Ornamental Fish Species Research Articles

GONADOSOMATIC INDEX OF NANDUS NANDUS (HAMILTON, 1822)

Ornamental fishes have emerged as a resource with considerable economic potential. The Asian region stands up as the largest importer of tropical ornamental fish trade. In 2007, it exported 56% of the total global share. Singapore exports the largest share occupying 38% followed by Malaysia, Japan and Thailand by 14%, 12% and 8% respectively ( FishStat, 2009). Compared to the Asian scenario India's total share is negligible in the ornamental fish trade. India is endowed with rich resource of ornamental fish species and can become a major contributor to the international market. Northeastern region can also contribute a major share in the trade of India with its diversified water bodies. The major area which needs to be focused is breeding of ornamental fishes. A successful breeding programme can be possible only if the breeding season of the fish is known. In order to complete the task, the present study was undertaken to trace accurately the spawning period of Nandus nandus. This is reported in terms of gonadosomatic index, which express the relative change in gonad weight to the percentage of body weight.

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.

Establishment and range expansion of non-native fish species facilitated by hot springs: the case study from the Upper Sakarya Basin (NW, Turkey)

AbstractNon-native species can enter new habitats and ecosystems in a variety of ways. Suitable ecological conditions must exist for non-native species to reproduce in newly colonized habitats. Hot springs are suitable habitats for tropical, aquarium, and ornamental fish species. This paper presents the results of research on the distribution of non-native and native species in relation to environmental factors in the Upper Sakarya Basin, where several such springs are present. The fish fauna in the basin includes native (60% – 21 species, 14 of which are endemic) and non-native (40% – 14 species) fish species. Most of the non-native species (seven species) were found only in warm springs (minimum water temperature 16°C). In addition, 75 fish species belonging to 26 families were found throughout the Sakarya Basin. Hot springs were found to play an important role in the establishment of non-native species. The Kernel Density Estimation (KDE) results revealed that the non-native species density was high in the Upper Sakarya Basin where hot springs are common. This confirms that minimum and maximum temperatures are the main drivers of changes in the distribution of non-native fish species. Two aquarium fishes,Bujurguina vittataandXiphophorusspp., are reported for the first time in the present study for inland waters of Turkey.

De Novo Transcriptomic Characterization Enables Novel Microsatellite Identification and Marker Development in Betta splendens.

The wild populations of the commercially valuable ornamental fish species, Betta splendens, and its germplasm resources have long been threatened by habitat degradation and contamination with artificially bred fish. Because of the lack of effective marker resources, population genetics research projects are severely hampered. To generate genetic data for developing polymorphic simple sequence repeat (SSR) markers and identifying functional genes, transcriptomic analysis was performed. Illumina paired-end sequencing yielded 105,505,486 clean reads, which were then de novo assembled into 69,836 unigenes. Of these, 35,751 were annotated in the non-redundant, EuKaryotic Orthologous Group, Swiss-Prot, Kyoto Encyclopedia of Genes and Genomes and Gene Ontology databases. A total of 12,751 SSR loci were identified from the transcripts and 7970 primer pairs were designed. One hundred primer pairs were randomly selected for PCR validation and 53 successfully generated target amplification products. Further validation demonstrated that 36% (n = 19) of the 53 amplified loci were polymorphic. These data could not only enrich the genetic information for the identification of functional genes but also effectively facilitate the development of SSR markers. Such knowledge would accelerate further studies on the genetic variation and evolution, comparative genomics, linkage mapping and molecular breeding in B. splendens.

Neobenedenia melleni from reef ornamental fish species in a retailer of Southeastern Brazil and its possible role as a mechanical vector of bacterial infection.

Annually, more than 2500 ornamental fish species are traded worldwide. Forty percent of these are from marine water. Some 98% of marine species are wild-caught from their natural habitat, and the majority subsequently exported. Wild fish frequently carry pathogens, which could induce diseases after the stress of capture. Neobenedenia melleni is a platyhelminth that mainly attaches to the skin and eyes of the host. It provokes dermal inflammation, epidermal loss, skin depigmentation, reduction in the number of mucous cells, and, consequently, decreased mucus protection, and declining immunological barriers. This makes fish susceptible to secondary infections. A total of 47 wild reef fish from a retailer were examined, suspected to be infected with ectoparasites. The morphological identification revealed N. melleni as a monogenean agent. One monogenean specimen was collected from the eye of each of the 40 fish analyzed to evaluate possible bacterial secondary infections using the matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) technique. The MALDI-TOF MS identified that 59% of monogenean collected from the eyes had bacteria, including some pathogenic to fish. This led us to believe that the ectoparasite can be a possible mechanical vector of pathogenic bacteria for fish culture and maintenance. The use of praziquantel as an antiparasitic agent is also discussed.

