Growth Rate Of Fish Research Articles

Evaluation of Gamma Aminobutyric Acid and Sodium Butyrate in Juvenile Red Seabream (Pagrus major) Diets Containing Graded Levels of Fish Meal and Soy Protein Concentrate.

The experiment was conducted to evaluate the supplementary effects of gamma aminobutyric acid (GABA) and sodium butyrate (SB) when a graded level of fish meal (FM) was replaced with soy protein concentrate (SPC) in diets for juvenile red seabream (Pagrus major). A control diet was designed to contain 60% FM (F60). Two other diets were formulated by reducing FM levels to 40% and 20% with SPC (F40 and F20). Six more diets were formulated by adding 0.02% GABA or 0.2% SB to each F60, F40 and F20 diets (F60G, F60S, F40G, F40S, F20G and F20S). Each diet was randomly assigned to a triplicate group of fish (5.52 g/fish) and provided for eight weeks. Final body weight, weight gain and specific growth rate of fish fed F60G, F60S, F40G and F40S diets were comparable and significantly higher (p < 0.05) than other groups. The growth of fish fed SB-containing diets was significantly increased (p < 0.05) compared to fish fed the respective control diets. The feed efficiency and protein efficiency ratios were significantly higher (p < 0.05) in the fish fed all diets containing 60% and 40% FM compared to F20 and F20G groups. The F40S diet resulted in the highest feed utilization values. The F20S group exhibited significantly higher (p < 0.05) feed utilization than the F20 and F20G groups. Serum lysozyme activity was significantly higher (p < 0.05) in fish fed the GABA- and SB-containing diets compared to the F20 group. The F60S group exhibited the highest lysozyme activity which was significantly higher (p < 0.05) than in the F20 and F40 groups. Therefore, the growth performance, feed utilization and innate immunity of red seabream can be enhanced by dietary supplementation with GABA or SB in low-FM diets containing SPC. The FM level in the juvenile red seabream diet can be reduced to 40% with SPC and GABA or SB while maintaining performance better than a diet containing 60% FM.

Preliminary investigation of yaw stability in undulatory fish propulsion using stability derivatives

Fish are capable of maintaining a stable forward direction without yawing during long-distance movements. This long-term yaw stability has been investigated using static derivatives, revealing that undulatory locomotion is highly unstable. However, the present simulation of the perturbation development process shows that the yaw perturbation growth rate of the undulatory fish is an order of magnitude smaller than that of non-undulatory one. This study investigates the yaw stability of two-dimensional fish body undergoing the carangiform undulatory deformation by considering both the mean static and dynamic derivatives method. The results indicate that the yaw instability always occurs when the fish body is in undulatory propulsion or coasting model, and the undulation has stabilizing effect compared with the body straight in the uniform incoming flow. Analysis of the mean derivatives reveals that the stabilizing effect is due to the negative value of the dynamic derivative, which plays the role of damping, although the static derivative indicates that the yaw is unstable. Utilizing mean derivatives method can analyze qualitatively the linear stability at the equilibrium point, which cannot provide an assessment of overall stability.

Growth Patterns, Status of Well-Being and Trend Analysis of Three Commercially Important Clupeid Species from Selangor Landing Port

