Growth response and body composition of sharpsnout sea bream (Diplodus puntazzo) fed a high energy diet with different protein levels.

A study was undertaken to determine the effect of a high energy diet with two different protein levels on growth, feed efficiency and whole body composition of sharpsnout sea bream (Diplodus puntazzo). Two isoenergetic diets (24.1-24.7 MJ Kg-1 dry weight) with two different protein levels (46.7 and 52.5 % dry weight) were fed to satiety to duplicate groups of 300 fish (initial body weight 27.7 \ub1 0.2 g) for 94 days. At the end of the experiment, the fish fed 52.5 % protein showed a statistically higher (P < 0.05) daily intake rate (DIR) of feed. Feed conversion rate (FCR) was similar among groups. Whole body composition was similar among treatments while the high enrgy level of the diets significantly modified lipid and moisture content in comparison with fish at the beginning of the experiment. Protein efficiency ratio (PER), gross protein efficiency (GPE) of fish fed 46.7 % protein diet were statistically higher than those for the other diet. It may be concluded that the diet with a lower protein level has given better protein utilization and a protein sparing effect but tended to result in reduced weight gain and feed intake, when compared with diet containing higher protein levels

High-pressure Raman spectroscopy on low albite

The pressure dependence of the Raman spectrum of low albite, NaAlSi3O8, has been investigated from 0.0001 to 10.4&nbsp;GPa, at room temperature, on a single crystal compressed hydrostatically in a diamond anvil cell. The Raman vibrational features move to higher wavenumbers \u3c5i with increasing pressure, due to the decrease in the unit-cell volume corresponding to a drastic shrinkage of the framework. The slopes \u394\u3c5i/\u394P of the four investigated bending modes (i.e. at 478, 507, 578 and 815&nbsp;cm 121, at 0.0001&nbsp;GPa) show evident changes at ~6.5 and ~8.5&nbsp;GPa. This behaviour may be ascribed, in the absence of phase transitions, to the evolution of the compressional mechanisms at the atomic scale found in previous high-pressure studies on albite (mainly by X-ray diffraction), through a model based on tilts of rigid tetrahedra. The Raman data of this study allowed also to bracket the pressure range in which the occurrence of the first change in the compressional behaviour was found by X-ray diffraction

Monitoring of common sole Solea Solea (L) captive broodstock from Northern Adriatic Sea over consecutive spawning seasons

The high nutritional quality of common sole Solea solea increases its value for the fishery industry and for the aquaculture sector. To ensure the expansion of its production, it is necessary to implement farming and broodstock management technique to produce high quality eggs and larvae. This work summarizes eight years of study on reproductive performances, growth and parental contribution of a common sole broodstock from the Mediterranean-North Adriatic Sea. The broodstock (11 females and 13 males) reached the peak of fecundity after 5/6 years of captivity, with a production of 296,476 and 376,541 7 103 of total eggs kg 121 female with a fertilization rate of 31.6 \ub1 18.3 and 41.9 \ub1 23.8 %, respectively. Results shows that variations in temperature cycles are pivotal for a successful breeding season, and body condition during the first 3 years of captivity was the most important parameter positively correlated to parental contribution for both males and females. Parental contribution was assessed by eight species-specific microsatellite loci during the first 3 years of reproduction. Although the two sexes displayed different temporal trends, parentage assessment demonstrated an overall increase in the number of active breeders. However, only 13 couples out of 50 produced the 70.4 % of the larvae in year 5, confirming the same reproduction behavioural pattern in Mediterranean common sole than that observed both in Senegalese sole and in common sole of Atlantic origin. This work provides valuable data needed to understand the mechanisms behind the maturation characteristics of this species and support future strategy for the establishment and management of Mediterranean common sole aquaculture

High-pressure Raman spectroscopy of Ca(Mg,Co)Si2O6 and Ca(Mg,Co)Ge2O6 clinopyroxenes

