Aquarium Fish Research Articles

Understanding the United Kingdom marine aquarium trade - a mystery shopper study of species on sale.

In this study, we conducted a unique survey of marine ornamental fishes appearing in UK retail stores, as well as a review of government trade statistics, with the aim to significantly strengthen the evidence-base in support of future management initiatives. Fifty marine aquarium retailers were visited. A total of 380 marine aquarium fish species (4926 individuals), from 48 families were recorded with the largest proportion of individuals belonging to the families Pomacentridae, Acanthuridae, Apogonidae, Labridae, Pomacanthidae, Gobiidae and Labridae. The majority of fishes for sale (91% of species) originated from the Indo-Pacific Ocean, with only a small number (9% of species) derived from the Atlantic Ocean. However, exact sources of individual species were unclear and poorly documented. Government trade statistics revealed that the ornamental reef-fish trade in the UK grew markedly between 1996 and 2008 with a rapid acceleration in 2003-2004. However, imports have declined since 2008 and amounted to less than 305,000 kg in 2017 with an economic value of UK £3 million (c. US $3.8). Recent trade data (2017) identify Indonesia, USA, Philippines and the Maldives as the most important countries in terms of imports to the UK. The UK is an important exporter of wild-caught fishes via trans-shipment, but also production of tank-reared animals. Several species observed for sale in the UK have been designated by the IUCN and CITES as being of conservation concern, although all these animals are thought to have been captive-reared.

Establishment of Siamese Fighting Fish on the Adelaide River floodplain: the first serious invasive fish in the Northern Territory, Australia

Siamese Fighting Fish Betta splendens is a well-known and popular aquarium fish. The species has recently invaded the Adelaide River floodplain, near Darwin in northern Australia. A very large and extensive population has persisted over consecutive years, with potential for further spread. This represents the first serious alien fish species incursion in the Northern Territory, with reports previously limited mainly to livebearers and cichlids in isolated habitats, some of which have been controlled by specific actions reviewed herein. The invasion highlights the need to maintain and strengthen proactive management, community engagement, and coordinated strategies for vectors of introduction including aquarium fishes.

On the half-life of thiocyanate in the plasma of the marine fish Amphiprion ocellaris: implications for cyanide detection.

The illegal practice of using cyanide (CN) as a stunning agent to collect fish for both the marine aquarium and live fish food trades has been used throughout the Indo-Pacific for over 50 years. CN fishing is destructive to all life forms within the coral reef ecosystems where it is used and is certainly one of many anthropogenic activities that have led to 95% of the reefs in the Indo-Pacific being labeled at risk for degradation and loss. A field-deployable test for detecting fish caught using CN would assist in combating the use of this destructive practice, however, no reliable and robust test exists. Further, there is little toxicokinetic data available on marine fish to support the development of such a test, yet such data is critical to establishing the concentration range and time scale over which such a test would be viable. This study presents the first direct measurement of the half-life of the metabolite thiocyanate (SCN) after pulsed exposure to CN in a marine fish. SCN was measured in the plasma of Amphiprion ocellaris after exposure to 50 ppm CN for three exposure times (20, 45, and 60 s) using HPLC-UV and a C30 column pre-treated with polyethylene glycol. Plasma SCN levels observed are dose-dependent, reflecting a longer time for conversion of CN to SCN as the dose of CN increases. SCN plasma levels reached a maximum concentration (1.2–2.3 ppm) 12–20 h after exposure to CN. The half-life for the elimination of SCN was 1.01 ± 0.26 days for 45 s exposure and 0.44 ± 0.15 days for 20 s exposure. Fish were also directly exposed to SCN (100 ppm for 11 days) and the observed half-life for SCN elimination was 0.35 ± 0.07 days. Plasma SCN levels did not return to control levels, even after 41 days when exposed to CN but did return to control levels after 48 days when exposed to SCN. The similar half-lives observed for CN and SCN exposure suggests that SCN exposure can be used as a proxy for measuring the rate of SCN elimination following CN exposure. In order for plasma SCN to be used as a marker for CN exposure, these results must be extended to other species and endogenous levels of SCN in wild caught fish must be established.

