Fish Farming Research Articles

Fish Farming Scenario in Western Santa Catarina

Objectives: This study aims to characterize and understand fish farming in the western region of Santa Catarina, offering guidance to improve fish farmers’ decision-making and identify areas for potential development. Method: The research used a qualitative approach, with data collected through semi-structured interviews with 21 fish farmers registered with the Integrated Agricultural Development Company of Santa Catarina (CIDASC), in the western region of the state. Results and Discussion: Fish farming in the western region of Santa Catarina is predominantly composed of small properties with excavated ponds, focused on tilapia production and highly dependent on family labor. Despite technological and organizational advances, there are deficiencies in technical and administrative control. These gaps indicate the need for significant improvements in the management and operation of agro-industries. Research Implications: The study suggests that specific public policies are essential for the sustainable development of the sector, including technical assistance, financial support and incentives for generational succession. These measures can help overcome challenges and foster growth in the sector. Originality/Value: This study offers a detailed analysis of fish farming in Western Santa Catarina, providing valuable information for the formulation of policies and strategies aimed at improving and sustaining the local sector.

APPLICATION FOR ANALYZING WATER QUALITY FOR TILAPIA FISH FARMING IN NET TANK

With the ability to provide food and income for the planet, fish farming and fishing, which are already widely practiced activities around the world, continue to grow across the globe. Water quality is essential for this type of activity. Controlling the chemical and physical factors of the water can ensure the success or failure of the farming. There are many ways to analyze water quality, but not all of them are simple or easy to use. The growing use of mobile devices has sought to facilitate this task, increasingly contributing to these and other activities. Aiming to support this evolution, the “Water Quality Monitor” application was modeled and developed, with the objective of providing, in a simple, easy and accessible way, relevant information on water quality scenarios for raising Nile tilapia fish in a cage-net farming environment. The application development methodology was based on the Rational Unified Process, focused on objects within programming and structured by UML diagrams. The final modeling proved capable of supporting the construction of an application to meet the expected requirements for assessing water quality, which during its use, allowed the control of chemical and physical factors of the water, ensuring the success of the creation, or indicating mitigating solutions for the corrections necessary for the process, being later validated in a case study.

Construction of Greenhouse for Horticultural Cultivation with Soil Media and Hydroponics

Theneral background greenhouse technology is increasingly recognized as an efficient solution for sustainable agricultural practices, especially in regions with limited fertile land. Specific background In Kedungpeluk Village, where the majority of residents work as fish farmers, there are also unused and arid lands. These underutilized spaces provide an opportunity for greenhouse-based horticultural cultivation using soil media and hydroponic technology. Knowledge gap however, limited knowledge and infrastructure have prevented local farmers from effectively utilizing these lands for sustainable crop production. Aims this community engagement project aims to build and utilize a greenhouse system to cultivate horticultural plants, focusing on optimizing both soil and hydroponic methods. Results the project successfully transformed barren land into productive greenhouses that facilitate the growth of tomatoes, chilies, eggplants, pak choy, and water spinach. The greenhouse structure, designed with transparent roofing, enhances sunlight exposure, promoting optimal plant growth. Both soil and hydroponic methods showed potential for increasing crop yields, with soil cultivation being more flexible but requiring extra care for pests, while hydroponics provided faster results with minimal weed and pest interference. Novelty this project introduces a dual-method approach combining traditional soil cultivation with modern hydroponic technology in a controlled greenhouse environment. Implications the findings highlight that greenhouse farming is a viable, modern agricultural solution for rural communities, offering increased productivity and quality crops, while also addressing the challenges of limited fertile land and changing climate conditions. This project serves as a model for sustainable agriculture in similar settings. Highlights: Dual-method approach: Combining soil and hydroponic techniques in a greenhouse. Efficient land use: Transforming unused arid land for productive horticulture. Controlled environment: Optimizing plant growth through sunlight, temperature, and humidity control. Keywords: Greenhouse, Horticulture, Soil Media, Hydroponics, Sustainable Agriculture

