Growth Performance Of Tilapia Research Articles

The efficacy of using pine (Pinus massoniana) pollen as an alternative to synthetic steroids in producing monosex male Nile tilapia (Oreochromis niloticus, L.)

AbstractSynthetic sex steroids are widely used to produce all‐male stocks in Nile tilapia (Oreochromis niloticus). However, there is a growing concern about the use of synthetic steroid hormones in fish as food. We investigated the efficacy of a natural sex hormone as an alternative to synthetic steroids in producing monosex male tilapia. Two‐day‐old fry were fed pine pollen powder at three different concentrations (0.5%, 1.0%, 1.5%) for 28 days and subsequently reared for 3 months to observe the efficacy of pine pollen as well as to optimize the concentration for sex reversal. As a positive control, same‐aged fry of three different commercial tilapia hatcheries were fed synthetic steroid and 17‐α‐methyl testosterone‐treated feed (60 mg/kg) for the same duration. Before analyzing the phenotypic sex, the fish were reared on untreated commercial feed for 90 days in separate tanks. The 1.0% pine pollen treatment yielded a mean of 92.50 ± 0.51% males among the progeny, higher than the mean (89.49 ± 0.25%) obtained from synthetic steroid treatments. This result demonstrates that pine pollen could be an effective compound for the direct masculinization of Nile tilapia. We also obtained a significant difference (p < 0.05) in the growth performance and survival of tilapia using the dietary allotment of pine pollen. Our study suggests the feasibility of this compound as an eco‐friendly method of masculinization of tilapia and can be tried in commercial aquaculture practice.

Enhancing replacement of fishmeal with corn protein concentrate by blending with soy protein concentrate and supplementing attractants in the diets of red hybrid tilapia

The objective of this study was to investigate the potential of enhancing the dietary substitution of fishmeal (FM) with corn protein concentrate (CPC) in the diets of red hybrid tilapia, Oreochromis sp., by blending CPC with soy protein concentrate (SPC) and adding betaine-HCl and dried basil leaves (DBL; feeding attractants). Seven isonitrogenous diets [FM100-CPC0-SPC0 (control); FM25-CPC75-SPC0 (75% of FM replaced by CPC); FM25-CPC50-SPC25 (50% and 25% of FM replaced by CPC and SPC, respectively); FM25-CPC50-SPC25B (with 0.5% betaine and 2% DBL); FM0-CPC100-SPC0 (100% diet protein from CPC); FM0-CPC75-SPC25 (75% and 25% of FM replaced by CPC and SPC, respectively) and FM0-CPC75-SPC25B (with 0.5% betaine and 2% DBL)] were formulated. Triplicate groups of tilapia fingerlings (average initial weight, 7.31 ± 0.03 g) were fed one of the diets for 56 days. The effects of high dietary levels of plant protein concentrate (PPC) on growth, nutrient utilization, body composition, body colouration and gut histology of tilapia were investigated. High levels of dietary CPC significantly (p < 0.05) reduced fish growth and feed intake. Blending CPC with SPC restored the growth performance of tilapia at the 75% PPC inclusion level. The addition of palatability enhancers further improved the growth of tilapia fed high PPC-based diets.

Comparing Transcriptomes Reveals Key Metabolic Mechanisms in Superior Growth Performance Nile Tilapia (Oreochromis niloticus).