Preliminary Investigations into Use of Metomidate for Euthanasia of Ornamental Fishes

The goals of this study were to investigate the potential use of metomidate for one-step euthanasia of ornamental fish species representing commonly sold families in the ornamental fish trade and to determine a baseline euthanasia dose for most species tested. Metomidate hydrochloride, a rapid-acting, water-soluble, nonbarbiturate hypnotic related to etomidate, was tested at various concentrations and durations for euthanasia of species representing the following freshwater and marine aquarium fish families: Apogonidae, Ariidae, Blenniidae, Callichthyidae, Characidae, Cichlidae, Cyprinidae, Gobiidae, Gyrinocheilidae, Loricariidae, Melanotaeniidae, Osphronemidae, Pimelodidae, Poeciliidae, Pomacentridae, and Pseudochromidae. Fish in each trial were euthanized as a group (n=1). Most groups contained 10-12 fish. Some higher doses required buffering. Euthanasia was considered successful if all fish in each group did not recover after 6h in unmedicated water. All species immediately lost buoyancy and equilibrium, dropping to the tank bottom within 1min and ceasing ventilation typically within minutes. However, reactivity to vibration, sound, or touch was noticeable for varying time periods afterward (8-66min), so an additional 30min of exposure after cessation of reactivity was included as part of the protocol. Although some species (Neon Tetras Paracheirodon innesi and Australian Rainbowfish Melanotaenia australis) were euthanized at a concentration of 40mg/L metomidate for a total exposure time of 38min, most species tested were successfully euthanized with metomidate at a concentration of 100mg/L, with total exposure times ranging from 35-96min. A few catfish species (Otocinclus sp. and Bronze Corydoras Corydoras aeneus) were refractory and recovered after 100mg/L. However, Otocinclus sp. were successfully euthanized at 250mg/L, and Bronze Corydoras were euthanized at 1,000mg/L. Further studies are needed to provide additional data for these and other species and families, for different water chemistry conditions, and for various biological factors to fine-tune dosing regimens.

Systemic mycobacteriosis along with concurrent fibroma in Goldfish, Carassius auratus from India

Aim: Goldfish (Carassius auratus L.), a freshwater fish belonging to the family Cyprinidae, is an important ornamental fish species in the world. Herewith, we report a case of systemic mycobacteriosis along with concurrent fibroma in goldfish. Methodology: The protruding mass and internal organs exhibiting lesions were collected for histopathology and molecular diagnosis. The sections of cutaneous mass were stained with haematoxylin and eosin (H&E) and Masson trichrome, whereas sections from spleen as well as kidney were stained with H&E and Ziehl-Neelsen. For identifying the etiological agent, 16S rRNA gene fragment was amplified and sequenced, using genus-specific primers for Mycobacterium sp. Results: In histopathology, multiple granulomas could be observed in kidney and spleen sections. Importantly, typical acid-fast bacilli were demonstrated in granulomas in spleen. The sequence of 16S rRNA gene fragment amplified from spleen and kidney showed maximum similarity to Mycobacterium stomatepiae. Besides, the histopathological characteristics of the protruding mass were consistent with cutaneous fibroma. Interpretation: These findings assume significance as several Mycobacterium species, including the current one from ornamental fish are reported to be of zoonotic significance.

Ichthyological ethnoknowledge of the \u201cpiabeiros\u201d from the Amazon region, Brazil

BackgroundThe capture of ornamental fish is one of the main economic activities of riverine families in the Amazon. However, studies regarding the local ecological knowledge of workers in this activity are still incipient. In view of this, we have studied and explored the local ecological knowledge of artisanal fishers who specialize in the capture of fish for the aquarium trade in the middle part of the Negro River basin and investigated issues related to the ecological aspects of the fish species that are targeted by this trade in the region.MethodsTherefore, we conducted semi-structured interviews and applied questionnaires to artisanal fishers of ornamental fish (N = 89), from the municipality of Barcelos, from January to April 2016.ResultsIn total, 41 popular names were cited, which correspond to four ethnocategories and 10 families. The main species were Paracheirodon axelrodi (12.5%), Hemigrammus bleheri (8.3%), Ancistrus dolichopterus (6.4%), Symphysodon discus (5.3%), and Potamotrygon motoro (3.8%). According to the fishers, the species of fish known in the region as “piabas” have a preference for living in clusters (28.9%) and carry out migratory movements (26.1%). The diet of local fish species reported by fisheries is diverse, though mainly based on periphyton (42.2%), and the reproductive cycle directly influenced by the period of flooding of rivers in the region (37.6%)ConclusionOur study revealed that the fishers possess information on the ecological aspects of local ornamental fish species, many of which are consistent with scientific literature. The information presented may assist in the decision-making process for the management of local fishery resources and contribute to the resumption of growth and sustainability in the capture of ornamental fish.