In situ high-pressure Raman spectra were collected on four pyroxenes, with composition CaCoSi2O6, CaMgSi2O6, CaCoGe2O6 and CaMgGe2O6, up to P = 7.6 and 8.3 GPa for silicates and germanates, respectively. The peak wavenumbers \ucf\u85i increase almost linearly with pressure; the slope d\ucf\u85i/dP is more pronounced for the modes at higher wavenumbers, and higher in germanates than in silicates. No phase transition or change in the compressional behaviour was observed within the investigated P-range. The strong dependence of the peak position with pressure of the high energy stretching modes is due to the high sensitivity of the vibrational frequencies probed by Raman spectroscopy to subtle changes in the tetrahedral deformation, which are overlooked by single-crystal X-ray diffraction

FRESHNESS QUALITY OF GILTHEAD SEA BREAM (Sparus aurata) REARED UNDER DIFFERENT FARMING CONDITIONS

Sensory and physico-chemical freshness indices (QI score, Torrymeter readings, pH and WHC) were evaluated in gilthead sea bream of commercial size reared in Italy in: land based facilities (recirculation systems), lagoons and net-cages. Fish were stored under ice for 0, 1, 3, 6, 9, 12 and 16 days: at each sampling time analyses were performed to determine the evolution of each freshness index within sea bream sources. Significant differences emerged among farming conditions following the application of the Quality Index Method. Torrymeter readings gradually decreased with the number of days of ice storage. pH values remained practically constant over the 16 days of storage. For WHC the effect of both time of storage and farming conditions was statistically significant

RANCIDITY DEVELOPMENT DURING FROZEN STORAGE OF FILLETS FROM GILTHEAD SEABREAM (Sparus aurata) REARED IN ITALY

Lipid oxidation indices (Free Fatty Acids-FFA, Peroxide Value-PV and Thiobarbituric Acid-TBA) were evaluated in frozen fillets from seabream reared in Italy in: land based facilities (recirculation systems), lagoons or net-cages. Statistically significant differences emerged among seabream sources for all indices. Quality loss related to rancidity seemed to have been affected by both storage time and culturing system

FRESHNESS QUALITY OF GILTHEAD SEA BREAM (Sparus aurata) REARED UNDER DIFFERENT FARMING CONDITIONS

Sensory and physico-chemical freshness indices (QI score, Torrymeter readings, pH and WHC) were evaluated in gilthead sea bream of commercial size reared in Italy in: land based facilities (recirculation systems), lagoons and net-cages. Fish were stored under ice for 0, 1, 3, 6, 9, 12 and 16 days: at each sampling time analyses were performed to determine the evolution of each freshness index within sea bream sources. Significant differences emerged among farming conditions following the application of the Quality Index Method. Torrymeter readings gradually decreased with the number of days of ice storage. pH values remained practically constant over the 16 days of storage. For WHC the effect of both time of storage and farming conditions was statistically significant

Valorizzazione della produzione ittica nazionale mediante valutazione dei rischi e standardizzazione della qualit\ue0