Cold temperature tolerance of albino rainbow shark (Epalzeorhynchos frenatum), a tropical fish with transgenic application in the ornamental aquarium trade

Application of fluorescent protein transgenesis has commercial use for the ornamental aquarium trade by creating new colour phenotypes in various species. To determine the potential for transgenic ornamental aquarium fish to overwinter in Canada, the minimum temperature tolerance of albino rainbow shark (Epalzeorhynchos frenatum (Fowler, 1934)) was estimated to complement a previous study examining cold tolerance of zebrafish (Danio rerio (Hamilton, 1822)), black tetra (Gymnocorymbus ternetzi (Boulenger, 1895)), and tiger barb (Puntius tetrazona (Bleeker, 1855)). Rainbow shark had higher low temperature tolerance limits (LD50 = 10.7 ± 0.1 °C) than surveyed winter water temperatures in Canada. There was a significant negative correlation between condition factor and temperature at loss of equilibrium, suggesting fish with lower social status may be more susceptible to cold temperature than dominant fish. These results indicate transgenic E. frenatum are not expected to persist over winter in Canadian waters.

Acute toxicity of cyanide (KCN) on two types of marine larvae: Acropora sp. planulae and D-veliger larvae of Tridacna squamosa

Cyanide fishing has been intensively used to catch aquarium fishes and fish for human consumption around coral reefs in the South East Asian countries, such as Indonesia. There is little known about the lethal effect of cyanide on the early life stages of marine organisms. We assessed mortality and morphological changes of Acropora sp. planulae and fluted giant clam (Tridacna squamosa) D-veliger larvae exposed to potassium cyanide (KCN) concentrations closed to those used in cyanide fishing. The KCN concentration exposure treatments for coral planulae were 50, 100, 300, 600, and 1000 mg L−1; and those for giant clam D-veliger larvae were 18.875, 37.5, 75, 300, and 600 mg L−1. The 24 hour static-acute toxicity test was used with four replicates for each concentration. The 24h-LC50 was calculated based on Finney’s Probit Analysis Method, and the 24 h-LC50 for coral planulae and giant clam veliger were 121.854 and 84.421 mg L−1, respectively. The D-veliger larvae of Tridacna squamosa were more sensitive to KCN exposure than Acropora sp. planulae. In addition to mortality, we observed that, in both the planulae and D-veliger larvae, morphological abnormalities increased in frequency and severity with increasing KCN concentration, even at the lowest KCN concentrations.

Isolation and Identification of Pathogenic Bacteria Associated with Diseased Fish Cirrhinus mrigala (Ham) in Glass Aquarium

Aquaculture products can anchorage several pathogenic bacterial species, which are known as part of the micro-flora of the environment. The pathogenic bacteria associated with fish can be transmitted to humans as a food source or by handling. The aim of this study was to isolate and identify pathogenic bacteria associated with diseased fish in aquarium. Sampling was carried out under aseptic conditions following standard protocol. Bacterial growth was obtained on different growth media. Total 26 bacterial species were isolated and identified on the basis of cultural, morphological, staining reactions and biochemical analysis. Of the 26 bacterial species, Escherichia coli was the most common bacterium accounting 34.62% (n=09) followed by Aeromonas salmonicida 30.77% (n=08), Staphylococcus aureus 23.07% (n=06) and Salmonella typhi 11.54% (n=03). The isolation of pathogenic bacterial species from fish samples may represent high risk for development of lethal infections in humans utilizing such contaminated/diseased fish as a food source. In summary, the present study has revealed the presence of pathogenic bacterial species in diseased aqua fish. It is therefore suggested to take authentic measures to limit the access of bacterial pathogens in fish acquirams.

What Can Zebrafish Teach Us About Fear?