Optimal aquarium shape for rearing male Siamese fighting fish (Betta splendens)

The aggressive behavior of male Siamese fighting fish (Betta splendens) necessitates their rearing in isolation in small aquaria. For intensive production, the major concerns are growth promotion and feed utilization. The small aquaria are connected to save space but little is known about the suitable characteristics of aquaria for this species. In this study, solid-red male Siamese fighting fish (0.57–0.58 g body weight) were individually housed in aquaria that had square (SQ), rectangular (RE), equilateral triangular (ET), or right triangular (RT) cross sections. The water in the aquaria had the same depth (6 cm) and volume (180 mL). At the end of the eight-week trial, fish housed in the ET and RT aquaria exhibited superior growth rate and feed utilization to fish housed in SQ or RE aquaria (P < 0.05). No differences in morphometrics, skin coloration, muscle quality, and whole-body composition were observed. Protein- and lipid-digesting enzyme activities, as well as amylase/trypsin ratios, indicated differences in feed utilization that were correlated with aquarium shape. The findings of our study indicated that the triangular aquaria were more suitable for rearing this fish in isolation. This study could be used as an animal protocol for experimental set-up, to improve betta fish farm management, and also for the development of intensive farming systems for this species.

Green Economy Innovation in Attracting Youth to Pond Fish Farming Profession

The purpose of this study was to determine and analyze the effect of youth perceptions on interest in the fish farming profession mediated by green economy. The approach used in this research is a causal approach. The population in this study were village youth in Sungelebak, Sungegeneng Kec, Lamongan Kab. The sample in this study used simple random sampling with 100 respondents. The data collection technique in this study used a questionnaire technique. The data analysis technique in this study uses a quantitative approach using statistical analysis using the Auter Model Analysis test, Inner Model Analysis, and Hypothesis Test. Data processing in this study used the PLS (Partial Least Square) software program. The results of this study prove that directly youth perceptions and green economy have a significant effect on interest in the fish farming profession and indirectly green economy is able to mediate the effect of youth perceptions on interest in the fish farming profession. Highlights: Significant Relationships: Youth perceptions and green economy significantly influence interest in fish farming. Mediation Effect: Green economy acts as a mediator between youth perceptions and fish farming interest. Methodology: Utilized a causal approach with 100 respondents from Sungelebak village through questionnaires and PLS software. Keywords: Youth Perception, Green Economic, Interest in Fish Farming Profession

Influence of an innovative IMTA system (Mediterranean Sea, Italy) on environmental and biological parameters: Seasonal analysis

The influence of benthic suspension feeders as bioremediating organisms on water column seston and their ability to mitigate fish farm waste was assessed by monthly analyses for one year. A monthly monitoring from July 2020 to October 2021 of physico-chemical and biochemical variables of the water column and the sediment was performed in an in-shore mariculture plant located in the Mar Grande of Taranto (Italy), comparing two adjacent areas that differ in type of farming. The first (reference site) is a fish monoculture, while the second consists of an innovative Integrated Multi-Trophic Aquaculture system (IMTA site). The annual cycle of chlorophyll-a concentration showed values corresponding to mesotrophic/eutrophic conditions, with peak production in early fall (4.64 μg L−1). During the spring and summer sampling times, when the amount of aquaculture waste is greater than during the rest of the year, the reference site showed the highest lipid (151.73 μg L−1) and organic matter (189.00 mg g−1) values with respect to those at the IMTA site. The IMTA bioremediating organisms possibly acted as underwater gardens changing the seston quality and availability and providing protection and food for the zooplankton community, which showed higher abundance of individuals for most sampling times at the IMTA site, peaking during September and October in both 2020 and 2021 (max 232,985.20 ind m−3). Our results demonstrate the effectiveness of the considered IMTA system in mitigating the negative impact of organic matter release into the environment due to fish farming activities. The influence of bioremediating organisms on seston composition and concentration opened up mitigation as well as restoration scenarios.

