Red Tilapia Research Articles

Efficacy of Feed-Based Genome-Free Bacterial Vaccine Against Aeromonas hydrophila Infection in Red Tilapia (Oreochromis sp.)

Aeromonas hydrophila causes motile Aeromonas septicemia (MAS), a disease with a high mortality rate in tilapia culture. Feed-based vaccines with the incorporation of inactivated whole-cell bacteria into the feed offer promising tools to control MAS. Currently, the incorporation of genome-free bacteria as bacterial vaccine through the implementation of SimCells® technology into the feed has become a particular interest. Background/Objectives: This study investigates the efficacy of a feed-based vaccine incorporating genome-free A. hydrophila (FBV-GFAH) against MAS infection in red tilapia. Methods: The vaccine was prepared and delivered at 5% fish body weight for three consecutive days in weeks 0 (prime vaccination) and 2 (first booster vaccination), orally. Throughout a five-week experimental period, the immune-related genes (IL-1β, MHC-II, CD4, IgT, and IgM) expression in the hindgut and head kidney of the fish was determined using RT-qPCR assay. Lysozyme (serum) and overall IgM (serum, gut lavage, and skin mucus) productions were also detected. Results: Fish vaccinated with FBV-GFAH showed a significant (p ≤ 0.05) improvement in relative percent survival compared with unvaccinated fish following bacterial challenge. FBV-GFAH induced the expression of immune-related genes in the hindgut and head kidney, especially after booster vaccination. Furthermore, serum lysozyme activity and overall IgM production in serum, skin mucus, and gut lavage were also significantly (p ≤ 0.05) improved in the FBV-GFAH vaccinated fish than the unvaccinated fish. Conclusions: This study showed that FBV-GFAH is a promising feed-based vaccine technology to control MAS in cultured tilapia.

Growth, biochemical indexes, and intestinal microbiota response of red tilapia (Oreochromis spp.) under different densities and feeding frequencies in the land-based aquaculture tank

Red tilapia (Oreochromis spp.) has been favored by farmers in recent years because of its superior growth performance and competitive market price, but there is a lack of experimental data related to growth and health of red tilapia in land-based aquaculture tanks. In this study, red tilapia (initial weight 27.62 ± 2.43 g) was cultured with three stocking densities (30, 40, or 50 fish/m3, named 30F,40F and 50F) in the culture mode for 60 days, including two feeding frequencies (2 or 3 times/day, named 2 T and 3 T), and various growth and metabolic parameters were assessed along with the intestinal microbiome analysis. The 30 fish/m3 groups achieved the better weigh gain rate and specific growth rate (p < 0.05). The growth rate and condition factor of 40F groups were close to those of 30F groups, the yield of 40F groups were not significantly different from that of 50F groups (p > 0.05), and it had the highest survival rate (p < 0.05). The 3 T groups has a higher growth rate and yield but also has a higher rate of feed conversion (p < 0.05). The 30F groups had higher lipase levels, but a higher fat content in this group, more lipids were observed in the liver, and resulted in higher blood glucose levels (p < 0.05). The 40F groups showed healthier physiological and biochemical indicators, as its total cholesterol, lysozyme and antioxidant enzymes levels were similar to those of the 30F groups (p > 0.05), alkaline phosphatase, amylase and trypsin levels were higher than those of the other groups, and aspartate transaminase levels were the lowest (p < 0.05). The 50F groups had higher cortisol, alanine transaminase and malondialdehyde levels, lower lysozyme and digestive enzyme activities, and blood cell infiltration in the liver (p < 0.05). In terms of different feeding frequencies, the 3 T groups had higher crude protein content, catalase and total superoxide dismutase levels, wider villus width and lower blood glucose level, while the 2 T groups had higher triglyceride, total cholesterol, lysozyme, alkaline phosphatase and some digestive enzymes activities (p < 0.05). From the perspective of intestinal microbiota. The 40F groups had a better intestinal flora, and 40F-3T groups observed a better balance of flora, while 40F-2T groups had more digestion-related flora. Considering the growth rate, health status, and yield, the optimum culture condition was determined to be stocking density of 40 fish/m3, and feedings 3 times/day were recommended. The experiment provided theoretical basis and experimental data for red tilapia culture in land-based aquaculture tank mode.

