Alina Antache


THE INFLUENCE OF SOME PHYTOBIOTICS ON OXIDATIVE STRESS AT OREOCHROMIS NILOTICUS GROWN IN AN INTENSIVE RECIRCULATING AQUACULTURE SYSTEM

Alina Antache, V. Cristea, Iulia Grecu, Lorena Dediu, Angela Docan, Mirela (Creţu) Mocanu, Săndiţa (Ion) Plăcintă, M.T. Coadă

Abstract
The purpose of this paper was to evaluated the influence of several phytobiotics on oxidative stress, at Oreochromis niloticus species, reared in an intensive recirculating aquaculture system. The phytobiotics from this experiment were administered in feed, in a concentration of 1%/kg feed, and consist in: thyme (Thymus vulgaris) in V2, fenugreek (Trigonela foenum graecum) in V3, neem (Azadirachta indica) in V4 and V1 represented the control variant. A total number of 180 fish, with an average initial weight of 125.41 ± 34.33 g/fish, were randomized distributed into four rearing units. The oxidative stress was determined by analysing the lipid peroxidation indice (malondialdehyde - MDA), total antioxidant capacity (TAC) and reduced glutathione (GSH). The analyses were measured spectrophotometrically in the research laboratory of Aquaculture, Environmental Science and Cadastre Department, University "Dunarea de Jos" Galati. The MDA concentration recorded the highest values at V2 - thyme (9.45 nmol/ml tissue; 7.75 nmol/ml gut). The same variant (V2) also recorded the highest value of GSH concentration (1.075 µmol/dl). Regarding TAC concentration, the lowest values was recorded at V3 - fenugreek and V4 - neem (plasma, tissue, liver, gut). In conclusion, the results of this study demonstrate that thyme is an important additives, for conferring wellfare, in commercial diets of Oreochromis niloticus.

Key words: phytobiotics, oxidative stress, Oreochromis niloticus, intensive recirculating aquaculture system