Growth Performance Of Fish Research Articles

Effects of Stocking Density on the Growth Performance, Physiological Parameters and Antioxidant Status of Juvenile Common Carp (Cyprinus carpio L.) Reared in the Cage system

Stocking density is one of the most important factors influencing growth performance, health status and welfare of fish in aquaculture. This research was carried out to investigate the effect of different stocking densities on growth performance, feed utilization, survival rate, haematology, serum biochemistry and serum antioxidants enzyme responses in common carp juveniles (Cyprinus carpio L.) reared in outdoor cage culture. The fish were randomly stocked in four density groups; 7F fish/0.2m3 (Control group), 14F fish/0.2m3, 21F fish/0.2m3 and 28F fish/0.2m3 in 12 cylindrical cages (0.2m3) in concrete pond, with three cages in each density for 84 days. The results of the 14f density group significantly improved the FW, WG, SGR, FCR, FCE, PER, FI, PI, WBC, RBC, Hct, GSH and SOD activities. The 21F and 28F had significant impacts on FW, WG, SGR, FCR, FCE, PER, FI, PI, glucose, cortisol, ALT, AST, ALP, TG, MDA and GSH increased significantly with increasing stocking density. In contrast, the survival rate, TP, TG, HDL, GPx and SOD activities were significantly decreased. In general, the results demonstrated that the best stocking density is 14F fish/0.2m3 which provided a better growth performance and health status of C. carpio cultured in the cage in the concrete pond.

Fermentation in aquafeed processing: Achieving sustainability in feeds for global aquaculture production

AbstractImproving feed suitability and bolstering the global upsurge in fish production is a strategic challenge for aquaculture. The utilization of plant and animal derived ingredients in aquafeed for achieving sustainable in finfish aquaculture is affected by various factors, including the presence of antinutritional factors, lowered nutrient bioavailability, indigestible particles and microbial contaminants. Applying fermentation to overcome these problems in aquafeed ingredients has received considerable attention in recent years as fermentation provides health‐promoting probiotic benefits to host organisms. Fermentation has also been shown in many studies to improve nutrient availability and bioavailability of feed, increased palatability and digestibility and eliminate anti‐nutritional compounds in dietary feed ingredients, making them more easily digestible which eventually improve growth and health performance of fish. Therefore, it is imperative to accelerate the use of fermented feedstuffs as aquafeed if sustainable aquaculture is to be achieved. This review reported the various methods of fermentation, characteristics of fermented feed ingredients, factors that are considered during fermentation and overall nutritional quality of fermented feed ingredients for aquaculture production. The role of fermented feed ingredients for various farmed species in terms of growth, feed utilization, gut microbiota composition, immunity and disease resistance in fish is thoroughly discussed. The possible drawbacks associated with the fermentation process are also discussed in the article.

Assessment of Full-Fat Tenebrio molitor as Feed Ingredient for Solea senegalensis: Effects on Growth Performance and Lipid Profile.