Comparative effects of curcumin, nano curcumin and their combination on reproductive traits and spawning performance of red tilapia (Oreochromis Niloticus X O. Mossambicus)

Curcumin, the main polyphenol component of turmeric powder, has garnered increasing attention as an effective supplement in fish diets. A comparative trial was conducted to evaluate the impacts of dietary supplementation with different forms of curcumin (free, in combination, or nanoparticles) on hemato-biochemical parameters, reproductive capacity, and related gene expressions of red tilapia (Oreochromis niloticus x O. mossambicus) broodstock. Fish (n = 168) were fed an isonitrogenous (30% CP), isocaloric (18.72 MJ kg − 1) diet containing basal diet (Control), 60 mg kg-1 of either free curcumin (Cur), curcumin/nano-curcumin blend (Cur/NCur), or nano-curcumin (NCur) for 56 days. Red tilapia broodstock (155 ± 5.65 g) were stocked at a male: female ratio of 1:3. Blood samples and gonads were collected to assess hemato-biochemical parameters, reproductive capacity, and related gene expression at the end of the feeding trial. The results indicated that the values of hematological parameters (RBCs, WBCs, hemoglobin), total protein, albumin values, and reproductive hormones (T, LH, and FSH) were significantly increased, while liver function enzymes were decreased in the NCur group (P < 0.05). Reproductive performances (GSI, gonad maturation, total number of fry per female) were significantly improved in the NCur group compared with those in other groups (p < 0.05). The expression of reproductive genes (CYP19A1A, FSHR, LHR, FOXL2A, ESR1, ESR2A, and PGR) were significantly up‐regulated in the gonads of fish fed NCur. Collectively, feeding red tilapia diets containing NCur led to noticeably better results followed by Cur/NCur blend, then free Cur compared to the control diet. These results indicate the superiority of NCur over its free or blended form, suggesting that a diet containing about 60 mg/kg of NCur is beneficial for enhancing hemato-biochemical parameters, improving reproductive performance, and enhancing the gonadal architecture of red tilapia.

Aquaponics for Biological Regeneration of Water Quality in the Red Tilapia (Oreochromis sp.) Farming Systems and Its Impact on the Ecuadorian Consumer's Perception

Aquaponics for Biological Regeneration of Water Quality in the Red Tilapia (Oreochromis sp.) Farming Systems and Its Impact on the Ecuadorian Consumer's Perception

Effect of Crossbreeding on Fecundity, Growth Performance, and Heterosis of Black Tilapia, Red Tilapia, and Mozambique Tilapia Reared in Earthen Ponds in West Java, Indonesia

Graphical Abstract Highlight Research The crossbred performance of the four tilapia strains showed diverse heterosis values, with some being better, worse, or the same as their parents. Crossbred of black tilapia produced the best growth and fecundity performance. A hybrid of Mozambique tilapia and black tilapia showed the highest mid-parent heterosis value on growth traits but produced negative heterosis on fecundity, biomass, and survival traits. Crossbred of black tilapia and Mozambique tilapia have the potential to be used as candidates for cultivation and performance improvement through selection, although there are depressions and crossover advantages that are not prominent. Abstract Increased tilapia production is challenged by genetic decline. Hybridization efforts for performance improvement through a selection of the best parent and strain pairs were a promising option. The objective of this study was to evaluate the crossing of black tilapia, red tilapia, and Mozambique tilapia against the performance of fecundity, growth, and survival and estimate the value of heterosis. The experimental design used a completely randomized design with 3 replications with the treatment of different populations of crosses. The rearing activities were carried out in earthen ponds for 150 days with a stocking density of 10 fish/m2. The parameters observed included egg fecundity, growth, survival, and the value of heterosis. The results showed that the fecundity and growth values of crossbred black tilapia were significantly higher than others (p&lt;0.05). The highest survival rate was shown by crossing pure strains of red tilapia. The hybrid of Mozambique tilapia and black tilapia (♀ MJ x ♂ NW) showed the highest mid-parent heterosis value on growth characters but produced negative heterosis on characters, fecundity, biomass, and survival. Overall, the crossbred of black tilapia (♀BS x ♂ NW) performed better than the inbred strains, with positive mid-parent heterosis in all characters measured. These results indicate that crossbreeding has the potential to be used as a candidate for cultivation and performance improvement through selection, although there were depressions, and the superiority of the crosses was not prominent.

