INFLUENCE OF THE FEEDING LEVEL ON GROWTH, FEED CONVERSION, PROTEIN EFFICIENCY AND CHEMICAL COMPOSITION OF JUVENILE EUROPEAN SEA-BASS (Dicentrarchus labrax)

AbstractThe objective of the present study was to examine the effect of diets with descending fish meal (FM) inclusion levels and the addition of salt to the diet containing the lowest FM level on growth performances, feed conversion ratio, and intestinal solute carrier family 6 member 19 (SLC6A19) and oligopeptide transporter 1 (PEPT1) transcript levels, in freshwater-adapted European sea bass (Dicentrarchus labrax). We first isolated by molecular cloning and sequenced a full-length cDNA representing the neutral amino acid transporter SLC6A19 in sea bass. The cDNA sequence was deposited in GenBank database (accession no. KC812315). The twelve transmembrane domains and the ‘de novo’ prediction of the three-dimensional structure of SLC6A19 protein (634 amino acids) are presented. We then analysed diet-induced changes in the mRNA copies of SLC6A19 and PEPT1 genes in different portions of sea bass intestine using real-time RT-PCR. Sea bass were fed for 6 weeks on different diets, with ascending levels of fat or descending levels of FM, which was replaced with vegetable meal. The salt-enriched diet was prepared by adding 3 % NaCl to the diet containing 10 % FM. SLC6A19 mRNA in the anterior and posterior intestine of sea bass were not modulated by dietary protein sources and salt supplementation. Conversely, including salt in a diet containing a low FM percentage up-regulated the mRNA copies of PEPT1 in the hindgut. Fish growth correlated positively with the content of FM in the diets. Interestingly, the addition of salt to the diet containing 10 % FM improved feed intake, as well as specific growth rate and feed conversion ratio.

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Evaluation of the Effects of the Enriched-Organic Diets Composition on European Sea Bass Welfare through a Multi-Parametric Approach

Journal of Marine Science and Engineering ◽

10.3390/jmse8110934 ◽

2020 ◽

Vol 8 (11) ◽

pp. 934

Author(s):

Pierluigi Carbonara ◽

Walter Zupa ◽

Isabella Bitetto ◽

Sébastien Alfonso ◽

Mariano Dara ◽

...

Keyword(s):

Organic Contaminants ◽

Growth Parameters ◽

Physiological State ◽

Dicentrarchus Labrax ◽

Principal Component ◽

Sea Bass ◽

Feed Conversion ◽

Fish Welfare ◽

European Sea Bass ◽

Conventional Diet

Three groups of European sea bass (Dicentrarchus labrax) were fed for seven months, with either a conventional diet or two different organic diets, which contain organic vegetables and a natural antioxidant compound. The two organic diets differed themselves in terms of raw proteins, fish oil, and lipid contents. Sea bass welfare condition was assessed in relation to these three diets, using 16 different indicators. These were: swimming activity (recovery test, muscle activity), haematological and serological stress indicators (haematocrit, haemoglobin, red-blood-cell count, cortisol, glucose, lactate), aspecific immunity parameter (lysozyme), indicators of exposure to organic contaminants (7-ethoxyresorufin-O-deethylase and glutathione-S-transferase), and growth parameters (weight gain, specific growth rate, feed conversion ratio, protein efficiency ratio, and hepato-somatic index). Most of these parameters individually did not give consistent responses, but their integration can provide an accurate evaluation of the fish welfare conditions among the three diet experimental groups. The multiparametric approach outlined a comprehensive picture of sea bass physiological state. The principal component analysis and the multi-criteria-decision-analysis were found to be useful tools for an integrated fish welfare assessment, highlighting that the best welfare condition was achieved in the experimental group fed with the protein-rich organic diet.

