Betta Research Articles

Effects of Crab Shell Waste as Feed on Growth Performance and Colouration of Siamese Fighting Fish (Betta splendens)

Betta splendens, Siamese fighting fish exhibit behavior, coloration, and morphology that make them popular aquarium fish in aquaculture. Coloration for this fish requires high-quality feeds rich in carotenoids. Crab shells, mostly dumped as agro-waste by the seafood industry contain carotenoids and protein that can be an alternative for carotenoids in fish feed. The objectives of this study were to analyze the proximate composition and carotenoid content in feed and determine the effect of crab shells as feedstuff on the growth performance and coloration of Betta splendens. A 40-day feeding trial using 45 tails of B. splendens with an average body weight, of 0.25 g was conducted by using five feed treatments namely TC (0% crab shell), T1 (25% crab shell), T2 (50% crab shell), T3 (75% crab shell) and T4 (100% crab shell) respectively. Sampling was done weekly. Analysis done were proximate composition and extraction of carotenoid while growth performance parameters such as body weight gain (BWG), specific growth rate (SGR), feed intake (FI), and feed conversion ratio (FCR) were also taken. Skin coloration and water quality data were collected every 10 days. All data were analyzed using One-Way ANOVA via SPSS. Results showed protein content for T1 (22.40±0.29) was slightly higher compared to all treatments. Carotenoid content in crab shells was lower compared to krill. Body weight from T1 (25% crab shell) showed a significant increase among all treatments. All treatments show no changes in coloration. In conclusion, T1 (25% crab shell waste) is the best treatment as it has a high protein content that improves body weight gain without any significant effect on coloration in all treatments.

The Effect of Different Photoperiods on The Oogenesis of Fighting Fish (Betta Splendens)

The demand for fighting fish Betta splendens continues to increase every year, this encourages farmers to develop technology in the production process. Accelerating reproduction is one solution to support production demand. One technology prior to this is photoperiod. The aim of this research was to evaluate different photoperiod treatments on the stages of betta fish ovarian development. The method used is completely randomized design (CRD) to test 3 different treatments in quintuplicates. Treatment P1 (10-h Light L :14-h Dark D), P2 (14-h L :10-h Dark D), and P3 (Control, ambient lights). Observation of the oogenesis stages of betta fish was carried out through histological preparations classic and calculating the proportions of oogenesis stages. Data were then analyzed statistically (ANOVA) with 0.05 level. The research results showed that treatment P2 was significantly different from P1 and P3, due to domination of previtellogenic oocytes (22.05%), oocyte exogenous vitellogenin (22.89%), and hydrated vitellogenin oocytes (25.24%). Then followed by treatment P1 (10L; 14D) presented previtellogenic oocytes ​​(20.86%), exogenous vitellogenin oocyte (20.17%), and hydrated vitellogenin oocytes (21.82%). In Control, ovaria contained previtellogenic oocytes (19.43%), exogenous vitellogenin oocytes (18.79%), and hydrated vitellogenin oocytes (19.21%). This indicated that under such photoperiod treatments fish kept on adept to develop their ovaria. Moreover, fish matured their ovaria and were apt to spawn.

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

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

Using ozone nanobubbles to mitigate the risk of mycobacteriosis in Siamese fighting fish (Betta splendens)

Betta splendens, a valuable ornamental fish species, is particularly susceptible to mycobacteriosis which poses a challenge to the sustainability of its culture and trade. Since there are no effective treatments for the disease, betta fish farms must take rigorous preventive measures. This study investigated the efficacy of ozone nanobubbles (NB-O3) to disinfect water for mitigating the risk of mycobacteriosis in betta fish. Laboratory tests showed a significant disinfecting effect of NB-O3 against a highly pathogenic, multidrug-resistant strain of Mycobacterium chelonae by destroying bacterial cells. After incubation in NB-O3 water for 60 min, the concentration of M. chelonae in distilled water was reduced by 96.71 to 99.92%. In practice, treatment of reserved and cultured water from betta farms with direct NB-O3 for a single 10 min significantly reduced total bacterial counts and presumptive mycobacteria by over 90%. In experimental infection, sub-adult betta fish (2-month-old) cultured for 14 days in water spiked with M. chelonae (∼106 CFU/mL), which served as a positive control group, had a low percent survival of 38.33%. In contrast, fish reared in the same water as the positive control group but treated with NB-O3 three times for 10 min at 20 min intervals had a significantly higher percent survival of 93.93%. Moreover, the relative percent survival (RPS) of the treatment group showed a statistically significant difference, with an RPS of 89.19% compared to only 67.57% in the negative control group (neither exposure to M. chelonae nor treatment with NB-O3). In conclusion, this study demonstrated that NB-O3 effectively reduces bacterial concentrations in water, mitigates the risk of mycobacteriosis, and enhances the survivability of betta fish exposed to multidrug-resistant M. chelonae. This non-chemical and non-antibiotic approach offers a promising solution for disease control in the betta fish industry.

