Fish Farming Research Articles

Technological approaches for commercial production of functional food through fish farming: Opportunities and challenges

Functional foods and nutraceuticals have gained attention as a result of the emergence of several human health disorders, including abdominal, obesity, diabetes, cardiovascular diseases, and neurodegeneration. The components of functional foods influence the physiological system, which enhances human health and fights against illness. The global consumption of fish and fish products has increased in recent years, driven by the presence of omega-3 fatty acids, oligosaccharides, glucosamine, vitamins A, D, and E, as well as minerals such as magnesium, potassium, copper, sulfur, zinc, iodine, and proteins. It is widely acknowledged that functional food ingredients are important for promoting health, lowering the risk of disease, and lowering medical expenses. Fish farming has emerged as a source of novel functional ingredients from marine resources for functional food as well as for therapeutics. The review paper will also cover various technological approaches such as CRISPR-Cas9 mediated gene editing, zinc finger nucleases, and TALENs for enhanced production of bioactive compounds from genetically modified fishes for commercial production of functional food as well as nutraceuticals. Keywords: Fish farming, Zinc finger nuclease, CRISPR/Cas9, Functional food, Nutraceuticals, Omega-3 fatty acids

Synthesis of Fe3O4/CNT@PDA/HAP hybrid nanocomposite for the removal of malachite green from water in fish farming

Synthesis of Fe3O4/CNT@PDA/HAP hybrid nanocomposite for the removal of malachite green from water in fish farming

Farmers’ knowledge of using flood forecast information in fish farming: A case of rural Bangladesh

The effects of global climate change and extreme weather events are threatening Bangladesh's fish and aquaculture productivity. Given the negative consequences of climate change, both the national and international societies concur that mitigating the effects of climatic unpredictability and change requires the development of weather and climate services. Additionally, if forecasting data is expertly adapted to fish farmers' requirements, they may be better able to handle and adjust to climatic and climatic-induced stressors. The primary goal of the study was to determine how much fish farmers knew about using flood forecast information regarding fish farming. Three villages in the Union Islampur upazila, which is part of the Jamalpur district, were the sites of the study: Kulkandi, Chinaduli, and North-Bamna. A sample of 95 randomly chosen fish farmers (about 25% of the total population) out of 380 fish farmers provided the data. Focus groups, matrix ranking, and key informant interviews were among the qualitative and quantitative techniques used in the study's research methodology. In order to collect both quantitative and qualitative data, formal and semi-structured questionnaires were created. The majority of farmers (53.90%) had a medium level of knowledge, followed by high knowledge (31.57%), and poor knowledge (14.74%) about the use of forecast information in fish farming. Therefore, through a variety of interventions, including training, group discussions, demonstrations, and the distribution of printed materials, concerned authorities like the Department of Fisheries (DOF) should provide chances to increase the knowledge of fish farmers. Regression study revealed that farmers' knowledge regarding using forecast information in fish farming is positively impacted by their level of education, annual earnings from fish farming, organizational participation, and sources of flood forecast information. Therefore, while creating programs and making decisions, legislators, development practitioners, extension specialists, and others should consider these aspects. Int. J. Agril. Res. Innov. Tech. 14(2): 9-19, December 2024

Training on Making Simple Basic Fish Feed to Improve the Skills of Fish Farmers Milkfish

The people of Aeramo village, Nagekeo Regency, who work as fish farmers, find it very difficult to provide fish feed due to the high feed price. The purpose of implementing this community service activity is to provide information about the process of making simple-based fish feed and their response. Community service was carried out in June 2023 in Dusun II, Aeramo Village, Nagekeo Regency. The activity method is Asset Based Community Development (ABCD), which aims to carry out community service based on the strengths and potential of the community. Discussions and interviews, counseling, and direct practice carried out data collection. The results obtained from this fish feed-making training activity are: 1) the community knows that the actual feed they buy so far ingredients are around them and are very simple, 2) the community is able to absorb the knowledge gained about how to make feed starting with the preparation of tools and materials, making formulations, to making feed and given directly to cultured fish. Fish farmers can easily make fish feed, and the raw materials used in making feed can be obtained in the surrounding area, making it easier for farmers to make their feed.

