent moment and olive tail moment were significantly (p 0.01) lower in D1(5) (min). Thus, supplementation of vitamin C in the diet provides UV-B protection to larvae.