Ultrasonography for non-invasive sex identification and reproductive assessment in Nile tilapia (Oreochromis niloticus).

Sex identification and the selection of monosex male tilapia are crucial for tilapia aquaculture. In this study, we evaluated the application of ultrasonography as an alternative procedure for sex identification and reproductive assessment in Nile tilapia (Oreochromis niloticus). Ultrasonography was performed on 23 fish weighing 232-1,281 g to capture longitudinal and transverse images of the ovaries and testes. Female tilapia were identified by the presence of numerous small egg granules and gray or light gray ovarian tissue and male tilapia by the homogeneous echogenicity and uniform gray tubular appearance of the testes. These distinct echogenic patterns allowed for accurate differentiation between the female and male fish. Ultrasonography achieved a 95% accuracy in sex identification, with minimal stress to the fish during the procedure, compared to manual sex sorting, which demonstrated an accuracy of 87%. Furthermore, the method facilitated the assessment of the reproductive status of the fish, including the maturation stages and fecundity potential. The use of ultrasonography offers significant advantages over traditional methods, such as animal welfare enhancements and improved breeding program efficiency. Our findings support the integration of ultrasonography into aquaculture practices and will promote sustainable and humane fish farming while optimizing reproductive management and productivity.

Quantitative and Weight Indicators of African Catfish Eggs and Larvae Development under Exposure to the Low-Power Ultrasound

Introduction. The growth of the world population and changing climate conditions on the planet induce the search for the innovative methods and technologies capable to increase the productivity and efficiency of the agricultural sector, and in particular — industrial fish-farming. In recent years, ultrasound has become one of such methods, widely used in many industries due to its unique properties and capabilities. In fish-farming, the use of ultrasound can significantly improve the processes of fish breeding by increasing the growth rate, improving digestion and overall health of fish, however, the issue of biostimulation of eggs and larvae with low-power ultrasound remains unexplored. The aim of this work is to study the biostimulation of eggs and larvae of African (clarias) catfish with ultrasound in aquariums as an advanced method of improving the growth and survival of this biological object at the early stages of its development, as well as a potential method for preventing the infectious and invasive diseases.Materials and Methods. The object of this study is an African clarias catfish, also known as the marbled clarias catfish (Clarias gariepinus). During the experiment, carried out at the fish-farm the “Marbled Catfish” Fish Farm” LLC (Lipetsk) from March to September 2023, 4 groups were formed — three experimental and one control. The eggs and larvae of the African catfish were exposed to the low-power ultrasound, in the experimental groups the exposure lasted for 30 s, 60 s and 120 s, respectively; the control group didn’t undergo any ultrasonic treatment. Biostimulation was carried out with a low-power submersible source of ultrasonic waves (0.243 W/cm2) and was performed 6 times. Sorting was carried out on the 15-th day from the start of incubation. In total, four series of experiment were carried out.Results. The first, second and third groups in all series of the experiment, according to sorting results, contained the largesized larvae of the African catfish in a percentage ratio of 44 to 46%; the percentage of the large-sized larvae in the control group was 19%. In terms of average-size, sorting gave the following result: in 1–3 experimental groups — from 52 to 54% of the total number of larvae; in the control one — 72%. For small-sized larvae, the following values were obtained: in groups 1–3 — from 2 to 3%, in the control group — 9% of the total number of larvae in the groups and series, respectively.Discussion and Conclusion. The growth and development of African catfish eggs and larvae are greatly influenced by the hydrological parameters of water: temperature, oxygenation, illumination, pH, hardness, content of hydrocarbonates, phosphates, nitrates and other chemical elements. In addition, fertilization of eggs may occur unevenly due to non-uniform mixing of eggs and milt, quality and maturity of eggs during fertilization, which can result in different quantitates of the catfish larvae output. The exposure of eggs and larvae to the ultrasound in the experiment resulted in an increase of a number of large-sized larvae, which is favourable for obtaining the fish seed material. Timely sorting of fish seed material before transferring an African catfish to the closed water supply systems reduces the cannibalism during further cultivation. The use of ultrasound in fish-farming requires further study to identify the optimal frequency of treatment and the effect on the commercial fish immunity and growth rate, which will foster the satisfaction of the growing needs of the population in the high-quality products of fishing industry.