Acute toxicity of ammonia and nitrite to Siamese fighting fish (Betta splendens)

The acute toxicity and sublethal effects of ammonia and nitrite on the air-beathing Siamese fighting fish, betta (Betta splendens) was studied for 96 h. The LC50 (50% Lethal Concentration) for 96 h for adult bettas to ammonia-N and nitrite-N was 123.4 mM (1.7 g/L, 95% confidence limits: 114.7–130.0 mM) and 24.6 mM (343.6 mg/L, 95% confidence limits: 22.7–26.4 mM) respectively. Exposure to 90 mM ammonia did not affect ammonia and urea excretion rates in bettas. There was no significant difference in values between control and ammonia-loaded (90 mM ammonia) individuals in either brain or liver activities of glutamine synthase, while plasma ammonia levels slightly increased. It appears unlikely that ammonia was converted to urea or amino acids for detoxification. Sublethal nitrite (24.6 mM nitrite) affected plasma nitrite, methemoglobin and hemoglobin. Plasma nitrite values remained much lower than ambient concentrations. Betta has a labyrinth organ and can breathe air. Bettas may temporarily reduce the entry of ammonia and nitrite into the body by increasing the rate of air respiration and reducing the contribution of the gill epithelium, which is highly permeable to these nitrogenous pollutants.

IoT Based Smart Betta Fish Monitoring system with fish fatality prediction.

This study enlightens the importance of rearing water quality to Betta fish health. A water quality monitoring system was developed based on water quality parameters namely water pH, temperature (°C) and TDS level (ppm). Fuzzy Logic Algorithm was applied to predict the possibility of the fish to get infected by the disease using combination of the water quality parameters value. Graphical User Interface (GUI) was developed to test the efficiency of the fish disease prediction system using fuzzy logic algorithm before the fuzzy rule been embedded to the IOT system. Arduino Uno Wi-Fi R2.0 and Blynk Apps used for enabling the system to update the aquarium water quality to owner in real-time. Hydroponic technology implemented in this project for recirculate rearing water inside the fish tank. Theoretically, the aquaponic system will help regulate the water tank parameters in optimum range and Betta Splendens should be free from all diseases.

Anesthetic effect and acute toxicity of Citrus sinensis essential oil in betta

This study investigated the use of Citrus sinensis essential oil (EOCS) in Betta splendens, evaluating toxicity, induction and recovery times to anesthesia, its action on agonist behavior, and on male collective transport. To toxicity, fish were exposed to EOCS at different concentrations during 48 h. The induction test was performed to evaluate sedation, anesthesia, and recovery under different concentrations. To assess agonist behavior, male subjects were maintained with different dosages of EOCS, assessing opercular beat and fin expansion, while exposed to untreated animals. In the mass transport study, males were divided into two treatments with two levels of EOCS, for 6 h, also analyzing gill histometry at the end of transport. The results obtained show that the mean lethal concentration in 48 h of exposure to EOCS was calculated at 49.17 μL·L−1. The shortest anesthesia induction time was at 300 μL·L−1 EOCS. EOCS was able to reduce agonist behavior in males individual. Histometric analyzes revealed a reduction in the height of gill filaments in fish transported with 20 μL·L-1 EOCS. EOCS can be used as a sedative and anesthetic agent for B. splendens.

Dietary Spirulina platensis to Increase Color Brightness and Growth of Betta Fish, Betta splendens

Betta fish (Betta splendens) are ornamental fish that have a unique color and high economic value. The aim of this research was to evaluate the addition of different doses of S. platensis in feed on color brightness and growth of betta fish. Betta fish (length of 32±4.4 mm) were maintained in containers with a volume of 4 liters at a density of 1 fish/container for 35 days and feeding is done twice a day at satiation. This research consisted of 4 treatments adding different doses of S. platensis in the feed and 5 repetitions, namely: P1: adding S. platensis 0%, P2: adding S. platensis 1%, P3: adding S. platensis 1.5%, and P4: addition of S. platensis 2%. The research results showed that the carotenoids contained in S. platensis are 737.16 ppm/50 g. The addition of S. platensis in feed can improve the color quality of betta fish but does not affect the growth of betta fish. The addition of 1.5% S. platensis in the feed produced the highest values in the parameters of color brightness (9.1 in the 4th week), color diversity (body 62.54%, base of tail 59.52% and tail 61 .22%), and chromatophore cell area (673000 µm2).