SPAWNING OF BLACK GHOST KNIFEFISH, Apteronotus albifrons WITH DIFFERENT SEX RATIOS

Black ghost knifefish, Apteronotus albifrons, is a South America-introduced ornamental fish species that has been widely cultivated in Indonesia. Some farmers breed this fish with different sex ratios, but the optimum sex ratio remains unclear. This study aimed to evaluate the spawning behavior and reproductive performance of black ghost knifefish with different sex ratios. The treatments in this study were arranged in a completely randomized design consisting of different sex ratios between males and females, namely: A (one male : three females), B (two males : three females), and C (three males : three females). Each treatment was done in triplicate. The broodstock were maintained in an aquarium (80 cm x 40 cm x 40 cm) and fed with bloodworm twice a day. The water was changed every day as much as 60% of the total volume. During the experiment, the parameters of spawning behavior, number of fish spawning, number of eggs, fertilization rate, hatching rate, and daily spawning frequencies were observed. The observation was done for seven days. The study results showed that black ghost knifefish spawned at night (11 pm - 2 am). The mating and spawning occurred between one male and one female. Competition between males was observed in the treatments indicated by aggressive movements of a male toward the others, such as sudden approaching, chasing, and driving away the others. Fish in treatment-B spawned consistently from day-1 to day-5. Fish in treatment-A spawned from day-2 to day-4, while fish in treatment-C spawned only on day-7. The reproductive performance parameters showed no significant difference in all treatments except the hatching rate parameter of treatment-B. The study concludes that better reproductive performance of black ghost knifefish, A. albifrons can be achieved with a spawning ratio of two males and three females. Further research on individual and mass spawning methods with the best spawning ratio of the fish is required.

Do non‐native ornamental fishes pose a similar level of invasion risk in neighbouring regions of similar current and future climate? Implications for conservation and management

Abstract Global trade in non‐native ornamental species coupled with high connectivity among countries is well known to result in worldwide biological invasions, which pose challenges for the conservation and management of biodiversity. There are few studies aimed at implementing management strategies that have examined differences in the potential invasiveness of non‐native species between neighbouring political regions within the same ecoregion. To compare the potential risk of invasiveness of non‐native ornamental fishes with high commercial value in the river basins of two neighbouring regions of East and Southeast Asia, 32 extant and horizon species were screened with the aquatic species invasiveness screening kit (as‐isk) for the lower Pearl River basin (South China) and the Chao Phraya River basin (Thailand). Both regional (i.e. basin level) and combined risk‐ranking thresholds were determined by receiver operating characteristic curve analysis. Of the 32 species screened, 14 were categorized as posing a high risk and seven were categorized as posing a medium risk of being invasive in both regions, under current and future climate conditions. These species have a history of invasiveness and the climate of their native ranges is similar to that of the two study regions. Pterygoplichthys pardalis received the highest risk score in both regions. The risk ranks of 11 species differed between the two regions, based on either the combined or regional thresholds, and this was partly related to the different risk of invasiveness between the two regions, coupled with cognitive subjectivity among the assessors. The results of the present study suggest that the invasion of non‐native ornamental fish species could pose similar threats to biodiversity in neighbouring regions. This will serve to inform policy makers of neighbouring countries in the development of coordinated, mutually beneficial regulations and management strategies to enhance the conservation of native species.

Türkiye Tatlısularında Egzotik Yeşil Kılıçkuyruk(Xiphophorus hellerii)’nin İlk ve Lepistes (Poecilia reticulata)’nın İlave Kaydı

Livebearer poeciliids, with few exceptions, are among the most popular and highly traded ornamental fish species. Therefore, they are frequently introduced to natural waters outside their native range mostly by the aquarium hobbyists. Here we report feral populations of two exotic poecilid species, the swordtail (Xiphophorus hellerii) and the guppy (Poecilia reticulata), established in a hot spring in the Eastern Turkey. This is the first documented record of swordtail in Turkey and possibly the first records of the two species in the wider Euphrates Basin. More research is needed to address the potential impacts of these two poecilids on the native biota, and also their further spread chance and management options.

