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The aim of the present study was to evaluate music effects (Mozart, K525) on gilthead seabream Sparus aurata and investigate whether its response to music was differentiated when combined with different lighting conditions. Therefore, S. aurata (mean AE S.E. 1Á51 AE 0Á01 g) were reared in re-circulating water system under 80 and 200 lx and subjected to 2 and 4 h of music transmissions or to no music at all (control, ambient noise only). Underwater ambient noise of the equipment (e.g. pumps and aerators) in all experimental tanks was 121 dB re 1 mPa and music transmitted was set at 140 dB re 1 mPa. During the first 89 days of rearing, music resulted in enhanced growth. Nevertheless, at the end of the experiment (on day 117) no significant differences were found for body mass but music treatment resulted in more homogeneous fish populations than controls. Brain neurotransmitter levels were reduced especially when music transmission was combined with 200 lx. Feed utilization was significantly improved when fish were subjected to 4 h of music and 200 lx, while stomach proteolytic enzymes and intestine total carbohydrases were lower and higher, respectively, compared to controls. Some differences were also observed in liver and plasma fatty acids composition. The present results provide the initial evidence that music transmission under specific rearing conditions could have enhancing effects on S. aurata growth performance, at least at specific fish sizes. Moreover, the observed music effects on several aspects of fish physiology (e.g. digestive enzymes, fatty acid composition and brain neurotransmitters) imply that music could possibly provide even further enhancement in growth, quality, welfare and production.

The effects of different stunning/killing procedures on flesh quality of European sea bass were investigated: (1) anaesthesia with clove oil, (2) anaesthesia with 2-phenoxyethanol, (3) percussive stunning, (4) immersion in ice/water slurry, (5) chilling on ice and (6) anaesthesia with clove oil followed by immersion in ice/water slurry. Muscle pH values were significantly lower in sea bass anaesthetized or stunned by a blow to the head compared with fish immersed in ice/water slurry, chilled on ice or immersed in ice/water slurry after clove oil anaesthesia. Lightness was highest in sea bass anaesthetized by 2-phenoxyethanol or percussively stunned and lowest in ice-chilled fish. Redness and yellowness were highest in fish chilled on ice and lowest in fish anaesthetized with clove oil. Liquid loss, fat loss and shear values were not significantly different among the procedures. In general, lipid oxidation values during refrigerated or frozen storage did not significantly differ among treatment groups.Combination of clove oil anaesthesia followed by chilling on ice/water slurry appears to improve both flesh quality and welfare of sea bass, although the implementation of further studies is warranted to consolidate this finding.

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