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Mycobacterium marinum is a non‐tuberculous mycobacterium which can be found in naturally occurring, non‐chlorinated water sources and is a known pathogen that affects fish. In humans, M. marinum typically results in cutaneous lesions, it can occasionally lead to more invasive disorders. We discuss four cases of M. marinum‐related cutaneous infections examined in a tertiary care facility. We want to draw attention to the challenges of accurately diagnosing this infection, stress the significance of having a high level of clinical suspicion in order to identify it, and discuss the available treatment choices. [ABSTRACT FROM AUTHOR]

The study was conducted to assess the effects of using Galleria mellonella larvae (GML) as an unconventional protein source (insect protein) replacing soybean meal (SBM) in the Nile tilapia diets. Approximatley 180 fish (with an initial average body weight of 5.6±0.18g) were randomly assigned among 12 experimental aquariums, with 15 fish per aquarium, giving three replicates of 45 fish for each treatment. GML replaced 0, 5, 10, and 15% of the soybean meal, which constituted 40% of the control diet. These replacements were corresponding to 0, 20, 40, and 60g/ kg for diets D1, D2, D3, and D4, respectively, for 56 days. All test diets were designed to be iso-nitrogenous. At the end of the experiment, growth productivity, feed utilization, body composition, biochemical analysis, immune parameters and economical evaluation were examined. The results indicated that, metrics such as FW, TBWG, ADG, SGR, and SR showed improvements in diets D2, D3, and D4, with a mortality rate of 6.67% in the control group (D1) and 0% in the other treatments. Fish fed on GML diets D2, D3, and D4 demonstrated a significant (P< 0.05) increase in FI, FCR, CPI, PER, energy retention percentage and lysozyme activity in all treatment groups compared to the control, whereas there were non-significant changes (P> 0.05) in ALT, AST, glucose, and cholesterol. Additionally, feed formulation costs decreased, with net improvements in the feeding cost percentages of 6.17, 8.70, and 10.07% for diets D2, D3, and D4, respectively, compared to the control group. The study revealed that using GML as an insect protein holds great potential as a substitute for SBM feeds to increase the production of the Nile tilapia. [ABSTRACT FROM AUTHOR]

The vulnerability of cownose rays (Rhinoptera bonasus) to anthropogenic pressures, such as overfishing and habitat degradation, necessitates urgent and comprehensive conservation efforts to ensure the species' survival and maintain the marine ecosystem balance. In this study, six cownose rays, acquired post-mortem from a public aquarium, were meticulously examined under controlled laboratory conditions. Through the PCR targeting of the housekeeping genes and subsequent sequencing, gene fragments were concatenated into a 2022-bp sequence deposited in the PubMLST database. PCR and sequence analyses identified two distinct Vibrio isolates, labeled as gv9 and gv10, which by MLSA analysis were shown to be closely related to Vibrio atlanticus and Vibrio rotiferianus. A novel sequence type, ST 247, was identified, suggesting allelic differences compared to 60 closely related Vibrio species. Despite the absence of external lesions, internal examination revealed muscular, uterine, cardiac and endometrial hemorrhage, valvular intestinal dilatation, uterine pus accumulation, and pyometra. Histopathological examination demonstrated hemorrhage in the heart muscle, an increased number of microglial cells in the brain and severe vacuolar degeneration in the liver. This study provides insight into the intricate association between cownose rays and Vibrio bacteria, as well as the potential role of these bacteria in the pathologies observed. [ABSTRACT FROM AUTHOR]