Infection and histopathological consequences in Siamese fighting fish (Betta splendens) due to exposure to a pathogenic Mycobacterium chelonae via different routes

Mycobacteriosis, a chronic progressive disease in fish caused by Mycobacterium spp., is typically characterized by granulomatous lesions that illustrate its harmful pathogenesis. This study was initiated to understand the progression of mycobacteriosis in Siamese fighting fish (Betta splendens) through various transmission modes. Experimental infections were conducted using a pathogenic isolate of Mycobacterium chelonae originally derived from a naturally infected betta fish. The bacteria were administered by five different routes at three doses (approximately 105, 106, 107 CFU/fish or CFU/mL), including intraperitoneal (IP) and intramuscular (IM) injections, oral administration, immersion, and immersion with skin trauma. Acute infections, typified by short survival, non-specific gross signs, and severe organ necrosis, were frequently observed in the IP and IM methods. The median lethal dose (LD50) for these methods was 4.16 × 105 CFU/fish and 1.66 × 106 CFU/fish, respectively, within seven days following infection. Conversely, oral administration and immersion with or without skin trauma resulted in negligible fish mortality but triggered progressive chronic disease. Chronically infected fish survived the 28-day trial but exhibited macroscopic pathology such as emaciation, aesthetic deterioration, along with an increased presence of melanomacrophage centers (MMCs) in lymphoid tissues and/or systemic granulomas, as noted in histopathology. The results indicate that the course of M. chelonae infection is strongly correlated with the exposure routes, with injuries on the fish body and/or via the digestive tract being the most probable natural pathways. This study expands the understanding of the pathogenesis of Mycobacterium species in betta fish and emphasizes the need to mitigate risk factors associated with exposure routes to effectively control the disease.

Predatory Efficiency of Larvivorous Fish against Mosquito Larvae in Different Water Temperature Levels: Implication in Control Measure of Dengue Vector.

Reduction of the Aedes aegypti population is the priority effort to control dengue virus transmission including the use of larvivorous fish. Biologically, the predatory efficiency of fish will slow down when the water acidity and temperature change from normal conditions. This study aimed to determine the predatory efficiency of three species of larvivorous fish against the Ae. aegypti larvae in different water temperatures. Three well-known species of larvivorous fish namely Poecilia reticulata, Betta splendens, and Aplocheilus panchax were placed into 12 cm diameter jars with three water temperature ranges namely 20-21 °C, 27-28 °C, and 34-35 °C, and allowed to three days acclimatization. As many as one hundred 4th-instars larvae of Ae. aegypti were gradually entered into each jar, and a longitudinal observation was made at 5, 10, 30, 60, 120, 240, 360, 480, 600, and 720 minutes. The predated larvae were recorded. In normal temperature ranges, the predatory efficiency of the larvivorous fish was 75%, 72.3%, and 32.8% for B. splendens. Aplocheilus panchax, and P. reticulata, respectively. The predation abilities decreased due to temperature changes. Betta splendens and A. panchax indicated the best predatory efficiency against Ae. aegypti larvae in different temperature conditions. Betta splendens is the best larvivorous fish in the lower to normal, but A. panchax is the best in the normal to higher temperature ranges. This finding should be considered by public health workers in selecting larvivorous fish to control the Dengue vectors.

