We examined the effects of the following seven experimental diets that varied in the concentration of inactivated cells of Enterococcus faecalis (Ef) and mannan oligosaccharides (MOS), on Rainbow Trout Oncorhynchus mykiss: control (C) diet (no Ef and no MOS), diet E0.25% (2.5 g/kg Ef), diet E0.5% (5 g/kg Ef), diet M0.25% (2.5 g/kg MOS), diet M0.5% (5 g/kg MOS), diet EM0.25% (2.5 g/kg Ef + 2.5 g/kg MOS) and diet EM0.5% (5 g/kg Ef + 5 g/kg MOS). Rainbow Trout, initially weighing 36.27 ± 0.42 g (mean ± SD) were distributed into fourteen 60‐L glass tanks at a stocking density of 35 fish per tank. Each diet was hand‐fed to duplicate groups of fish twice daily for a 12‐week period. After the feeding test, an intraperitoneal injection challenge test of Aeromonas salmonicida was conducted over 14 d. Resulting data were submitted to a multivariate analysis of variance. Weight gain increased significantly (P < 0.05) in E0.25%, M0.25%, and EM0.5% experimental groups compared with the control. Specific growth rate was significantly higher (P < 0.05) in fish fed E0.25%, M0.25%, and EM0.5% diets compared with fish fed the C diet. Feed gain ratio and protein efficiency ratio were significantly improved (P < 0.05) in fish fed the EM0.5% diet compared with fish fed the C diet. Feed intake, protein efficiency ratio, protein retention, and the apparent digestibility coefficient recorded slight differences within experimental groups. Hematocrit value and phagocytic activity were significantly higher (P < 0.05) in fish fed E0.25%, E0.5%, M0.5%, EM0.25%, and EM0.5% diets compared with fish fed the C diet. Except for fish in the E0.25% group, fish in all other experimental groups showed a significantly higher (P < 0.05) mucus weight compared with those in the C group. After the challenge test, cumulative mortality and frequency of A. salmonicida were significantly decreased (P < 0.05) in all experimental groups compared with the C group. In conclusion, dosage and single or combined supplementation of Ef and MOS are factors that significantly affect fish performance.

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This research study is focused on the lipid requirements of Petenia splendida (0.65 ± 0.19 g) juveniles. Fish were fed with trout commercial diet (Silver Cup™ - 45% protein and 16% lipids), as control diet - CD (which is usually used to feed this species at commercial scale), and four isoproteic (45% crude protein) diet formulated with different lipid levels (5, 10, 15 and 20%). Diets were administered for 60 days by triplicate per treatment. Our results showed that fish fed with 10, 15 and 20% lipid levels were significantly higher (P < 0.05) in average weight and total length. Same treatments were significantly lower (P < 0.05) in terms of FCR compared to those shown in 5% and CD. However, fish fed 20% lipid level, showed a significant decrease in WG and a significant (P < 0.05) increase in FCR compared to those shown in 15% lipid level. Fish fed with 15% showed the highest weight gain and the lowest FCR compared with the rest of the treatments. Lipid efficiency ratio (LER) showed significant (P < 0.05) differences among experimental groups. Compared to other diets containing lipid levels (5, 10, and 20%) fish fed 15% diet recorded the lowest protein and lipid content in whole body. Additionally, based on second order polynomial regression analysis of WG, it was demonstrated that 16.2% lipid provides an optimal growth for P. splendida.

The aim of this study was to assess quality of SSF (Solid State Fermented) lupin with Lactobacillus plantarum 299v, and its effects (on growth, feed utilization, digestibility and immunity) of juvenile Atlantic salmon (S. salar), when used as fish meal replacer. Five experimental diets were formulated to provide 40% crude protein and 21% dietary lipid (dry matter basis) with the raw or fermented lupin meal-based protein source replacing fish meal at 15% and 30%. Triplicate groups of fish (averaging 3.53 ± 0.05 g) were fed with experimental diets for 8 weeks. Fermentation process modified nutrient profile of lupin meal and enriched it with lactic, citric and acetic acids. Fish in the FL15% group showed a higher (P < 0.05) final body weight, weight gain, FCR, SGR, and PER compared to those of C group. Apparent digestibility coefficient (ADC) of protein and Nitrogen-free extract showed a significantly higher values in FL15% experimental group, compared to those shown in C group. Fish in the FL15% group showed a higher (P<0.05) lysozyme activity and leucocyte respiratory burst compared to that shown by fish samples in the C experimental group; phagocytic activity did not record differences among experimental groups. In conclusion, replacement of fish meal by raw or fermented lupin meal did not compromise growth, apparent digestibility coefficients and immune status of juvenile Atlantic salmon and even improve fish performance when supplemented at 15%.

We search for positive utility impact on the invasive species Pterygoplichthys spp. The optimal level of replacement of sardine meal (SM) by Pterygoplichthys spp. meal (PLM) in practical feeds for fry of Nile tilapia (Oreochromis niloticus) was evaluated. We evaluated six experimental diets: 50% PLM-50% SM, 60% PLM-40% SM, 70% PLM-30% SM, 80% PLM-20% SM, 90% PLM-10% SM and 100% PLM-0% SM. In a recirculation system, 270 sex-reversed tilapia fry were used (0.7 ± 0.1 g). Diets were administered in triplicate and the experiment lasted 56 days with sampling every 14 days. There were no statistical differences in growth. At the end of the experiment, the SGR, ADG, CF, WG, DFI, FCR and PER were determined without significant differences (P > 0.05) between treatments, but there was a tendency that could indicated higher WG and PER in the 90% PLM-10% SM treatment (93.56 ± 0.43% and 8.44 ± 1.18 g, respectively). All survival rates were higher than 90% with no significant differences. Additionally, there were no statistical differences in the chemical composition of the whole fish, while apparent digestibility coefficients of protein (81-90%) and lipids (87-93%) also showed no significant differences. We concluded that 100% PLM can replace 100% SM in feeding fry of O. niloticus without affecting their survival, growth or chemical composition or the apparent digestibility of nutrients.

