Ornamental Aquaculture Research Articles

Culture protocols of the Metallic Shiner for ornamental aquaculture

AbstractObjectiveWhile North American fishes are often overlooked by the ornamental fish industry, there is growing interest in fishes native to the southeastern USA, a hot spot for fish diversity. The Metallic Shiner Pteronotropis metallicus, a small‐bodied leuciscid native to Florida and Georgia, is sometimes available in the ornamental fish trade through wild collection and limited captive production. This species exhibits a distinctive color pattern straddling the lateral line: a dorsal pink to red line, fading to a black to blue stripe. This group of minnows is largely unknown to ornamental aquaculture and lacks defined culture protocols. Our objective was to develop culture protocols for the Metallic Shiner.MethodsFollowing collection of wild broodstock, we used routine culture methods to experimentally determine substrate preference, egg incubation, egg disinfection, larval feeding, and larval development.ResultMetallic Shiner spawning was more successful on yarn mops compared with other media, with average output of >50 embryos per tank per day. Hatching success was similar for static incubators (24%) and upwelling incubators (20%) and was also similar among egg disinfection treatments (iodine, hydrogen peroxide, and formalin). Larval feeding regimes altered survival, with Otohime A1 exhibiting higher survival (44%) over 14 days posthatch (dph) and better growth than other feeding regimes. During the developmental trial with water temperature at a relatively constant 25°C, length increased from 5 mm notochord length (4 dph) to 8.7 mm standard length (45 dph), with significant milestones occurring at 4 dph (swim bladder inflation), 16 dph (flexion), and 23 dph (hypural plate formation).ConclusionThese data provide basic culture information for the Metallic Shiner while also providing a place of reference to begin investigating culture protocols for related species, including species of conservation concern.

Understanding the captive breeding, spawning behavior and early ontogeny of Chromis viridis (Cuvier, 1830): A systematic study

The sustainability of aquarium trade relies on successful captive breeding and seed production practices to prevent the long-term consequences of wild collection, which can result in irreversible damage to natural populations. To establish comprehensive breeding and seed production protocols, it is imperative to gain a deep understanding of the reproductive characteristics of the fish, encompassing aspects such as sexual dimorphism, spawning behavior, embryogenesis, and the crucial period of larval survival. Hence, in this study, we document the captive breeding, spawning behavior, embryonic development, and early larval stages of Chromis viridis, a highly sought-after marine ornamental fish that plays a prominent role in the aquarium trade. Fish were sourced from Agatti Island, Lakshadweep, and reared in controlled conditions. Mature fish (6–9 cm) were kept in 500 L FRP tanks with regulated salinity (35.4 ± 0.5 g/L), temperature (27.1 ± 0.54 °C), and a 12-h light-dark photoperiod. After four months in captivity, spawning commenced, characterized by intense substrate cleaning and rapid swimming motions of the male. Each spawning event yielded 3562 to 20,651 eggs. Egg development included five stages over three days at 27.1 ± 0.54 °C, with hatching on the third day. Egg dimensions varied along both axes and egg volume changed over three days. Newly hatched larvae lacked eye pigments and paired fins, with an average total length (TL) of 1.97 ± 0.35 mm. Larval mouth opening occurred at 38 h, and yolk absorption was complete by the third day post-hatch. Continuous captive reproduction was observed with a spawning frequency of 5.59 ± 0.96 days. This study offers valuable insights for standardizing captive propagation techniques and advancing marine ornamental aquaculture for C. viridis by documenting its breeding, embryonic development, and early larval stages in captivity.

Developing efficient feeding and weaning protocols for Betta splendens informed by larval digestive physiology