Tenebrio molitor (TM) is considered as one of the most promising protein sources for replacing fish meal in aquafeeds, among other things because it is rich in protein, a good source of micronutrients and has a low carbon footprint and land use. However, the main drawback of TM is its fatty acid profile, in particular its low content of n-3 PUFA. This study evaluates the effects of partially replacing plant or marine-derived with full-fat TM meal at two different levels on growth performance and lipid profiles of Senegalese sole (Solea senegalensis). For this purpose, a control diet (CTRL) and four experimental isoproteic (53%) and isolipidic (16%) diets were formulated containing 5 and 10% TM meal replacing mostly fish meal (FM5 and FM10), or 10 and 15% TM meal replacing mostly plant meal (PP10 and PP15). Fish (215 g) were fed at 1% of their body weight for 98 days. The final body weight of fish fed the experimental diets containing TM meal was not different from that of fish fed the CTRL diet (289 g). However, the inclusion of TM meal resulted in a gradual improvement in growth rate and feed efficiency in both cases (replacement of fish or plant meals), and significant differences in specific growth rate (SGR) were observed between fish fed the CTRL diet (SGR = 0.30% day-1) and those fed diets with the highest TM meal content (PP15; SGR = 0.35% day-1). The experimental groups did not show any differences in the protein content of the muscle (19.6% w/w). However, significant differences were observed in the total lipid content of the muscle, with the FM10, PP10, and PP15 groups having the lowest muscle lipid contents (2.2% ww). These fish also showed the lowest neutral lipid content in muscle (6.6% dw), but no differences were observed in the total phospholipid content (2.6% dw). Regarding the fatty acid profile, fish fed FM10, PP10 and PP15 had lower levels of linoleic acid (18:2n-6) and higher levels of oleic acid (18:1n-9) in liver and muscle compared to fish fed CTRL. However, no differences were found between fish fed CTRL and TM-based diets for docosahexaenoic acid (22:6n-3) and total n-3 PUFA in liver and muscle. In conclusion, our study demonstrated that full-fat TM inclusion up to 15% in S. senegalensis diets had no negative effects or even some positive effects on fish survival, growth performance, nutrient utilization and flesh quality.

Effectiveness of Different Tyroxine Hormone Dosages on The Growth Performance And Violability of Depik Fish (Rasbora tawarensis)

Depik fish is a fish which is one of the endemic species in Lake Laut Tawar, Central Aceh Regency. Typical fish of the Gayo community which is currently being developed for domestication. However, from the results of several studies, the growth of depik fish is relatively slow, so it needs to be increased. One way to accelerate the growth of depik fish is by hormonal induction, through immersion in the hormone thyroxine with different doses. The aim of this research is to evaluate the growth performance and survival of depik fish soaked in thyroxine hormone with different doses of thyroxine hormone. This research was carried out at the Lukup Badak Fish Seed Center (BBI), Central Aceh using a completely randomized design (CRD) experimental method with four treatments and three repetitions. The treatments in this research were different durations of immersion in the thyroxine hormone, namely: no dose (P0), 0.05 mg/ liter (P1), 0.1 mg/ liter (P2), and 0.15 mg/ liter (P3). Meanwhile, the duration of the thyroxine hormone soaking used is 24 hours. Rearing of fish seeds is carried out using an Aquarium measuring 30 cm long, 20 cm wide and 25 cm high according to the treatment, for 28 days with a stocking density of 20 fish/container. This study concluded that different doses of the thyroxine hormone in Depik fish fry gave the highest growth in the treatment dose of 0.15 mg/liter, while the lowest growth was in the control treatment (no dose).

Microalgae as fishmeal alternatives in aquaculture: current status, existing problems, and possible solutions.

Fishmeal is an indispensable ingredient for most aquatic animals. However, the finite supply and escalating price of fishmeal seriously limit its use in aquaculture. Thus the development of new, sustainable protein ingredients has been a research focus. Microalgae are potential fishmeal alternatives owing to their high protein content and balanced amino acid profile. Studies suggest that suitable replacement of fishmeal with microalgae is beneficial for fish growth performance, but excessive replacement would induce poor growth and feed utilization. Therefore, this paper aims to review research on the maximum substitutional level of fishmeal by microalgae and propose the main issues and possible solutions for fishmeal replacement by microalgae. The maximum replacement level is affected by microalgal species, fish feeding habits, quality of fishmeal and microalgal meals, and supplemental levels of fishmeal in the control group. Microalgae could generally replace 100%, 95%, 95%, 64.1%, 25.6%, and 18.6% fishmeal protein in diets of carp, shrimp, catfish, tilapia, marine fish, and salmon and trout, respectively. The main issues with fishmeal replacement using microalgae include low production and high production cost, poor digestibility, and anti-nutritional factors. Possible solutions to these problems are recommended in this paper. Overall, microalgae are promising fishmeal alternatives in aquaculture.