Effects of hydrogen peroxidase-inactivated vaccine against Streptococcus agalactiae infection in red tilapia (Oreochromis sp.) via different routes of administration

Hydrogen peroxidase-inactivated vaccines have recently developed in controlling infectious diseases in aquaculture. The present study aimed to compare the efficacy of the hydrogen peroxidase-inactivated Streptococcus agalactiae vaccine via different delivery routes (injection, immersion, and oral administration) in red tilapia (Oreochromis sp.) without using adjuvant. Fish were randomly divided into 4 groups including G1: Control treatment (without vaccine), G2: vaccine-based diet (oral administration), G3: vaccinated by immersion and G4: vaccinated by injection. After 6 weeks of the experiment, fish were intraperitoneally injected with S. agalactiae and the mortality was recorded in 14 days. The results showed that lysozyme activity was differentially increased according to the delivery routes of vaccine, organs and time of sampling. However, the specific antibody levels in all vaccinated groups were only increased in week 6 post-vaccination. After the challenge test with S. agalactiae, the serum lysozyme levels in G3 and G4 were significantly higher than the control group (G1), while the total white blood cells and specific antibody levels were significantly increased in G2 and G4 compared to the control (G1). Similarly, the hydrogen peroxidase-inactivated vaccine statistically reduced the cumulative mortality in G2 (35.29%) and G4 (28.95%) compared to G1 (44.12%) after injected with the S. agalactiae. These results showed that the vaccine delivery routes by oral administration or injection may decrease the pathogen and show better protection for red tilapia than the immersion method. Further studies will be investigated to improve the efficacy of hydrogen peroxidaseinactivated vaccine via using different adjuvants.

The regulatory effects of water probiotic supplementation on the blood physiology, reproductive performance, and its related genes in Red Tilapia (Oreochromis niloticus X O. mossambicus)

Probiotics are becoming increasingly popular as eco-friendly alternatives in aquaculture. However, there is limited research on their impacts on the reproductive efficiency of Red Tilapia (Oreochromis niloticus x O. mossambicus) broodstock. Therefore, this experiment aimed to explore the combined effects of selective probiotics Bacillus subtilis and B. licheniformis (BSL; 1:1) added to water on blood hematology, serum metabolites, gonadal histology, reproductive performance, and reproductive associated genes in Red Tilapia broodstock. Tilapia broodfish weighing 140–160 g were stocked in four treatment groups: control (T0), and the other three groups were added different levels of BSL to the water as follows: T1 (0.01 g/m3), T2 (0.02 g/m3), and T3 (0.03 g/m3), respectively. Results indicate that BSL administration significantly improved RBCs, hemoglobin, hematocrit, MCH, and MCHC, with the highest improvement seen in the T3 group (P < 0.05). BSL added to the fish water significantly enhanced serum protein fractions (total protein, albumin, and globulins), while AST, ALT, ALP, creatinine, uric acid, and glucose were significantly diminished in a dose-dependent way (P < 0.05). Adding 0.02–0.03 g/ m3 of BSL resulted in higher antioxidant status (superoxide dismutase and catalase) compared to other groups (P < 0.05). Testosterone levels were higher in T3 than in other groups (P < 0.05). All female hormones (LH, FSH, estradiol, and progesterone) were substantially augmented by the addition of BSL. Additionally, the BSL groups exhibited higher GSI, HSI, VSI (male only), egg diameter (mm), mean number of fry/fish, and mean fry weight (g) compared to the control group (P < 0.05). Expression of reproductive-associated genes (vasa, nanos1a, nanos2, dnd1, pum1, AMH, and vtg) were significantly up-regulated in the gonads of fish in the 0.03 g/m3 treatment. The histological gonadal structure exhibited that BSL improved gonad maturation in both genders of Tilapia fish. Overall, adding a mixture of B. subtilis and B. licheniformis (0.03 g/m3 water) can accelerate reproductive performance in Red Tilapia through up-regulation of reproductive genes and enhance the health profile.