Length-weight relationships (LWRs) and condition factors are vital to quickly understanding the fitness and well-being of fish. There is currently no available evidence on LWRs, condition factors and landing trend for these three species and an absence of this information will result in improper management and monitoring of fish species. In this study, the growth patterns, status of well-being and trend analysis of commercially important clupeid species from the west coast of Peninsular Malaysia were studied. Sardinella lemuru, Amblygaster sirm and Nematalosa japonica were selected due to high commercial value and conservation status. S. lemuru was specifically categorized as near threatened by the IUCN with decreasing global populations. Total length (cm) and body weight (g) of S. lemuru, A. sirm and N. japonica were accounted for in this study, which was obtained from the wet market in the west coast of Peninsular Malaysia. The relationships between length and, weight and, condition factors (Fulton’s, KF; relative condition factor, Kn; Allometric) were assessed. The allometric equation; W = aLb was used to evaluate the length-weight relationships while KF = 100W/Lb and Kn = W/aLb were used to estimate fish condition factor. ARIMA (1,1,1) and ARIMA (0,1,0) models were utilised to forecast the fish landing pattern until 2030. The results showed that the coefficient of determination R2 values varied between 0.263 (Sardinella lemuru), 0.5187 (Amblygaster sirm) and 0.8443 (Nematalosa japonica) and b values ranged from 0.0959 to 2.1005. From this, all three fish species have shown a negative allometric growth pattern b&lt;3, reflecting a relatively slow growth rate and size of fish. No positive allometry was detected for any of the sampled fish species. A low value of relative condition factor (Kn &lt; 1) suggests that all the fish species in this study have poor physical characteristics due to inadequate food resources, and unsuitable habitats for expansion of the fish population. Prediction based on Autoregressive Integrated Moving Average (ARIMA) model showed that N. japonica would increase gradually in the coming years, while S. lemuru would remain constant. This study contributes to the knowledge base for S. lemuru, A. sirm and N. japonica in the west coast of Peninsular Malaysia, and is crucial in terms of understanding the ecology of the habitat for supporting conservation strategies, and the restoration and management of these species in future.

Effects of Bacillus cereusYB1 on growth, intestinal digestive enzyme activity, liver antioxidant enzyme activity, and intestinal structure of black rockfish, Sebastes schlegelii

AbstractWe aimed to investigate the effects of Bacillus cereus YB1 on the growth, intestinal digestive enzyme activity, liver antioxidant enzyme activity, and intestinal tissue structure of juvenile black rockfish (Sebastes schlegelii). A 50‐day feeding experiment was conducted. Feeding was conducted in four diet groups: control group with no YB1 supplement in diet and three treatment groups E‐L, E‐M, and E‐H containing 105, 106, and 107 CFU/g YB1, respectively. The results revealed that the weight gain and specific growth rate of juvenile fish significantly increased, while the feed coefficient was reduced in all three diet treatment groups. This indicated that the growth of black rockfish was significantly and positively affected by YB1 feeding. Enzyme activity in the intestinal tract was not significantly affected by YB1. However, the activity of protease, amylase, and lipase increased because of YB1 treatment, except for the proteases in the E‐M diet group. Meanwhile, no significant differences were recorded in the activities of the antioxidant enzymes in liver, but the level of catalase, superoxide dismutase, and malondialdehyde activities in treatments shows a better performance compared with the control in overall perspective. Furthermore, the structural features of the intestine (i.e., number of intestinal villi, length of gut villi, and thickness of muscularis) was significantly elevated with the inclusion of B. cereus YB1 in the diet. These results reveal that dietary supplementation of B. cereus YB1 is beneficial to the boosting of enzymatic activities and structure of intestinal tissue as well as the antioxidative ability of liver tissue. Such findings suggest that fish growth would be improved under YB1 feeding conditions.

Growth and survival performance of bileh fish (Rasbora sp.) added tarum leaf flour (Indigofera zollingeriana)

The catch of bileh fish (Rasbora sp.) has been caught from nature. Continuous fishing will lead to extinction in its habitat. Efforts made to anticipate this are carried out in the cultivation process. In fish farming, feed has a role as a source of nutrition for the growth process and survival of fish to be cultivated. Feed needs to support growth must have the right or appropriate nutritional content. The purpose of this study was to see the effect of adding tarum leaf meal (Indigofera zollingeriana) added to the feed by looking at the growth rate and survival of bileh fish (Rasbora sp.). This study used a complete randomized design (CRD), which consisted of four treatments then each treatment was repeated three times. The treatment.ie P0: control, P1: 10%, P2: 20%, and P3: 30% additional needle leaf flour. The test parameters observed were weight gain, length gain, feed conversion ratio, specific growth rate and survival. The results ANOVA test showed that the feed added with tarum leaf flour had a significant effect (P&lt;0,05) on length increase and specific growth rate, and there was no significant effect (P&gt;0,05) on weight gain, feed conversion ratio, and survival.