Length‐weight relationships of ornamental fish species from Amanã Lake, Amanã Reserve, Amazonas, Brazil

Length‐weight relationships of ornamental fish species from Amanã Lake, Amanã Reserve, Amazonas, Brazil

Classifying five ornamental fish species of Cichlidae family by use of logistic regression and discrimination linear analysis

Classifying five ornamental fish species of Cichlidae family by use of logistic regression and discrimination linear analysis

Comparison Between Blood Haematology of Egyptian Freshwater Food Fish and Ornamental Fish

The present study was carried out to compare between some freshwater food fish species and some other freshwater ornamental fish species commonly known in Egypt, concerning the haematological parameters, dressing percent, fillet (boneless meat) percentage, and chemical composition of the fish flesh on dry matter basis. Four food fish species (Nile tilapia, grass carp, catfish, and Tobara from Manzalah Fish Farm, Dakahlia governorate, General Authority For Developing Fish Wealth, Ministry of Agriculture, Cairo, Egypt) and two ornamental fish (Koi and Fan-tail (Goldfish), from local ornamental fish trade shops, Mansoura, Dakahlia governorate, Egypt) species all belonging to the freshwater fishes were sampled, three fishes from each. Body measurements of the individual fishes were recorded, blood samples were withdrawn, live body weight was recorded, fish were dressed (eviscerated) and filleted, the flesh were minced, dried, and sieved for chemical analysis. From the forgoing results, it could be concluded that the worthiness comparison among fish species for physical, biochemical and haematological parameters, and fish quality must be done between similar species, sex, size, physiological status, nutritional status, rearing system. These parameters are variable and influenced by genetically and environmental aspects.

Comparative Transcriptome Analysis Identifies Candidate Genes Related to Black-Spotted Pattern Formation in Spotted Scat (Scatophagus argus)

Spotted scat (Scatophagus argus) is an economically important marine aquaculture and ornamental fish species in Asia, especially in southeast China. In this study, skin transcriptomes of S. argus were obtained for three types of skin, including black-spotted skin (A), non-spotted skin (B) and caudal fin (C). A total of nine complementary DNA (cDNA) libraries were obtained by Illumina sequencing. Bioinformatics analysis revealed that 1358, 2086 and 487 genes were differentially expressed between A and B, A and C, and B and C, respectively. The results revealed that there were 134 common significantly differentially expressed genes (DEGs) and several key genes related to pigment synthesis and pigmentation, including tyrp1, mitf, pmel, slc7a2, tjp1, hsp70 and mart-1. Of these, some DEGs were associated with pigmentation-related Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, such as tyrosine metabolism, melanogenesis, the Wnt signaling pathway and the mitogen-activated protein kinase (MAPK) signaling pathway. The results will facilitate understanding the molecular mechanisms of skin pigmentation differentiation in S. argus and provide valuable information for skin coloration, especially the formation of spotted patterns on other marine fish species.

Complete mitochondrial genome of nearly threatened freshwater ornamental fish, Microphis deocata and its phylogenetic relationship within Syngnathidae

Microphis deocata (deocata pipefish), belonging to family Syngnathidae, is one of the important indigenous ornamental fish species listed as near threatened in the IUCN red list. Here, we first report the complete mitochondrial genome of deocata pipefish using Illumina next-generation sequencing platform. The total length of the mitogenome is 16,526 bp. It encompasses 13 protein coding genes, 2 ribosomal rRNAs, and 22 tRNAs. The WANCY region (a cluster of five tRNA genes) contains the 50 bp OL light strand origin of replication. Phylogenetic analysis of Syngnathidae revealed M. deocata to cluster with Oostethus manadensis, forming a sister group with Doryrhamphus japonicas and Dunckerocampus dactyliophorus. The mitochondrial genome sequence data generated in the present study will play an important role in population genetic analysis and developing conservation strategies for this species.