Metabolic capacity is intrinsic to growth performance. To investigate superior growth performance in Nile tilapia, three full-sib families were bred and compared at the biochemical and transcriptome levels to determine metabolic mechanisms involved in significant growth differences between individuals under the same culture environment and feeding regime. Biochemical analysis showed that individuals in the higher growth group had significantly higher total protein, total triglyceride, total cholesterol, and high- and low-density lipoproteins, but significantly lower glucose, as compared with individuals in the lower growth group. Comparative transcriptome analysis showed 536 differentially expressed genes (DEGs) were upregulated, and 622 DEGs were downregulated. These genes were significantly enriched in three key pathways: the tricarboxylic acid cycle (TCA cycle), fatty acid biosynthesis and metabolism, and cholesterol biosynthesis and metabolism. Conjoint analysis of these key pathways and the biochemical parameters suggests that Nile tilapia with superior growth performance have higher ability to consume energy substrates (e.g., glucose), as well as higher ability to biosynthesize fatty acids and cholesterol. Additionally, the fatty acids biosynthesized by the superior growth performance individuals were less active in the catabolic pathway overall, but were more active in the anabolic pathway, and might be used for triglyceride biosynthesis to store excess energy in the form of fat. Furthermore, the tilapia with superior growth performance had lower ability to convert cholesterol into bile acids, but higher ability to convert it into sterols. We discuss the molecular mechanisms of the three key metabolic pathways, map the pathways, and note key factors that may impact the growth of Nile tilapia. The results provide an important guide for the artificial selection and quality enhancement of superior growth performance in tilapia.

Exploring the impacts of different fasting and refeeding regimes on Nile tilapia (Oreochromis niloticus L.): growth performance, histopathological study, and expression levels of some muscle growth-related genes

The current study investigated how different fasting and refeeding regimes would impact Nile tilapia growth performance, histopathological examination, and gene expression of myostatin, myogenin, GH, IGF-1, and NPYa. Nile tilapia fish (n = 120) were randomly allocated into four groups, including the control group fed on a basal diet for 6 weeks (F6), group A starved for 1 week and then refed for 5 weeks (S1F5), group B starved for 2 weeks and then refed for 4 weeks (S2F4), while group C starved for 4 weeks and then refed for 2 weeks (S4F2). Fasting provoked a decrease in body weight coincided with more extended starvation periods. Also, it induced muscle and liver histological alterations; the severity was correlated with the length of fasting periods. Gene expression levels of GH, MSTN, MYOG, and NPYa were significantly increased, while IGF1 was markedly depressed in fasted fish compared to the control group. Interestingly, refeeding after well-planned short fasting period (S1F5) modulated the histopathological alterations. To some extent, these changes were restored after refeeding. Restored IGF-I and opposing fasting expression profiles of the genes mentioned above thus recovered weights almost like the control group and achieved satisfactory growth compensation. Conversely, refeeding following more extended fasting periods failed to restore body weight. In conclusion, refeeding after fasting can induce a compensatory response. Still, the restoration capacity is dependent on the length of fasting and refeeding periods through exhibiting differential morphological structure and expressions pattern for muscle and growth-related genes.Graphical abstract

The effect of enzymatic Sargassum extract on feed consumption, feed utlitization efficiency, and growth rate of Nile tilapia (Oreochromis niloticus)

Tilapia have high resistance to various diseases, tolerance to low and high temperatures, efficiency in feed and fast growth, recently growing in saline water with salinity up to 20 ppt. The addition of Sargassum extract into the feed is an alternative to maintain water quality and digestibility of feed in the fish body. Sargassum sp, has a fairly complete nutritional content, it can certainly have a growth effect when added to fish feed, according to previous research. The nutritional content of Sargassum sp. including crude protein content 5.19%, ash content 36.93%, fat 1.63%. Sargassum sp. has a protein content of 7.94%, fat 0.72%, ash content 35.84%, crude fiber 4.93%, and carbohydrates 50.57%. Based on the background, it is necessary to do research on the addition of the enzymatic extract of Sargassum sp. such as neutrase and viscozyme into feed on feed conversion and growth performance of tilapia (Oreochromis niloticus).Sargassum collected from Pantai Karapyak, Pangandaran, West Java, Indonesia. Material and methods that used in research ranging from preparation of Sargassum extract, preparation of experimental animal, and experimental design. The utilization of Sargassum extract were effective to increase Feed Consumption (FC), Feed Utilization Efficiency (FE), and Absolute Growth Performance (AG) with the result of significant difference (p

Role of synbiotics (Lactobacillus acidophilus and prebiotic mixtures) to improve growth performance, feed utilization, biochemical and histological parameters of red tilapia (Oreochromis sp.)