Fermented water of Thai herbs effectively enhanced amputated fin regeneration in Siamese fighting fish (Betta splendens)

The aggression of Siamese fighting fish (Betta splendens) during courtship and reproductive behaviors can result in torn fins. However, the natural regeneration of torn fins has been significantly improved by treating fish with fermented water of plants. We amputated half of the caudal fin of male Siamese fighting fish (1.29 ± 0.01 g body weight) in the vertical plane. The amputated fish were individually reared in fermented water containing eight combinations of herbs that included dried Indian almond (Terminalia catappa) leaf (IAL, 0.25 g L−1), dried banana (Musa sapientum) leaf (BL, 1.5 g L−1), and dried papaya (Carica papaya) leaf (PL, 2.5 g L−1) as major ingredients. Other ingredients included dried lemongrass (Cymbopogon citratus) leaf (LL, 1 g L−1), dried clay (50 g L−1), and salt (5 g L−1). For comparison, other fish were reared in non-fermented water. The experiment was conducted in a completely randomized design for five weeks, comprising fifteen fish per treatment. Individual fish served as experimental units. Fin regeneration was monitored weekly while growth performance was recorded at the end of the trial. The herbal treatments had no effects on growth, body morphometrics, and feed utilization (P > 0.05). However, fin regeneration was statistically improved for the fish reared in combinations of IAL, BL, and PL (P < 0.05). Among these alternative treatments, red color intensity was fully redeveloped in fish reared in three herbal treatments (P < 0.05) that all contained dried papaya leaf (BL + PL, IAL + PL, and IAL + BL + PL). Therefore, those three treatments effectively enhanced fin regeneration.

Evaluation of yellow pumpkin seed extract (Cucurbita moschata D) on the successful masculinization of betta fish (Betta splendens)

Betta fish is one of the most popular freshwater ornamental fish. This ornamental fish is very popular among people of various ages because it is easy to maintain. However, fans of these ornamental fish prefer male fish over females because male fish have aesthetic values and better and attractive colors and have higher profits. The experiment aims to determine the effect of yellow pumpkin seed extract on the successful of male betta fish larvae, as well as giving the best dose. The design used was a completely randomized design (CRD) with 4 treatments and 3 replications. The immersion doses used were control A, treatment B with a dose of 40 mg/L, treatment C with a dose of 80 mg/L and treatment D with a dose of 120 mg/L. Maintenance period for 30 days. The results showed that soaking using yellow pumpkin seed extract with different concentrations had a very significant effect on the percentage of males. The percentage of male betta fish ranged from 40.00–90.00%, the percentage of female betta fish ranged from 5.00–45.00%, and the percentage of intersex betta fish ranged from 5.00–15.00%. The best concentration of yellow pumpkin seed extract was 120 mg/L with the percentage of male betta fish 90.00% in treatment D.Keywords: Betta splendens Larvae; Immersion; Maleization; Pumpkin Seed Extract

Marketing Analysis of Betta Fish (Betta sp.) Cultivation in Semarang City

Semarang city is one of the cities in Indonesia which has quite developed ornamental fish potential, one of which is betta fish (Betta sp.). Betta fish or Betta sp (Betta splendens) is an ornamental fish commodity that is well known among Indonesian people. The characteristics of this ornamental fish it has a beautiful color and a tail fin that is long and also wide with a variety of shapes. Apart from its beauty, betta fish are easy to cultivate and can be a profitable business prospect. The aims of this research are to identify the marketing flow, marketing margin, and farmer’s share of betta fish cultivation in Semarang City. The method used in this study is a qualitative method with descriptive analysis. The data analyzed are marketing flow, marketing margin, and farmer’s share. Respondents were determined using 2 methods, namely purposive sampling, and snowball. The number of respondents were 5 people with details of 3 fish farmers, 1 trader, and 1 retailer. The results showed that there were 3 marketing channels for betta fish farming in Semarang city, from the three channels it was found that the most efficient marketing channel was marketing channel III with a marketing margin of 0 and a farmer’s share value of 100%.

Quantifying the Neural and Behavioral Correlates of Repeated Social Competition in the Fighting Fish Betta splendens

The fighting fish Betta splendens, long studied for its aggressive territorial competitions, has the potential to be a tractable and relevant model for studying the intersection of cognitive ecology and social neuroscience. Yet, few studies have comprehensively assessed Betta behavior across both social and nonsocial contexts. Furthermore, the present study is the first to quantify the expression of phosphorylated ribosomal protein S6 (PS6), a proxy for neural response, in the Betta telencephalon. Here, we assessed male Betta behavior across a suite of tasks and found that response to a mirror, but not neophilia (a novel object) nor anxiety (scototaxis), predicted behavior in a social competition. To then explore the cognitive aspects of social competition, we exposed Betta to either a familiar or novel opponent and compared their competitive behavior as well as their neural responses in the teleost homologs of the hippocampus, basolateral amygdala, and lateral septum. We did not detect any differences between familiar-exposed and novel-exposed individuals, but by implementing the first use of a habituation–dishabituation competition design in a study of Betta, we were able to observe remarkable consistency in competitive outcomes across repeated exposures. Taken together, the present study lays the groundwork for expanding the use of Betta to explore integrative and multidimensional questions of social cognition.