Il Ministero delle Politiche Agricole Alimentari e Forestali in data 5 dicembre 2006 ha emanato un bando (vedi allegato) per la presentazione di progetti di ricerca per l'attuazione dei programmi nazionali di ricerca per la pesca e l\u2019acquacoltura relativi agli anni 2005 e 2006 Il Progetto di ricerca ha il seguente titolo \u201cVALORIZZAZIONE DELLA PRODUZIONE ITTICA NAZIONALE MEDIANTE VALUTAZIONE DEI RISCHI E STANDARDIZZAZIONE DELLA QUALIT\uc0\u201d E' stato presentato per il seguente Codice tematico di riferimento:IGIENE E QUALITA\u2019 DEI PRODOTTI DELLA PESCA E DELL\u2019ACQUACOLTURA Il Coordinamento \ue8 a cura del Dipartimento di Morfofisiologia Veterinaria e Produzioni Animali (Universit\ue0 di Bologna) Il Responsabile Scientifico \ue8 il Prof. Pier Paolo Gatta Sono coinvolti: Istituto Nazionale di Ricerca per gli Alimenti e la Nutrizione \u2013 INRAN, con sede a Roma. Referente scientifico Dott.ssa Elena Orban); Federcoopesca (Federazione Nazionale Cooperative della Pesca). Presidente Dott. Massimo Coccia Lega Pesca (Associazione di categoria delle cooperative operanti nel settore dell'economia ittica). Presidente Ettore Ian\uec Durata complessiva: 24 mesi Finanziamento richiesto 400.000 euro Finanziamento approvato 320.000 euro Sommario del progetto I recenti regolamenti comunitari costituenti il cosiddetto \u201cpacchetto igiene\u201d, entrato in vigore il 1\ub0 gennaio 2006, hanno sancito che i pescatori professionali, come tutte le altre categorie di produttori primari, debbano adottare procedure in grado di garantire la sicurezza alimentare del loro prodotto e l\u2019osservanza della \u201cbuona prassi igienica\u201d durante tutte le operazioni di pesca e l\u2019introduzione del prodotto nella filiera commerciale (Reg 852/2004). Inoltre, \ue8 previsto che gli Stati membri della Comunit\ue0 Europea, promuovano l\u2019elaborazione di manuali nazionali di corretta prassi operativa in materia di igiene e di applicazione dei principi del sistema HACCP. Questo progetto di ricerca ha come obiettivo la valutazione del grado di applicabilit\ue0 di tali norme nella valutazione dei pi\uf9 importanti pericoli e rischi igienico-sanitari del prodotto pescato, congiuntamente alla messa a punto di un sistema standardizzato di controllo integrati per la caratterizzazione sensoriale e il miglioramento della qualit\ue0 e della freschezza del prodotto. A questo scopo, in collaborazione con associazioni nazionali di categoria del settore della pesca, verranno scelte aree geografiche e specie ittiche rappresentative di cui verranno individuati i rischi igienico-sanitari (contaminanti biologici, chimici e fisici) e i fattori che ne influenzano l\u2019intensit\ue0 (stagione e temperatura, manualit\ue0 a bordo). Congiuntamente a questo e sulla base delle procedure di lavorazione esistenti e delle attrezzature disponibili, verr\ue0 valutato come i processi produttivi influenzino la freschezza e come sia possibile migliorarla. A questo scopo, verr\ue0 utilizzata la metodica sensoriale QIM (quality index method). L\u2019intero processo di controllo e valorizzazione qualitativa del prodotto verr\ue0 valutato dal punto di vista economico allo scopo di determinare i costi e l\u2019eventuale impatto positivo che tali procedure possono esercitare sul consumatore. Lo studio dei rischi igienico-sanitari di determinate aree e specie ittiche fornir\ue0 un importante apporto scientifico per aiutare gli operatori della pesca a meglio comprendere e applicare in modo corretto e uniforme le nuove norme comunitarie sulla sicurezza dei prodotti ittici, nonch\ue9 per l\u2019elaborazione dei \u201cmanuali di corretta prassi igienica\u201d. Lo studio della freschezza permetter\ue0 la messa a punto di procedure operative per l\u2019analisi sensoriale e la valutazione della qualit\ue0 del prodotto fresco, fornendo agli operatori uno strumento efficace da utilizzarsi in \u201ccampo\u201d. La collaborazione con associazioni nazionali di categoria del settore della pesca permetter\ue0, nel medio periodo, un passaggio delle conoscenze agli operatori del settore per l\u2019utilizzo di ..

Nutritional traits of dorsal and ventral fillets from three farmed fish species

Dorsal and ventral fillet portions (DP and VP, resp.) of European sea bass (Dicentrarchus labrax, ESB), gilthead sea bream (Sparus aurata, GSB), and rainbow trout (Oncorhynchus mykiss, RBT) were analysed for proximate constituents, and fatty acid composition and content. Moisture and lipid content differentiated DP from VP in all species. Significant differences emerged between DP and VP from ESB for MUFA, PUFA, and DHA content. The n6/n3 ratio ranged from 0.22 (DP in RBT) to 0.38 (VP in GSB). The highest Hypocholesterolaemic/Hypercholesterolaemic fatty acid ratio pertained to DP and VP from RBT, and the lowest Peroxidisability Index to VP from GSB and ESB. The Index of Nutritional Quality for EPA + DHA was always higher in VP than in DP, that of RBT being especially interesting because associated with a lower energy value than that from ESB and GSB