A probabilistic foundation for the study of larval fish feeding, growth, and mortality rates

Survival through the larval phase is predicated on the probabilities of successful feeding, which dictates growth rates, and the probabilities of encountering predators. Here I perform a synthesis of feeding, growth, and mortality rates estimated during several studies from coastal Newfoundland, Canada, to provide a description of the probability distribution that can serve as a foundation of the expected distribution of vital rates. The standardized observations clearly follow that of skewed distributions, appropriately fit to a probability gamma distribution, with feeding demonstrating a stronger degree of skewness than either mortality or growth, possibly because each vital rate integrates prey–predator interactions over different time scales. Commonality in the underlying form of the distribution of vital rates in larval fish, along with clear functional relationships between gamma parameters, represents a probabilistic basis of expectations against which observations from prior or new studies can be contrasted. An example of the use of such expectations demonstrates that they can provide useful contextual information about the contrast among observations and our ability to identify their relationship with environmental drivers.

Dietary Lycium barbarum Polysaccharide Modulates Growth Performance, Antioxidant Capacity, and Lipid Metabolism in Common Carp (Cyprinus carpio) Fed with High-Fat Diet.

To investigate the ameliorative effects and mechanism of Lycium barbarum polysaccharide (LBP) on growth performance, oxidative stress, and lipid deposition in common carp (Cyprinus carpio) fed with high-fat diets, fish with an initial weight of 5.29 ± 0.12 g were divided into five experimental groups-including normal-fat diets, high-fat diets, and high-fat diets-supplemented with LBP (0.5, 1.0, and 2.0 g/kg) for 8 weeks. The results showed that high-fat diets resulted in significant decreases in final body weight, weight gain rate, and specific growth rate of fish, as well as causing a significant decrease in hepatic total antioxidant capacity, catalase, and glutathione peroxidase activities. These changes were accompanied by a significant decrease in lipase activity and ATP level and a significant increase in malondialdehyde content. The expression levels of lipid metabolism-related genes (acetyl coenzyme A carboxylase 1, stearoyl coenzyme A desaturase 1, fat synthase, peroxisome proliferator-activated receptor-γ, fructofuranose bisphosphatase, and glucose-6-phosphatase) were also markedly elevated by high-fat diets. Supplementation with 0.5-2.0 g/kg LBP in high-fat diets improved the reduced growth performance, increased hepatic total antioxidant enzymes, catalase, and glutathione peroxidase activities, and lowered malondialdehyde level in fish fed with high-fat diets. Additionally, dietary supplementation with LBP significantly downregulated hepatic gene expression levels of acetyl coenzyme A carboxylase 1, stearoyl coenzyme A desaturase 1, fat synthase, sterol regulatory element-binding protein 1, peroxisome proliferator-activated receptor-γ, fructofuranose bisphosphatase, and glucose-6-phosphatase. In conclusion, fish fed with high-fat diets demonstrated impaired growth performance, antioxidant capacity, and lipid metabolism, and dietary supplementation with 0.5-2.0 g/kg LBP ameliorated the impairments induced by high-fat diets.

EFISIENSI PENGGUNAAN PAKAN TAMBAHAN DENGAN KANDUNGAN PROTEIN YANG BERBEDA TERHADAP LAJU PERTUMBUHAN DAN SURVIVAL RATE PADA BENIH IKAN KERAPU BEBEK (CROMILEPTES ALTIVELIS)

The purpose of the study is to determine efficiency of the use of additional types of feed with different protein content on the growth rate and survival rate of the fry grouper duck fish (Cromileptes altivelis). The method used in this research is the method of experiment which is a method of research by conducting a series of field trials of activities to see the results that may indicate position or relationship between variables clause - observed variables (Abdullah et al, 1985). From the research results can be obtained results growth rate grouper duck fish seed is highest on P3 is 0.052 grams / day and was lowest for the P4 is equal to 0,023 grams / day. While the value of the highest survival rate was obtained in P3 which anchovy at 95% and lowest for the meat snails P2 is only 25%. But at this result meat snails can obtain results that exceed the growth rate of fish peperek. The value of feed efficiency in P3 with a protein content of 63% is the highest efficiency rate is 23.16% and the lowest at 15.37% efficiency found in P4 with a protein content of 34%.