Pengaruh Eubiotik sebagai Feed Additive untuk Meningkatkan Kinerja Pertumbuhan Ikan Gabus

Purpose: These studies were carried out so that the snakehead fish cultivation process can be optimal. Method: The study used a completely randomized design (CRD) with four treatments and three replicates for each treatment. Result: The treatments used in this study were K: Feed without a mixture of Eubiotics (control), A: Feed mixed with Eubiotics in the amount of 5 ml/100gr of feed, B: Feed mixed with Eubiotics in the amount of 10 ml/100gr of feed, C: Feed mixed with Eubiotics in the amount of 15 ml/ 100gr feed. Limitation: One of the feed additives that can be used to help increase the absorption of fish feed nutrients so that fish growth performance can be better is Eubiotics Contribution: One effort that can be done to improve feed digestibility is the addition of feed additives. Giving feed additives is also able to increase the absorption of nutrients in fish feed. non-nutritive substances that have many benefits, especially by increasing the effectiveness of the feed, namely additives.

Role of Dietary Microalgae on Fish Health and Fillet Quality: Recent Insights and Future Prospects

An increase in the consumption of food fish, combined with a decrease in the harvest of fish, is driving the aquaculture industry at a fast pace. In parallel with the growth in the aquaculture sector and resulting stresses, the prevalence of diseases in farmed fish can increase. Although effective administration and prophylaxis are the main factors safeguarding fish species against diseases, recent approaches to mitigate the response caused by typical stressors include the uses of dietary additives. Microalgae are one of the main sources of nutrients, namely protein, lipids, vitamins, minerals, and pigments in aquatic animal diets. Numerous studies have proved the beneficial effects of microalgae on fish growth performance, feed utilization, disease resistance, and immunological and antioxidant activities. On the other hand, the administration of different microalgae to fish feed can enhance the fillet quality from several aspects, leading to an overall improvement in fillet shelf-life. This review focuses on the evidence supporting the beneficial effects of various microalgae on biochemical and organoleptic aspects as well as the proximate composition of carcasses in fish species.

Effect of biofloc technology at varies biological factors on the growth performance and water quality in cultivation of red hybrid tilapia

Aquaculture is one of the important food-producing sectors. However, the effluent of the aquaculture system consists of pollutants such as nitrogenous compounds and the ample usage of water for traditional aquaculture systems. Therefore, biofloc technology was developed in the aquaculture industry in the 1980s to improve the water quality of the system and increase the fish production. The purpose of this experimental work is to investigate the effect of biological factors on the growth performance of fish and the water quality of the biofloc technology (BFT) aquaculture system for red hybrid tilapia cultivation. In this study, 3 biological factors such as the carbon-to-nitrogen ratio, stocking density and the feeding rate were studied under BFT. Parallel experiments in thirteen suspended growth tanks were carried out within (10:1-20:1) C/N ratio, (1%-5%) feeding rate and (20-80 fish m-3) stocking density for 10 weeks. Growth rate of fish and water quality data such as ammonia, nitrite and nitrate concentrations were collected weekly during the study. The results revealed that the 20:1 C/N ratio gave the best water quality. Feeding rate at 4% of body weight produced good growth performance of the tilapia species and the higher stocking densities lead to lower water quality and survival rate.

Analysis of biological factors on affecting the growth performance and water quality of biofloc aquaculture system for freshwater barramundi

Biofloc technology is used to improve water quality and fish growth performance of aquaculture. The purpose of this research is to analyse the biological factors on freshwater barramundi in biofloc aquaculture system. Three set of experiments with 3 biological factors were carried out for freshwater barramundi to analyse the water quality and to evaluate the cultivated fish growth performance under the application of biofloc technology for 10 weeks. The biological factors involved are stocking density, carbon-to-nitrogen ratio and feeding rate. The water quality parameters were monitored weekly while the growth indices will be determined at the end of the experiments. The results revealed that stocking density has insignificant effect on the water quality but essential affected the growth rate of the freshwater barramundi. The best growth rate is observed at lowest stocking studied (10 fish/m3). The biofloc technology aquaculture system with C:N ratio of 16:1 and lowest stocking density (10 fish/m3) produced the best water quality and growth performance. Meanwhile the compatible feeding rate for the juvenile freshwater barramundi was identified at rate of 1% of fish body weight with feeding frequency once or twice a day in order to control the water quality and produced good growth performance of the juvenile.