This datasheet on Rachycentron canadum covers Identity, Overview, Associated Diseases, Pests or Pathogens, Distribution, Dispersal, Biology & Ecology, Environmental Requirements, Natural Enemies, Impacts, Uses, Management, Genetics and Breeding, Economics, Further Information.

In the past decade, different groups of additives (probiotics, oligosaccharides, and plant extracts) have been widely researched and used in worldwide aquaculture. Recently, other groups, such as biopolymers (e.g., poly‐β‐hydroxybutyrate) with prebiotic properties, have been investigated. Among biopolymers, the use of pure polyhydroxyalkanoate (PHA; composition = 95–100%) as a feed additive in aquaculture has not been studied yet. Therefore, the aim of the present study was to research the effects of four supplementation levels of pure PHA on growth, survival, feed and nutrient utilization, apparent digestibility coefficients (ADCs), and hematology of Nile Tilapia Oreochromis niloticus. Five isonitrogenous and isolipidic diets were designed, including a control (C) diet without PHA supplementation. Remaining diets were supplemented with the following levels of PHA: PHA 0.1% (basal diet + 0.1% PHA), PHA 0.5% (basal diet + 0.5% PHA), PHA 1.0% (basal diet + 1.0% PHA), and PHA 2.0% (basal diet + 2.0% PHA). After a 70‐d feeding test period, the PHA 0.5% and PHA 1.0% experimental groups showed significantly higher final body weight, weight gain, specific growth rate, lipid efficiency and productive value, and ADCs of lipid and energy compared to those of the C group. Protein efficiency ratio was significantly higher in fish fed the PHA 0.1%, PHA 0.5%, and PHA 1.0% diets compared to the C group. Protein productive value significantly increased in the PHA 1.0% group. The ADC of protein was significantly higher in fish fed diets supplemented with any level of PHA compared to C fish. Regarding hematological parameters, hematocrit value showed a significant increase in fish fed PHA 0.1% compared to the C group. Leukocyte composition (%) did not show significant differences among experimental groups. Based on polynomial regression analysis, the optimum inclusion levels of PHA in Nile Tilapia diets were 0.82–0.92% for growth performance, 1.0–1.1% for nutrient utilization, 1.0–1.2% for ADCs, and 1.34% for hematocrit. Cost–benefit ratio analysis revealed nonsignificant but numerical differences among experimental diets. Results suggest that pure PHA, when supplemented at 0.1, 0.5, 1.0, or 2.0%, has certain positive effects on growth, nutrient and feed utilization, and ADCs without compromising Nile Tilapia hematology or health.

Expansion of aquaculture industry is evidently accompanied by an urgent necessity of aquaculture feed production. Traditionally, fish meal (FM) and soybean meal (SBM) have been the primary protein source ingredient in aquaculture diets.  However, over exploitation of these commodities has conducted to their unsustainability. Hence, research of unconventional protein alternatives has emerged. Mushroom meal is one of them. To date, mushroom meals have been investigated when supplemented in low levels in aquaculture diets. Furthermore, effects of diets supplemented with mushroom meals have assessed different parameters such as, haematology, immunity, anti–bacterial & anti–oxidant activities, and heat stress. Present study, is aimed to study the effects of graded levels of dietary pink oyster mushroom (Pleurotus djamor) meal (POMM), in growth, feed efficiency, protein utilization, digestive enzymes activities and whole body proximate composition of Nile tilapia (Oreochromis niloticus) fingerlings. Experimental design included a control diet (POMM0) formulated with soybean meal, as main protein source, and four diets designed with increasing levels of POMM: 25%(POMM25); 50%(POMM50); 75%(POMM75); and 100%(POMM100). Experimental diets and final whole body were submitted to a proximate composition analysis. Growth, feed efficiency, protein utilization, and digestive enzyme activities were assessed.  Compared to POMM0 and POMM25, weight gain (WG), and specific growth rate (SGR), significantly (P< 0.05) decreased in fish fed POMM50, POMM75 and POMM100%. Feed conversion ratio (FCR), protein efficiency ratio (PER) and survival rate (SR) were not significantly affected by experimental diets. Daily feed intake (DFI), and daily protein intake (DPI), decreased as POMM increased in diets. Compared to POMM0 experimental group, condition factor (K), showed a significantly higher value in fish fed POMM50, and POMM100 experimental diets. Crude fiber of final whole body of POMM100 resulted significantly higher (P< 0.05) compared to that shown in fish fed the rest of experimental diets. Acid and alkaline proteases, trypsin, chymotrypsin, leucine aminopeptidase and amylase of Nile tilapia fingerlings, were not significantly affected by experimental diets. Compared to fish fed POMM0 and POMM25 diets, experimental fish fed POMM50, POMM75, and POMM100 showed a reduction of lipase activity. In conclusion, a POMM level higher than 25% affects growth and lipase activity. While a POMM level higher than 50% affects fiber content in whole body of final fish.