Prebiotic, probiotic and marine algae suplementation in juvenile tilapia diet

This study evaluated the probiotic mannan oligosaccharide (MOS), and marine algae for Nile tilapia (Oreochromis niloticus) feeding. The parameters analyzed were fish-growth rate, hematological and immunological parameters, and intestinal microbiota. Also, fish were submitted to experimental infection challenge with Aeromonas hydrophila to evaluate the immune response. Nile tilapia juveniles (weight 8.86 ± 3.22 g) were used in the six treatments with four replicates, for 63 days. The treatments were: control basal diet; PAS-TR: basal diet plus 0.04 g·kg-1 of the probiotic (Bacillus cereus and Bacillus subtilis); MOS: basal diet plus 4 g·kg-1 of the prebiotic mannooligosaccharide, 4 g·kg-1 of the prebiotic Kappaphycus alvarezii. Two more diets were formulated by a combination of PAS-TR + MOS (4 +4 g·kg-1), and PAS-TR + KAP (4 +4 g·kg-1). For the challenge experiment, the fish were fed for 21 days, infected via intraperitoneal injection with A. hydrophila (1 x 106 UFC·mL-1), and the mortality rate was registered for 15 days post-infection. Results indicated the capacity of probiotic to remain in the gut for 63 days, and it was inhibited neither by autochthonous microbiota nor by prebiotics used. The feed additives tested for Nile tilapia did not cause a beneficial or adverse effect on growth or hematological variables. However, these treatments protected the fish from A. hydrophyla infection, proved by higher survival rate, and relative protection levels. We concluded that probiotic PAS-TR and prebiotics MOS and KAP, combined or not as symbiotics, may promote immune protection and reduce the mortality rate of A. hydrophyla infection.

The Effect of Short-Term Artificial Feed Domestication on the Expression of Oxidative-Stress-Related Genes and Antioxidant Capacity in the Liver and Gill Tissues of Mandarin Fish (Siniperca chuatsi).

To investigate whether Mandarin fish developed oxidative stress after being domesticated with artificial feed, we conducted a series of experiments. Oxidative stress is an important factor leading to diseases and aging in the body. The liver integrates functions such as digestion, metabolism, detoxification, coagulation, and immune regulation, while the gills are important respiratory organs that are sensitive to changes in the water environment. Therefore, we used the liver and gills of Mandarin fish as research materials. The aim of this study was to investigate the effects of short-term artificial feed domestication on the expression of oxidative stress genes and the changes in oxidative-stress-related enzyme activity in the liver and gills of Mandarin fish. We divided the Mandarin fish into two groups for treatment. The control group was fed with live bait continuously for 14 days, while the experimental group was fed with half artificial feed and half live bait from 0 to 7 days (T-7 d), followed by solely artificial feed from 7 to 14 days (T-14 d). The experimental results showed that there was no difference in the body weight, length, and standard growth rate of the Mandarin fish between the two groups of treatments; after two treatments, there were differences in the expression of genes related to oxidative stress in the gills (keap1, kappa, gsta, gstt1, gstk1, SOD, and CAT) and in the liver (GPx, keap1, kappa, gsta, gstt1, gr, and SOD). In the liver, GPx activity and the content of MDA were significantly upregulated after 7 days of domestication, while in the gills, SOD activity was significantly upregulated after 7 days of domestication and GPx activity was significantly downregulated after 14 days of domestication. These results suggest that artificial feed domestication is associated with oxidative stress. Moreover, these results provide experimental basic data for increasing the production of aquaculture feed for Mandarin fish.