Empowering Communities to Reduce Dependence on Unlicensed Mining and Minimize Corporate Losses: A Case Study of PTBA in December 2023

This study aims to analyze the impact of community empowerment programs on reducing dependence on unlicensed mining and to measure the potential losses incurred by PTBA due to these activities. The time sample used in this research is December 2023. A quantitative approach is used to calculate the income earned by the community from six empowerment programs, including bamboo downstream processing, snakehead fish farming, reclamation plant cultivation, maggot farming, quail farming, and eel farming. The total income generated by these programs for 93 beneficiaries reached USD 13,238.22 per month, with an average income per program ranging from USD 153.70 to USD 244.39, which remains below the regional minimum wage (UMR) of Muara Enim Regency, set at USD 233 per month. This income is compared to assess how competitive the alternative livelihoods provided by the empowerment programs are. In addition, this study calculates PTBA’s losses from unlicensed mining in the same month, based on the extraction of 0.175 million tons of coal, the market price of USD 58.28 per ton, and the lost royalties of 8%. The total financial loss reached USD 10.2 million, with USD 815,920 in lost royalties. The analysis underscores the importance of expanding and strengthening community empowerment programs to further reduce unlicensed mining activities, while also mitigating the financial and environmental impacts on the company.

Features of environments for cage fish farming in the Astrakhan Region on example of the Khurdun River

Features of environments for cage fish farming in the Astrakhan Region on example of the Khurdun River

Colamine and tartaric acid based innovative antioxidant and anti-spoilage food additive for fish product industry

Background: Fish farming is a vital sector of the global food industry, facing the challenge of developing efficient, chemical-free feeds for high-value fish species. To address this, innovative antimicrobials and antioxidants are crucial. This study explores the antioxidant and anti-spoilage properties of novel N-containing derivatives of natural L-tartaric acid (TA), a safe and widely used food additive. Objectives: Current research is devoted to L-tartrates’ new derivatives’ anti-spoilage and antioxidant potential as an innovative combined feed additive for fish farming. Results: TA Cyclic imide obtaining modified technology was advised. According to the obtained results, TA itself didn’t show antioxidant activity: nevertheless, in combination with new N-containing derivatives, it increased the antioxidant properties of L-ascorbic acid by about 20%. The studied TA amino-derivatives have demonstrated the emphasized activity against the fish-pathogenic Pseudomonas, Streptococcus, and other pathogenic microbes. Conclusions: TA and tartrates, in combination with new N-containing derivatives generated based on the vital compound colamine, have demonstrated several synergic antioxidant activities. They can be recommended for potential application as a cheap and effective alternative to classical anti-spoilage and preservative agents for animal feed production. Also, they showed the prolongation of feed expiration periods. It will significantly increase the quality of final fish products. A further detailed study of toxicological properties of amino derivatives is planned. Keywords: tartaric acid derivative, colamine, antimicrobial, antioxidant, anti-spoilage, feed additive

BUSINESS PLAN ANALYSIS OF HEALTHYLE

Catfish is a popular and affordable fishery product enjoyed by many. Healthyle, which stands for Healthy Lele, was established in 2023 to sell instant frozen catfish products, including ready-to-fry catfish and catfish katsu. These products are made from catfish farmed according to Good Fish Farming Practices (CBIB) and are halal certified. The catfish farming operation began in 2021. This study aims to analyzing Healthyle's marketing and operational strategies. This research uses data collection techniques carried out is secondary data. The result of this study is Healthyle's business plan highlights the need for comprehensive analysis to refine marketing and operational strategies. Despite a broad market for catfish in Jabodetabek and West Java, Healthyle’s marketing remains traditional and underutilized. The pricing is competitive, and the supply chain for raw materials is secure, suggesting that enhancing marketing efforts could significantly improve sales performance.