The immunomodulatory and antioxidative effects of curcumin-supplemented diets against the isolated Aeromonas hydrophila in Oreochromisniloticus.

Worldwide, Aeromonas hydrophila (A. hydrophila) has become a significant foodborne pathogen, causing gastrointestinal and extra-intestinal infections in humans as well as severe economic losses in fish farms. Thus, we conducted this research in two experiments. The experiment 1 investigated the prevalence of A. hydrophila among Nile tilapia in different farms in Kafrelsheikh province and its pathogenicity by detecting some of its virulence genes before being used in the in vivo experiment. The experiment 2 was done to investigate the effect of dietary curcumin on growth performance, humoral immunity, antioxidants, and histopathology of Nile tilapia through a sixty-day feeding trial. Nile tilapia was divided into 3 groups, each in 3 replicates. Fish were given diets that included 0.0 (C, control), 1% (10g curcumin/kg diet; G1), and 2% curcumin/kg diet (20g curcumin/kg diet; G2). Moreover, the antibacterial effect of dietary curcumin against isolated bacteria in experiment 1 was investigated through experimental infection. The study's findings of experiment 1 indicated that the incidence of isolated A. hydrophila was 28%. Moreover, the virulence aerolysin (aerA) and haemolysin (hlyA) genes were found in 100% and 50% of the isolates, respectively. The experiment 2 outcomes demonstrated that the growth-modulating impacts of dietary curcumin were notably noticed in final weight, feed intake, weight gain%, and specific growth rate without pathological lesions in the different organs. In addition, the white blood cell and lymphocyte counts significantly (P<0.05) increased in Nile tilapia fed dietary curcumin. Similar improvements in humoral immunity (lysozyme and phagocytic activity) and antioxidants (catalase and superoxide dismutase) were seen in the 1% curcumin group (G1). The experimental infection with a virulent strain of A. hydrophila that was previously isolated in experiment 1 showed a significant decrease in the morbidity and mortality rates in the 1% curcumin treatment group (G1), followed by the 2% group (G2). The present study concluded that under current experimental conditions, dietary curcumin at a dose of 10g/kg diet proves effective, but the dose of 1% may not be optimal for tilapia.

Contrasting hair mercury in fishermen and workers of fish industry of Marano Lagunare (Upper Adriatic Sea), a coastal lagoon area contaminated by mining and industrial activities, against residents from the Dolomites Alps.

This survey aimed at estimating the concentration of hair mercury (Hg) in fishermen and workers of fish industry of Marano Lagunare (North-eastern Italy, Upper Adriatic Sea). A field investigation was conducted from 2nd of December 2023 through 18th April 2024, on 73 local fishermen, 83 workers of fish industry and 93 controls among residents (mainly farmers/herdsmen) of the Dolomites Alps. An amount of approximately 100mg of hair was collected from all respondents, who were also asked to fill out a self-administered questionnaire collecting socio-demographic and lifestyles information. The median hair Hg concentration was 2.56mg/kg in fishermen, 2.31mg/kg in workers of fish industry and 0.58mg/kg in controls. Compared with controls from the Dolomites, log-transformed hair Hg increased linearly with the amount of fish consumed (>1 meal per week), consumption of fresh fish and was significantly higher in fish dealers/fish restaurateurs and fishermen, regardless if operating on open sea or lagoon. All study groups but fish farmers and local residents involved in other business exhibited significantly higher odds of hair Hg >2mg/kg at multiple logistic regression analysis. Whilst above the threshold background exposure recommended by WHO for the general population, the median levels of hair Hg in fishermen and workers of fish industry of Marano Lagunare were still below the cut-off of no health effects observed on human health (11.5 mg/kg). The above evidence most likely reflects contamination of lagoon bed and respective tributary river beds by sedimentary Hg from mining and industrial activities, with subsequent transfer of the metal into the aquatic trophic chain and from there to humans through consumption of local fish.