Approaches to Use Anti-nutritional Factors Containing Plant Based Protein-rich Aquafeeds

Replacement of the fish meal as a protein source in the aquafeeds is required these days due to the high cost of fish meal and its uncertain availability. Aquatic animals rely on fish meal for protein source so the protein source used in place of fish meal must not alter the nutritional quality of the feed. Therefore, such alternatives include animal and plant by- products such as meat, bone meal, rapeseed meal, soybean meal, corn gluten meal, a meal of protein- rich leaves, etc. However, the presence of anti-nutritional substances such as phytic acid, tannin, saponin, cyanide, oxalate, phytoestrogens, and gossypol limits the use of plant ingredients because ANFs have various side effects such as poor intestinal inflammation, oxidative stress, and decreased growth rate in many fish. To reduce the harmful effects several techniques such as solvent extraction, dry and wet heating, enzyme treatment, etc are used to reduce or eliminate such toxic components from Aquafeed. Amelioration strategies help in removal of anti-nutritional factors from plant based extract and are helpful in production of nutrient- rich and cost effective feed for fish for better growth and viability.

Effect of stocking density of Snakeskin gourami (Trichopodus pectoralis) in polyculture system with Black apple snail (Pila polita)

The experiment determined the effect of stocking density of snakeskin gourami in the polyculture model with black apple snails. The experiment included four treatments corresponding to four densities of fish (ind./m2): (i, Control): 0, (ii) 3, (iii) 5, and (iv) 7; snails were stocked at 150 snails/m2; each treatment was triplicated. The initial fish’s weight was 12 ± 0.3 g, and the snail’s weight was 0.15 ± 0.01 g. After 120 days of the experiment, the survival rate of fish was 100% in all treatments, whereas the survival rate of snails ranged from 80.22 to 82.44%, and there were no significant differences (p&gt;0.05). Snails in the control treatment obtained the highest specific growth rate (2.68 %/day) and productivity (0.54 kg/m2). In contrast, the specific growth rate and productivity of fish obtained the highest number in treatment iv, with 0.98 %/day and 0.24 kg/m2, respectively. The highest profit was recorded in the treatment with 7 fish/m2, and this was significantly different (p&lt;0.05) compared to the control and 3 fish/m2 treatment. Results from this study showed that the stocking density of 5 fish/m2 was suitable to enhance productivity of both snail and snakeskin gourami in polyculture system.

Growth and Immunity Performance of Nile Tilapia (Oreochromis niloticus) Challenged by Toxicity of Bio-Insecticide with Active Ingredients Eugenol and Azadirachtin

This study aims to determine the maximum concentration and the long-term effects after exposure to a bio-insecticide with active ingredients eugenol and azadirachtin on the survival rate, immunity, and growth of Nile tilapia. The method used in this study was experimental, using a completely randomized design (CRD) with six treatments and three replications. Fishes were exposed to eugenol and azadirachtin at concentrations 10, 20, 30, 40, and 50% of LC50 value for 14 days, followed by 14 days of maintenance to see the effect on growth. The results showed that 66 mg.L-1 treatment was a concentration that did not interfere with the survival rate of Nile tilapia, which was 86.7%. The number of leukocytes increased on the third day by the highest increase in 66 mg.L-1 treatment at 12.01 × 104 cells.mm-3. Meanwhile, erythrocytes decreased, with the highest decrease in 66 mg.L-1 treatment at 1.13 × 106 cells.mm-3. The average growth rate in fish slowed down with increasing concentrations of exposure, with the lowest average growth in length and absolute weight in the 66 mg.L-1 treatment was 0.57 cm and 1.68 g.