Effect of growth performance and survival of Oreochromis niloticus Nile tilapia fish under biofloc system

Effect of growth performance and survival of Oreochromis niloticus Nile tilapia fish under biofloc system

Effects of dietary β-glucans on the productive performance, blood parameters, and intestinal microbiota of angelfish (Pterophyllum scalare) juveniles.

Among the potential feed additives, β-glucans are known to positively affect the growth performance, blood parameters, and intestinal microbiota of fish, even the ornamental species. Therefore, the present study evaluated the effects of the dietary supplementation of different Saccharomyces cerevisiae β-glucans concentrations (0, 0.05, 0.1, and 0.2%) in juvenile angelfish (Pterophyllum scalare) over a 42-day period. Regarding growth performance, no effects were observed on most parameters. However, 0.2% β-glucans supplementation produced higher condition factor values, indicating a better nutritional status. Furthermore, β-glucans supplementation did not affect blood parameters. Regarding intestinal microbiota, β-glucans supplementation increased the abundance of the potentially beneficial bacterial genus Phascolarctobacterium. The high abundance of bacteria from the phylum Bacteroidetes, which can degrade β-glucans, may be attributed to the increased abundance of Phascolarctobacterium spp. In addition, 0.2% β-glucans supplementation produced more operational taxonomic units and higher Sobs (observed species richness), indicating effects on the overall bacterial community structure. These results demonstrate the potential application of β-glucans as a dietary supplement to improve the performance and modulate the intestinal microbiota of angelfish.

Could future ocean acidification be affecting the energy budgets of marine fish?

With the unprecedented environmental changes caused by climate change including ocean acidification, it has become crucial to understand the responses and adaptive capacity of fish to better predict directional changes in the ecological landscape of the future. We conducted a systematic literature review to examine if simulated ocean acidification (sOA) could influence growth and reproduction in fish within the dynamic energy budget theory framework. As such, we chose to examine metabolic rate, locomotion, food assimilation and growth in early life stages (i.e. larvae and juvenile) and adults. Our goal was to evaluate if acclimatization to sOA has any directional changes in these traits and to explore potential implications for energetic trade-offs in these for growth and reproduction. We found that sOA had negligible effects on energetic expenditure for maintenance and aerobic metabolism due to the robust physiological capacity regulating acid-base and ion perturbations but substantive effects on locomotion, food assimilation and growth. We demonstrated evidence that sOA significantly reduced growth performance of fish in early life stages, which may have resulted from reduced food intake and digestion efficiency. Also, our results showed that sOA may enhance reproduction with increased numbers of offspring although this may come at the cost of altered reproductive behaviours or offspring fitness. While these results indicate evidence for changes in energy budgets because of physiological acclimatization to sOA, the heterogeneity of results in the literature suggests that physiological and neural mechanisms need to be clearly elucidated in future studies. Lastly, most studies on sOA have been conducted on early life stages, which necessitates that more studies should be conducted on adults to understand reproductive success and thus better predict cohort and population dynamics under ongoing climate change.