Role of synbiotics (Lactobacillus acidophilus and prebiotic mixtures) to improve growth performance, feed utilization, biochemical and histological parameters of red tilapia (Oreochromis sp.)

Effects of Diet Supplemented with Morinda citrifolia Fermented Extract on the Growth Performance and Feed Conversion Ratio of Oreochromis niloticus

The use of additives in feeds to promote the growth of farmed fish has been rapidly expanding; among these are supplements derived from indigenous plants. Here, we analyzed the effects of satiation feeding of diet supplemented with noni (Morinda citrifolia) fermented extract on the feeding rate, growth performance and feed conversion ratio of Tilapia, Oreochromis niloticus. Fish with an initial average weight of 2.83 ± 0.01 g were fed with diets supplemented with noni fermented extract at 0 (control), 100-, 200- and 300-ml kg-1 for 12 weeks. Subsequent results showed that growth rate was correlated with or dependent on the concentration of noni fermented extract in the diet. The best result for growth performance, such as weight gain, average daily growth rate and specific growth rate, was found in a fish-fed diet supplemented with noni fermented extract at 200 ml kg-1. However, the feed conversion ratio (FCR) is still higher than the control. The high FCR compared to control may be due to the anthraquinone in noni fermented extract, which decreases nutrient absorption. Fish fed with a 300 ml kg-1 noni fermented extract supplemented diet was the lowest growth performance and highest in FCR, suggesting that concentrations over 200 ml kg-1 might be detrimental to fish. Taken together, noni fermented extract can be a natural source of feed supplement to improve fish growth performance and may act as an appetite stimulant. However, due to its laxative effect, noni fermented extract supplementation should be given at appropriate levels and effective feeding management.

Effect of polysaccharides derived from brown macroalgae Sargassum dentifolium on growth performance, serum biochemical, digestive histology and enzyme activity of hybrid red tilapia

The present trial conducted to examine the impact of dietary red seaweeds, Sargassum dentifolium polysaccharides supplementation on growth induces, hematological and histological indicators of the hybrid red tilapia Oreochromis mossambicus × Oreochromis niloticus fingerlings. A total of 240 hybrid red tilapia fingerlings with an average body weight of 7.50 ± 0.01 g were divided into four experimental treatments (three replicates each). Four identical isonitrogenous isoenergetic diets except the variation of polysaccharide (SP) levels were formulated. The basal experimental diet (control diet) had no seaweed polysaccharide added (SP0). Diets 2–4 (SP1; SP2 and SP3) was formulated to contained seaweed polysaccharide at levels of 10, 20, and 30 g/kg diet, respectively. Growth performance and feed utilization efficiency of hybrid Red tilapia were significantly (P ≤ 0.05) higher in all treatments receiving SP supplemented-diets than the control diet. The red blood cells (RBCs), hemoglobin (Hb) and hematocrit (Hct, %) values differed significantly (P ≤ 0.05) between the control and fish fed various SP supplemented diets. Considering the dietary SP supplementation, a clear higher trend values of RBC was observed with increasing dietary SP inclusion. Lipase activity recorded the highest values with the fish fed diet supplemented with SP at a level of 20 g/kg-1 associated with the lower significant values amylase activity compared to other treatments. Dietary SP supplementation had no effect on total plasma protein, albumin and globulin levels. Fish fed SP2 diet had an increase in GOT, triglycerides. Fish fed SP3 recorded the lowest value of total cholesterol and LDL when compared to other diets. No abnormal or histological changes were detected in sections of liver, stomach and intestine of red tilapia fed different dietary supplemented with SP levels. The findings of current trial revealed that hybrid Red tilapia fed diets containing red seaweeds, polysaccharides for 12 weeks had enhanced performance, feed conversion ratio and hematological indices.