Water Quality Monitoring and Control System for Tilapia Cultivation Based on Internet of Things

This research analyzes the quality of water for tilapia habitat which is a type of brackish water fish that is currently widely cultivated by pond farmers. This fish is the choice because of its flexibility regarding habitat. However, despite having flexibility in terms of habitat, each harvest of tilapia that lives in a different habitat will produce tilapia with different quantity and quality. Currently, many tilapia farmers still carry out the cultivation process using traditional methods using ponds. Kuala Kerto Village, Lapang District, North Aceh is one of the locations where many tilapia fish farmers use ponds as a habitat for this fish. Not infrequently, changes in natural conditions such as rain and floods have an impact on tilapia fish ponds in this village. Thus, crop yields are very varied, often even resulting in losses. One of the reasons for this is that there is still minimal use of technology in tilapia cultivation in this village. The design of a water quality monitoring and control system for IoT-based tilapia cultivation in this research was carried out to help the problems of tilapia pond farmers. Through this research, a tool was produced in the form of a prototype IoT device that can be used to monitor and control water quality in tilapia fish ponds. This device utilizes several sensors such as turbidity sensors, ammonia sensors, salinity sensors, pH sensors, and several other sensors as data takers which will later be transmitted and displayed via a web application. Research and development of this device uses the RD method, namely research and development.

Effect of Solid-state Fermentation on Proximate Composition of Rice Bran Meal

Fish farming is often faced with high feed cost comprising approximately 60 to75% of total production costs; these causes decrease in profit margin for the fish farmers. An attempt to upsurge the profit is to minimize the cost of feed as minimal as possible. One way to do this is to explore local feed ingredients that could be used as an alternatives for fish feed. Consequently, farmers use locally available fish feed ingredients including agricultural by-products. These feed ingredients have led to increased pond productivity due to their nutrients constituent and bio-availability. This study evaluate the effect of solid state fermentation on proximate compositions of fermented rice bran meal. Rice bran was collected in three different containers, ground into powder, then sieved and fermented using solid state fermentation procedure. Each sample was solidly fermented at 10% moisture and keep in fermenter at ambient temperature for 24 hours (1 day), 96 hours (4 days), and 168 hours (7 days). Afterward, the fermented samples were oven dried for one hour at 100oC. The fermented samples were taken to the laboratory for proximate analysis. The results obtained from the study shows that, fermenting rice bran for seven days (168hrs) increases the crude protein from 10.53±1.27 to 15.07±1.43 and reduction in crude fibre from 10.74±062 to 7.87±1.71. This study revealed that, solid state fermentation of rice bran meal for one to seven days improved the crude protein and reduces crude fibre and the fermented bran meal can be incorporated as an essential part of the fish feed.

Evaluation of Praziquantel effectiveness in treating Nile tilapia clinostomid infections and its relationships to fish health and water quality

This study aimed to conduct a multidisciplinary investigation integrating detailed morphology, molecular characterization, water parameters, histopathology alteration, and the trials of treatment of Clinostomum spp. In this study, 300 Nile tilapia (Oreochromis niloticus) were collected from the farmed and wild Nile River at Al Bahr Al Aazam, Giza Governorate to assess Clinostomid infection prevalence. Fish and water samples were collected from private fish farms, and water drains at Dakahlia, and Giza, Egypt. Analysis of the water revealed inadequate water quality, particularly in the fish farms. Snails and piscivorous birds were abundant at fish collection sites. The recovered Clinostomid MCs morphological characteristics and COI gene sequence analysis identified them as Clinostomum complanatum, C. phalacrocoracis, and Euclinostomum heterostomum. Clinostomid MCs disturbed the fish’s hematological and biochemical blood parameters. Bath treatment of parasitized fish with praziquantel (2 mg/L for 24 h) revealed a significant reduction in the number of vital MCs vs. infected fish (non-treated). Praziquantel (PZQ) is an effective and safe therapy for controlling Clinostomid infections affecting farmed Nile tilapia. The current findings indicate a link between poor environmental conditions and Clinostomum infections in tilapia. The study highlights the impacts of Clinostomid MCs on fish health and recommends bath treatment with PZQ as an efficient control method for these dangerous parasites to protect human and fish health.

