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The Danube is the second largest river in Europe, having 2857 km long, with a drainage area of almost 801,500 square kilometers. The urbanization, industrialization and agriculture mechanization development have led to the deterioration of Danube water quality due to various contaminants. The aim of this research was to evaluate the main physico-chemical indicators of Danube water, Chilia branch, mainly in Isaccea, Chilia, Izmail and Vilkovo areas, located in the Romania- Ukraine border region. The samples were collected during year 2014, in spring and autumn seasons, and were analyzed in the laboratory for Ecology and Exploitation of Aquatic Resources, at the Department of Aquaculture, Environmental Sciences and Cadastre, Faculty of Food Science and Engineering, "Dunărea de Jos" University of Galati. Sampling and analysis of physical and chemical indicators were performed in accordance with the current standards, available for each indicator separately. The investigated physico-chemical parameters were: pH, dissolved oxygen (DO) and nutrients (N-NH4+, N-NO3-, P-PO43+). The results of this research showed that in the Isaccea, Chilia, Izmail and Vilkovo areas, the physico-chemical indicators are slightly above the admissible values mentioned in surface water quality standard classification (No.161/2006). This is most probably a direct result of human and industrial activities from the previous mentioned areas. [ABSTRACT FROM AUTHOR]

Addition of natural additives (prebiotics, probiotics, phytobiotics) in fish feed is a benefic method because it leads to improved growth performance of fish reared in intensive production systems. Sea buckthorn is one of the most commonly phytobiotics used in aquaculture because of its antioxidant, antimicrobial, immunostimulant, anti-stress, cytoprotective, liver and tissue regeneration properties. Sea buckthorn berries are rich in vitamins (B, C, E and K), flavonoids, carotenoids, tocopherols and many volatile compounds. In this context the aim of this study was to evaluate the effects of dietary vitamin E (500 mg/kg diet) and sea buckthorn on growth performance and survival of the A. stellatus juveniles reared in a recirculating aquaculture system. The experiment took place in the recirculating pilot system of "Dunărea de Jos" University of Galaţi. In order to emphasize the influence of the above mentioned immunostimulants on sevruga fingerlings with different genetic background, four experimental groups from different genitors (V1: ♀2 Danube x ♂1 Aquaculture, V2: ♀1 Danube x ♂1 Danube, V3: ♀1 Danube x ♂2 Aquaculture and V4: ♀2 Danube x ♂2 Danube) have been used. At the end of the experiment no significant differences (p>0.05) were observed in terms of final mean weight, individual growth rate, SGR, FCR, PER, between the sevruga fingerlings obtained from wild genitors, comparing with those obtained from aquaculture genitors. [ABSTRACT FROM AUTHOR]

The aim of this research is to evaluate the influence of sea buckthorn (Hippophae rhamnoides) and vitamin E on growth performance indicators and oxidative stress at Nile tilapia juvenile, reared in a recirculating aquaculture system. The experiment was conducted six weeks, in triplicate. The experimental variants were: V1-control, V2-1% sea buckthorn/kg feed, V3-500mg vitamin E/kg feed and V4-1% sea buckthorn supplemented with 500 mg vitamin E/kg feed. During the experiment was performed an intermediary biometric measurement. Oxidative stress analysis consisted in determination of lipid peroxidation (MDA-malondialdehide) and total antioxidant capacity (TAC) from liver, muscle tissue and gut. Results showed a good evolution of GR, FCR and SGR, during the experiment, in V4-in which feed was supplemented with sea buckthorn and vitamin E. Based on the results obtained in variant V4, in liver and muscle tissue, the oxidative stress was reduced. Regarding MDA and TAC, between experimental variants, were registered significant differences (p<0.05) at the level of muscle tissue and gut. In conclusion, the research shows that sea buckthorn (1%/kg feed) in combination with Vitamin E (500mg/kg feed) has a synergistic effect on growth performance indicators and oxidative stress, at Oreochromis niloticus juvenile. [ABSTRACT FROM AUTHOR]