Diverse carbon sources impact the biofloc system in brackish groundwater altering water quality, fish performance, immune status, antioxidants, plasma biochemistry, pathogenic bacterial load and organ histomorphology in Florida red tilapia

A 75-day rearing trial was completed to investigate the effectiveness of different biofloc systems (BFT) on the water quality, growth performance and health status of Florida red tilapia (FRT) grown in brackish groundwater (BGW). The trial consisted of the control and three types of BFT using different carbon sources (CS), starch (ST), rice bran (RB), and wheat bran (WB) in triplicate, expressed as BF-0, BF-ST, BF-RB, and BF-WB, respectively. Fish weighing 4.98 ± 0.01 g/fish were stocked in 250-L tanks at an initial stocking density of 25 fish. The findings demonstrated significant reductions in inorganic nitrogen by-product (NH3 and NO2) levels in all BFT groups compared to the control, with an increase in floc volume and floc nutritional value, in the BF-ST and BF-RB groups. Furthermore, fish in the BF-ST and BF-RB groups showed significant improvements in fish growth indices (final weight, weight gain, and FCR). Fish in the BFT groups showed significant improvement in kidney function indices and plasma lipids with no significant changes in liver enzyme activity compared to the control. Lower stress markers (glucose and cortisol) and higher digestive enzyme activity (lipase and protease), innate immune parameters and antioxidants were reported in fish of the BF-ST and BF-RB groups compared to the control fish. Histopathological inspection revealed that the BF-ST fish exhibited healthier livers and shared healthier intestines with BF-RB fish compared to the control group. In conclusion, RB is an appropriate CS with BGW for desert aquaculture due to its availability, inexpensiveness, and comparable outcomes with ST.

The Impact of Silica Addition on Floc Volume Density in the Biofloc System for Juvenile Red Tilapia (Oreochromis niloticus)

Biofloc technology is a solution to the problem of waste management in aquaculture. Biofloc systems are beneficial because they not only reduce inorganic nitrogen waste from feed residues and fish excrement but also produce flocs. The aim of this research is to determine the effect of silica addition on floc volume density in the biofloc system for juvenile red tilapia. The research was conducted from January to March 2024 at the Center of Excellence in Science and Technology (PUI-PT) for Functional Nano Powder at Padjadjaran University. This study uses a Completely Randomized Design (CRD) experimental method with four treatments and three replications. The treatments used were (A) control, (B) 15 ppm silica, (C) 20 ppm silica, and (D) 25 ppm silica. The study used cylindrical containers with a capacity of 19 liters filled with 15 liters of water, a stocking density of 10 juvenile red tilapia per cylinder, with the juvenile measuring 3-4 cm and weighing 3-4 g. The parameters observed were floc volume density and water quality. The data on floc volume density and water quality were analyzed descriptively. The results showed that the addition of 25 ppm silica in the biofloc system was the best treatment for floc volume density. This was evidenced by the results in treatment D (25 ppm) achieving a floc volume density of 26.5 ml/L, which falls into the dense category. Therefore, the addition of silica concentration in the biofloc system can increase floc volume density.

Intra-species differences shape differences of enrofloxacin residues and its degradation products in tilapia: A precise risk assessment

The increasing use and abuse of antibiotics in agriculture and aquaculture necessitates a more thorough risk assessment. We first advocate a precise assessment that subdivides the assessment scope from interspecies to intraspecific levels. Differences in ENR residues and degradation within the intraspecific category were simultaneously explored. This study chose red and GIFT tilapia, both belonging to the intra-specific category of tilapia, for an enrofloxacin (ENR) exposure experiment. Red tilapia had a lower area under the curve (AUC) representing drug accumulation, indicating a notably shorter withdrawal period (7 days) compared to GIFT tilapia (31.4 days) in the edible parts. While four potential transformation pathways were proposed for ENR in tilapia, red tilapia had fewer detected degradation products (6 items) than GIFT tilapia (10 items), indicating a simpler transformation pathway in red tilapia. Predictive assessments using the Toxtree model revealed that of the four extra degradation products in GIFT tilapia, two may possess carcinogenic and mutagenic properties. Overall, differences were observed in ENR residues and degradation within the intraspecific category, with red tilapia presenting lower risks than GIFT tilapia. This work suggests a new strategy to perfect the methodology for antibiotic risk assessment and facilitate systematic antibiotic administration management in the future.