Complete Replacement of Fish Meal with Potential Aquafeed Ingredients for Rainbow Trout in Iran

Iran, as one of the largest rainbow trout producers in the world, needs sustainable aquafeed resources to fulfill the requirements of this growing industry. Therefore, locally available canola meal, feather meal, blood meal and poultry by-product meal were evaluated on their suitability for feeding rainbow trout. Fish growth performance and apparent digestibility coefficients (ADCs) of nutrients were investigated for three casein-based fish meal-free diets, a practical feed including 10% spray-dried blood meal, 22% poultry by-product meal, 10% feather meal (GOLDMEHL®), 10% canola meal and 15.5% wheat flour in comparison to a commercial diet containing fish meal. The diets were allocated to aquaria in three replicates arranged in a random-block-design. Findings of the present study illustrated that growth performance remained unchanged (p>0.05) among fish fed fish meal-free diets and the commercial one. Formulating aquafeed using properly processed local feed ingredients such as poultry slaughterhouse by-products, canola meal, and crystalline amino acids can provide a sustainable solution to meet the feed requirements of the growing aquaculture industry on a regional scale. This research shows the potential for using locally available resources in aquafeed manufacturing.

The effects of diets containing rapeseed meal on Siberian sturgeon (Acipenser baerii) growth, muscle composition, and physiological performance

Sturgeon farming is a rapidly developing aquaculture sector which requires high-quality feeds. As an ingredient of animal feeds, fishmeal is often replaced with cheaper plant-based protein sources, such as rapeseed cake meal, a by-product of canola oil pressing. The aim of the present study is to evaluate the effects of diets containing various levels of rapeseed cake meal on the juvenile Siberian sturgeon (Acipenser baerii) growth, hematological and biochemical parameters, as well as muscle composition. An 8-week feeding trial was conducted on fish with average body weight of 216.2 ± 45.7 g. Fish were fed diets were 0%, 10%, 20%, and 30% of fish meal and soybean meal were replaced with rapeseed meal (groups A, B, C, and D, respectively). Additionally in E diet (30% rapeseed meal) effects of phytase addition RENOZYME® HiPhos 20000 in concentration 2000 IU was tested. During the experiment, no mortalities were observed in each of the studied groups. Similar values of morphometric and breeding parameters were observed in groups A, B, C, D and E. No hematological effects of rapeseed diets occurred, except for significantly lower erythroblast levels in groups B, C, D, and E compared to A. Group B showed a higher plasma glucose concentration compared to the other groups. ALT activity in groups D and E were lower than in groups A, B, and C. The muscles of individuals from group B showed the highest dry matter and fat content, while the highest protein content occurred in group C. Despite significant differences in the values of some parameters, the obtained results indicate that the replacement of 10–30% of fishmeal with rapeseed meal in the feed for the juvenile Siberian sturgeon did not compromise fish survivability, growth performance, health, or body composition, although phytase addition did not improve the effects of administering rapeseed-containing feed.

Effectiveness of endophytic bacteria for some medicinal plants as probiotics for Nile tilapia (Oreochromis niloticus)

The main objective of this research is to study the possibility of using endophytic bacteria isolated from some medicinal plants (onion, Allium cepa, brassicales, Salvadora persica, and fenugreek, Trigonella foenum-graecum) as probiotics for Nile tilapia (Oreochromis niloticus). Fish growth was evaluated using fish growth performance indices and approximate fish composition. Fish health was assessed by quantifying some biochemical compounds in fish serum, and at the end of the experiment, a challenge test was performed with Vibrio parahaemolyticus. The use of endophytic bacteria increased all indicators of growth performance compared to the control group. Endophytic bacteria of Fenugreek recorded higher growth performance than other plants. Moreover, in all treatments except for onion, bacteria mixed with feed significantly increased in fish growth performance compared to bacteria added to rearing water. Endophytic bacteria of onion and fenugreek recorded higher concentrations of protein in muscles than the control group by 56 and 49%, respectively. Furthermore, 88, 75 and 63% of the treatments recorded a decrease in albumin, ALT and AST concentration compared to the control group. Although the concentration of urea in the blood was higher than the control group by about 7.4 to 44.3%, but the challenge test showed that all treatments had a 20% mortality rate compared to the control group (10%). As a result, the endophytic bacteria of onion, brassicales and fenugreek can be used as probiotics for Nile tilapia. Further study is needed to elucidate the optimal bacterial concentration necessary for tilapia growth.