The aim of this work presents the results of an experiment that was conducted over a period of 30 days (24.05.2013-22.06.2013), where we used specimens of A. stellatus (Starry) aged 13 months and 22 days. We have used two tubs: in the first tub were 40 species with a total biomass of 3916 g and in the second tub were 39 species with a total biomass of 4012 g. The fish from the two tubs were fed with fodder "Alterna Storione", the difference between the two tubs is: in the first tub we have to incorporated the vitamins C and E, and in the second tub we used the feed as it self. At the end of the experiment, in the first tub (C + E) we obtained a weight gain of 1199 g, and in the second tub we obtained weight gain of 1153 g. In the hematological profile we have obtained the following results: in the first tub (C + E) the hemoglobin 8.58±0.94 g/dl the glucose 69.46±7.12 ml glucose / 100ml blood, the proteins 3.83±0.28 g proteins/100 ml serum, hematocrit 26.46±3.67, the leukocyte 1.65±0.070 and the erythrocytes ranged from 0,77. 106 cells / μl blood and 0,875. 106 cells / μl blood; in the second bath(control): the hemoglobin 9.23±1.66 g/dl, the glucose 62.06±4.75 ml glucose/100ml blood, the proteins 3.7±0.33 g proteins/100 ml serum, the hematocrit 30.48±5.71, the leukocyte 1.69±0.085 and the erythrocytes ranged between 0,67 . 106 cells / μl blood and 0.745 . 106 cells / μl blood. In summary, we obtained different values referring to the gain, the increase of the specimens used in the both baths and their hematological profile was affected by the feed method used differently in the two baths. [ABSTRACT FROM AUTHOR]

The main objective of the present research is to evaluate the biochemical composition of A. stellatus meat, after the administration of the phytobiotics in feed. One year and four months old A. stellatus fish were used, with an initial average weight of 121.21 ± 68 g / fish. The experimental trial lasted days and was hold at the pilot aquaculture recirculating system. The phytobiotics used were incorporated in feed with gelatin in a concentration of 2% / kg feed and were represented by thyme (Thymus vulgaris) that the seabuckthorn (Hippophaerhamnoides). Two experimental variants were made: V1 - sea buckthorn and V2 - thyme. The fish were fed with Alterna Storione feed, with 48% crude protein and 16% fat. During the experiment, the water physico-chemical parameters were in the normal range for an optimal growth of stellate sturgeon. At the end of the experiment significant differences (p<0.05) were observed between the two experimental variations in terms of dry matter, protein, fat and moisture content. Not significant differences (p>0.05) were recorded concerning the percentage of ash. The highest value of moisture (83.44%) was recorded in V2 (thyme), the lowest fat content (0.29%) was recorded in V1 (seabuckthorn). In conclusion, the two types of phytobiotics (thyme, seabuckthorn), administered in a concentration of 2% / kg feed, significantly influenced the biochemical composition of A. stellatus meat. [ABSTRACT FROM AUTHOR]

The aim of present study was to evaluate the hematological parameters and the absolute number of leukocytes of European catfish (Silurus glanis) maintained in different technological conditions induced by applied stocking densities. The experiment was conducted over a period of 32 days. A number of 450 European catfish, with an average weight of 158.9±0.26 g, were distributed in four rearing units, in order to create different stocking densities as follows: V1-14.28 kg/m3, V2-28.59 kg/m3, V3-42.97 kg/m3 and V4-57.06 kg/m3. The following hematological parameters were determined: RBC, Ht, Hb, MCV, MCH and MCHC. A decrease of RBC and higher values of MCH and MCHC were observed at V4, while at V1 an increase in RBC and lower MCV, MCH values can be seen. Regarding the absolute number of leukocytes, no significant statistical differences were registered between the applied stocking densities (p>0.05). However, there was a slight increase of leukocyte number with increasing stocking density (240.01 x103cel./mm3 at V4, respectively 189.64 x103cel./mm3 at V1). It can be concluded from hematological parameters analysis that a stocking density of 60 kg/m3 seems to be out of the optimal range for catfish growth, in current growth conditions. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]