Integrated biofloc technology in red tilapia aquaculture: Salinity-dependent effects on water quality, parental stock physiology, reproduction, and immune responses

The study examines the impact of integrated biofloc technology (BFT), different salinity levels, and their combined effects over 90 days on various physiological parameters. The investigation includes growth performance and feed utilization, water quality, the chemical composition of biofloc and fish, digestive enzymes, reproductive performance, stress and biochemical indicators, and antioxidant-immune responses in red tilapia (Oreochromis spp.) broodstock. The fish were initially weighed (males: n = 270; 104 ± 0.96 g; females: n = 270; 93.2 ± 0.66 g) and subsequently divided into 12 treatment groups (6 for males and 6 for females) spread across 36 separate tanks (3 tanks per treatment; 45 fish per treatment; 15 fish/tank). The treatments involved three salinity levels (18, 28, and 36 ppt) in both clear water (CW) and BFT systems. The outcomes demonstrated that fish in the 36 ppt salinity with BFT treatment demonstrated significant improvements (P < 0.05) in growth parameters (final body weight, weight gain, and specific growth rate, feed intake, and feed conversion ratio). The condition factor in BFT groups increased in all salinity situations. The survival rates of broodstock were consistently high in all experimental conditions The study found that BFT and salinity significantly impacted (P < 0.05) whole body contents (moisture, protein, lipid, and ash) in both males and females. Water quality parameters showed variations between BFT and CW, with notable impacts (P < 0.05) on dissolved oxygen and pH. The BFT and salinity influenced digestive enzyme activities (protease, amylase, and lipase) and reproductive performance (males) and the 36 ppt salinity with BFT recorded the highest values. The hemato-biochemical and antioxidant-immune responses were also impacted by BFT and salinity exposure. The study highlights the potential benefits of incorporating BFT into red tilapia aquaculture systems, particularly in optimizing growth, health, and reproductive performance under various salinity conditions, which can enhance sustainable intensification, disease control, and environmental stewardship.

Enhancing Florida red tilapia aquaculture: biofloc optimization improves water quality, pathogen bacterial control, fish health, immune response, and organ histopathology across varied groundwater salinities.

Freshwater scarcity poses challenges to aquaculture worldwide, including countries like Egypt. In this study, we investigate the feasibility of integrating underground saline water (USW) with varying salinities into a Biofloc (BFT) system for desert mariculture of Florida red tilapia (FRT) and its impacts on water quality, fish performance and health. Four BFT treatments (C/N ratio = 15) were examined in triplicate using four salinity levels 0 ppt, 12 ppt, 24 ppt and 36 ppt, expressed as S0, S12, S24 and S36, respectively. For 75 days, a total of 12 fiberglass tanks (each 250L-1 water) were used to store FRT fry (average weight of 1.73 ± 0.01g/fish). The fish were fed an experimental diet (protein/fat = 30/5) and an additional carbon source of rice bran. The results revealed that group S12 showed better growth indicators, higher survival rate, lower FCR, and lower ammonia levels, while group S0 exhibited lower growth indicators (final weight, weight gain, and specific growth rate) than all groups. The serum kidney, liver, and antioxidant indices performed better in the S12 group. At 12 ppt, the immune-related parameter (IgM) increased by 22.5%, while the stress parameter (cortisol) decreased by 40.8% compared to the S0 group. The liver and intestinal histopathological results revealed that the S12 and S24 groups performed better. Pathogenic bacterial load counts favored the S24 group, which had the lowest number among the groups studied. The recommended salinity for FRT cultivation in USW and BFT is 19.94-20 ppt, determined by polynomial regression of FW and FCR.

Effects of Ascorbic Acid Dietary Supplementation on the Red Tilapia (Oreochromis spp.); Broodstock Growth, Reproductive Efficiency, Immunity, and Gonadal Fatty Acids Profile

Effects of Ascorbic Acid Dietary Supplementation on the Red Tilapia (Oreochromis spp.); Broodstock Growth, Reproductive Efficiency, Immunity, and Gonadal Fatty Acids Profile

The Ability of the Red Tilapia (Oreochromis sp.) to Tolerate Different Concentrations of Unionized Ammonia and Water Salinity Levels

The Ability of the Red Tilapia (Oreochromis sp.) to Tolerate Different Concentrations of Unionized Ammonia and Water Salinity Levels

Mosquito larvae (Aedes aegypti), Francisella orientalis and tilapia (Oreochromis sp.): Relationship of host-pathogen-carrier in disease transmission