Fear can sometimes paralyze us, and it can sometimes be exciting; for some people, fear is so crippling it can significantly mix up their lives. We understand a little bit about how the brain acts when we are afraid, mainly by studying the brains of animals. Recently, surprising findings were made using a humble animal, the zebrafish—a small aquarium fish that, in the past, has helped scientists figure out how our organs develop. Zebrafish are useful because they develop quickly, reproduce easily, and have brains that are similar to ours. They also produce what we call an “alarm substance” that alerts their shoalmates when one of them has been injured. When nearby zebrafish smell this substance in the water, they act as if they are very scared. At the same time, they release a substance called serotonin in their brains, which acts as a light switch, making them less afraid but more cautious—as if they are trying to figure out if a predator is close by or not. Hopefully, finding out more about how zebrafish brains process this serotonin signal will help scientists develop better treatments for mental disorders that are associated with fear.

A Study of the Morphological and Histological Structure of the Caudal Fin of the Female Swordtail Fish Xiphophorus helleri and the Effect of Hydrocortisone on it

The caudal fin is one of the most important types of fins used in the movement of fish and is important in studying the effect of various factors on bone, especially medicines and drugs. The females of the Xiphophorus helleri were obtained from aquarium fish shops. The mature females were divided into two groups, each containing 14 fish, placed in 60 liter glass aquarium, the first group treated as control group, while the second group was treated with Hydrocortisone Sodium Succinate (Roxcortisone) with a concentration of 2.5 mg/1. After a month of experimentation, the samples were fixed by a Formalin 10% in order to prepare them for the whole-mount loading method and the normal tissue sections. The results of the phenotypic study of the caudal fins of female X. helleri showed that they consist of three types of fin rays, which are unsegmented and unbranched, segmented and unbranched, and segmented and branched. These three types differ in terms of shape and structure , as histological structures showed that the first type rays, i.e. unsegmented and unbranched, and the first ray of the second type, i.e. segmented and unbranched, have pear shaped. The cavity between the two halves of rays is filled with connective and neural tissue, while the other rays of second type have a heart shape and filled with muscle tissue. The shape of the third type, i.e. segmented and branched, varies depending on their location in the fin. The results of the study of morphological of the caudal fin of females treated with hydrocortisone showed that there was an irregularity in the fin rays in general, which led to a difference in the branching positions of the branched rays compared to the control group. It was also noticed that there was a fusion in the rays composing the fin and another fusion of internodes composing the one fin in comparison to control group. Keywords: Xiphophorus helleri, caudal fin ,fin rays ,hydrocortisone hormone DOI : 10.7176/JNSR/9-4-06

Application of the Transcriptional Disease Signature (TDSs) to Screen Melanoma-Effective Compounds in a Small Fish Model

Cell culture and protein target-based compound screening strategies, though broadly utilized in selecting candidate compounds, often fail to eliminate candidate compounds with non-target effects and/or safety concerns until late in the drug developmental process. Phenotype screening using intact research animals is attractive because it can help identify small molecule candidate compounds that have a high probability of proceeding to clinical use. Most FDA approved, first-in-class small molecules were identified from phenotypic screening. However, phenotypic screening using rodent models is labor intensive, low-throughput, and very expensive. As a novel alternative for small molecule screening, we have been developing gene expression disease profiles, termed the Transcriptional Disease Signature (TDS), as readout of small molecule screens for therapeutic molecules. In this concept, compounds that can reverse, or otherwise affect known disease-associated gene expression patterns in whole animals may be rapidly identified for more detailed downstream direct testing of their efficacy and mode of action. To establish proof of concept for this screening strategy, we employed a transgenic strain of a small aquarium fish, medaka (Oryzias latipes), that overexpresses the malignant melanoma driver gene xmrk, a mutant egfr gene, that is driven by a pigment cell-specific mitf promoter. In this model, melanoma develops with 100% penetrance. Using the transgenic medaka malignant melanoma model, we established a screening system that employs the NanoString nCounter platform to quantify gene expression within custom sets of TDS gene targets that we had previously shown to exhibit differential transcription among xmrk-transgenic and wild-type medaka. Compound-modulated gene expression was identified using an internet-accessible custom-built data processing pipeline. The effect of a given drug on the entire TDS profile was estimated by comparing compound-modulated genes in the TDS using an activation Z-score and Kolmogorov-Smirnov statistics. TDS gene probes were designed that target common signaling pathways that include proliferation, development, toxicity, immune function, metabolism and detoxification. These pathways may be utilized to evaluate candidate compounds for potential favorable, or unfavorable, effects on melanoma-associated gene expression. Here we present the logistics of using medaka to screen compounds, as well as, the development of a user-friendly NanoString data analysis pipeline to support feasibility of this novel TDS drug-screening strategy.