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Effect of stocking density and feeding level on energy expenditure and stress responsiveness in European sea bass Dicentrarchus labrax

Aquaculture ◽

10.1016/j.aquaculture.2009.11.007 ◽

2010 ◽

Vol 298 (3-4) ◽

pp. 245-250 ◽

Cited By ~ 96

Author(s):

I. Lupatsch ◽

G.A. Santos ◽

J.W. Schrama ◽

J.A.J. Verreth

Keyword(s):

Energy Expenditure ◽

Dicentrarchus Labrax ◽

Stocking Density ◽

Sea Bass ◽

European Sea Bass ◽

Feeding Level ◽

Stress Responsiveness

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Performance, nutrient retention efficiency, total ammonia and reactive phosphorus excretion of growing European sea-bass (Dicentrarchus labrax, L.) as affected by diet processing and feeding level

Aquaculture ◽

10.1016/s0044-8486(97)00256-1 ◽

1998 ◽

Vol 161 (1-4) ◽

pp. 55-65 ◽

Cited By ~ 38

Author(s):

R Ballestrazzi ◽

D Lanari ◽

E D'Agaro

Keyword(s):

Dicentrarchus Labrax ◽

Nutrient Retention ◽

Sea Bass ◽

European Sea Bass ◽

Retention Efficiency ◽

Feeding Level ◽

Phosphorus Excretion ◽

Total Ammonia ◽

Reactive Phosphorus

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Dietary Cinnamon Successfully Enhanced the Growth Performance, Growth Hormone, Antibacterial Capacity, and Immunity of European Sea Bass (Dicentrarchus labrax)

Animals ◽

10.3390/ani11072128 ◽

2021 ◽

Vol 11 (7) ◽

pp. 2128

Author(s):

Mahmoud M. Habiba ◽

Ebtehal E. Hussein ◽

Ahmed M. Ashry ◽

Ahmed M. El-Zayat ◽

Aziza M. Hassan ◽

...

Keyword(s):

Growth Hormone ◽

White Blood Cells ◽

Dicentrarchus Labrax ◽

Sea Bass ◽

Feed Conversion ◽

Feeding Trial ◽

European Sea Bass ◽

High Production ◽

Growth Promoting ◽

Vibrio Spp

Dietary cinnamon has several bioactive compounds with growth-promoting and immunomodulation potential and is suggested for finfish species. This study evaluated the inclusion of cinnamon at 0, 10, 15, and 20 g/kg in European sea bass (Dicentrarchus labrax) diets. After 90 days, the highest final weight, weight gain, specific growth rate, protein efficiency ratio, and the lowest feed conversion ratio were seen in fish treated with 10 g/kg (p < 0.05). Further, the measured growth hormone in the blood indicated that fish treated with 10 g/kg had a higher level than fish 0 and 20 g/kg. After the feeding trial, fish treated with cinnamon at varying levels had higher lipid content than fish before the feeding trial (p < 0.05). Lower Vibrio spp. and Faecal Coliform counts were observed in fish treated with cinnamon than fish fed a cinnamon-free diet (p < 0.05). The hematocrit level was markedly (p < 0.05) increased in fish fed cinnamon at 10 g/kg compared to the control without significant differences with fish fed 15 and 20 g/kg. Hemoglobin was significantly increased in fish treated with cinnamon at 10, 15, and 20 g/kg compared to fish fed a cinnamon-free diet (p < 0.05). Red and white blood cells (RBCs and WBCs) were meaningfully (p < 0.05) increased in fish treated with cinnamon compared with the control. Markedly, fish treated with cinnamon had higher serum total lipids than the control with the highest value in fish treated with 15 g/kg (p < 0.05). The lysozyme activity was markedly higher in fish treated with 15 g cinnamon/kg than fish fed 0, 10, and 20 g/kg (p < 0.05). Moreover, phagocytic activity was significantly higher in fish treated with cinnamon at 10, and 15 g/kg than fish fed 0 and 20 g/kg (p < 0.05). In conclusion, dietary cinnamon is suggested at 10–15 g/kg for achieving the high production and wellbeing of European sea bass.

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