Application Of Lights in The Nursery of Snubnose Pompano Trachinotus blochii (Lacepède, 1801) In Ponds as An Effort to Increase Feed Cost Efficiency

The snubnose pompano (Trachinotus blochii), which is an introduced fish, is currently in increasing demand, both for the domestic market (Jakarta and other big cities) and international markets such as Singapore, Taiwan, Hong Kong, and China. The snubnose pompano can be cultivated in ponds because it is tolerant to changes in salinity (5-40 ppt). In this study, the use of lights installed in cages used to maintain the snubnose pompano nursery will be responded to natural food that is positively phototactic (zooplankton, shrimp, and small fish species) which will gather as feed at night. So, it is hoped that the use of these organisms as an alternative feed source can increase feed efficiency. The urgency of this research is to determine efforts to save on the use of artificial feed and to suppress parasite attacks. A t-test was carried out to compare the averages of two different samples, on the growth rate and health of snubnose pompano fish. Research using lights resulted in optimum growth of snubnose pompano with 100% survival rate, feed conversion ratio (FCR) value of 0.9 and produced snubnose pompano size 80–100 g/head within two months as well as healthy fish seeds. With indicators of parasitic attack that are lower than the treatment without light with a prevalence value of 25% (with lights); range of 25%-75% (without lights) and intensity 6-8 (with lights); range 11-35.67 (without light). The snubnose pompano seeds are always actively moving when the light is on, the use of the light can effectively catch organisms such as small shrimp or small crustaceans so that the snubnose pompano seeds can be used to be digested as an alternative food (as observed in the stomach contents and intestines of the snubnose pompano). The light also indicates that parasitic attacks on the snubnose pompano are less common.

The Effect of Probiotic-Induced Fermentation of Restaurant Waste on the Growth of Common Carp (Cyprinus carpio) Fry

The study explores using the fermentation process to convert organic restaurant waste into fish feed, a promising solution for aquaculture. The aim is to determine the best type and dosage of probiotics for fermenting restaurant waste (FRWM) and evaluate their impact on common carp (Cyprinus carpio) fry growth. Three commercial probiotics (P1, P2, and P3) were used at an 8% concentration for fermenting the waste. The best result from the fermentation trial was tested as feed containing different FRWM proportions: 0% (TA), 10% (TB), 20% (TC), 30% (TD), and 40% (TE) with 30% protein content. The trial lasted 42 days, assessing waste chemical composition before and after fermentation, growth rate, amylase and protease activity, feed conversion, survival rate, and water quality. Results showed P1 was most effective, increasing FRWM protein content by 84.25% and reducing crude fiber and fat by 15.17% and 3.94%, respectively. TE (40% FRWM) yielded the best outcomes, with fry common carp achieving a 1.05% daily growth rate and a feed conversion ratio of 0.80, indicating efficient feed utilization. TC (20% FRWM) exhibited the highest survival rate at 88.33%. The inclusion of FRWM influenced amylase activity, increasing enzyme levels and improving feed efficiency and growth rate. In conclusion, using FRWM, fermented with P1 probiotics, showed significant improvements in its composition, leading to enhanced fish growth and feed utilization. The 40% FRWM diet demonstrated the best fish growth rate and feed conversion performance. These findings support using fermented restaurant waste as sustainable and nutritious fish feed in aquaculture.

Comparative Study of Bisphenol-A and its Analogue Bisphenol-S on Growth and Condition Factor of Juvenile Zebrafish (Danio rerio)

Bisphenol-A is a synthetic estrogen highly used in the production of polycarbonate plastics and epoxy resins in plastic industry world-wide. Bisphenol-A presents as a ubiquitous environmental contaminant in all ecosystems. Bisphenol-A is an endocrine disruptor which affects the growth, development and physiology of living organisms. Therefore, bisphenol-S has been introduced as a safe alternative to bisphenol-A and it has become the widely used bisphenol-A substitute. Bisphenol-S has also been identified as an endocrine disruptor and emerging environmental contaminant. Therefore the safety of bisphenol-S substitution has become questionable. Thus, this study was carried out to comparatively assess the impacts of bisphenol-A and bisphenol-S exposure on growth and condition factor of zebrafish (Danio rerio). After 7-days acclimatization period, twenty juvenile zebrafish of 67 dpf (days post fertilization) of age were treated 35 days with 10 μg/L and 100 μg/L of bisphenol-A, bisphenol-S and with treatment control in triplicate tanks. Mean body length, weight, specific growth rate and condition factor of fish were evaluated. Mean body weight increment of zebrafish under 100 μg/L of bisphenol-S and bisphenol-A were significantly different from the treatment control (p&lt;0.05, One way ANOVA, Tukeys pairwise Comparison). The mean body length increment and specific growth rate were not significant under both concentrations of bisphenol-S and bisphenol-A with treatment control (p&gt;0.05). However, the condition factor of fish under both concentrations of bisphenols were significantly less than control (p&lt;0.05). The condition factor of fish under comparable concentrations of bisphenol-S and bisphenol-A were not statistically significant. Therefore, it can be concluded that exposure to environmental concentrations of both types of bisphenols could affect the wellbeing of juvenile zebrafish. Based on the findings, bisphenol-S cannot be recommended as a safe substitution to bisphenol-A. Yet, more comprehensive studies are recommended to evaluate relative effect of bisphenol-S on freshwater ecosystem health. &#x0D; Keywords: Body length, Body weight, Condition factor, Bisphenol-A, Bisphenol-S, Zebrafish, (Danio rerio)