Piscine francisellosis, caused by the bacterium Francisella orientalis, poses a significant threat to various warm water fish. The coexistence of mosquito larvae, bacteria, and fish in aquatic ecosystems suggests the potential for interconnected pathogen/disease transmission. While mosquito larvae have been recognized as carriers of Francisella spp. in humans diseases, their role in transmitting francisellosis to aquatic animals remained unexplored. This study investigates whether mosquito larvae (Aedes aegypti) can uptake F. orientalis and transmit the disease to hybrid red tilapia (Oreochromis sp.). To assess uptake, naive mosquito larvae were exposed to F. orientalis-contaminated water or to experimentally infected tilapia, and specific PCR and culture techniques were employed to monitor F. orientalis. Rearing conditions at 25 °C and 30 °C were also examined to explore temperature influences. Results confirmed the presence of F. orientalis in larvae from both contaminated water and infected fish experiments. To assess their potential to transmit the disease, F. orientalis-exposed mosquito larvae were fed to naive tilapia. The challenged tilapia developed typical granulomas in the kidney and spleen after ingesting the F. orientalis-harboring mosquito larvae. Histopathological changes were more pronounced in fish kept at 25 °C than those at 30 °C. Corresponding with histopathology, all fish (n = 10) cultured at 25 °C were positive for F. orientalis-specific PCR assays, compared to 7 out of 10 samples at 30 °C. This study reveals, for the first time, that mosquito larvae can uptake F. orientalis and act as mechanical carriers for disease transmission in tilapia. Preventive measures such as mosquito control and water treatment might aid in eliminating larvae and contaminated bacteria, and reducing infection risks of piscine francisellosis. Additionally, this suggests that mosquito larvae could serve as a model for further studying the transmission of other aquatic animal diseases.

Genotyping of red tilapia strains in Central Luzon Philippines targeting ESR1 gene

Tilapia is an economically important commodity worldwide. Marker-assisted selection (MAS) has been practiced in livestock culture to ensure the selection of a specific trait that will benefit the culture system. This study assessed the allelic variation in six red tilapia strains in Central Luzon, Philippines. Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) was done to evaluate the genotypes of six strains of red tilapia using intron one portion of the chromosome one of the estrogen receptor 1 (ESR1) gene. The target gene was amplified using primers designed in previous study and then subjected to RFLP using PvuII restriction enzyme. Single Nucleotide Polymorphisms (SNPs) were also evaluated in six DNA sequences. Results showed that 18 red tilapia samples were found to be of the AA genotype. Aligned sequences of the 122 bp ESR1 gene revealed that among six red tilapia strains, there are 117 identical pairs, three transversional pairs, and three transitional pairs. The SNPs observed can be used to identify restriction enzymes that discriminate different genotypes in the target gene. Association studies can be done to determine the genotypes that are linked to specific traits in cultured animals.

Effect of sea purslane (Halimione portulacoides) as feed additive on larval rearing of red tilapia (Oreochromis aureus × Oreochromis mossambicus)

Effect of sea purslane (Halimione portulacoides) as feed additive on larval rearing of red tilapia (Oreochromis aureus × Oreochromis mossambicus)

HISTOMORPHOMETRY OF SPLEEN RED TILAPIA (OREOCHROMIS NILOTICUS) CULTIVATED WITH DIFFERENT AERATIONAND FILTRATION

Cultivation of red tilapia (Oreochromis niloticus) requires good water quality. Physiological processes and organ structures can be disrupted when water quality including dissolved oxygen, water temperature, pH, salinity and ammonia exceeds the normal threshold. Aeration and filtration in fish farming can help improve water quality which affects the improvement of physiological processes and spleen function of red tilapia. The study was purposed to analyze the use of aerators, filters and a combination of both on the histomorphometry and structure of the spleen of red tilapia. This study used a completely randomized design with a 2×2 factorial arrangement. Each main factor consists of two levels, such as aeration i.e., single aeration and double aeration and filtration i.e., without filter and with filter. The experimental fish in the study were 24 red tilapia fish which were divided into four treatment groups, which included single aeration without filter, double aeration without filter, single aeration with filter, and double aeration with filter. The results showed that the interaction between aeration and filters had no significant effect (P&gt;0.05) on spleen weight, Relative Spleen Weight (RSW), red pulp diameter, white pulp diameter, melanomacrophage center (MMC) diameter, and MMC cell diameter. The conclusion of this study was that the aeration, filters and combination of aeration and filters could maintain the chemical quality of water so there was no adverse effect on the histomorphometry and structure of the spleen of red tilapia

Curcumin’s effects on growth indices, histological scores, blood metabolites, redox state, immunity, and antioxidant-related genes of red tilapia (Oreochromis sp.)