Betta splendens, also known as the Siamese fighting fish, is an anabantoid native to Southeast Asia and is among the top ten freshwater ornamental fish species imported into the USA for the aquarium trade. Although B. splendens is a staple in the ornamental aquaculture industry, larval production continues to rely heavily on the use of Artemia spp. nauplii. Digestive physiology data can be used to minimize the use of costly live feeds during larval production by indicating when larvae can digest complex feeds like microdiets (MDs). A 30-day trial was conducted to determine the timing of the maturation of the digestive tract. Standard microplate assays were conducted to quantify pepsin, trypsin, and lipase activities and histology was used to describe digestive tract morphology. Pepsin activity and the development of gastric glands indicated the presence of a functional stomach between 15 and 18 DPH (days post-hatch). Next, a 42-day dietetics trial was conducted to determine which of three commercially available MDs best promoted growth and survival in larval B. splendens compared to an Artemia spp. reference diet. Survival was statistically similar for larvae fed Gemma Micro compared to the Artemia spp. reference diet and all MD treatments yielded significantly higher growth compared with the reference diet. Finally, a 25-day weaning trial was conducted where MD was introduced at three timepoints surrounding the development of the digestive tract. Larvae were subjected to one of five treatments: Artemia spp. reference diet, MD from first-feeding, or MD introduction at 12, 15, or 18 DPH. MD introduction at 15 and 18 DPH yielded similar survival and growth compared to the Artemia spp. reference diet. MD from first-feeding yielded statistically lower survival and growth compared to all other treatments. These results suggest that B. splendens can transition to a MD as early as 15 DPH without reducing growth or survival.

Primeiro registro do Platyfish do Sul, Xiphophorus maculatus (), (Cyprinodontiformes: Poeciliidae) em riachos costeiros da Venezuela e implicações para a conservação

Abstract Several fishes of the family Poeciliidae are commonly produced in ornamental aquaculture and also used for pest control, leading to their introduction in numerous countries. Many of these species exhibit tolerance and invasiveness, as exemplified by Xiphophorus maculatus (Günther, 1866). This report documents the presence of X. maculatus in a Caribbean coastal stream in Venezuela. Quizandal Creek has experienced significant human intervention in its lower drainage and channel area. In the final segment of the creek the fish were captured using hand nets and beach seines. The specimens were transported alive to the laboratory for evaluation and subsequently preserved according to standard methods and later were cataloged in the fish collection. 16 males ♂ and 8 females ♀ (16.6-29.4 mm SL. CPUCLA-3630) from the Quizandal Creek, part of the coastal drainage of the Borburata River, were analyzed. This is the first report on the occurrence of Xiphophorus maculatus in natural environments of Venezuela. These coastal streams are situated in a zoogeographic transition zone between regional freshwater ichthyofaunas that have a limited number of species, primarily secondary and amphidromous, which could be susceptible to the presence of introduced species. Xiphophorus fish demonstrate the ability to thrive in highly degraded environments, promoting their dispersion and amplifying the impact on the habitat and local fish, particularly small endemic fish, such as the Rivulidae and Poeciliidae.

Aloe vera como modulador de comportamento em Moenkhausia forestti submetido ao transporte

ABSTRACT The ornamental aquaculture market has been expanding, and the transport of living organisms in aquaculture is constant, which affects the behavior and health of these organisms. Due to a lack of methods, small fish species are little studied in ornamental aquaculture. Therefore, the use of bioactives can promote positive responses for the management of these species. This study evaluated the behavior of Moenkhausia forestti transported with Aloe vera powder and Aloe vera gel added to the water. A previous assessment of O2 standards in water with the inclusion of Aloe vera was carried out by measuring dissolved oxygen and pH. An increase in dissolved oxygen was observed over time in treatments with added Aloe vera gel, while a drop in oxygen was observed in treatments with Aloe vera powder after 60 minutes. The fish were subjected to the Control, Aloe vera gel, and Aloe vera powder treatments with 10 fish/bag per repetition. They were transported for 4 hours, and behaviors were evaluated immediately after the transport and after 12 and 24 hours upon arrival. The water conditions and transportation did not significantly affect mortality. The use of Aloe vera powder or Aloe vera gel during transport led to a reduction in stress-related behaviors such as erratic swimming, chasing, and biting.

Red Fluorescent Protein Variant with a Dual-Peak Emission of Fluorescence.

The marine environment is a rich reservoir of diverse biological entities, many of which possess unique properties that are of immense value to biotechnological applications. One such example is the red fluorescent protein derived from the coral Discosoma sp. This protein, encoded by the DsRed gene, has been the subject of extensive research due to its potential applications in various fields. In the study, a variant of the red fluorescent protein was generated through random mutagenesis using the DsRed2 gene as a template. The process employed error-prone PCR (epPCR) to introduce random mutations, leading to the isolation of twelve gene variants. Among these, one variant stood out due to its unique spectral properties, exhibiting dual fluorescence emission at both 480nm (green) and 550nm (red). This novel variant was expressed in both Escherichia coli and zebrafish (Danio rerio) muscle, confirming the dual fluorescence emission in both model systems. One of the immediate applications of this novel protein variant is in ornamental aquaculture. The dual fluorescence can serve as a unique marker or trait, enhancing the aesthetic appeal of aquatic species in ornamental settings.

