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Fillet Yield (fillet + yield)
Selected AbstractsFillet yield and fat content in common carp (Cyprinus carpio) produced in three Austrian carp farms with different culture methodologiesJOURNAL OF APPLIED ICHTHYOLOGY, Issue 5 2009C. Bauer Summary The fat content and fillet yield of common carp (Cyprinus carpio) from three carp farms were investigated with respect to pond management and overall climatic conditions. The mean fat content of the trimmed fillet varied from 2.7 to 6.9% and differed significantly among the three facilities (P < 0.001). It is suggested that differences in the fillet fat content may be based on the climatic conditions as well as the different management strategies (feeding, stocking biomass). The mean fillet yield was calculated as 34.0,39.0%. No significant correlation between fish weight and fillet yield (, = ,0.16) was found. Results suggest that producing smaller fish for fillets of serving size may lead to a higher production and conclude with lower production risks and costs. [source] Dietary Lipid Utilization by Juvenile Summer Flounder Paralichthys dentatusJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 2 2003T. Gibson Gaylord The ability of juvenile summer flounder Paralichthys dentatus to utilize dietary lipid as energy, and the effect of dietary lipid on weight gain and body composition was investigated in a 12-week feeding trial. Diets were formulated to provide 55% crude protein from herring meal and casein. Menhaden oil was added to produce diets with 8, 12, 16 or 20% total lipid while providing 16.0 kJ available energy/g dry diet. The diet containing 20% total lipid supplied 16.7 kJ available energy/g dry diet due to the high levels of protein and lipid. An additional diet was included to reproduce currently available commercial diet formulations for flounder, providing 55% crude protein supplied solely from herring meal and 16% total dietary lipid. Juvenile summer flounder (initial weight 23 g) were stocked into triplicate aquaria in a closed, recirculating system maintained at 20 C. Fish were fed 2% of body weight each day divided into two equal feedings. Upon termination of the study, effects of dietary lipid on weight gain, body condition indices, and proximate composition were determined. Weight gain (96,149% of initial weight), feed efficiency ratio values (0.43,0.48). fillet yield, and whole-body composition all were unaffected by dietary lipid level. High levels of dietary lipid did increase the lipid content in the finray muscle, as fish fed diets containing 16 and 20% dietary lipid had significantly higher lipid levels than fish fed the diet containing 8% lipid. No apparent protein sparing effect of lipid was observed. These data indicate that currently available commercial feeds for summer flounder may be over-formulated and show a need for further research to determine specific and accurate nutritional information for this species. [source] Genetic covariation in production traits of sub-adult black bream Acanthopagrus butcheri after grow-outAQUACULTURE RESEARCH, Issue 11 2005Robert G Doupé Abstract Predicting the suitability and reliability of traits associated with juvenile growth as indirect selection criteria for choosing future broodstock requires accurate and repeatable estimates of genetic (co)variation for growth traits at different ages. We compared juvenile wet weight of black bream Acanthopagrus butcheri (Munro) at 6 months of age with wet weight, dressed weight, fillet yield and gonad weight in tagged individuals at 18 months of age, following 12 months of farm grow-out. Fish survival and tag retention was high, and there was significant among-family variation for all traits. The phenotypic correlations among wet weight, dressed weight and fillet yield at 18 months of age were very high (0.93,0.97) and similar to their genetic correlations (0.96). Importantly, the phenotypic correlations between wet weight at 6 months and wet weight, dressed weight and fillet yield at 18 months were high (0.63,0.65), and so too were their genetic correlations (0.66,0.73), indicating the potential for using wet weight in the hatchery as a selection criterion for improved weight and meat yield of fish at harvest. Gonad weight shared little or no phenotypic or genetic correlation with these other traits, suggesting that selection for faster growing fish will not affect fecundity or sexual maturation rate. It appears, however, that cultured black bream do become sexually mature more rapidly than wild fish, as 78% of all fish harvested in this study had developing or mature gonads, whereas less than 50% of fish in wild populations are reproductively mature by the same age. Precocious sexual development may lead to uncontrolled spawning in grow-out ponds and a potential loss of selection gains. [source] Do changes in Atlantic salmon, Salmo salar L., fillet fatty acids following a dietary switch represent wash-out or dilution?AQUACULTURE RESEARCH, Issue 13 2003Test of a dilution model, its application Abstract The fatty acid compositions of fish tissue lipids usually reflect those of the feed lipids, but few attempts have been made to predict the way in which the profiles change or assess the time required for the fatty acid profile to stabilize following a dietary change. The present focus on the influences of vegetable oils and fish oils on the fatty acid compositions and sensory attributes of fish fillets increases the interest in the ability to make such predictions. A dilution model was tested using data for the influences of feed oils (rape/linseed (V) vs. sand-eel (F)) and dietary fat concentrations (ca. 30% (H) vs. ca. 20% (L)) on the body growth and fatty acid compositions of the fillets of Atlantic salmon, Salmo salar L., parr and post smolt. Fish given HV or LV feeds during freshwater rearing (mass increase from ca. 19 g to ca. 130 g) were switched to HF and LF feeds following parr,smolt transformation. The changes in fillet percentages of 18:1, 18:2 (n-6) and 18:3 (n-3) during 98 days of on-growing in seawater (mass increase from ca. 130 g to ca. 380 g) conformed closely to predictions made on the basis of the dilution model. Model applications require information about the proportionate increase in fillet fat over time, but the relative changes in body mass can be used as a surrogate provided that both fillet yield (as a % of body mass) and fillet fat percentage change little over time. This is not the case for small salmon, but does seem to apply to larger salmon as they approach harvest size. This means that, for large salmon, ratios of changes in body mass can be substituted for ratios in the quantitative change in fillet fat without the introduction of a large error in the prediction of the change in fillet fatty acid profile following the introduction of a novel feed. [source] | ||||||||||