The effects of dietary EPA and DHA fortification on lipolysis activity and physiological function in juvenile black sea breamAcanthopagrus schlegeli(Bleeker)

Abstract

Hatchery-reared juvenile black sea bream Acanthopagrus schlegeli (Bleeker) are characterized by high lipid storage and low levels of highly unsaturated fatty acids in their bodies. In the present study, we assessed the effects of dietary forti®cation of the diet with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on the improvement of physiological activity. Black sea bream 50 days old with an average weight of 0.02 g were reared for 50 days on either a control diet (commercial diet) or a commercial diet forti®ed with 3% EPA and DHA. The forti®cation with EPA and DHA reduced lipid storage in adipocytes in the intraperitoneal cavity, but decreased muscle lipid level. Consequently, the total lipid level decreased in the bodies of the ®sh. The proportions of EPA and DHA in muscle, liver and adipocytes were markedly increased by diet forti®cation, and the EPA and DHA proportions did not differ from those of wild ®sh. The cell diameter of adipocytes was reduced by EPA and DHA forti®cation. Liver function and resistance to air-dipping were improved by forti®cation. The results of a starvation test revealed the ef®cient mobilization of lipid reserves in response to energy demands prior to protein exhaustion in the EPA/ DHA-enriched group. The results implied that increasing the incorporation of dietary EPA and/or DHA should be considered in the larval stage of black sea bream culture.

Ontogeny and nutritional control of adipogenesis in zebrafish (Danio rerio)

“…These reductions in body mass, length, and lipid content in 35 dpf zebrafi sh starved for 7 days were not accompanied by appreciable increases in mortality or lethargy. These large reductions in lipid content and body size in starved zebrafi sh are similar in magnitude to starvation-induced reductions previously observed in other teleost fi shes ( 26,35 ).…”

“…Like their mammalian counterparts, adult fi sh adipocytes store neutral lipid in the form of triacylglycerol, and these stores are mobilized during periods of nutrient deprivation (26)(27)(28). Fat deposition in fi sh is also sensitive to nutrient availability ( 29,30 ), and the enzymatic machinery responsible for fat deposition and mobilization in fi sh appears to be similar to that found in mammals ( 27 ).…”

<b>Total lipid nutritional quality of the adipose tissue from the orbital cavity in Nile tilapia from continental aquaculture

“…It is interesting to note that the values of 18:2n-6 in the feed were between 32.99 and 37.57%. The diets provided to fish can affect the lipid content, especially the fatty acid composition (Om et al, 2001).…”

“…Diets given to fish directly affect the muscle composition, especially regarding the lipid content and the composition of fatty acids (Om et al, 2001). The importance of lipids in diets for aquatic organisms is associated with the increase of palatability, the improvement of the muscle tissue texture and the fatty acids profile (Martino & Portz, 2006;Martino & Takahashi, 2001).…”

In vivo Analysis of White Adipose Tissue in Zebrafish

“…Deposition and mobilization of lipid within teleost WAT is altered in response to nutritional manipulation (Fig. 2), suggesting the energy storage functions of WAT have been conserved between teleosts and mammals (Albalat et al , 2007; Bellardi et al , 1995; Company et al , 1999; Flynn et al , 2009; Imrie and Sadler, 2010; Om et al , 2001). Furthermore, histological analysis reveals evolutionarily conserved morphological features of teleost adipocytes, including large cytoplasmic LDs, caveolae, and close association with capillaries (Flynn et al , 2009; Imrie and Sadler, 2010).…”