Prevalence of Ectoparasites in Tilapia (Oreochromis niloticus) in Sidoarjo, Indonesia

The problem most often encountered in fish farming is disease which can cause a decrease in fish production levels. Parasites cause one of the infectious diseases found in fish farming. The presence of parasites can cause a decrease in the quality of the growth of fish production. The purpose of this study was to identify the prevalence of ectoparasites on Nile tilapia in Sidoarjo, Indonesia. Ninety-six samples from two ponds were examined under the microscope to find out the presence of ectoparasite that exists in the outside body part of the fish. Samples were collected from skin, fins, tail, and gills using native methods and observed under a microscope in the Division of Parasitology Laboratory, Faculty of Veterinary Medicine, Universitas Airlangga. The results of this study showed 86 samples positively infected by ectoparasite and 10 showed negative. The ectoparasites found in this study were Trichodina sp., Chilodonella sp., Ichthyophthirius multifillis, Gyrodactylus sp., and Dactylogyrus sp. The highest prevalence is Trichodina sp. and Dactylogyrus sp. The number of fish infested by ectoparasite is 89.56%, this is classified in the usual category. The highest prevalence occurs in infestations of Trichodina sp. i.e.72.91% which were contained in the 70 samples. While the lowest prevalence was in Gyrodactylus sp. by 8.32% in 8 fish samples. Double infections from two different ponds were 70% within 33 samples which were included in the usual category.

Curcumin attenuates ochratoxin A and hypoxia co-induced liver injury in grass carp (Ctenopharyngodon idella) by dual targeting endoplasmic reticulum stress and apoptosis via reducing ROS content

BackgroundOchratoxin A (OTA) is a toxin widely found in aquafeed ingredients, and hypoxia is a common problem in fish farming. In practice, aquatic animals tend to be more sensitive to hypoxia while feeds are contaminated with OTA, but no studies exist in this area. This research investigated the multiple biotoxicities of OTA and hypoxia combined on the liver of grass carp and explored the mitigating effect of curcumin (CUR).MethodsA total of 720 healthy juvenile grass carp (11.06 ± 0.05 g) were selected and assigned randomly to 4 experimental groups: control group (without OTA and CUR), 1.2 mg/kg OTA group, 400 mg/kg CUR group, and 1.2 mg/kg OTA + 400 mg/kg CUR group with three replicates each for 60 d. Subsequently, 32 fish were selected, divided into normoxia (18 fish) and hypoxia (18 fish) groups, and subjected to hypoxia stress for 96 h.ResultsCUR can attenuate histopathological damage caused by coming to OTA and hypoxia by reducing vacuolation and nuclear excursion. The alleviation of this damage was associated with the attenuation of apoptosis in the mitochondrial pathway by decreasing the expression of the pro-apoptotic proteins Caspase 3, 8, 9, Bax, and Apaf1 while increasing the expression of the anti-apoptotic protein Bcl-2, and attenuation of endoplasmic reticulum stress (ERS) by reducing Grp78 expression and chop levels. This may be attributed to the fact that the addition of CUR increased the levels of catalase (CAT) and glutathione reductase (GSH), increased antioxidant capacity, and ensured the proper functioning of respiratory chain complexes I and II, which in turn reduced the high production of reactive oxygen species (ROS), thus alleviating apoptosis and ERS.ConclusionsIn conclusion, our data demonstrate the effectiveness of CUR in attenuating liver injury caused by the combination of OTA and hypoxia. This study confirms the feasibility and efficacy of adding natural products to mitigate toxic damage to aquatic animals.