Seasonal Dynamics of Caligus clemensi Infestation in European Seabass and Flathead Grey Mullet Integrating Morphological, Molecular, Immunological, and Environmental Perspectives

This case study investigates the seasonal prevalence, morphological characteristics, molecular identity, host immune response, and environmental factors influencing Caligus clemensi infestations in farmed European seabass and flathead grey mullet at a single marine fish farm. A total of 600 fish (400 seabass, 200 mullet) were examined over one year, revealing seasonal fluctuations in parasite prevalence and intensity. C. clemensi infestation peaked in winter for seabass (75% prevalence) and spring for grey mullet (80% prevalence), with notable declines in summer and autumn for both species. Morphological analysis confirmed C. clemensi as the causative agent, exhibiting sexual dimorphism and characteristic features including a quadrilateral cephalothorax and disk-shaped lunules. Molecular characterization of the 18S rRNA gene corroborated the morphological identification, with phylogenetic analysis revealing a well-supported monophyletic clade for C. clemensi within the family Caligidae. Quantitative real-time PCR demonstrated significantly elevated interleukin-1β (IL-1β) expression in infected fish, indicating a robust inflammatory response. Grey mullet and seabass exhibited high IL-1β upregulation. Histopathological examination revealed severe gill tissue damage, vascular changes, and hepatic steatosis in infected fish. Water quality analysis identified several parameters exceeding permissible limits, including total suspended solids (4800-5100 mg/L), total dissolved solids (32000 mg/L), sulfates (2300 mg/L), and chlorides (18000 mg/L). These elevated levels, likely associated with nearby oil production and refining activities, created conditions conducive to parasite proliferation. The high total suspended solids might provide substrates for C. clemensi settlement and attachment, while increased dissolved ions could stress fish and reduce their parasite resistance. This multidisciplinary case study revealed complex host-parasite interactions between C. clemensi and farmed marine fish, highlighting the need for improved water quality and targeted parasite control to enhance aquaculture sustainability in the Suez Canal region.

Environmental impacts of fish cage cultures in the southern Caspian Sea.

In the last two decades, cage culture industries have developed in Iranian seas, supplying a portion of the needed protein and contributing to food security. In this paper, environmental impacts of cage culture are investigated, focusing on the physical, hydrodynamical, chemical, geological, and biological oceanographic aspects at the Abbas Abad fish farm in the southern Caspian Sea. Multidisciplinary field measurements were conducted from fall 2018 to late summer 2019 in different oceanographic aspects. Results showed that the cages have not significantly affected the hydrodynamics and physical parameters of the aroundwater, and have actually caused a slight decrease in current speed within a few 10m of the cage. The maximum levels of inorganic phosphates, total phosphorus, total organic phosphorus, nitrite, nitrate, ammonium, total nitrogen, silicate, BOD5 and COD were 22ppb, 34.91ppb, 26.92ppb, 6ppb, 103.69ppb, 69.5ppb, 1423.99ppb, 679.06ppb, 1.9 mg/l, 80 mg/l respectively. The water quality is considered safe and not concerning based on levels of phosphate, nitrite, nitrate, ammonium, BOD5, and COD. Also, planltonic (phyto and zooplankton) and benthic communities and benthic around the cages were the same with sourounding waters. This paper presented comprehensive information about the effects of cage culture farms on the surrounding waters of the Caspian Sea.

Low-cost prototype for real-time analysis using liquid crystal optical sensors in water quality assessment

In the food production sector, quickly identifying potential hazards is crucial due to the resilience of many pathogens, which could lead to wasted production results and, more severely, epidemic outbreaks. E. coli monitoring is essential; however, traditional quality control methods in fish farming are often slow and intrusive, thus promoting an increase in fish stress and mortality rates. This paper presents an alternative method by utilizing a prototype inspired by polarized optical microscopy (POM), constructed with a Raspberry Pi microprocessor to assess pixel patterns and calculate analyte levels. The sensors are based on the immune complexation reactions between E. coli specific antibodies and the disruption of liquid crystal (LC) alignment, which are measured with the POM technique. The prototype yielded a sensitivity of 1.01%±0.17%/log10 (CFU/mL) for E. coli. In this paper, tests using sunlight as the prototype’s light source were also performed, and a user-friendly graphical user interface was designed.