The Effects of Regulations on the Florida Ornamental Aquaculture Industry Infographic

This infographic accompanies "The Effects of Regulation on Ornamental Aquaculture Farms in Florida" (https://edis.ifas.ufl.edu/publication/FA248), an Ask IFAS factsheet that discusses the results of a study conducted to measure the impact of regulations on ornamental aquaculture farms in Florida using on-farm data from 2018. Florida’s diverse ornamental aquaculture industry has many unique challenges that set it apart from other aquaculture commodity groups. The numerous production techniques, diversity of species, and various market outlets make the ornamental aquaculture industry an intriguing study in how regulations impact the industry. By understanding regulatory impacts, we can streamline efforts to address them.

Aquicultura ornamental como caminho para a introdução de peixes não nativos na drenagem costeira do nordeste do Brasil

Abstract: Aim We present the first record of the introduction of three non-native ornamental fish species, resulting from ornamental aquaculture escapes on the Northeast Mata Atlântica hydrographic ecoregion, with information on the reproductive activity. Methods The specimens were collected bimonthly between 2018 and 2019 using seine and sieve nets, and analyzed for determination of reproductive phases. Results A total of 830 specimens were collected, corresponding to the species Hyphessobrycon eques (N= 311), Poecilia reticulata (N= 500), and Xiphophorus maculatus (N= 19). We used 250 specimens for reproductive analysis. Hyphessobrycon eques and P. reticulata were reproductively active throughout the sampling period. Among the species, the smallest reproductive female measured 22.26 mm (H. eques), 12.53 mm (P. reticulata), and 17.58 mm (X. maculatus). The smallest males measured 20.64 mm (H. eques), 10.71 mm (P. reticulata), and 17.17 mm (X. maculatus). Conclusions The presence of reproductive specimens of H. eques and P. reticulata throughout the year supports the hypothesis of their establishment. We hypothesize that the introduction of X. maculatus is a recent event.

Evaluation of larviculture protocols for the Pacific blue tang (Paracanthurus hepatus)

Aquaculture of marine ornamental fish is an important tool that may help to provide sustainable alternatives to wild caught individuals. Many challenges are associated with marine ornamental aquaculture, especially during the larviculture process. Newly hatched marine larvae are often underdeveloped at hatch and require specific nutritional and environmental parameters for successful morphogenesis and ultimate metamorphosis into the juvenile stage. The Pacific blue tang (Paracanthurus hepatus) is a promising candidate for ornamental aquaculture due to its popularity in the aquarium trade and prior captive breeding success. However, improvements in culture methodologies, especially environmental and nutritional factors, is critical to viable commercial production. Seven experiments were conducted to determine appropriate green water culture conditions, photoperiod, and feeding protocols that best promoted survival, growth, and ingestion rate in early-stage P. hepatus larvae. Larval survival and feeding incidence were significantly increased when live microalgae was added to the culture system. The survival and feeding incidence of 3 days post hatch (DPH) P. hepatus larvae was greatest when the algae species Tisochrysis lutea was incorporated at a density of 300,000 cells/mL. The feeding incidence of 3 DPH larvae was not affected by prey type or prey density. When free amino acid feeding stimulants were added to the culture water, neither larval survival nor feeding incidence were improved. Lastly, the photoperiod that best promoted larval growth and survival was 16-h light: 8-h dark. Together, these results provide for improved larval survival in aquaculture and help move P. hepatus towards viable commercial production.

The Effects of Regulation on Ornamental Aquaculture Farms in Florida

Florida’s diverse ornamental aquaculture industry has many unique challenges that set it apart from other aquaculture commodity groups. The numerous production techniques, diversity of species, and various market outlets make the ornamental aquaculture industry an intriguing study in how regulations impact the industry. By understanding those regulatory impacts, we can streamline efforts to address them. A study was conducted to measure the regulatory impact on ornamental aquaculture farms in Florida using on-farm data from 2018. All farms were censused in the state and results covered 82% of the industry with a response rate of 41% of farms. This factsheet discusses the results of that study and the regulatory burden that the ornamental aquaculture industry in Florida endures.