Effects of different types of non-starch polysaccharides on growth, digestive enzyme activity, intestinal barrier function and antioxidant activity of tilapia (Oreochromis niloticus)

The effects of different types of non-starch polysaccharides (NSPs) on growth performance, antioxidant activity and intestinal mucosal barrier function of tilapia (Oreochromis niloticus) were evaluated through a 10-week feeding trial. Eleven isonitrogenous (32% crude protein) and isoenergetic (20 MJ/kg) diets were prepared without (control) or with 3.96% arabinoxylan, 0.92% β-glucan, 1.06% mannan, 7.92% pectin, 6.60% cellulose, 1.06% lignin, 1.51% alduronic acid, 13.86% soluble NSPs (sNSP, 3.96% arabinoxylan + 0.92% β-glucan + 1.06% mannan + 7.92% pectin), 9.17% insoluble NSPs (iNSP, 6.60% cellulose + 1.06% lignin + 1.51% alduronic acid) and 23.03% NSP (13.86% sNSP + 9.17% iNSP), respectively. Dietary inclusion of β-glucan or pectin significantly increased weight gain rate (WGR), daily growth coefficient (DGC), hepatic lactase and plasma catalase (CAT) activities. Dietary inclusion of arabinoxylan or mannan significantly decreased hepatic lactase activity,WGR and DGC, significantly increased diamine oxidase (DAO) activity. Dietary inclusion of iNSP or NSP significantly increased WGR, DGC, feed intake, feeding rate, intestinal lipase and lactase activities, hepatic amylase and lactase activities, plasma superoxide dismutase (SOD) and CAT activities, and hepatic SOD activity, significantly reduced pepsin activity and hepatic malondialdehyde (MDA) content. Furthermore, dietary inclusion of sNSP significantly increased feed coefficient ratio, feed intake, pepsin and hepatic trypsin activities, hepatic MDA and plasma DAO contents, and significantly decreased protein efficiency, plasma CAT and hepatic peroxidase activity. These results showed that dietary inclusion of arabinoxylan, mannan or sNSP negatively affected the growth and health of tilapia, while dietary inclusion of β-glucan, pectin or iNSP shown a positive effect; dietary inclusion of iNSP can ameliorate the negative effects produced by sNSP.

Modulatory effects of dietary cinnamon (Cinnamomum zeylanicum) against waterborne lead toxicity in Nile tilapia fingerlings: Growth performance, haemato-biochemical, innate immunity, and hepatic antioxidant indices

This study investigated the protective effect of dietary cinnamon (Cinnamomum zeylanicum) powder (CzP) on the growth performance, haemato-biochemical, innate immunity, and hepatic antioxidant indices of tilapia (Oreochromis niloticus) fingerlings against the toxic effect of prolonged lead (Pb) exposure. Fish (22.6–25.3 g) were fed on diets supplied with two CzP levels (0.0 (control) and 10 g/kg diet) up to satiety for 60 days. At each CzP level, fish were exposed to 0.0 and 7.94 mg Pb/L in five replicates. At the end of this trial, Pb residues in the whole-fish body as well as haemato-biochemical, antioxidant, and immune indices were determined. The waterborne Pb adversely affected the growth performance, white blood cells and red blood cells counts, hematocrit, and hemoglobin levels. Blood cortisol, glucose, total cholesterol, serum alanine and aspartate aminotransferases and lactate dehydrogenase values were significantly higher; meanwhile, total lipids, total protein, albumin, and globulin as well as alkaline phosphatase were significantly lower in Pb-exposed fish. Hepatic oxidative stress biomarkers (malondialdehyde, superoxide dismutase, catalase, and total antioxidant activity) and serum immune indices (respiratory burst activity, serum lysozyme activity, and total immunoglobulins) were progressively suppressed by Pb exposure. On the other hand, the dietary supplementation of cinnamon powder alone significantly enhanced the growth, hemato-biochemical, antioxidant, and immune indices of Nile tilapia. Additionally, dietary CzP significantly mitigated Pb-induced effects in regard to the above-mentioned variables. Exposing Nile tilapia to Pb toxicity induced significant Pb accumulations in the whole-fish body; meanwhile the dietary CzP effectively reduced the Pb accumulation in the body of Pb-exposed fish. Thus, the dietary CzP had several encouraging effects on growth, antioxidant, and immune indices of Nile tilapia. Feeding the Pb-exposed fish with CzP effectively reduced the Pb accumulation in the fish body and offered direct protection against Pb-induced oxidative stress. The findings of the present study suggest that dietary cinnamon can be used as an immune-stimulant for mitigating the effects of heavy metals toxicity in Nile tilapia aquaculture.