Gonadal miRNomes and transcriptomes in infected fish reveal sexually dimorphic patterns of the immune response.

Fish disease outbreaks caused by bacterial burdens are responsible for decreasing productivity in aquaculture. Unraveling the molecular mechanisms activated in the gonads after infections is pivotal for enhancing husbandry techniques in fish farms, ensuring disease management, and selecting the most resilience phenotype. The present study, with an important commercial species the European sea bass (Dicentrarchus labrax), an important commercial species in Europe, examined changes in the miRNome and transcriptome 48h after an intraperitoneal infection with Vibrio anguillarum. The findings indicate that following infection, testes exhibited more pronounced alterations in both the miRNome and transcriptome. Specifically, males showed approximately 26% more differentially expressed genes in testicular genes compared to females (2,624 vs. 101 DEGs). Additionally, four miRNAs (miR-183-5p, miR-191-3p, miR-451-5p, and miR-724-5p) were significantly expressed post-infection in males, while none were identified in females. Interestingly, upon deep analysis of sexual dimorphic gene modules, a larger number of miRNAs were identified in infected females targeting genes related to the immune system compared to infected males. These results suggest that fish ovaries demonstrate greater resilience in response to infections by suppressing genes related to the immune system through a post-transcriptional mechanism performed by miRNAs. In contrast, testes activate genes related to the immune system and repress genes related to cellular processes to cope with the infection. In particular, the crosstalk between the miRNome and transcriptome in infected males revealed a pivotal gene, namely, insulin-like growth factor binding protein (igfbp), acting as a gene network hub in which miR-192-3p was connected. The current study elucidated the need to comprehend the basic immune regulatory responses associated with miRNAs and gene regulation networks that depend on fish sex. The data reveal the importance of considering sex as a factor in interpreting the immune system in fish to generate efficient protocols to prevent outbreaks in fish farms.

Anatomical differentiation of the ovary in pseudotolithus typus from the Ivorian marine coast

Overexploitation of fish resources causes the scarcity or even extinction of certain species. Fish farming appears to be the solution. The objective of our work was to understand the morphological differentiation of the ovary in Pseudotolithus typus in order to control its reproduction. The sex and stage of sexual maturity of the fish were determined after dissection. The present work showed that the ovary of Pseudotolithus typus is formed of 2 lobes and presented 6 stages of sexual maturity.

Herons in Aquafarms Are More Fearful of Humans.

Herons (Ardeidae), an important group in wetland ecosystems, have a particularly strong relationship with humans. However, their predation on farmed fish and shrimp in aquafarms can lead to economic losses for local fish farmers. Consequently, notable conflicts arise between fish farmers and herons. Fish farmers adopt various measures to deter herons from "stealing" their fish; however, there is limited research on the behavioral responses of herons under such pressures of human disturbance. Flight initiation distance (FID) is an important manifestation of avian anti-predation behavior and serves as an indicator of birds' tolerance to human disturbance. This study investigated the potential variations in tolerance to human disturbance between the little egret (Egretta garzetta) and the Chinese pond heron (Ardeola bacchus) in "stealing" environments (aquafarm environments) and non-aquafarm environments in Hainan and Guangdong Provinces, south China, using FID as an indicator. Herons in aquafarm environments were less tolerant (having longer FIDs) to human disturbance compared to herons in non-aquafarm environments. The main cause of this phenomenon could be the harsh deterrents used by humans to prevent herons from "stealing" fish. These deterrents increase the predation risk for herons when "stealing" in aquafarms, causing them to exhibit less tolerance to human disturbance. Our study increases understanding of the behavioral response patterns of herons in human-wildlife conflicts and provides valuable insights for more scientific and rational management and protection of Ardeidae species.