Modular system innovation for increasing milkfish production on traditional ponds in Usto village, Mare district, Bone

One of the milkfish cultivation techniques (Chanos chanos) to increase pond productivity is a modular system. Modular system is a pond cultivation technique with a tiered plot model, where connecting between ponds is made, the purpose of which is to make milkfish easily move between ponds. The purpose of this study is to analyze the effectiveness of modular system innovation techniques (tiered plots) in increasing the production of bait milkfish in traditional ponds in Usto Village, Mare District, Bone. The research was conducted from August to the end of November 2023, at the location of the 2023 Matching Fund - Kedaireka program in a traditional pond in Usto Village, Mare District, Bone Regency, South Sulawesi Province. The research method used is a quantitative research method with a type of experimental research. Primary data measurements include; water quality measurement, including; temperature, salinity, pH and dissolved oxygen. While the parameters of the organization include the length of the fish from stocking to harvest. The data analysis method used is descriptive statistical analysis, in order to obtain an overview of the success of modular system techniques in traditional ponds. The results of the study obtained that the modular system technique can increase fish growth quickly, with the process of transferring fish periodically between ponds, making fish experience different conditions and physiological conditions that feel new. The modular system provides an average fish growth rate of 4.5 cm within 3 months or an average of 0.15 cm per day, with the highest rate occurring in rearing pond I, which is during the initial phase of post-stunting maintenance, which is an average growth rate of 6.2 cm per month, or 0.21 per day. Thus, this modular system technique can be used to increase the productivity of traditional ponds.

Smoltification, seawater performance, and maturation in Atlantic salmon (Salmo salar) fed different fat levels

IntroductionThe use of recirculating aquaculture systems (RAS) to produce Atlantic salmon smolts has resulted in exceptionally high fish growth rates. However, there are potential negative trade-offs between fast growth and key physiological processes, such as inadequate smoltification and early sexual maturation, which can both be linked to body energy reserves.MethodsThis study determined the effect of i) dietary fat levels on Atlantic salmon whole-body fat and fatty acids composition, growth performance and smoltification and ii) a previous dietary regime on seawater growth performance and male early sexual maturation. In freshwater RAS, salmon parr (~19g) were fed 3 fat levels (20, 24, and 28%) over a 14-week period at 12°C. Subsequently, in seawater flow-through systems, smolt (~96g) were fed a control diet (26%) for 12 weeks at 2 temperatures (12 and 16°C).ResultsDietary fat levels resulted in differences in k-factor, fish whole-body fat and fatty acids composition; the low fat diet resulted in fish with a 23% lower whole-body fat when compared to the other two dietary groups at the end of the freshwater phase. These differences in whole-body fat faded at the end of the seawater phase. During the freshwater phase, all three feeds resulted in a comparable growth performance and smoltification indicator values, including k-factor, gill Na+, K+-ATPase, blood serum chloride and smolt index score. In contrast, water temperature resulted in fish body weight differences, where groups reared at 16°C were larger than those reared at 12°C. Nevertheless, both temperature regimes supported a similar thermal growth coefficient. Smolts grown at 16°C showed a higher level of the sex steroids androstenedione compared to those at 12°C. However, 11-ketotestosterone and testosterone levels did not differ despite a trend for higher levels at 16°C. Furthermore, testis histology at the final sampling indicated that some individuals showed initial signs of maturation (stage 3).DiscussionIn conclusion, varying dietary fat levels (20 - 28%) during the freshwater phase did not influence smoltification or male early sexual maturation during the subsequent grow-out phase. However, a temperature increase from 12 to 16°C resulted in larger fish and appeared to stimulate early male maturation in some fish individuals.