Growth Performance of Tilapia Fed with Feed Containing Moringa Leaf Meal and Shrimp Meal

The research objective of this study was to determine the impact of feed enrichment using Moringa leaf meal and shrimp meal on the growth performance of Tilapia. The initial weight of experimental fish was 6.10 ± 0.55 g/ head. The treatments given were Treatment A (feed without Moringa leaf meal and shrimp meal), Treatment B (commercial feed + 20% shrimp flour), Treatment C (commercial feed + 10% Moringa leaf meal + 20% shrimp meal), and Treatment D (commercial feed + 20% Moringa leaf meal + 20% shrimp meal). In total, there were 4 treatments with 3 replications each. Fish rearing lasted for 40 days. The results showed that the treatments had no effect on amount of feed consumption, protein efficiency ratio, specific growth rate, feed efficiency, survival rate, coefficient of variation and hepatosomatic index (p&gt;0,05), but had an effect on the amount of protein consumption and body protein (p&lt;0, 05). In conclusion, the enrichment of feed containing Moringa leaf meal and shrimp meal had no effect on the growth performance of Tilapia.

Evaluation of feeding response and growth performance of tilapia (Orechromis niloticus) that conditioned with color-assigned LED that associated with feeding and stressor

Conditioning can be applied as a management tool to increase the efficiency of aquaculture production by training the fish to gather into a designated site for feeding or harvesting purposes and reducing stress from handling or other external stressors that can be found in the ambient environment. While the use of conditioning in aquaculture can be beneficial, there is limited information on the application of this technology in tilapia. Thus, this research was conducted to evaluate the use of different color lights as positive and negative conditioning on feeding response and growth performance of tilapia. Treatment that used in this research is using random light at a random location that was independent of the random feeding location (P1); using blue color at a random location adjacent to the feeding location (P2); using similar treatment with P2 but with the incorporation of conditioning in the form of stress; and control treatment without conditioning. As the result, there is no significant difference among treatments in growth performance and feed conversion, and the application of these conditionings affects tilapia’s feeding response. Treatment P2 produces an improved feeding response compared to other treatments and incorporation of stress into treatment such as in treatment P3 may curb this improvement.

Probiotic effect of Bacillus spp. isolated from African nightcrawler (Eudrilus eugeniae) on the performance of Nile Tilapia (Oreochromis niloticus L.).

