Survival rate, sex ratio and zootechnical performances were evaluated on 168 kg of Anguilla anguilla elvers (0.45 gj weaned into three groups (Al, A2, A3) at initial densities of 800, 1600 and 3200g m-j, respectively. In order not to modify the sex ratio, animals weaned at the different densities were maintained separately during the trials, and no size grading was performed at the fattening phase.Final mean weight achieved by females belonging to the different groups showed no statistically significant differences; weight of males was higher (P < 0.05) in A1 than in A3 where a higher percentage of males was observed. Sex ratio of eels was different among the groups, with a higher percentage of males in A3 (96%) than in A2 (78%) or in Al (69%). This finding testifies to a sex differentiation strongly affected by pre-fattening stocking density of elvers. Final load showed an increase in males corresponding to a significantly reduced biomass between A1 and A2 (10.97 and 10.24kg m-3) and A3 (8.44kg m-3). Final survival rate ranged from 87% ( A l j to 90% (A3). As to food conversion, a better rate was found in A1 (1.9:l) compared to A2 (2.1:l) and A3 (2.3:lj eels.

This study aimed to evaluate the influence of different volumes of supplemented carbon dioxide. which is a potential donator of carbon atom, on the fatty acid profile of four microalgae strains (Nannochloropsis sp., Nannochloropsis oculata (Droop) Hibberd. Nannochloris atomus Butcher and Isochrysis sp.) currently used to enrich rotifers fed to marine fish larvae during two different phases of growth (logarithmic and stationary). Half of the microalgae were cultured at a low CO2 concentration (0.5 L/min). corresponding to 1 % the air volume (0.038 L/min per L of culture) and the other half of microalgae were cultured at a high concentration of CO2 (1.1 L/min), corresponding to 2% the air volume (0.086 L/min per L of culture). The resulting fatty acid profile was species‐specific and Nannochloris atomus appeared less suitable for inarine organism feeding because of its high percentage of alpha‐linolenic acid which represents the only n‐3 PUFA of this alga (28.7%). On the contrary, Isochrysis sp. showed the largest proportions of n‐3 PUFA also when maintained in the stationary phase (36.46%). Algae cultures contained higher percentages of n‐3 PUFA during the logarithmic phase than in the stationary phase when the proportions of short‐chain fatty acids increased. High levels of concentrated CO2 generally increased the content of long chain fatty acids from 17 carbon atoms onwards. The percentages of total n‐3 and n‐6 were higher than those recorded at low CO2 concentration. Similarly, the n‐3/n‐6 ratio was higher at the maximum CO2 concentration (logarithmic phase). During stationary phase the difference between the two groups was less apparent than that observed in the logarithmic one. The high CO2 addition exerted a significant and more favorable influence than the low supplementation on the C18:1, C20:0, C20:4n‐6, and C22:6n‐3 concentrations in both phases, in all four microalgae strains studied.

Seabass (SBS) and seabream (SBM) juveniles were reared with the goal of obtaining three different final densities (SINT ¼ 40 kg m )3 ; INT ¼ 20 kg m )3 ; SEM ¼ 0.2 kg m )3 ) to ascertain the effects thereof on the welfare of the fish. Significant blood metabolites and hepatic glycogen were determined every 3 months and at harvest. Trials lasted 18 months in seabass and 17 months in seabream. At the end of experiment the main biometric productive parameters and quality of body composition were also recorded. Regarding intensively reared seabass (SINT-SBS, INT-SBS), the plasma triglycerids, total cholesterol and transaminases (AST, ALT) were always significantly higher than in semi-intensively maintained fish (SEM-SBS). At the final sampling in the SINT-SBS batch, the total protein and glucose were also markedly increased. Conversely, at harvest the liver glycogen content decreased in SINT-SBS (34 ± 8 mg g )1 liver) with respect to INT-SBS (57 ± 12 mg g )1 liver) and SEM-SBS (63 ± 11 mg g )1 liver). No differences among groups were observed for creatine kinase (CK) and lactate dehydrogenase (LDH). With regard to seabream, SINT-SBM and INT-SBM constantly showed plasma triglycerids and total cholesterol as being significantly higher when compared to SEM-SBM. In the final two blood samplings, SINT-SBM exhibited the most elevated values for LDH. At harvest, AST, ALT, total protein and glucose markedly increased in SINT-SBM, whereas liver glycogen content was reduced (22.5 ± 9 mg g )1 liver), more than in INT-SBM (70 ± 16 mg g )1 liver) and SEM-SBM (75 ± 20 mg g )1 liver). In both seabass and seabream, body composition was very similar in the different stocking densities, except for total cholesterol. Total n-3 polyunsaturated fatty acid (PUFA) in seabream was significantly different from fish of the semi-intensive groups; however, nutritional values and fatty acid profiles were equally good. The intermediate final density of seabass and seabream at 20 kg m )3 seemed to give the best results in terms of their well being when compared to fish reared at 40 kg m )3 . The absence of differences in blood metabolites and hepatic glycogen levels between the intensive batch and the semi-intensive groups until harvest was a reference to the positive status of the fish. A density of 20 kg m )3 can be considered acceptable for farm strategy planning for raising healthy on-growing seabass and seabream juveniles.

The aim of this study was to evaluate the effects of different genotypes and of feeding on meat chemical composition, including fatty acid profile, of chickens reared under organic conditions. Twomeat–typefast-growing(FG) andmedium-growing(MG), andoneegg-typeslow-growing(SG) wo meat–type fast-growing (FG) and medium-growing (MG), and one egg-type slow-growing (SG) strains were assigned to 2 different diets differing for the protein source: soybean (SB) and faba bean (FB) in partial substitution of soybean. Genotypemarkedlyaffectedthemeatchemical composition. Genotype markedly affected the meat chemical composition. SG breast and thigh meat showed lower content of lipids (P<0.01) than FG. Thehighestproportions he highest proportions of polyunsaturated fatty acids (PUFA) n-6 and n-3 and the lowest proportion of monounsaturated (MUFA) (P<0.01), as well as the lowest ratio of PUFA n6/n3 (P<0.01) were found in SG breast and thigh meat. MG showed always intermediate values. Asforfeeding, FBtreatmentproducedonlya As for feeding, FB treatment produced only a slight increment of protein in breast and a decrease of fat and ash in thigh meat. Total PUFA and PUFA n-6 resulted lower in both thigh and breast meat of FB groups compared to SB (P<0.01)

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