Genetic manipulation of betta fish.

Betta splendens, also known as Siamese fighting fish or "betta," is a freshwater fish species renowned for its astonishing morphological diversity and extreme aggressive behavior. Despite recent advances in our understanding of the genetics and neurobiology of betta, the lack of tools to manipulate their genome has hindered progress at functional and mechanistic levels. In this study, we outline the use of three genetic manipulation technologies, which we have optimized for use in betta: CRISPR/Cas9-mediated knockout, CRISPR/Cas9-mediated knockin, and Tol2-mediated transgenesis. We knocked out three genes: alkal2l, bco1l, and mitfa, and analyzed their effects on viability and pigmentation. Furthermore, we knocked in a fluorescent protein into the mitfa locus, a proof-of-principle experiment of this powerful technology in betta. Finally, we used Tol2-mediated transgenesis to create fish with ubiquitous expression of GFP, and then developed a bicistronic plasmid with heart-specific expression of a red fluorescent protein to serve as a visible marker of successful transgenesis. Our work highlights the potential for the genetic manipulation of betta, providing valuable resources for the effective use of genetic tools in this animal model.

MULTI-DIMENSIONAL SUSTAINABILITY ASSESSMENT IN MICRO-BUSINESS OF SIAMESE FIGHTING FISH CULTIVATION DURING THE COVID-19 PANDEMIC

The economic value of Siamese Fighting fish and betta fish (Betta splendens) cultivation at the micro-business level has good potential to be developed during the COVID-19 pandemic. Considering the potential of the betta ornamental fish business, not a few parties use this as an alternative solution to the community's income crisis. During the COVID-19 pandemic, many parties engaged as ornamental fish cultivators to become a commodity of economic value, which in the past was usually only fish for complaints and not specifically cultivated to become aesthetic fish. The research objective focuses on assessing multi-dimensional sustainability in micro-business Betta splendens aquaculture during the pandemic. The data collected in this study include primary data and secondary data. Primary data was collected based on a questionnaire through interviews with micro-business actors of betta fish spread across six villages community associations, while secondary data was collected based on reports, journals, and the results of relevant studies. Data analysis used multi-dimensional scaling (MDS), leverage test, and Monte Carlo test. The analysis results show that two dimensions are categorized as less sustainable, namely business feasibility and business strategy, and three other dimensions, namely market networks, infrastructure, and maintenance and handling categorized as moderately sustainable. Ten sensitive attributes are considered unstable. The conclusion of the five dimensions assessed shows a less sustainable category. Leveraging factors in each dimension can be a key to developing a sustainable strategy for micro-business siamese fighting fish farming in the future.

Community perception of biocontrol agent using Betta splendens (Ikan Cupang) against Aedes aegypti larvae: a community study in Bali

Community perception of biocontrol agent using Betta splendens (Ikan Cupang) against Aedes aegypti larvae: a community study in Bali

Insight into characteristics and pathogenicity of five rapidly growing non-tuberculous Mycobacterium species isolated from the Siamese fighting fish, Betta splendens

Siamese fighting fish (Betta splendens) play an important role in the global aquarium trade, but their susceptibility to mycobacteriosis could challenge the long-term sustainability of the industry. Thus, this study aimed to characterize rapidly growing non-tuberculous mycobacteria (RGM) isolated from the fish and to investigate their pathogenicity. Five RGM species were investigated, namely Mycobacterium chelonae, M. cosmeticum, M. farcinogenes, M. mucogenicum, and M. senegalense. The isolates were phenotypically and biochemically characterized and assessed for susceptibility to 18 antibiotics and five disinfectants. The pathogenicity of the isolated bacteria was evaluated through experimental infection of the fish by intraperitoneal injection. The results of phenotypic and biochemical typing allowed the identification of some of the isolates and provided preliminary information to distinguish between the bacteria. All isolates were resistant to at least four antibiotics, with multiple antibiotic resistance indexes ranging from 0.22 to 0.61, with M. chelonae having the highest value. Four disinfectants (i.e., ethanol, formalin, chlorine, and povidone‑iodine) showed strong antibacterial activity, whereas potassium permanganate proved less effective. An LD50 value within 7 days showed that M. chelonae had the highest virulence at 7.12 × 105 CFU/fish, followed by M. mucogenicum at 4.25 × 106 CFU/fish and a range of 1.01–1.65 × 107 CFU/fish for the other isolates. Depending on the dose and the isolate administered, some fish displayed acute disease symptoms, while others developed a chronic condition. The acute disease was characterized by short median survival, severe peritonitis, and tissue necrosis. Fish with a chronic infection survived the 42-day trial but were emaciated and had systemic granulomas within their viscera. The findings of this study have not only improved our understanding of the nature of these RGM species but also promoted the development of control strategies to mitigate the negative impact of mycobacteriosis on the Siamese fighting fish industry.