This study evaluated the effects of the probiotic Bacillus spp. isolated from African nightcrawler (Eudrilus eugeniae) on the growth and survival performances of Nile tilapia (Oreochromis niloticus). A total of 400 Nile tilapia fingerlings (1.76 ± 0.07g) were equally and randomly distributed into 20 glass aquaria and divided into five experimental groups with four replicates. Each experimental group was fed with a commercial diet (control) supplemented (at 108CFU·g-1) with one of the four Bacillus spp. (ANSCI9, BFAR9, RM3, and RM10) at five percent of their body weight. After 30days of feeding, the surviving fish were challenged with Aeromonas hydrophila to observe their survival. The treatment groups supplemented with BFAR9 (2.73 ± 0.26g) and RM10 (3.15 ± 0.30g) showed significantly higher (P < 0.05) absolute growth than the control (2.20 ± 0.16g) group. Furthermore, those given with RM10 had better (P < 0.05) specific growth rate (SGR) (1.60 ± 0.10%·day-1) relative growth rate (RGR) (181.39 ± 18.16%) and feed conversion ratio (FCR) (1.99 ± 0.13) compared to the control group (SGR = 1.29 ± 0.07%·day-1; RGR = 129.84 ± 9.77%; FCR = 2.60 ± 0.16). The challenge test revealed that all Bacillus spp.-treated groups showed significantly higher (P < 0.05) survival rates (ANSCI9 = 82.5 ± 8.16%; BFAR9 = 80.0 ± 10.00%; RM3 = 77.5 ± 20.82%; RM10 = 85.0 ± 10.00%) than the control group (55.00 ± 19.15%), with the highest relative level of protection recorded for RM10 (66.67%). These results revealed that the probiotic Bacillus spp. isolated from E. eugeniae improved the growth, feed utilization, waste excretion, and the disease resistance of Nile tilapia.

Comparison Of Growth Of Organic Tilapia From Selective Breeding Program, Fed With Organic Pellet Feed and Duckweed Under The Biofloc Farming System

This study was conducted to compare the growth performance of organic tilapia from the selective breeding program, fed with organic pellet feed and duckweed under the biofloc farming system. A total of 100 full sib families with stocking weight 20.2 (7.54) g was randomly separated from each family and divided into two groups. Each group was stocked in four separates 2m by 2m by 1m cages, the cages were hanged in 64 m3 P.E. tank under biofloc system. The first group was fed with organic pellets (34% protein feed), for 4 replicates in the same tank. Another group was fed with duckweed, for 4 replicates in another same tank. After two months of rearing, the growths of organic tilapia from the selective breeding program fed with organic pellet feed and duckweed under the biofloc farming system were not significantly different (p>0.05) for both total weight and length. The total weight and length of organic tilapia fed with duckweed and organic pellet feed were 29.47 (23.55) and 29.09 (23.67) g, respectively. The main finding of the present study is that the duckweed can be used in a selective breeding program of Nile tilapia without altering the relative performance of the families. This finding is of benefit since it justifies the current trends of organic tilapia production.

The effects of field cricket (Gryllus bimaculatus) meal substitution on growth performance and feed utilization of hybrid red tilapia (Oreochromis spp.)

The rising cost and uncertain availability of fish meal supply have forced fish feed manufacturers to find inexpensive, abundant and readily available alternative protein sources as substitutes. This study aimed to investigate the potential of using field cricket meal (CM) from Gryllus bimaculatus as a source of main protein in fish feed for hybrid red tilapia (Oreochromis spp.) The experimental diets were CM0, CM25, CM50, CM75 and CM100. Proximate analysis and amino acid analysis were carried out to analyze nutrient content in each treatment diet. Hybrid red tilapia juvenile were uniformly distributed at a stocking density of 25 juveniles per m3 in triplicate for each experimental tank. Fish were fed twice daily at the rate of 3% of total body weight for 98 days and weighted fortnightly. The result shows that cricket could be used to replace fish meal up to 50% without causing any significant effect on growth performance and feed utilization. Even though CM100 and CM75 shows significantly lower growth performance, the whole-body composition analysis of tilapia fed with CM100 had significantly increased percentage of protein and lipid compared to the CM0. This indicates that cricket meal has a great potential to be used as an alternative protein source to substitute fish meal in fish feed.