Dietary aflatoxin B1 and zearalenone contamination affected growth performance, intestinal and hepatopancreas gene expression profiles and histology of the intestine and gill in goldfish, Carassius auratus

The effects of dietary aflatoxin B1 (AFB1) and/or zearalenone (ZEA) contamination on goldfish, was investigated. Total of 540 fingerlings, 6.25 ± 0.12 g, were randomly allocated to experimental groups comprised of factorial designation of different dietary AFB1 (0, 50 and 100 ppb) and ZEA (0, 500 and 1000 ppb) concentrations for 60 days. Each treatment was conducted in triplicate. Results showed dietary AFB1 and/or ZEA depressed the growth performance of fish; the highest and lowest weight gain (WG), final body weight, thermal growth coefficient (TGC) and daily growth coefficient (DGC) were observed in control group and AFB50ZEA1000, respectively (P < 0.05). Moreover, dietary AFB1 and/or ZEA significantly affected the gene expressions of Caspase 3, Cytochrome P450 (CYP) 1A1, Glutathione S-transferases (GST) and Heat shock proteins 70 (HSP70) in a dose-dependent and tissue specific manner (hepatopancreas or intestine) (P < 0.05). In the hepatopancreas, the highest relative expression of Caspase 3 (2.08 ± 0.43), CYP1A1 (2.73 ± 1.18), GST (32.86 ± 4.03) and HSP70 (7.55 ± 2.35) genes were observed in AFB100ZEA1000, AFB50ZEA0, AFB0ZEA1000 and AFB0ZEA1000 groups, respectively (P < 0.05). However, the highest relative expression of Caspase 3 (39.70 ± 10.98), CYP1A1 (966.4 ± 68.6), GST (175.8 ± 37.1) and HSP70 (1.01 ± 0.22) genes in the intestinal tissue were observed in AFB100ZEA1000, AFB0ZEA1000, AFB100ZEA500 AFB0ZEA0 groups (P < 0.05). The highest scores of the intestine tissue inflammation (4.0 ± 0.75) and necrosis (4.0 ± 0.75) were observed in AFB100ZEA500 group (P < 0.05). The results indicated the significant contribution of the intestine in metabolism/excretion of the feed-born toxins. Furthermore, the results revealed that dietary AFB1 and/or ZEA contamination could negatively affect fish performance and detoxifying genes expression profiles at concentrations even lower than those indicated in the literature as the safe feed mycotoxin thresholds.

Integrated multitrophic aquaculture in ponds using substrate for periphyton as natural source of food

As a productive and sustainable alternative to fish farmers, the present study aims to evaluate the use of substrate for periphyton growth in an Integrated Multitrophic Aquaculture (IMTA) with complementary species. The studied species were: Nile tilapia (Oreochromis niloticus), grass carp (Ctenopharyngodon idella) and curimbatá (Prochilodus lineatus). The experiment had four treatments with three replicates that evaluated the IMTAs: [T100] Cb:C – tilapia inside hapas fed on recommended feed, with grass carp and curimbatás outside the hapas making use of natural food; [T50] Cb:C – the same species distribution with tilapia fed 50 % of the daily amount of commercial diet. Cb:C 100 and Cb:C 50 – grass carp and curimbatás fed on recommended feed at two feeding rates (100% and 50%) with substrate for periphyton growth in the feeding restriction treatment. In phase II, tilapias were included in all the treatments as a complementary species. Growth performance of fish and physical-chemical parameters of water were evaluated. In the proposed models, the species were efficient in utilizing the feed and in nutrient cycling, achieving productivity of 6 t/ha in the system without water renewal. Inserting secondary and complementary species reduced the feed conversion ratio (FCR) to values of 0.95 in systems under feed restriction and 1.28 in the groups that received 100% of commercial feed. Considering the reduction of the FCR and the high productivity, farmers can diversify their products in the same area without increasing inputs.

Effects of dietary citrus pulp level on the growth and intestinal health of largemouth bass (Micropterus salmoides).