EFFECTS OF RED YAM FLOUR (Ipomoea batatas L.) ON THE GROWTH, SURVIVAL RATE AND SKIN COLOR OF GOLDFISH (Carrasius auratus)

The best quality goldfish requires a good environment and a highly nutritious feed. Thus, this study evaluated the effects of commercial diets supplemented with 0%, 3%, 6%, 9% and 12% red yam flour (Ipomoea batatas L.) on the growth rate, survival rate and skin color of the goldfish Carrasius auratus. A completely randomized experimental design with five treatments and three replicates was used. Seventy-five goldfishes with an average initial length of 4.4 cm were fed the supplemented commercial diets for twenty-eight days inside fifteen experimental tanks. The results showed that the 9% dietary treatment significantly affected the skin color of the goldfishes but not their growth and survival rates (P > 0.05). Hence, the administration of 9% concentrated red yam flour was a suitable dietary supplement to improve skin pigmentation, an important characteristic of aquarium fishes.

Histopathology of the Liver of Three-Spotted Gourami, Trichogaster Trichopterus, Exposed to Malachite Green, A Commonly Used Medicine in Aquaria

With the intensification of aquaculture and the heightened interest in ornamental fishes and fish keeping, use of medicaments has considerably increased. These agents are heavily bio accumulated by fish. In spite of this importance of drugs/therapeutic agents in fishery science, no serious attempt has been made to assess their effects on fishes, especially the histopathological changes brought about by them. Liver is the chief metabolic and detoxification organ in vertebrates and it is highly susceptible to metabolic disturbances and a variety of toxicants to which the animal is exposed. Results of controlled exposure of fishes in the laboratory to toxicants such as pesticides and related chemicals suggest that liver is the organ in which the highest residues of such toxicants accumulate and it is this organ that suffers the greatest damage and impairments following such episodes. The present study was, therefore, aimed at assessing the histopathological effects of therapeutic level of malachite green on the liver of a common aquarium fish, the three spotted (blue) gourami, Trichogaster trichopterus. The drug selected for the present study was malachite green, a chemical recommended for treatment of fishes against several infection, especially fungal infection of eggs. Malachite green is used at concentrations of 0.05-0.15 ppm in fish disease therapy. Healthy fishes of about 70.0±5 mm TL purchased from a local aquarist were used for the present study. Fish were exposed to malachite green for a period of 48 h in all-glass aquarium tanks. The exposure concentration of malachite green was 0.15 ppm. The procedures for histological studies were basically in accordance with the commonly practiced histological methods.

