Influence of food deprivation and high stocking density on energetic metabolism and stress response in red porgy, Pagrus pagrus L

Abstract

In the present study, the influence of high stocking density and food deprivation on red porgy (Pagrus pagrus L.) energy metabolism was investigated after 14 and 21 days assessing plasmatic, hepatic, and muscular parameters. Specimens were submitted to four different experimental conditions: (1) fed fish under low stocking density (4 kg m -3 , LSD-F); (2) food-deprived fish under low stocking density (LSD-FD); (3) fed fish under high stocking density (50 kg m -3 , HSD-F); and (4) food-deprived fish under high stocking density (HSD-FD). At plasmatic level, cortisol concentration enhanced in fish maintained under HSD condition, with higher effect in fed fish, whereas FD condition decreased values of lactate, protein, and triglycerides. In liver, significant increases in triglyceride levels, together with a decrease in glycogen values, were observed in FD specimens. Furthermore, a weak effect of density in fed fish was observed, with decreasing hepatic glycogen. In white muscle, aminoacid and triglyceride values diminished in FD group, while increased in specimens submitted to HSD condition. Our results suggested an enhancement in P. pagrus gluconeogenic and glycogenolytic potential when submitted to HSD and FD conditions to cope reallocation of metabolic energy due to these different stress situations.

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“…However, no mortality was observed in any of the selected stocking densities in our current study. Similar results have been reported for farmed fish cultured with good water quality, e.g., rainbow trout, sea bass, red porgy (Pagrus pagrus), African catfish (Clarias gariepinus), and Nile tilapia (Oreochromis niloticus) (Hengsawat et al, 1997;North et al, 2006;Sophie et al 2009;Laizcarrión et al 2012).…”

“…TG is also an important source of energy during acclimation to different stocking densities (Herrera et al, 2009;Laizcarrión et al, 2012). The increase in serum TG under high density conditions could be related to lipid mobilization to cope with an increased energy demand when GLU stores are drastically utilized (Sheridan and Mommsen, 1991;Albalat et al, 2005;Huising et al, 2006), as shown by our results.…”

Effect of Feeding with Different Dietary Protein Levels and Starvation on the Health, Nonspecific Immune Parameters, Behavior and Histoarchitectures of Fantail Goldfish (Carassius auratus L.)

“…This result was coordinated with that of Mommsen TP [44] who mentioned that serum glucose levels increased by fasting it may explained by fish trying to keep glucose concentrations during starvation by the increase of glycogenolysis and gluconeogenesis. Also Laiz-Carrión R, et al [45] found an enhancement in the gluconeogenic and glycogenolytic during starvation.…”

The influence of stocking density and food deprivation in silver catfish (Rhamdia quelen): A metabolic and endocrine approach

“…Stocking density is a stressor that activates stress responses in fish, which affect different metabolic enzymes related to lipid, carbohydrate and protein metabolism (Costas et al, 2008;Laiz-Carrión et al, 2012;Montero et al, 1999;Sangiao-Alvarellos et al, 2005a). Due to the diversity of stress response in fish (Barton, 2002), these effects appear to be speciesspecific and mainly dependent on the sensitivity of fish at high stocking density and the increase of social interactions at very low and/or very high stocking densities (Ellis et al, 2002;Montero et al, 1999;North et al, 2006).…”

“…Thus, fasting is frequently used to study whether a rhythm in glucose metabolism is independent of the effect of feeding since daily rhythms dependent on feeding should disappear in food-deprived animals (Polakof et al, 2007). In fish, the effects of fasting on daily changes of several plasma metabolites and hormones have been characterized in different species (Laiz-Carrión et al, 2012;Polakof et al, 2006;Sangiao-Alvarellos et al, 2005b). The metabolic responses to this situation vary depending on several factors such as age, size, and species displaying alterations in the carbohydrate, lipid, and protein metabolism in order to maintain homeostasis (Navarro and Gutiérrez, 1995).…”