Phytogenic Feed Additives as a Sustainable Alternative to Antibiotics: Enhancing Growth and Disease Resistance in Nile Tilapia (Oreochromis niloticus)

Pathogens and challenging conditions in fish farming are common problems that cause mortality and reduce growth performance. Phytogenic feed additives can support the immunity of fish and thereby improve performance, production, and disease resistance. Two experiments with Nile Tilapia aimed to evaluate the effects of a matrix-encapsulated phytogenic additive (Digestarom® P.E.P. MGE) in different feed formulations, which vary in the marine meal inclusion level (5% and 12.8%), on growth performance and resistance against Streptococcus agalactiae. Fish were stocked in a recirculating aquaculture tank system per experiment and were fed with diets with or without the phytogenic supplementation for 8 weeks (six replicates per group). After an intraperitoneal injection with a sterilized saline solution and bath immersion with S. agalactiae (5 × 106 CFU/mL), mortality of the fish was recorded for 20 days. Independent of the diet formulation, the supplementation with the phytogenic feed additive significantly improved the fish production; feed conversion ratio; immune response (mainly lactic acid dehydrogenase, differential blood cell counts, and the lysozyme activity in blood); and fish survival after the S. agalactiae challenge. Thus, phytogenic feed additives are promising strategies to improve Nile tilapia production by enhancing fish growth performance, health, and protection against S. agalactiae infections.

Pivotal Roles of Fish Nutrition and Feeding: Recent Advances and Future Outlook for Brazilian Fish Farming

The aquafeed industry evolved alongside fish farming, utilizing scientific and technological advancements to incorporate a variety of feed additives, supplements, and alternative ingredients in the nutrition and feeding of fish in aquaculture. These advances played a significant role in improving the production, health, and welfare of farmed fish. Recent research in Brazil highlighted the importance of using fish feed additives, such as vitamins, minerals, and amino acids, to ensure that farmed fish receive all the necessary nutrients for growth and health. Functional additives can enhance the immune system, boosting disease resistance and promoting the overall health of fish. Antimicrobial and antiparasitic additives help prevent and treat infections and infestations, reducing the occurrence of disease outbreaks. Additionally, some additives improve feed digestibility, leading to better nutrient absorption and reduced feed requirements. Overall, nutritional strategies are essential for optimizing fish farming practices in Brazil and globally, promoting fish health and sustainability in the industry. This review emphasizes the significance of certain additives, supplements, and ingredients strategically incorporated into experimental feeds for research in Brazilian fish farming. It also underscores the necessity for ongoing research. There is a noticeable trend towards developing more sustainable and efficient feeds, which is essential for the future of sustainable aquaculture. The goal is to minimize environmental impacts while maintaining economic viability in aquaculture operations.

Strategic Competency and Growth of Aquaculture-Based Small Enterprises in Kenya

Purpose: This study evaluated the role of strategic competency on growth of aquaculture based small enterprises in Kenya. Methodology: The study adopted descriptive research design using mixed methods approach. The target population was 600 fish farmers in Nyeri County, Kenya. The study utilized purposive sampling to select fish farmers within Nyeri County, then cluster sampling to identify fish farmers in their various sub-counties. Simple random sampling was then utilized to select respondents for the study. A self-administered questionnaire was used to collect data from the respondents. A pilot study was conducted to test validity and reliability of the questionnaire. Data analysis was done using Statistical package for Social Scientists (SPSS). Regression analysis and chi-square were used to test for significant associations between the dependent and independent variables. The findings were presented in frequency tables, pie charts, bar graphs and scatter diagrams in the final report. Findings: The findings indicated a positive statistically significant relationship on strategic competency and its effect on growth. Further, regression analysis of the results established that strategic competency was found to account for 5.8% of the variation in the growth of aquaculture-based small enterprises in Kenya. 94.2% of variation in the growth of aquaculture based small enterprises in Kenya is explained by other factors outside the model. Unique Contribution to Theory, Practice and Policy: Based on the study findings, the sector should sustain government and NGO support by subsidizing input costs, promoting cottage industries, and employing trained extension officers. In addition, the management should facilitate knowledge sharing through farmer excursions and disseminate information on region-specific fish farming techniques. Lastly, it should develop public-private partnerships to coordinate markets and reduce post-harvest losses through a demand-driven approach.