Effect of Fish Meal Substitution with Black Soldier Fly (Hermetia illucens) on Growth Performance, Feed Stability, Blood Biochemistry, and Liver and Gut Morphology of Siamese Fighting Fish (Betta splendens)

Insects such as black soldier fly larvae (BSFL) are gaining interest among researchers and the aquafeed industry due to the fluctuating price and supply of fish meal (FM). This study evaluated the growth performance, feed stability, blood biochemistry, and liver and gut morphology of Betta splendens using BSFL as an alternative to FM. Five formulated diets were prepared: 0% BSFL, 6.5% BSFL, 13% BSFL, 19.5% BSFL, and 24.5% BSFL. The expansion rate, pellet durability index, floatability, bulk density, and water stability of the prepared feed have been assessed. Except for the diameter of the feed, all the parameters studied differed significantly ( p &lt; 0.05 ) across the experimental diets. After 60 days, the fish fed with 13% BSFL had the highest final length, final weight, net weight gain, specific growth rate, weight gain, and gastrointestinal weight, with mean and standard deviation values of 3.97 ± 0.43 cm, 3.95 ± 0.1 g, 2.78 ± 0.1 g, 4.63 ± 0.17 , 4.65 ± 0.13 , 237.26 ± 7.9 % , and 0.04 ± 0.01 mg, respectively. Similar blood haematology and biochemical properties, including corpuscular volume, lymphocytes, white blood cells, red blood cells, haematocrit, albumin, and alkaline phosphatase, were the highest ( p &lt; 0.05 ) in the 13% BSFL diet group compared to the other treatment groups. In addition, BSFL had a significant impact ( p &lt; 0.05 ) on villus length, width, and crypt depth for the anterior and posterior guts of B. splendens. The 13% BSFL diet group had an intact epithelial barrier in the goblet cell arrangement and a well-organized villus structure and tunica muscularis, compared to the other treatment groups. Furthermore, the liver cell was altered with different BSFL inclusions; the 13% FM group demonstrated better nuclei and cytoplasm structure than the other treatment groups. In conclusion, replacing 13% FM with BSFL could improve the growth performance, blood parameters, and liver and intestine morphology of B. splendens, thus providing a promising alternative diet for ornamental freshwater fish.

Transcriptome analyses of betta fish (Betta splendens) provide novel insights into fin regeneration and color-related genes

The betta fish (Betta splendens), an important ornamental fish, haswell-developed and colorful fins.After fin amputation, betta fish can easily regenerate finssimilar to the originalsin terms of structureand color. The powerful fin regeneration ability and a variety of colors in the betta fish are fascinating. However, the underlying molecular mechanisms are still not fully understood. In this study, tail fin amputation and regeneration experiments were performed on two kinds of betta fish: red and white color betta fish. Then, transcriptome analyseswere conducted to screen out fin regeneration and color-relatedgenes in betta fish. Through enrichment analyses of differentially expressed genes (DEGs), we founda series of enrichment pathways and genes related to finregeneration, including cell cycle (i.e. plcg2), TGF-beta signaling pathway (i.e. bmp6), PI3K-Akt signaling pathway (i.e. loxl2aand loxl2b), Wnt signaling pathway(i.e. lef1), gap junctions (i.e. cx43), angiogenesis (i.e. foxp1), and interferon regulatory factor (i.e. irf8). Meanwhile, some fin color-related pathways and genes were identified in betta fish, especially melanogenesis (i.e. tyr, tyrp1a, tyrp1b, and mc1r) and carotenoid color genes (i.e. pax3, pax7, sox10, and ednrba). In conclusion, this studycan not only enrich the research onfish tissue regeneration, but also has a potential significance for the aquaculture and breeding of the betta fish.