Vulnerability assessment of Lake Malawi’s ornamental fish resources to export ornamental trade

Productivity Sustainability Analysis (PSA) was used to assess the vulnerability of 103 most targeted ornamental fish species of Lake Malawi to fishing for the export trade. The PSA was based on five productivity and four susceptibility attributes that are relevant to the ornamental fishes of Lake Malawi, and for which information was readily available from the scientific literature. The vulnerability scores ranged from 1.78 to 3.84 with a mean value of 2.49. Seven species (Aulonocara sp ‘walteri’, Lethrinops sp ‘red cap’, Aulonocara baenschi, Copadichromis azureus, Melanochromis chipokae, Placidochromis phenochilus and Protomelas sp ‘mbenji thick lips’) were classified in the high-vulnerability category with vulnerability scores ranging from 3.18 to 3.84. Twenty-five species were within the medium vulnerability category with scores between 2.64 and 2.96 while 71 species ranked as of low vulnerability scores ranging between 1.78 and 2.63. The vulnerability scores were positively correlated with IUCN conservation status (τb = 0.286, p = 0.001). Susceptibility scores had a stronger correlation with the IUCN risk assessment criteria (τb = 0.390, p < 0.001) compared to the productivity scores (τb = -0.023, p = 0.805). In addition, the susceptibility scores contributed more to the vulnerability scores for species ranked to be of high-vulnerability, which provides a potential scope for management interventions. The findings validate the use of the PSA for assessing freshwater ornamental fish species. Use of the PSA approach has an added advantage of being applicable for undescribed species which are difficult to assess using other vulnerability assessment approaches. The potential for promoting the export of low-vulnerability ornamental fish species; while prioritizing conservation of high-vulnerability species is evident, coupled with quantitative research to inform the development of precautionary management measures.

Length-weight relationships of five ornamental fish species harvested from a tributary of Bira Cot River, Indonesia

Aceh Besar, Indonesia has a big potency on fisheries resource, including small fish that have potential as ornamental fish, such as Zebrafish, Checker barb, Rasbora, and Hasselt’s Loach. To date, information on the growth pattern of this species was not available. Hence, the objective of the present study was to examine the growth pattern of five ornamental fish species namely; Danio albolineatus, Puntius oligolepis, P. binotatus, Rasbora sumatrana and Lepidocephalichthys hasselti. The fish sample was collected from Bira Cot River, Aceh Besar District from February to July 2020. In Bira Cot, Aceh Besar District, Indonesia. The study showed that the a and b values of regression parameters ranged between 0.0025-0.0097 and 3.043-3.545, respectively. The growth pattern of P. oligolepis, D. albolineatus and L. hasselti had a positive allometric growth pattern, while P. binotatus and R. sumatrana showed an isometric growth pattern. Based on the condition factors parameter indicated that the condition of the waters of the sampling location is still in good condition and supports the life of fish.

Food and feeding habits of two species ornamental fishes from Bira Cot, Aceh Besar, Indonesia

Food and feeding habits of the two ornamental fish species confined to 2 genera and 1 family from Bira Cot River. The study has been conduction between February, 2020 and July, 2020. A total of 20 fishes were randomly collected from Bira Cot River during the study period. Observation was made for the total length, standard length, body weight, relative length of alimentary canal and qualitative and quantitative analysis of stomach contents. The relative length of alimentary canal was described in relation to feeding habit. The stomach content analysis indicated that Danio albolineatus omnivores while Puntius oligolepis herbivores. In the present study, the determination of food composition and feeding habits of studied fish species may give some important information for culture of these ornamental freshwater fish species.

Economic contribution and attitude towards alien freshwater ornamental fishes of pet store owners in Klang Valley, Malaysia

Malaysia is one of the top ten countries in the world that produce freshwater ornamental fishes. This industry can offer better livelihood opportunities to many poor households. However, most of the produced ornamental fishes are alien to Malaysia. In this study, we explore the contribution of alien freshwater fishes to the income of ornamental fish store owners and their attitude towards alien freshwater fishes within Klang Valley, Malaysia. Using a structured questionnaire, we surveyed 70 pet stores out of which 54 (81.42%) store owners responded. Most of the pet store owners were male (72%), Chinese (83%), and the highest educational level was at the secondary level (79%). Most of the pet store owners reported a monthly income of RM 2001–RM 5000 (78%) and were married (73%). Using Chi-square (χ2) test, significant relationships (p < 0.05) existed between the attitude of store owners towards alien ornamental fish species versus educational level (χ2 = 16.424, p = 0.007) and contribution of alien ornamental fishes to the pet store owners’ income (χ2 = 27.266, p = 0.003). Fish sales as the main income source also related significantly with the impact of fish selling business on income level (χ2 = 10.448, p = 0.007). This study showed that the ornamental fish sales contributed over half of the income (51–100%) from the businesses of store owners. Almost half of the respondents (42%) reported that alien ornamental fish was the highest contributor to their income from the ornamental fish sale. While the mismanagement of alien ornamental fishes could give various negative ecological impacts, the socio-economic benefits of these fishes cannot be denied.