ДИНАМИКА РОСТА МОЛОДИ ПРЕСНОВОДНОЙ ФОРМЫ АРКТИЧЕСКОГО ГОЛЬЦА SALVELINUS ALPINUS (L.) В УСЛОВИЯХ ИНДУСТРИАЛЬНОГО РЫБОВОДНОГО ХОЗЯЙСТВА

The purpose of research is to study the growth dynamics of juvenile freshwater Arctic char in the conditions of an industrial fish farm. Objectives: to study rearing conditions, dynamics of weight, body length and safety of juveniles when fed with trout food. The object of the study was juveniles of the freshwater form of Arctic char Salvelinus alpinus (L.) of the Taimyr Peninsula, generation 2022 (n = 2892), obtained at the industrial farm of Maltat LLC. The study was carried out in a 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. The work was carried out according to the method of growing salmon fish using a combined method. Observations of the growth of char were carried out in January–August 2023. The fish were placed in a pontoon cage in the downstream of the Krasnoyarsk hydroelectric power station at a distance of 0.8 km from the dam. The depth of the cage is 4 m, the area is 36 m2. Feeding was carried out with trout feed from the Coppens company: Coppens PRE GROWER-18 2.00 mm for fish weighing up to 25 g. The amount of feed received by the juveniles was 1.5 % of the weight of the fish. Control catches were carried out monthly; the weight of at least 25 specimens was determined by random sampling. When reared in cages, the char grew intensively in the spring and summer, and by September the weight of the fry was 51.8 g and the length was 160 ± 3.59 mm. The survival rate of juveniles when fed with trout food was more than 92% throughout the entire study period.

Prevailing Knowledge on Aquaculture of Abalone in Southeast Asia: A Review

Abalone is a marine gastropod mollusc with significant economic importance in global fisheries and aquaculture. Currently, the abalone culture is actively engaged in Southeast Asia and has gained significant popularity among aquaculturists and aquafarmers in Indonesia, the Philippines, Thailand, Vietnam, and Malaysia. Abalone also has emerged as a highly profitable source of income for fish farmers in Asian countries. The exquisite taste of abalone has made it a sought-after delicacy, particularly in Chinese cuisine. However, scanty documentation of this marine gastropod has been reported on the development of aquaculture production in Southeast Asia. Therefore, to help bridge the gap, this review emphasised the information and collated ideas on the industrial culture of abalone in Southeast Asia. In this review paper, all issues on abalone culture will be summarised and highlighted, especially on the aquaculture industries of abalone, challenges and constraints in developing the aquaculture of Haliotis spp., and biological features of the abalone. This review paper could be a valuable reference for abalone aquaculture practices in Southeast Asia, with the aim of boosting production and conservation efforts of these marine gastropod molluscs, thereby benefiting abalone aqua farmers in Southeast Asian countries.

Good Agricultural Practices in Catfish Farming Among Commercial Fish Farmers in Yenagoa Local Government Area, Bayelsa State, Nigeria