Effects of probiotic (Sanolife PRO‐W) application on benthic meiofauna and Nile tilapia growth performance in earthen ponds

The interaction between fish and probiotics has been widely studied, whereas the interactions among meiofauna, probiotics and fish have yet to be explored. In September 2019–July 2020, the effects of a probiotic (Sanolife PRO-W) on meiofaunal abundance, biomass and diversity, and the impact of these effects on Nile tilapia were studied. Two treatments were applied in earthen ponds: control (C) and probiotic-treated (T). In spring–summer, a net was used to separate each pond into two areas with fish presence (O) or fish absence (I). Samples were randomly collected bimonthly and monthly from ponds in autumn–winter and spring–summer, respectively. Cladocera, Rotifera, Nematoda and Oligochaeta were dominant in the probiotic-treated pond. The abundance, biomass and diversity of meiofauna did not differ between the ponds in autumn–winter. However, in spring–summer, meiofauna abundance differed in the following treatment pairs: CO vs. TO, CI vs. TI, CI vs. CO and TI vs. TO. Furthermore, biomass differed in CO vs. TO and CI vs. TI, whereas diversity differed in CI vs. TI and TI vs. TO. These results improve our understanding of positive fish–probiotic interactions; however, additional research is required to explore the relationships identified in these preliminary findings.

Dietary magnolol inclusion improves the antioxidant and immune responses, and resistance to Aeromonas hydrophila in genetically improved farmed tilapia (Oreochromis niloticus)

A 10-week feeding trial was conducted to evaluate the effects of dietary magnolol inclusion on the growth rate, antioxidant and immune responses of genetically improved farmed tilapia Oreochromis niloticus. Four experimental diets were formulated with 0%, 0.02%, 0.04% and 0.08% magnolol, respectively. Dietary 0.02–0.08% magnolol inclusion did not affect the growth rate and feed utilization of tilapia. However, dietary 0.02–0.08% magnolol inclusion increased the plasma catalase, the intestinal alkaline phosphatase (ALP), and the hepatic glutathione reductase (GR) and catalase activities; but reduced the hepatic malondialdehyde (MDA) content. Further, supplementation with 0.04–0.08% magnolol increased the plasma superoxide dismutase (SOD), peroxidase, ALP and total antioxidant capacity (TAC), the intestinal GR, catalase, peroxidase and TAC, and the hepatic SOD and TAC activities; but decreased the plasma MDA, the intestinal MDA and reactive oxygen species contents. Dietary 0.02–0.04% magnolol inclusion increased the plasma complement 3 content, whereas the plasma immunoglobulin M, complement 4 contents and lysozyme activity were increased by dietary 0.04–0.08% magnolol inclusion. The phagocytic activity of head kidney macrophages was increased by the inclusion of 0.04% magnolol. Additionally, supplementation with 0.02–0.08% magnolol increased the relative percentage survival of tilapia after infection with Aeromonas hydrophila. These results indicated that 0.04% magnolol inclusion improved the antioxidant and immune responses without compromising growth performance of tilapia, suggesting that magnolol could be used as an antioxidant and immunostimulant in aquafeed.

A Comparison of the Beneficial Effects of Inorganic, Organic, and Elemental Nano-selenium on Nile Tilapia: Growth, Immunity, Oxidative Status, Gut Morphology, and Immune Gene Expression.