The increasing popularity of fish keeping in aquariums and the need for electronic equipment to maintain an optimal environment. This article focuses on monitoring water purity to ensure fish health and longevity, addressing the issue of water pollution caused by chemicals and waste produced by fish. Solutions such as mechanical and biological filters are explored, highlighting the use of the mechanical filter composed of zeolite, ceramic rings, and activated carbon, which work to remove solid particles, toxic compounds, and pollutants from the aquarium water. The article presents the implementation of a mechanical filter controlled by a PIC18F4550 microcontroller using a pH sensor. The results indicate the stability of the pH of the water in the established range of 6.5 to 7.5, with a maximum error of 3% at the upper limit of the range and no error below the established lower limit. It is concluded that the system effectively maintains the desired levels and ensures the fish's health. A technological solution for monitoring and controlling water quality is presented, recognizing the possibility of improvements in aquaculture. [ABSTRACT FROM AUTHOR]

In this study, the larval development stage of the penguin tetra fish (Thayeria boehlkei), a popular species in the freshwater aquarium fish industry, was investigated. For this purpose, penguin tetra larvae were morphologically observed from time to hatching until they reached the juvenile stage. Throughout the larval development phase, samples were randomly taken daily and captured on a camera using a stereomicroscope. Larval development stages were categorized into four periods: (I) Yolk-sac larva, (II) Pre-flexion larva, (III) Flexion larva, and (IV) Post-flexion larva. Larvae were fed with Artemia nauplii until they reached the juvenile stage for the entire research. Morphological changes, including the state of the yolk sac from hatching, mouth opening, changes in body shape and color, and fin formation processes, were recorded daily. According to the findings, the mouth opened on the 5th day, and external feeding also started on the 5th and 6th days. At the same time, free swimming movements were observed in the larvae, and it was determined that the yolk sacs were consumed. The flexion larva stage occurred on the 15- 16th days. The larval development process of the penguin tetra fish was completed within 25 days after hatching. After this stage, the juveniles became morphologically identical to their parents. [ABSTRACT FROM AUTHOR]

The study aimed to evaluate the ability of the red tilapia (Oreochromis sp.) to withstand varying unionized ammonia and water salinity levels on growth performance, feed utilization, and physiological state. Three distinct unionized ammonia concentrations of 0.15, 0.20, and 0.25mg/ l and two different levels of water salinity of 25 and 30ppt were assigned in six treatments (T1 through T6), each with three replicates. Eighteen aquariums held a total of 180 red tilapia distributed equally among them. Ten fish were placed at random in these aquariums, with an average initially body weight of 19.42± 0.04g and an initial body length of 8.48± 0.51cm. The experimental fish were fed commercial feed (30% crude protein) at a rate of 3% of their total biomass three times a day, at 08:00, 13:00, and 18:00, for 8 weeks. Blood samples were taken from five fish in each aquarium at the end of the trail to measure the hematological and biochemical parameters. The findings show that the interaction between unionized ammonia and the water salinity had no discernible effect on the majority of growth and feed utilization indices. WBCs, platelets, and MCHC levels were highest in T5, T3, and T4, respectively. T1 had the highest globulin value and urea contents, while T2 recorded the greatest values of liver enzymes ALT and AST. The current study suggests that different unionized ammonia levels affected fish health and quality, but water salinity decreased these effects slightly and allowed the red tilapia to grow well in high salinity water. [ABSTRACT FROM AUTHOR]

Ornamental fish aquarium globally is considered a key sector of aquaculture and represents a significant portion of the pet industry. Between June 2022 and February 2023, a total of 229 goldfish were examined to investigate the histopathological lesions associated with the parasitic fauna (Carassius auratus) collected from Elsaieda Aisha market in Cairo governorate, Egypt and some pet shops in Beni-suef and Elfayoum governorates. The overall prevalence of parasitic infections was 47.2 %. The isolated parasites include protozoan parasites (Trichodina spp., Ichthyophthirius multifiliis, Chilodonella sp. and Icthyoboda necator), monogeneans (Dactylogyrus sp. and Gyrodactylus sp.), Encysted meta cercaria of Centrocestus formosanus, crustaceans ( Lernaea sp. and Argulus sp.) and one nematode Capillariasp. with incidence rates 27.9%, 15.3%, 2.6%, 12.7% and 0.4% respectively. Gross examinations of the affected fish were varied and appeared as hemorrhage on the body' with excessive mucus production, ulceration, white-colored worm-like copepods protruding on different parts of the body and pale anemic or congested gills. Histopathological changes included vacuolation and necrosis of epidermal cells and hyperplasia and fusion of secondary gill lamellae. In addition to leucocytic cell infiltrations mainly lymphocytes and macrophages, hyperplasia of gill cartilage and parasitic cysts surrounded by several layers of fibroblast cells were noticed. In conclusion, the prevalence rate of parasite infection in goldfish is relatively high as well as the pathological findings induced by these parasites and might negatively affect the proper function of the skin and gills of the host. [ABSTRACT FROM AUTHOR]