This study was on Good Agricultural Practices (GAPs) in catfish farming among commercial fish farmers in Yenagoa Local Government Area (YELGA), Bayelsa state, Nigeria. The objectives were to; ascertain the awareness of GAPs among commercial fish farmers in YELGA, identify GAPs aware of by YELGA commercial fish farmers and determine the GAPs use by commercial fish farmers in catfish farming. A total of 77 fish farmers; randomly chosen from list obtained from Ministry of Trade and Industry, formed the sample size; whom structured questionnaire was administered on. Data were analysed descriptively with percentage and ranking. Findings were that; YELGA fish farmers’ percentage level of awareness of GAPs was incredible; with all the commercial fish farmers (100%) aware of GAPs, and all identified GAPs (100%) aware of by varying percentages of the commercial fish farmers. Similarly, GAPs implementation/use in catfish farming among fish farmers in YELGA was awe with high percentages of above 50% recorded for approximately 94% of GAPs identified. The study concludes that YELGA fish farmers are compliant to the global GAPs standard; being highly aware of GAPs and use/implement GAPs in catfish farming, thus are producing catfishes that will pass global standard tests and stand competition at global market places. Intensified advocacy and farmer engagement by state actors such as extension agency, and policy directive from the government for credit to farmers was recommended to ensure GAPs compliance; for fish welfare, staff/human safety and overall sustenance of GAPs among commercial farmers in the state.

Commitment Competency and Growth of Aquaculture-Based Small Enterprises in Kenya

Purpose: This study evaluated the influence of commitment competency on growth of small enterprises in Kenya. Methodology: The study adopted descriptive research design using mixed methods approach. The target population was 600 fish farmers in Nyeri County, Kenya. The study utilized purposive sampling to select fish farmers within Nyeri County, then cluster sampling to identify fish farmers in their various sub-counties. Simple random sampling was then utilized to select respondents for the study. A self-administered questionnaire was used to collect data from the respondents. A pilot study was conducted to test validity and reliability of the questionnaire. Data analysis was done using Statistical package for Social Scientists (SPSS). Regression analysis and chi-square were used to test for significant associations between the dependent and independent variables. The findings were presented in frequency tables, pie charts, bar graphs and scatter diagrams in the final report. Findings: The findings indicated that commitment competency and growth had weak inverse linear statistical relationship. The study concluded that fish farmers are already aware of the many hurdles involved in fish farming but they remain resilient in doing what it takes to achieve the goals set for their fish farms. It is not the lack of commitment on their part that contributes to the stagnating or declining of their businesses. Instead, other challenges such as lack of crucial inputs such as reliable and quality feeds, quality fingerlings, adequate water, lack of business management knowledge, lack of market accessibility and capital contribute to the dismal performance of their businesses. Unique Contribution to Theory, Practice and Policy: The government and NGOs should provide subsidized inputs and promote cottage industries to enhance aquaculture value chains. In addition, extension officers should be equipped with resources like water testing kits, and water harvesting should be encouraged in water-scarce areas.

The effect of the genotype of holstein bulls on the phosphorus content in the liver of descendants

Russian and foreign scientists continue to systematize knowledge about the accumulation of macroand microelements in the body of animals, as their study remains an urgent topic for many studies. Questions about the hereditary determination of the level of macroand microelements in animal organs and tissues are also being studied. Currently, articles by Russian and foreign authors contain separate, disparate information about the macroand microelement status of farm animals and fish of different species. Our article describes data on the phosphorus content in the liver of offspring obtained from producing bulls of the Holstein breed. The research was conducted in Kuzbass. The studied animals were in the same conditions of maintenance and feeding. The groups were formed according to the principle of analogues. The same feeding and maintenance conditions were created for the experimental animals. In the animal breeding area, the content of macroand microelements in soil, water and feed was determined, the level of heavy metals was within acceptable concentrations. The phosphorus content in the liver was determined by atomic emission spectrometry on the ICP AES IRIS device. The phosphorus level in the offspring of the sons of different Holstein bulls was in the range of 2964–3417 mg/kg. In the liver of the descendants of some bulls, the phosphorus content was 1.15 times higher than in others. The index of the strength of the influence (RW) of fathers on the phosphorus content in the liver of sons was 0,49 (p &lt; 0.05). This indicates the influence of the genotype of fathers on the phosphorus content in the liver of descendants. The level of phenotypic variability of phosphorus concentration in the liver of offspring of different bulls was in the range of 5.6–11.6 %. The obtained average values of phosphorus levels can be taken as the physiological norm for animals of the Holstein breed in Western Siberia. The study of the level of phosphorus and other elements in organs and tissues expands the understanding of the chemical status of animals and is a characteristic of the interior.