Macronutrient Requirements of Silvery-Black Porgy (Sparidentex hasta): A Comparison with Other Farmed Sparid Species

Silvery-black porgy (Sparidentex hasta) is recognized as one of the most promising fish species for aquaculture diversification in the Persian Gulf and the Oman Sea regions. In this regard, S. hasta has received considerable attention, and nutritional studies focused on establishing the nutritional requirements for improving diet formulation have been conducted during recent years. Considering the results from different dose–response nutritional studies on macronutrient requirements conducted in this species, it can be concluded that diets containing ca. 48% crude protein, 15% crude lipid, 15% carbohydrates and 20 KJ g−1 gross energy are recommended for on-growing S. hasta juveniles. In addition, the optimum essential amino acid profile for this species (expressed as g 16 g N−1), should be approximately arginine 5.3, lysine 6.0, threonine 5.2, histidine 2.5, isoleucine 4.6, leucine 5.4, methionine + cysteine 4.0 (in a diet containing 0.6 cysteine), phenylalanine + tyrosine 5.6 (in a diet containing 1.9 tyrosine), tryptophan 1.0 and valine 4.6. Moreover, the optimum dietary n-3 long chain polyunsaturated fatty acids and soybean lecithin are recommended to be 0.8% and 6%, respectively. The maximum replacement of fish meal with soy protein is recommended to be between 16.5% and 27.3%. In addition, different vegetal oil sources are also recommended for partial and almost complete replacement of fish oil in diets. Although the nutritional requirements in terms of macronutrients have been established under laboratory conditions, the analysis of the available literature indicate that future studies need to be conducted using a more holistic approach under intensive farming conditions in which different nutrients or additives need to be tested under different rearing conditions for refining nutrient requirements in this species.info:eu-repo/semantics/publishedVersio

Hemato-Immunological and plasma biochemical responses of silvery-black porgy (Sparidentex hasta) fed protein and essential amino acid deficient diets

A six-week feeding trial was conducted to evaluate the effects of protein free (PF) and essential amino acid deficient (EAAD) diets on the physiological responses of silvery-black porgy (Sparidentex hasta) juveniles. Three experimental diets were formulated: a control diet in which 60% of dietary nitrogen was provided by intact protein (fish meal) and 40% by crystalline AA [(blends of essential amino acids (EAA) and none essential amino acids (NEAA)]; an essential amino acid deficient diet in which 60% of dietary N was provided by intact protein, whereas the rest was provided by NEAA; and a protein free (PF) diet, which based on carbohydrate sources. Fish fed the PF and EAAD showed signs of anemia including lower red blood cells counts, hemoglobin and hematocrit levels than control group. Plasma lysozyme activity and complements C3 and C4, as well as total immunoglobulin levels were drastically reduced in fish fed PF and EAAD diets. Plasma and liver alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and alkaline phosphatase were significantly increased, but superoxide dismutase was decreased in fish fed PF and EAAD diets. Plasma total protein, albumin, high density lipoprotein, calcium and inorganic phosphorous significantly decreased in fish fed PF and EAAD diets. The information obtained from this study testing to extreme diets (EAAD and PF diets) may serve for better understanding the impact of protein nutritional imbalances in fish.info:eu-repo/semantics/acceptedVersio

Growth Performance, Hemato-Immunological Responses, and Digestive Enzyme Activities in Silvery-Black Porgy (Sparidentex hasta) Fed Dietary Bovine Lactoferrin

An 8-week study was conducted to evaluate three different diets supplemented with bovine lactoferrin (LF) at 0 (control), 800, and 1200 mg LF kg−1 diet on somatic growth, hemato-immunological parameters, antioxidant status, and digestive enzyme activities in silvery-black porgy (Sparidentex hasta) juveniles. Fish fed the 800 mg LF kg−1 diet had higher growth performance and feed utilization parameters than the other groups. Hematological and liver antioxidant parameters were not affected by dietary LF supplementation. Fish fed the 800 mg LF kg−1 diet had higher plasma lysozyme activity values than the other groups. Total protease activity was higher in fish fed LF-supplemented diets than the control group. Results indicated that diet supplemented with 800 mg kg−1 for 8 weeks enhanced somatic growth performance, lysozyme activity, and proteolytic digestive enzyme activities in S. hasta, as well as improving feed efficiency parameters like the protein efficiency and feed conversion ratios.info:eu-repo/semantics/acceptedVersio

Effects of dietary protein and essential amino acid deficiencies on growth, body composition, and digestive enzyme activities of silvery-black porgy (Sparidentex hasta)

Abstract A 6-week feeding trial was conducted to evaluate the effects of protein-free (PF) and essential amino-acid-deficient (EAAD) diets on the growth performance and digestive enzyme activities of silvery-black porgy (Sparidentex hasta) juveniles. Three experimental diets were formulated: a control diet in which 60% of dietary nitrogen was provided by intact protein (fish meal) and 40% by crystalline AA [(blends of essential amino acids (EAA) and none essential amino acids (NEAA)]; an essential amino-acid-deficient diet in which 60% of dietary N was provided by intact protein, whereas the rest was provided by NEAA and a protein-free (PF) diet, based on carbohydrate sources. Survival rates in fish fed the EAAD and PF diets were lower than in fish fed the control diet. Weight gain in fish fed with EAAD was 5.6 g lower than fish fed with the control diet. Furthermore, fish fed the PF diet lost weight and their final body weight was 12.2 g lower than the control group. Fish fed the PF diet had the highest whole-body moisture, but the lowest whole-body protein, lipid, threonine, aspartic acid, glutamic acid, and serine levels. Digestive pancreatic enzyme activities including trypsin, lipase, α-amylase, and carboxypeptidase A significantly decreased in fish fed EAAD and PF diets. The information obtained from this study testing two extreme diets (EAAD and PF) may serve for better understanding the impact of protein and EAA nutritional imbalances in fish performance

Dietary soybean lecithin affects growth performance, fillet biochemical composition and digestive enzyme activity in Sparidentex hasta juvenile

An eight-week study was conducted on silvery-black porgy (Sparidentex hasta) juveniles to evaluate four isoproteic, isolipidic and isoenergetic different diets (50% crude protein, 20% crude lipids, 18.5 MJ kg−1) containing graded levels of soybean lecithin (SBL) (0, 30, 60 and 90 g kg−1 diet) at the expense of fish oil (FO). Fish fed the 60 g SBL kg−1 diet had significantly higher weight gain (32.4%) and feed intake (8.8 g fish−1) than the control group (SBL 0) (P < 0.05). The fillet fatty acid (FA) profiles were correlated with the FA profile of the experimental diets. Fish fed with SBL-supplemented diets had higher fillet phosphatidylcholine levels than the control group (P < 0.05). Plasma total immunoglobulin was higher in fish fed 60 and 90 g SBL kg−1 diets than in the other groups (P < 0.05). Total protease activity was higher in fish fed the 90 g SLB kg−1 diet than other treatments (P < 0.05). Results indicated that substitution of dietary FO with SBL diet up to 67% (60 g SLB kg−1 diet) improved somatic growth performance and profoundly affected the fillet fatty acid profile in silvery-black porgy juveniles