Assessing Vulnerability of Fish in the U.S. Marine Aquarium Trade

The trade in coral reef fishes for aquariums encompasses over 1,800 species from over 40 exporting countries, yet the population status for most traded species is unknown and unevaluated. At the same time, these coral reef fishes face a growing number of threats and often occur in jurisdictions with limited management capacity and data. In response, we assess vulnerability to overfishing for 72 coral reef fishes popular in the aquarium trade for the United States – the top importer – from the top exporting countries (Indonesia and the Philippines). We use a data-limited assessment approach: productivity susceptibility analysis (PSA). PSA estimates relative vulnerability of species by assessing their biological productivity and susceptibility to overfishing. The most and least vulnerable stocks were differentiated by attributes related to the reproductive biology (e.g., breeding strategy, recruitment pattern, and fecundity), appropriateness, ease of capture (e.g., schooling and aggregation), and rates of natural mortality. Our analysis identifies several of the most and least vulnerable species popular in the aquarium fish trade. The species that ranked as least vulnerable to overcollection were Gobiodon okinawae, Nemateleotris magnifica, Gobiodon acicularis, Salarias fasciatus, Ptereleotris zebra, Gobiodon citrinus, Pseudocheilinus hexataenia, Chaetodon lunula, Nemateleotris decora, and Halichoeres chrysus. In contrast, the ten most vulnerable species were Chromileptes altivelis, Plectorhinchus chaetodonoides, Pterapogon kauderni, Premnas biaculeatus, Echidna nebulosa, Centropyge bicolor, Zebrasoma veliferum, Pomacanthus semicirculatus, Zebrasoma scopas, and Thalassoma lunare. In a data-limited context, we suggest how these vulnerability rankings can help guide future efforts for reducing vulnerability risk. In particular, species that are relatively high-vulnerability and high-volume are prime targets for research and aquaculture efforts, increased monitoring of collection and exports, species-specific stock assessments, and voluntary reductions by retailers and consumers to avoid overexploitation.

Status and prospects of gene editing and transgenic in fishes

Recent advances in high throughout DNA sequencing technologies have revolutionized for better understanding of structure-functional relationships of genes in identifying trait-associated transcriptomes and their regulated gene expressions. Subsequent breakthroughs in gene editing technologies such as zinc finger nucleases, transcriptional activator-like effect or nucleases (TALEN) and CRISPR (clustered regularly interspaced short palindromic repeats) determined chromosomal loci so as to understand gene functions in vivo. Such editing technologies are now being implemented in many laboratories due to an affordable cost and easiness of techniques. Targeted gene delivery and disruptions are now not only restricted to standard cell lines or stem cells, but also primary cell lines and nonmodel agriculturally important species. Progress and implications of gene integration and disruptions in food fishes like salmon, carps, etc. will be highlighted. The positive impacts on myostatin gene (negative growth hormone regulator) disruption mediated muscular growth have been documented. Transposon mediated gene integration technologies for value-additions to small indigenous aquarium fishes by expressing attractive fluorescent color genes could be the future of rainbow revolution. Issues linked with further-tuning with regards to improved efficacy and specificity, while reducing offtarget effects of gene editing tools will be addressed. There are health and environmental concerns with genetically modified organisms (GMOs). CRISPR/Cas9 mediated editing generates indels and hence supposed to be free from transgene-nontoxic and non-allergen. Scientific progress regarding to generate genetically modified carps; those could well be cultivated in a confinement and at the same time economically profitable; will be highlighted. Emphasis should be given for transfer these technologies from the laboratory to land for the development of a consumer-friendly sustainable farming system.

Characteristics of bacterial isolates in Swiss farmed and ornamental fish from a retrospective study from 2000 to 2017.

Aquaculture is a rapidly growing field of food production of high economic importance. Bacterial infections are an important threat to aquaculture growth and also a common problem in ornamental fish. Some pathogenic agents and aquaculture production types are reported to be associated with increased disease. However, a detailed description of bacterial pathogens causing disease in Swiss aquaculture and ornamental pet fish is still missing. In this study we describe 1448 bacterial isolations originating from 1134 diagnostic laboratory submissions from farmed and ornamental fish in Switzerland for the period from 2000 to 2017. A strong seasonality was observed with submissions peaking in spring and summer. Bacterial isolations in fish submitted from organic farms were approximately six times more frequent than in conventional fish farms. Flavobacteriaceae, aeromonads and Yersinia ruckeri were the most common isolates from aquaculture, and motile aeromonads and Vibrio spp. were most often isolated from ornamental fish. The results of this study provide some interesting hypotheses, but further research is needed to better characterize risk factors for bacterial diseases in both aquaculture and aquarium fish in Switzerland.