Curcumin, a polyphenol, targets multiple signaling molecules and shows activity at the cellular level, supporting its various health benefits. Thereafter, the present study examines the effects of different doses of dietary curcumin on growth indices, feed efficiency, serum metabolites, redox (oxidation) status, immunity, histological assessment, and antioxidant-related genes in red tilapia (Oreochromis sp, Oreochromis aureus x O. mossambicus). A total of 1200 red tilapia with an average weight of 19.1±0.03 g were distributed in 12 cement ponds (3×3.5×1m). Each treatment was assigned three pounds (n=100 replicates). For 60 days, fish were fed baseline diets containing 0, 0.4, 0.6, and 0.8 g of curcumin/kg of diet. The treated fish showed increased body weight and SGR (specific growth rate) compared to the T0 group (P<0.05). Curcumin in the diet significantly improved weight gain, percentages, and FCR (feed conversion ratio), with a dose-dependent effect (P < 0.05). Curcumin supplementation showed no influence on feed intake, fish mortality, or survival rate (P >0.05). The curcumin-treated fish groups improved tissue structure in hepatocytes, pancreatic lumens, hepatic blood sinusoids, and intestine tissue layers, particularly the mucosal layer. The T0.8 group had reduced liver enzymes (AST and ALT) and greater total protein and albumin levels (P<0.05). The T0.6 and T0.8 groups showed significantly lower MDA levels than the other groups (P < 0.05). Curcumin groups demonstrated significantly higher antioxidant indices (CAT, GPx, and SOD) compared to the basal diet (P<0.05). Curcumin administration resulted in significant improvements in IgM and lysosome levels (P<0.05). All supplemented groups had considerably (P<0.05) higher levels of SOD, CAT, and GPx mRNA than the control group. Consequently, administering 0.6–0.8 g/kg of curcumin to red tilapia (Oreochromis sp.) diets may improve the fish’s growth, health, tissue composition, and antioxidant response.

Dietary lysophospholipid improves growth performance, antioxidant capacity and immunity response of red tilapia (Oreochromis niloticus × O. mossambicus)

Lysophospholipids (LPL) are usually used as emulsifiers in fish nutrition because of their ability to ameliorate nutrient digestibility and lipid metabolism. The present study aims to assess the effects of a commercial dietary lysophospholipid on growth performance, feed utilization, antioxidant activity, innate immunity and biochemical indices of red tilapia (Oreochromis niloticus x O. mosambicus) fingerlings. Five isonitrogenous (35.8% CP) and isocaloric (18.7 MJ kg−1) diets were prepared as follows: two control diets coded as C1 and C2, containing 2 and 1% soybean oil, respectively. The other three diets were coded as LPL1, LPL2 and LPL3, and were formulated by supplementing the C2 diet with 0.1, 0.2 and 0.3% lysophospholipid. The fingerlings of red tilapia (2.13 ± 0.42 g fish−1) were fed the diets for 70 days. The highest significant (p < 0.05) final weight and weight gain were recorded in LPL2. The best values of feed efficiency and protein efficiency (PER)were in all fish groups fed LPL in their diets (p < 0.05). Protein productive value (PPV) showed the highest result in LPL3 (p < 0.05). Lysozyme activity showed the best result in LPL3 (p < 0.05). The highest values of alternative complement activity (ACH50) and total immunoglobulin (Ig) were in LPL3 and LPL2 (p < 0.05). The best results of superoxide dismutase (SOD) and catalase activity were recorded in LPL3 (p < 0.05). The lowest values of triglycerides (TG) and total cholesterol (CHO) were detected in LPL1 and LPL2 (p < 0.05). Thus, the inclusion of 0.2% of the commercial lysophospholipid in red tilapia diets enhanced the growth performance, feed utilization, innate immunity, antioxidant activity and lipase activity, and reduced CHO and TG of red tilapia fingerlings.