New perspectives on metagenomic analysis for pathogen monitoring in sustainable freshwater aquaculture production: a systematic review

The freshwater and saltwater aquatic food sector has experienced the most significant growth in recent years and is increasingly recognized as a sustainable alternative for fostering prosperous societies self-sufficiently and ecologically. One primary economic and health risk factor in aquaculture production is health control, with potentially more severe impacts observed in tropical and developing countries. While metagenomics holds great promise for application in agro-industrial fields like aquaculture, its adoption remains limited. Consequently, this study aimed to assess the prospects for developing and applying metagenomics in identifying pathogens in freshwater aquaculture. The WIPO database was used to search for patents developed using metagenomics to monitoring pathogens in freshwater aquaculture. Metagenomics methods have been extensively employed in different fields, such as, medicine, veterinary, biotechnology, agriculture, particularly in studies focusing on microbial communities in different ecosystems. In aquaculture, the utilization of metagenomics has predominantly revolved around investigating antibiotic resistance genes, primarily in saltwater farms. Despite this, freshwater aquaculture, particularly in fish and crustacean farming, aligns closely with sustainable development goals, notably (SDGs) 2, 3, 6, and 13. Countries such as the United States of America, South Korea, and Canada stand at the forefront of utilizing metagenomics for disease monitoring in freshwater aquaculture, evidenced by their active patent developments. The metagenomic analysis, coupled with bioinformatics tools and databases, represents a rapid, secure, and non-invasive approach to environmental monitoring for preventive purposes.Systematic review registrationhttps://osf.io/srpyz/, identifier 10.17605/OSF.IO/SRPYZ.

Specific amino acid changes correlate with pathogenic flavobacteria.

Flavobacterium is a genus of microorganisms living in a variety of hosts and habitats across the globe. Some species are found in fish organs, and only a few, such as Flavobacteriumpsychrophilum and Flavobacterium columnare, cause severe disease and losses in fish farms. The evolution of flavobacteria that are pathogenic to fish is unknown, and the protein changes accountable for the selection of their colonization to fish have yet to be determined. A phylogenetic tree was constructed with the complete genomic sequences of 208 species of the Flavobacterium genus using 861 softcore genes. This phylogenetic analysis revealed clade CII comprising nine species, including five pathogenic species, and containing the most species that colonize fish. Thirteen specific amino acid changes were found to be conserved across 11 proteins within the CII clade compared with other clades, and these proteins were enriched in functions related to replication, recombination, and repair. Several of these proteins are known to be involved in pathogenicity and fitness adaptation in other bacteria. Some of the observed amino acid changes can be explained by preferential selection for certain codons and tRNA frequency. These results could help explain how species belonging to the CII clade adapt to fish environments.

Bacillus Sp. as Potential Probiotics for Use in Tilapia Fish Farming Aquaculture – A Review

Abstract Aquaculture is a crucial and rapidly expanding industry in global food production. Fisheries are also an essential socio-economic activity, providing abundant resources and remarkable prospects. However, due to the deteriorating ecological environment, aquatic animals are often exposed to traumatic conditions and are susceptible to bacterial infections that pose significant challenges for aquaculture production. The indiscriminate use of antibiotics in the past has led to the emergence of multidrug-resistant pathogens and sudden outbreaks of infectious diseases, resulting in serious economic losses. Moreover, the use of expensive chemotherapeutic drugs and antibiotics has negative impacts on aquatic environments. Therefore, it is increasingly important to adopt alternative natural agents, such as probiotics and their metabolites, to enhance healthy fish production. Probiotics are microorganisms that have numerous beneficial effects on their hosts. They are environmentally friendly, non-toxic, and cost-effective. This review specifically focuses on the use of Bacillus sp. as probiotics to promote healthy tilapia production in the aquatic sector, while also examining their interactions with the immune system and gut micro-biota. The information presented in this review can guide future research and promote effective and healthy tilapia culture production.