Sand eel

Several terms have been used to describe this phenomenon, namely, biomagnification, bioconcentration, and bioaccumulation. However, the pesticide is not always concentrated or magnified as it moves up to the food chain, so the latter term is preferable (Nakatsugawa and Nelson, 1972). For example, dieldrin residue in cod at 0.009 ppm (whole fish bases) was less than in the sand eel, the major diet of the cod, at 0.016 ppm. Dieldrin residue in a macrozooplankton (crustacea) at 0.16 ppm was higher than in any of the fish examined... 

M, menhaden SM, speciaiiy processed marine oil (menhaden) R pilchard C, capelin H, herring A, anchovy CL, cod liver MA, mackerel HM, horse mackerel NR Norway pout S, sprat SA, sand eel. 

SSCP analysis has been found useful for the authentication of various types of seafood. As shown in Table 5.2, a considerable number of fish species, shrimps, and mollusks could be identified by SSCP of mitochondrial or nuclear genes. As SSCP gives very good results for short DNA segments, species identification of products containing severely degraded DNA (e.g., canned tuna) may be easier to achieve by SSCP than by RFLP (Rehbein et al., 1999). In a study of fish meal authentication, SSCP and RFLP-SSCP allowed differentiation between meals produced from a number of fish species, including two closely related sand eel species (Rehbein, 2002). 

Fig. 3. a Whole body fractional rates of protein synthesis and oxygen consumption of cod after a single meal of sand eels, b Absolute rates of protein synthesis of cod liver (O) and stomach ( ) from the same animals as in a. (Data from Lyndon et al. in prep.)... 

Fig. 20. a Results from the simultaneous measurements of oxygen consumption and whole body absolute rates of protein synthesis of cod made from starving animals and at various time points after feeding sand eels (Lyndon et al. unpubl.). b Relationship between mean absolute rates of protein synthesis and mean oxygen consumption for fasted, continuously fed and fasted crabs at 3, 9 and 16 h after a single meal. (Houlihan et al. 1990b) c Relationship between absolute rates of protein synthesis and oxygen consumption for Mytilus edulis (Hawkins et al. 1989)... 

As with meat, the main production of whole fish does not offer any scope for the decanter, but the bulk production of fish meal certainly does. Fish meal is a coarsely ground powder, high in protein, made from the cooked flesh of fish. Though formerly important as a fertilizer, fish meal is now primarily used in animal feed. The oily fish, such as menhaden, anchovy, herring, sand eel and pilchard, are the main source offish meal and its companion product, fish oil. To be processed into meal, chopped fish is fed by a screw conveyor through long steam cookers. The cooked mash is then pressed to remove water and oil. 

C Borch-Jensen, A Staby, J MoUerup. Supercritical fluid chromatographic analysis of a fish oil of the sand eel (Ammodytes sp.). J High Resol Chromatogr 16 621—623,1993. 

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