Over the course of an approximately 11-month period, an outdoor, freshwater, mixed species, recirculating, display system at a public aquarium experienced intermittent mortalities of channel catfish (Ictalurus punctatus) and blue catfish (I. furcatus). Catfish acutely presented for abnormal buoyancy, coelomic distention, and protein-rich coelomic effusion. Gross lesions typically involved massive coelomic distension with protein-rich effusion, generalized edema, and gastric hemorrhage and edema. Microscopically, primary lesions included renal tubular necrosis, gastric edema with mucosal hemorrhages, and generalized edema. Aerobic culture and virus isolation could not recover a consistent infectious agent. Intracoelomic injection of coelomic effusion and aspirated retrobulbar fluid from a catfish into naïve zebrafish (bioassay) produced peracute mortality in 3 of 4 fish and nervous signs in the fourth compared with 2 saline-injected control zebrafish that had - no mortality or clinical signs. Kidney tissue and coelomic effusion were submitted for gas chromatography tandem mass spectrometry by multiple reaction monitoring against laboratory standards, which detected the presence of multiple pyrethroid toxins, including bioallethrin, bifenthrin, trans-permethrin, phenothrin, and deltamethrin. Detection of multiple pyrethroids presumably reflects multiple exposures with several products. As such, the contributions of each pyrethroid toward clinical presentation, lesion development, and disease pathogenesis cannot be determined, but they are suspected to have collectively resulted in disrupted osmoregulation and fluid overload due to renal injury. Pesticide-induced toxicoses involving aquarium fish are rarely reported with this being the first description of pyrethroid-induced lesions and mortality in public aquarium-held fish. [ABSTRACT FROM AUTHOR]

Simple Summary: To complement the genetic information of the pencilfish, a popular aquarium ornamental fish, we sequenced the mitochondrial genomes of four common pencilfish species. Their genome structure, nucleotide composition, codon usage, and phylogeny were comparatively analyzed. The results indicate that the four mitogenomes exhibited a typical circular structure. The gene order of the four Nannostomus pencilfish was similar to that of other fish. Our phylogenetic analyses support the current classification of the family Lebiasinidae. This study provides new data for the breeding and study of pencilfish. Although the pencilfish is a globally popular economic fish in the aquarium market, its taxonomic classification could be further refined. In order to understand the taxonomy of species of the genus Nannostomus (Characiformes, Lebiasinidae) and their phylogenetic position within the order Characiformes, in this study, we characterized mitochondrial genomes (mitogenomes) from four Nannostomus species for the first time. The four mitogenomes exhibited the typical circular structure, with overall sizes varying from 16,661 bp to 16,690 bp. They contained 13 protein-coding genes (PCGs), 2 ribosomal RNA genes (rRNAs), 22 transfer RNA genes (tRNAs), and 1 control region (CR). Nucleotide composition analysis suggested that the mitochondrial sequences were biased toward A and T. Bayesian inference and maximum likelihood analyses based on PCGs support the family Lebiasinidae classification, described using four Nannostomus species, clustering together with Lebiasina multimaculata from the same family. The results of this study support the current taxonomic classification of the family Lebiasinidae. Phylogenetic analysis also suggested that gene rearrangement would not significantly impact the phylogenetic relationships within the order Characiformes. These results might provide new data regarding the phylogeny and classification of the order Characiformes, thus providing a theoretical basis for the economic development of aquarium fish markets. [ABSTRACT FROM AUTHOR]