The pet trade as a source of non-native decapods: the case of crayfish and shrimps in a thermal waterbody in Hungary.

Ornamental aquaculture and the related pet industry are known to be important sources of non-native species worldwide. In the temperate zone, thermal waterbodies are attractive places for irresponsible owners to release unwanted freshwater pets including decapod crustaceans. Several non-native ornamental species have been reported in the thermal locality of Miskolctapolca (a suburb of Miskolc, Hungary). So we surveyed this site in March 2019-November 2021 to update local occurrence records and detect potentially newly released species. A well-established population of Neocaridina denticulata and the occurrence of Caridina cf. babaulti had previously been noted. However, for the first time at this site, we found the shrimps Atyopsis moluccensis, Caridina gracilirostris and C. multidentata, as well as the crayfish Procambarus virginalis, P. clarkii, Cherax quadricarinatus, C. boesemani and C. snowden, and several formally undescribed Cherax species originating from New Guinea. Furthermore, in most species, gravid females carrying eggs were also noticed. Three shrimps, A. moluccensis, C. gracilirostris and C. multidentata, were recorded for the first time in European wild. Further monitoring of this locality and better education of the general public regarding the risks associated with the release of non-native species are strongly recommended.

Larviculture, allometric growth patterns, and gape morphology of the Florida blenny, Chasmodes saburrae

Blennies are cryptobenthic reef fishes (CRFs) that occupy a critical functional group in the trophodynamics of their respective ecological systems and for many of these species there has been renewed interest in their diversity and evolution. Here we provide a robust larviculture methodology for combtooth blennies (f. Blenniidae), that may have applications for both ornamental aquaculture and scientific research. Larval ontogeny, pigmentation, and allometric growth patterns, including gape morphology, of the Florida blenny, Chasmodes saburrae, from the northern Gulf of Mexico (GoM) are described from a complete larval series from hatch to settlement (notochord length/standard length, NL/SL = 3.37–14.49 mm; 1–21 days post hatch, dph). Larvae/settlers were assigned intervals of development using a suite of morphological characters. Allometric growth rates and inflection points of rate change were computed with piecewise linear regressions. Pigmentation and general patterns of development followed that of other blenniid species in the GoM. Growth of all but one morphometric character measured followed a positive allometric growth rate relative to size (NL/SL) after hatching and followed a mostly biphasic growth pattern with inflection points corresponding to phenotypic changes during notochord flexion or prior to settlement and the completion of metamorphosis. A feeding gape size of 26.6% that of maximum gape size was calculated using size at first feeding of prey items and used to estimate an optimized feeding protocol. Based on this gape informed diet, larger and more nutrient rich prey items may be implemented in the feeding protocol between four and eight days earlier than previous study recommends. Captive breeding techniques used during this study show the practical advantages of culturing blenniid larvae with life histories similar to C. saburrae compared with that of most marine fishes currently being cultured and suggests that blenniid larvae may serve as sensible candidates as a model study group for marine teleosts.

A regulatory cost assessment of ornamental aquaculture farms in Florida

AbstractThe ornamental aquaculture trade is a diverse sector of aquaculture and faces unique challenges that other commodity groups do not have to contend with. The various production techniques, species, and destination markets make ornamental aquaculture an interesting study in how regulations impact the industry. In Florida, aquaculture is primarily regulated under the Florida Department of Agriculture and Consumer Services, unique from other states. Regulatory costs and the value of lost production on ornamental farms in Florida were estimated to be $5.2 and $23.2 million, respectively. Results from an industry‐wide census have shown that there is a high regulatory burden on ornamental farmers for some regulatory categories. These include issues of legal control of fish‐eating predators, the restriction of drugs and chemicals, which would be beneficial to production, and the prohibition for farmers to raise species that have been restricted for culture at the national and state level. Larger farms were also able to limit the impact from regulations better than smaller farms by spreading their regulatory costs and value of lost production across greater sales. Although the values of lost production were high for ornamental producers, direct regulatory costs were low compared with other aquaculture commodities demonstrating that the industry in Florida may prove a regulatory model for other sectors.

