Comparison of meat quality of tench, Tinca tinca , reared in extensive and semi-intensive culture systems

Abstract

SummaryThe aim of the study was to examine the production parameters and chemical composition of fillets in tench, Tinca tinca L., farmed in one of two systems: an extensive system based on only natural food (NF) available in the fish ponds; and a semi-intensive system based on natural food plus the addition of formulated feeds supplemented with various oils: fish (FO), rapeseed (RO), soybean (SO), or linseed oil (LO). Proper pond preparation resulted in a favourable amount and structure of natural food in all ponds. The rearing system had a significant influence on the tench yield, muscle lipid contents and fatty acid composition, and the supplemented feed influenced the fatty acid composition. The percentages of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acid and total highly unsaturated n-3 fatty acids (n-3 HUFA) were higher in the fish oil and the natural food groups than in the others. The n-3/n-6 ratio in the five dietary treatments was notably variable, and in any case higher in fillets than in the diets. In conclusion, the present study suggests that RO, SO and LO represent effective lipid sources for tench fed formulated diets. On the other hand, tench that fed on naturally available pond foods had a high content of n-3 HUFA in their muscle lipids, but poor growth parameters and low yields.

Effect of feeding various levels of poultry by-product meal on the blood parameters, filet composition and structure of female tenches (Tinca tinca)

“…Steffens and Wirth () reported lower values of the Σn‐3:Σn‐6 ratio in the fillets of tenches inhabiting ponds and using natural food (1.0), a combination of natural food and wheat (1.1), and feed (2.2). In a comparison of the Σn‐3:Σn‐6 ratio in feeds and fillets, the values are lower in the latter case, which is in accordance with the results of other studies (Jankowska et al., ; Ljubojevic et al., ). The Σn‐3:Σn‐6 ratio depends on various rearing factors, however, as was indicated by Steffens and Wirth () desired level can be obtained by implementing appropriate diet.…”

“…ratio in feeds and fillets, the values are lower in the latter case, which is in accordance with the results of other studies(Jankowska et al, 2006;Ljubojevic et al, 2014). The Rn-3:Rn-6 ratio depends on various rearing factors, however, as was indicated bySteffens and Wirth (2005) desired level can be obtained by implementing appropriate diet.Fish haematology is gaining increasing attention in fish farming because of its importance in the monitoring of the fish welfare status.…”

Comparison of body composition and sensory quality of wild and farmed whitefish (Coregonus macrophthalmus [Nüsslin, 1882])

“…In contrast, the lipid content of farmed C. macrophthalmus fillets was dominated by monounsaturated and polyunsaturated fatty acids, a result most convincingly explained by the composition of the trout diet fed to the farmed whitefish that contained a high proportion of unsaturated fatty acids. Similar findings have been reported for salmon Salmo salar (Bell et al, 1998(Bell et al, , 2010, trout Oncorhynchus mykiss (Brinker & Reiter, 2011), and tench Tinca tinca (Ljubojević et al, 2014), supplied with feeds containing optimal formulations of fish oil and suggesting that diet could be used to influence the fatty acid patterns of farmed whitefish in a desirable way (Orban et al, 2002(Orban et al, , 2003. In contrast, it is nearly impossible to exert any control on such factors in wild fish.…”

Effect of Different Feeding Levels of Plant‐ingredient‐based Feed on Fillet Fatty Acid Profile, Carcass Trait, and Sensory Characteristics of Indian Major Carps in Earthen Pond Polyculture

“…The total biomass gain increased with increasing feeding level up to 2% of body weight and plateaued thereafter. The effect of dietary FA on fillet FA profile of carp is well studied and a linear correlation exists between them (Ljubojević et al 2014). The plankton population and their class in the pond water in all feeding treatments were similar, indicating the adequacy of natural food production and its utilization by the fish.…”