Dietary Carotenoid Supplementation Improves Fillet Appearance, Antioxidant Status and Immuneresponses in Striped Catfish (Pangasianodon hypophthalmus) Neverthless the Growth Performance

Özet

A feeding trial of 45 days was conducted for delineating the effect of carotenoids on the fillet appearance, antioxidantstatus and nonspecific immune responses of Pangasianodonhypophthalmusfingerlings. Two hundred and fifty-two fingerlingswere randomly distributed into seven different experimental groups in triplicates. Seven isonitrogenous and isolipidic dietswere prepared with two levels (150 and 300 mgkg-1) of astaxanthin (T2 & T3), beta-carotene (T4 & T5), canthaxanthin (T6 &T7) and a control diet (T1) without any carotenoids. The experimental fish were fed daily at the rate of 3% body weight in twoinstalments. At the end of the experiment, the fish were sampled to evaluate the colour and texture parameters, of fillets alongwith antioxidant and nonspecific immune status of fish. The fillet colour exhibited significantly higher(P<0.05) intensity ofredness in the groups fed astaxanthin and a higher yellowish colouration in the beta-carotene fed groups. Significant (P<0.05)reduction in the activities of antioxidant enzymes and a significantly (P<0.05) higher PUFA/SFA ratio was also observed inastaxanthin fedgroups. The total erythrocyte count, haemoglobin, respiratory burst, lysozyme activities were also enhanced inboth astaxanthin fed groups (T2 & T3). The effect of carotenoids in modulating the texture of pangasiusfillets was diminutiveand further, there was little influence of carotenoids on growth. Thus, from this study, it can be concluded that astaxanthinsupplementation can improve fillet appearance, antioxidant status and enhance the nonspecific immune response.