The fluorescent introduction has begun in the southern hemisphere: presence and life-history strategies of the transgenic zebrafish Danio rerio (Cypriniformes: Danionidae) in Brazil

ABSTRACT Transgenic ornamental fish that fluoresce are becoming popular in the aquarium trade worldwide. Some transgenic zebrafish (TZF) records in natural water bodies have been published, but there are no data on their biological attributes in the new areas. This study aimed to evaluate the distribution, trophic ecology, and reproductive condition of the non-native TZF in headwater creeks located in the largest Brazilian ornamental aquaculture center. Insect fragments – identified as chitinous material in the ‘false stomach’- and aquatic insects were the most consumed item. TZF adults were found in breeding conditions during almost all sampling periods. The Gonadosomatic Index of females and males showed peaks during the rainy season and matched with the rising water levels. Breeding females and males were found at small body sizes, indicating early maturation, and these transgenic females produced a moderate amount of small oocytes. Sex-ratio assessment showed that females and males had the same frequencies in one site, while females were significantly more frequent than males at another location. Management recommendations, such as utilization of best management practices (e.g. screens on outlets), not using unapproved genetically modified organisms in aquaculture, and awareness with fish farmers about transgenic animals, are suggested to avoid new introductions.

Investigations into Early Larval Feeding Practices for the Tiger Barb Puntigrus tetrazona

AbstractThe Tiger Barb Puntigrus tetrazona is one of the highest trade volume freshwater species in the ornamental fish industry. Culture of larval Tiger Barb is largely dependent on live feeds at first feeding and throughout early life stages, leading to increased cost relative to the use of commercially produced microparticulate diets (MDs). Potential for the successful culture of Tiger Barb by using MDs from first feeding was evaluated here, with a focus on the physiological characteristics that limit digestive capacity in larval cyprinids, as well as the hypothetical benefit of including feed attractants in formulated larval feeds. Comparable growth and survival were achieved for the first 14 d of feeding with one of three MDs when compared to feeding with brine shrimp Artemia spp. Histological preparation revealed evidence for a fully functional pharyngeal jaw structure, including pharyngeal teeth and a pharyngeal pad, from 6 d posthatch, which coincided with first feeding. The masticatory function of these structures likely facilitated the breakdown and subsequent utilization of the relatively complex macronutrients that are characteristic of MDs. Inclusion of top‐coated potential attractants (tryptophan, taurine, trimethylglycine betaine, or a mix of the three) with the most successful MD from the original trial failed to induce an increased feeding response, as evidenced by the observation of similar feeding incidence, total larval protein content, and tryptic enzyme activity relative to a negative control MD without added attractants. The results of this research suggest that the successful culture of larval Tiger Barb is possible with the use of commercially available MDs, potentially leading to cost savings and increased resilience of producers in the ornamental aquaculture industry.

Enigmatic armoured catfishes (Siluriformes: Callichthyidae and Loricariidae) in ornamental aquaculture: A new insight into Neotropical fish diversity

Globally, ornamental aquaculture is a multi-million-dollar industry and popular hobby. There are circa 6700 fish taxa being exploited and traded. Various species are traded under commercial names or codes such as certain armoured catfish of families Callichthyidae (C and CW codes or numbers) and Loricariidae (L and LDA codes). Many of these species are imported, reared and multiplied in captivity without their species identification. Here we present a detailed survey of this group of armoured catfish with a special focus on pairing of commercial codes with scientific names. In this context, both species with valid names and scientifically undescribed taxa contributed significantly to the total number of ornamental fish species by circa 25%. In total, 176 species of loricariids and 47 species of small callichthyids were paired with codes used in ornamental aquaculture. The total number of loricariids introduced as ornamentals was estimated to be more than 1000 taxa while more than 500 in small callichthyids. We recommend present findings to all stakeholders and especially taxonomists, conservationists and wildlife managers who are focused on this group of Neotropical fishes. Moreover, formal descriptions of unidentified taxa are required for feasible future monitoring and appropriate management measures of wild populations.