Taxonomically constrained reporting framework limits biodiversity data for aquarium fish imports to Australia

Context Biological resource use represents the most common direct threat to biodiversity. Despite this, there is a paucity of comprehensive and overarching data relating to the biological resource use. The global aquarium trade encompasses millions of individual live fishes representing thousands of marine and freshwater species traded on an annual basis. The lack of specific data systems for recording information where fish are exported or imported has resulted in limited accessible trade data. An evaluation of the data-reporting frameworks presently employed by countries engaged in the aquarium trade is warranted to better understand the means by which comprehensive data on the aquarium trade can be made more accessible. Aims This study examines the data-reporting framework of The Australian Government Department of Agriculture and Water Resources (DAWR) used to collate aquarium fish import data, and its capacity to inform on the aquarium trade biodiversity imported to Australia. Methods Aquarium import records from 2010–16 were provided by DAWR and used to determine the quantity of individual fishes and consignments imported to Australia. The potential biodiversity of imports was determined from the Australian Government’s List of Permitted Live Freshwater/Marine Fish Suitable for Import 2018 (Number 69, F2017C00079), the legislative document identifying species permitted import to Australia for the aquarium trade. Species permitted import were cross-referenced with the International Union for Conservation of Nature (IUCN) Red List to address whether the Australian aquarium trade is importing threatened species. Key results A total of 10320 consignments encompassing more than 78.6 million aquarium fishes were imported to Australia between 2010 and 2016. A total of 4628 species of fishes were permitted import to Australia for the aquarium trade with 73 of the marine species (2.0%) and 81 of the freshwater species (7.5%) found to be threatened with some degree of extinction risk. The data-reporting framework for aquarium fish imports offered limited capacity to taxonomically differentiate imports and only 12.5% of all aquarium fishes imported could be identified to species. Conclusions The aquarium fish import records provided by DAWR had limited taxonomic resolution and, consequently, limited capacity to contribute to an improved understanding of the biodiversity imported to Australia for the aquarium fish trade. While more detailed information is available than is presently collated by DAWR, the availability of this information is constrained by the laws around protected information and the resources available to DAWR. Implications Accessible, detailed information on aquarium fish imports is necessary to support comprehensive research capable of addressing threats to biodiversity loss from the aquarium trade. To this end, the means by which Australian aquarium import data can be reported at greater taxonomic resolution under the existing legislative and resource restraints should be explored further.

Constrained growth of the aquarium fish Black Molly, Poecilia sphenops (Valenciennes, 1846), under the exposure of ZnS nanoparticles

The dose dependent harmful impact of ZnS nanoparticles on the growth of the aquarium fish Black Molly, Poecilia sphenops (Valenciennes, 1846) is studied systematically. Due to the enhanced surface photo-oxidation property associated to ZnS in its nanoparticle form, the dissolved oxygen content and pH value of water are found to reduce in a dose dependent manner from their normal values under the exposure of ZnS nanoparticles in various concentrations. This observation is found to be more intense for ZnS nanoparticles with smaller sizes. P. sphenops, exposed to ZnS nanoparticles responds to hypoxia with altered physiological and behavioural responses in order to retain appropriate organ function in a hypoxic environment. As a consequence, the fish show significantly varied feeding behaviour when compared to the controlled condition. Due to the minimization of food intake, the fish have to use stored lipid and glycogen in their body to maintain essential metabolic activities necessary for survival. Accordingly, the growth of the fish is found to be restricted in accordance to the existing theories.

Conventional Identification of Pathogenic Fungi Isolated from Fresh Water Aquarium Fish (O. niloticus and C. gariepinus) Combined with Molecular Identification of Saprolegnia parasitica in Egypt

Conventional Identification of Pathogenic Fungi Isolated from Fresh Water Aquarium Fish (O. niloticus and C. gariepinus) Combined with Molecular Identification of Saprolegnia parasitica in Egypt