Experience of breeding char (genus Salvelinus) under industrial fish harvedy farming conditions

Of undoubted interest is the introduction into the aquaculture of the region of such a species native to the basins of the Kara and Laptev seas as the Arctic char Salvelinus alpinus (L.). A number of biological features of this species give special relevance to the prospects of the char as an object of aquaculture. The purpose of the work is experimental research and experience in breeding Arctic char using the example of the freshwater form of char on the Taimyr Peninsula. Information provided. Objectives: to study the conditions of keeping, feeding and growth characteristics of freshwater char when kept in cages on the Yenisei River. The object of the study was the freshwater form of char of the Taimyr Peninsula of generations 2021–2022. The study was carried out at two sites of Maltat LLC (Balahtinsky district of the Krasnoyarsk Territory, fish breeding farm in the city of Divnogorsk near the dam of the Krasnoyarsk hydroelectric power station) and at the Department of Breeding, Genetics, Biology and Aquatic Bioresources of the Federal State Budgetary Educational Institution of Higher Education Krasnoyarsk State Agrarian University. Environmental conditions, growth characteristics, growth rate and waste (mortality) were determined. When growing, granulated feed produced by Coppens were used. It has been shown that the weight of fish during cage rearing is higher than that of loaches from their native range. The growth rate of fish is minimal in January (about 2%), maximum in June-July. Freshwater char during cage cultivation on artificial feeds in the lower reaches of the Krasnoyarsk hydroelectric power station shows high weight growth characteristics exceeding those of fish from native habitats. Thus, research has confirmed the feasibility of factory reproduction of freshwater char from reservoirs of the Taimyr Peninsula in cages on the Yenisei River.

The effect of a complex bajillary microbiological preparation on the growth and indicators of the internal environment of the body in juvenile siberian sterlet Acipenser ruthenus marsiglii Brandt

Probiotic drugs are a product of agricultural biotechnology. Their use for feeding fish and other aquatic organisms, especially coldwater ones, is currently insufficiently studied. The addition of a bacillary probiotic preparation (based on two species of bacteria of the genus Bacillus in fish feed) was carried out. These microorganisms are symbionts of many warm-blooded animals and are not a specific intestinal microflora of sturgeon. Experimental work was carried out in the UZ of the Aquaculture Research Center of the Novosibirsk State Agrarian University. Studies have shown that the addition of a bacillary probiotic drug in doses of 500 and 1000 mcg per kg of feed when feeding juvenile sterlet weighing 0.27–0.29 kg to a weight of 0.375–0.384 kg for 40 days did not have a positive effect on fish growth in experimental groups. All physiological parameters, such as oxygen consumption, the state of white and red blood, lay within the limits typical for sturgeon fish contained in the ultrasound. At the same time, there is an increase in leukocytosis in fish in the group receiving 1000 mcg/kg of feed within 106,7±16,7–143,8±56,3×103/mcl by an average of 22.3% compared to the control. The oxygen consumption level in the fish in the control group was 18.7–28.31% lower than in the experimental ones. There were no significant changes in the growth rate of fish receiving different doses of the drug. The average daily increase in the group receiving 500 mcg/kg of feed was 4.52 g per day, 1000 mcg/kg — 4.44 g per day. On average, on the 30th day of observations, when compared with the control, the growth rate of juvenile sterlet in the experimental groups was lower by 25.16 and 38.6%. At the same time, the safety of fish in the control group was 96.55, and in the experimental group it was 100%.