Hitchhiking Exotic Clam: Dreissena polymorpha (Pallas, 1771) Transported via the Ornamental Plant Trade

Ornamental aquaculture is one of the main sources of non-native species worldwide. Unintentionally transported “hitchhiking” organisms have been previously recorded; although most of these species are transported from tropical regions, here we report on the first accidental transport of the zebra mussel (Dreissena polymorpha) in a shipment of ornamental Aegagropila linnaei (Chlorophyta) from Russia to the Czech Republic. This invasive mussel is listed on the national blacklist of alien species in the Czech Republic and can be easily released in outdoor garden ponds together with A. linnaei. Since the Czech Republic is known to be a gateway for aquatic ornamental species from a European perspective, re-export to other European countries is also possible. Thus, the spread of D. polymorpha via this pathway cannot be excluded. This finding should be of importance to conservationists, traders, decision-makers and other stakeholders.

Influence of temperature on larval ontogenesis of Geophagus brasiliensis (Quoy & Gaimard, 1824) (Pisces: Cichlidae).

Studies on the larval development of fish are essential for conservation and improvements in cultivation techniques. Geophagus brasiliensis popularly known as Cará has potential as a fish of interest in ornamental aquaculture. Wild adults of G. brasiliensis were kept in an aquarium for spontaneous reproduction. Newly hatched larvae were transferred to 5-litre aquaria at 22, 26 and 30°C until total yolk sac resorption. Histological slides were used for biometric analysis and monitoring of larval ontogenesis at different temperatures. Histologically, from the first to the fourth days it was possible to identify myomeres, optic vesicle, yolk syncytial layer, brain, heart and differentiation of the eye layers. From the fourth to the seventh days, it was possible to identify mandibular and gill cartilages, swim bladder, liver, prismatic epithelium with striated border in intestine and renal epithelium. All biometric measurements increased over the days, except height and length of the yolk sac, which gradually decreased until the complete resorption of the yolk sac that occurred on the fifth day at a temperature of 30°C, the sixth day at 26°C and the seventh day at 22°C. Morphological events at 30°C such as the reabsorption of the yolk sac, the appearance of cartilage in the branchial arches and differentiation of the layers of the eyes occurred faster compared with the other temperatures tested. Opening of the mouth and digestive tract occurred at a similar time on the fourth day in all temperatures.

Challenging Traditional Gender Roles – Women Empowerment through Ornamental Fish Farming

In the contemporary world, ornamental fisheries /aquaculture is gaining much popularity; in fact, globally it is a trading and marketing industry rather than a hobby. Earlier days, ornamental aquaculture in India was just a hobby for people. Slowly the hobby got momentum to be a viable business as it boomed with trade values internationally. India has enormous potential to be one of the top ornamental fish producing nations as it has huge in untapped or unexploited resources. Ornamental aquaculture can generate income and employment and has immense potential for the upliftment and empowerment of women. Women in fisheries is predominantly involved in post-harvest activities but inclusion of women in aquaculture will help in creating gender equalisation in the sector. Ornamental aquaculture has been tried and tested by several countries, states, and organisations in rural development and the progress of women in all walks of life through ornapreneurship.

Biotic differentiation in headwater creeks after the massive introduction of non-native freshwater aquarium fish in the Paraíba do Sul River basin, Brazil

Abstract This study evaluated fish beta diversity in six headwater creeks located in the area affected by the largest ornamental aquaculture center implemented in the Minas Gerais State, southeastern Brazil. We sampled fish assemblages in 2017 and 2018 to investigate changes in assemblage structure (species richness and beta diversity), comparing these data with the historic species pool. We recorded 60 fish species, of which 16 were native and 44 non-native with 19 translocated, and 25 exotic. The exotics Poecilia reticulata, Xiphophorus maculatus, X. variatus, Danio rerio, and Misgurnus anguillicaudatus were the most widely distributed in the headwater creeks. The Contamination Index showed that most creeks had high proportional contamination by exotic species (above 60%). Beta diversity increased from historical to contemporary periods in all creeks due to the introduction and differential colonization pressure of several non-native translocated and exotic species, indicating biotic differentiation. Temperature and number of ponds were the main preditors of change in beta diversity in the headwater creeks during the contemporary period. In summary, we observed that invaders have induced substantial changes to fish communities under influence of environmental filters. Our results support the hipothesis that aquaculture is a main driver of fish non-native fish introduction and native biodiversity loss in the Neotropics.