This study investigates the effects of different sources of selenium (inorganic (SSE), organic (OSE), and elemental nano-selenium (NSE)) on the performance of Nile tilapia (Oreochromis niloticus). In total, 204 Nile tilapia fingerlings were randomly divided into 4 equal groups fed 1 of 4 diets: a control (adding no selenium) and 3 diets as selenium sources (1mg/kg diet), After a 65-day feeding trial, the growth performance parameters of Nile tilapia were significantly enhanced by dietary selenium supplementation (P < 0.05), with the highest values recorded in the OSE- and NSE-supplemented groups. The selenium-supplemented groups had the highest packed-cell volume, hemoglobin, and red blood cell levels, with the highest values seen in the NSE-supplemented group (P < 0.05). Innate immune-related enzymes and immunoglobulin levels were significantly enhanced with selenium supplementation (P < 0.05); the NSE group demonstrated the highest significant levels of these enzyme activities (P < 0.05). In all selenium-supplemented groups, malondialdehyde levels were significantly and equally reduced (P < 0.05) compared with levels in the control. Bactericidal activity was only enhanced in the NSE group (P < 0.05) compared with other treatments. The expression of TNF-α and IL-Iβ genes was significantly upregulated in selenium-supplemented groups, with the highest expression in the OSE and NSE groups (P < 0.05). These findings support the importance of incorporating selenium in the diet of Nile tilapia. Furthermore, elementary nano-selenium is more effective than inorganic or organic selenium supplementation at improving Nile tilapia growth performance and overall health.

Effect of Supplementation of Dried Bioflocs Produced by Freeze-Drying and Oven-Drying Methods on Water Quality, Growth Performance and Proximate Composition of Red Hybrid Tilapia

Supplementation of dried bioflocs for red hybrid tilapia (Oreochromis sp.) was examined during 57 days of feeding trials. Five experimental treatments; T1 (the control; without bioflocs), T2 (4% freeze-dried bioflocs), T3 (16% freeze-dried bioflocs), T4 (4% oven-dried bioflocs), and T5 (16% oven-dried bioflocs) were prepared to examine the water quality, growth performance and body composition of red hybrid tilapia. T2 and T4 treatments resulted in a higher growth rate and survival similar to the control, while T3 and T5 treatments showed the lowest values of growth performance among all treatments. T1 treatment showed the best quality of culture water followed by T2 and T4 treatments, while T3 treatment resulted in poor water quality followed by T5 treatment. Based on these results, the ratios of bioflocs (4% and 16%) had more effect on fish growth and water quality than the drying methods (freeze-drying and oven-drying). The ratio of 4% freeze-dried or oven-dried bioflocs provided higher growth rates and better water quality parameters similar to the control, while the ratio of 16% showed the worst growth performance and water quality in the present study. In addition, body compositions of tilapia fed 4% dried bioflocs showed better nutritional value than tilapia fed 16% dried bioflocs. Protein and energy levels showed an increasing trend with decreasing supplement levels of bioflocs. Moisture content was significantly higher when supplementation of 16% bioflocs was used. Overall, supplementation of 4% freeze-dried or oven-dried bioflocs can be successively included in red hybrid tilapia diets without any effects on growth or body composition and can result in a good quality of culture water for red hybrid tilapia.

Growth performance of Tilapia (Oreochromis niloticus) cultivated in water from ex-sand pit lakes by phytoremediation treatments

Utilization of ex-sand pit lakes for aquaculture is difficult due to low water quality and high concentrations of iron (Fe). Phytoremediation using aquatic plants has been proven to be effective in reducing Fe in waters. This study aims to determine the growth, feed conversion efficiency and survival rate of tilapia (Oreochromis niloticus) cultured with ex-sand mining water media with phytoremediation treatment. Phytoremediation treatment was carried out by Eichhornnia crassipes, Azolla pinnata, and Salvinia molesta. Fish culture experiments were carried out in plastic tarpaulin tanks for 40 days, with ad satiation feeding, three times a day using the commercial feed. The results showed that phytoremediation with aquatic plants had succeeded in reducing Fe to a level suitable for fish culture. Fish culture experiments showed an absolute length growth rate of 0.09-0.18 cm/day and an absolute weight growth rate of 0.11-0.16 g/day. The feed conversion ratio was 1.18-1.40 and the survival rate was 98.04-99.08%. The survival rate of tilapia is high, the feed conversion ratio is medium and growth is low. The high environmental temperature and the decrease in water quality due to the absence of water changes and aeration are suspected of causing the low growth of fish. Therefore, further research with water change and aeration experiments and the use of other species of fish is needed to follow up the results of this study.