Assessing the conservation potential of fish and corals in aquariums globally

Aquatic ecosystems are indispensable for life on earth and yet despite their essential function and service roles, marine and freshwater biomes are facing unprecedented threats from both traditional and emerging anthropogenic stressors. The resultant species and ecosystem-level threat severity requires an urgent response from the conservation community. With their care facilities, veterinary and conservation breeding expertise, reintroduction and restoration, and public communication reach, stand-alone aquariums and zoos holding aquatic taxa have great collective potential to help address the current biodiversity crisis, which is now greater in freshwater than land habitats. However, uncertainty regarding the number of species kept in such facilities hinders assessment of their conservation value. Here we analyzed, standardized and shared data of zoological institution members of Species360, for fish and Anthozoa species (i.e. Actinopterygii, Elasmobranchii, Holocephali, Myxini, Sarcopterygii and Anthozoa). To assess the conservation potential of populations held in these institutions, we cross-referenced the Species360 records with the following conservation schemes: the Convention on the International Trade of Endangered Species of Fauna and Flora (CITES), the IUCN Red List of Threatened species, climate change vulnerability, Evolutionary Distinct and Globally Endangered (EDGE) and The Alliance for Zero Extinction (AZE). We found that aquariums hold four of the six fish species listed by the IUCN Red List as ‘Extinct in the Wild’, 31% of Anthozoa species listed by Foden et al. (2013) as vulnerable to climate change, 19 out of the 111 Anthozoa EDGE species, and none of the species prioritized by the AZE. However, it is very likely that significant additional species of high conservation value are held in aquariums that do not manage their records in standardized, sharable platforms such as Species360. Our study highlights both the great value of aquarium and zoo collections for addressing the aquatic biodiversity crisis, as well as the importance that they maintain comprehensive, standardised, globally-shared taxonomic data.

Effects of Live Food Feeding on Growth Performance and Some Histological Parameters of Herotilapia multispinosa and Amatitlania nigrofasciata

<div><!--block-->Aquarium fish feeding is an expensive hobby. Live foods such as Artemia are highly expensive and widely used. Therefore, aquarists look for alternative live food sources to feed their fish. Nematodes and annelids are good sources of protein and are easy to produce. In this study, we evaluated the effects of nematode and annelid feeding on the on growth performance and some histological parameters of Herotilapia multispinosa and Amatitlania nigrofasciata compared with commercial feeds. A. nigrofasciata fish groups fed with live and commercial food showed the highest survival rates of 91% and 100%, respectively. However, H. multispinosa fish groups fed with live food showed inhibited growth. Histologic examination of the liver and intestines revealed negative effects on these aquarium fish. Thus, right feeding regime practices should be established for using nematodes and annelids as fish food sources.</div>

THE IMPORTANCE OF CEARÁ STATE TO THE BRAZILIAN MARINE ORNAMENTAL FISH EXPORTS

O Brasil é um dos principais fornecedores mundiais de peixes ornamentais marinhos e Ceará é o estado exportador de maior relevância no país. Entretanto, existe uma carência de informações atualizadas sobre a atividade, o que é crucial para a explotação sustentável desses organismos. Assim, o presente trabalho fornece os dados mais recentes em relação às exportações brasileiras e, mais especificamente, cearenses de peixes ornamentais marinhos, por meio da análise de informações contidas em 420.871 autorizações de exportação emitidas pelas autoridades ambientais brasileiras nos últimos 10 anos. Os resultados corroboram a relevante paraticipação do estado do Ceará nas exportações nacionais de peixes ornamentais marinhos, mas também mostram um declínio substancial dessa atividade ao longo da última década. Dezesseis espécies foram as mais abundantes e frequentes tanto nas exportações brasileiras quanto nas cearenses. Não surpreendentemente, os pomacantídeos foram os peixes mais importantes comercializados, e provavelmente mais de 283.525 indivíduos foram capturados na natureza em um intervalo de aproximadamente 10 anos. Atualmente as exportações brasileiras são direcionadas principalmente para os países asiáticos e deslocamentos sazonais da Zona de Convergência Intertropical (ZCIT) parecem interferir na coleta de peixes ornamentais no Ceará, impactando