Citrus pulp (CP) is rich in pectin, and studies have shown that pectin possesses antioxidant, anti-inflammatory, and gut microbiota-regulating properties. However, the application of CP in aquafeed is limited. In this study, the effect of dietary inclusion of CP on the intestinal health of largemouth bass (Micropterus salmoides) was investigated. Juveniles of similar size (6.95 ± 0.07 g) were fed isonitrogenous and isoenergetic diets containing different levels of CP (0%, 3%, 6%, 9%, 12%, or 15%) for 58 days. As the level of CP in the feed for largemouth bass increased, the fish's growth performance and intestinal health initially improved and then declined. Adding low doses of CP (≤9%) to the feed had no significant impact on the growth performance of large-mouth black bass, whereas high doses of CP (>9%) significantly reduced their growth performance. Adding 6%, 9%, or 12% of CP to that feed enhanced the expression of genes related to tight junctions, anti-inflammatory activity, anti-apoptotic activity, and antioxidant activity in the intestines of largemouth bass. It reduced intestinal inflammation and improved intestinal nutrient absorption, intestinal mucosal barrier function, and intestinal antioxidant capacity. Moreover, it improved the α-diversity, structure, and function of the intestinal flora. The addition of 6% CP had the most beneficial effect on the intestinal health of largemouth bass. On the other hand, the addition of 15% CP had adverse effects on the intestinal antioxidant capacity and intestinal mucosal barrier function of largemouth bass. Adding 6-9% CP to the feed for largemouth bass can improve their intestinal health without having a significant impact on their growth performance. CP could serve as a novel prebiotic and immunostimulant ingredient in aquafeed. © 2023 Society of Chemical Industry.

The Effect of Probiotics to Betta Fish (Betta splendens Regan, 1910) Aquaculture Performance

Betta fish (Betta splendens) is one type of ornamental fish that has high economic value. However, one of the obstacles on its cultivation activity is poor nutrition feed that support the enlargement process. One of the solution is adding probiotics. Probiotics can optimize fish growth, including betta fish. This study aimed to determined the best dose of the probiotics to increased the growth performance of betta fish. This study used a completely randomized design with 4 treatments and 3 replications (C: control, A: 5 ml/kg of feed, B: 7 ml/kg of feed, and C: 9 ml/kg of feed). The data was analyzed by Anova and Duncan’s test. Based on the parameters observed, it was shown that the addition of probiotics in commercial feed in treatment C (9 ml/kg feed) had a significant effect on the growth of absolute weight, SGR, and FCR.

Seaweed and Seaweed-Based Functional Metabolites as Potential Modulators of Growth, Immune and Antioxidant Responses, and Gut Microbiota in Fish.

Seaweed, also known as macroalgae, represents a vast resource that can be categorized into three taxonomic groups: Rhodophyta (red), Chlorophyta (green), and Phaeophyceae (brown). They are a good source of essential nutrients such as proteins, minerals, vitamins, and omega-3 fatty acids. Seaweed also contains a wide range of functional metabolites, including polyphenols, polysaccharides, and pigments. This study comprehensively discusses seaweed and seaweed-derived metabolites and their potential as a functional feed ingredient in aquafeed for aquaculture production. Past research has discussed the nutritional role of seaweed in promoting the growth performance of fish, but their effects on immune response and gut health in fish have received considerably less attention in the published literature. Existing research, however, has demonstrated that dietary seaweed and seaweed-based metabolite supplementation positively impact the antioxidant status, disease resistance, and stress response in fish. Additionally, seaweed supplementation can promote the growth of beneficial bacteria and inhibit the proliferation of harmful bacteria, thereby improving gut health and nutrient absorption in fish. Nevertheless, an important balance remains between dietary seaweed inclusion level and the resultant metabolic alteration in fish. This review highlights the current state of knowledge and the associated importance of continued research endeavors regarding seaweed and seaweed-based functional metabolites as potential modulators of growth, immune and antioxidant response, and gut microbiota composition in fish.