Captive fish populations, such as those encompassing aquarium and pet fish, offer significant economic value and are integral to conservation, research, and education. However, these ornamental fish exhibit a reduced ability to protect their ocular surfaces, and our understanding of the ocular diseases that affect them remains limited. Although corneal neoplasms in carp are uncommon, identifying their distinct characteristics is crucial in selecting appropriate therapeutic interventions that aim to preserve vision, prevent the ocular loss, and ultimately ensure the survival of the affected fish. This study provides clinical and histopathological details of various proliferative corneal masses in Cyprininae species, including five koi (Cyprinus carpio) and four goldfish (Carassius auratus). It discusses a spectrum of neoplasms, including soft tissue sarcoma, spindle cell sarcoma, chromatophoroma, and papilloma, in addition to conditions like exuberant granulation tissue and proliferative carp pox. These findings bear significant implications for clinical decision‐making and treatment, offering valuable insights into the incidence and characteristics of corneal tumors in captive fish, which could inform further studies in this area. [ABSTRACT FROM AUTHOR]

Background: Annual or seasonal killifishes (Cyprinodontiformes: Nothobranchiidae) are unique among fish in their ability to enter into developmental arrests (diapauses: DI, DII, and DIII). They have a short lifespan and their embryos are exceptionally tolerant to a variety of environmental stresses. These traits make them a popular model for studying vertebrate diapause, aging, stress tolerance, genome adaptation, and evolution. In such issues, in a comparative evolutionary framework, Fundulopanchax gardneri, a popular aquarium fish from Africa, is commonly used as a representative non‐annual model though its development is not studied in detail and whether it includes diapauses remains uncertain. Results: We described in detail for the first time embryonic development of F. gardneri and revealed it to resemble that in the undoubtedly annual Austrofundulus limnaeus killifish in displaying two developmental depressions. However, if compared with A. limnaeus, these developmental states look like "less intense" versions of DII and DIII rather than true diapauses. Conclusions: To determine whether developmental depressions in F. gardneri represent "true" diapauses or only their functional equivalents, detailed studies of embryonic development of different killifish both annual and non‐annual are needed. Before that, acceptance of F. gardneri as a representative non‐annual fish seems premature. Key Findings: Aplocheloid annual killifish (Cyprinodontiformes) are unique among fish in the ability to arrest development at different embryonic stages and prolong it for months and years. These and other traits make them a popular model in studying of aging, stress tolerance etc. In these studies, in a comparative framework, aplocheloid Fundulopanchax gardneri is usually used as a representative non‐annual fish though its developmental life‐history remains obscure.This study provides detailed description of F. gardneri development from early embryonic stages till sexual maturation with focus on developmental arrests, divergent developmental trajectories, duration of embryonic period, etc.The data provided in this study indicate F. gardneri to display developmental traits characteristic for annual killifish but in the "less expressed" form. Acceptance of F. gardneri as annual vs non‐annual is premature until the detailed study of embryonic development in other killifish both annual and non‐annual. [ABSTRACT FROM AUTHOR]

With 76 currently valid species, the bushynose catfish genus Ancistrus is the fourth most species‐rich catfish genus, yet Ancistrus diversity remains underestimated, with many species still undescribed. This is especially true of the Peruvian Andean headwaters of the Amazon, which are rich in unnamed Ancistrus species but have received little recent taxonomic attention. We describe a distinctively striped new Ancistrus species from tributaries of the Palcazú River, in the Pachitea‐Ucayali‐Amazonas drainage basin. The new species differs from all congeners by having black, vermiculated lines covering the head and two to four distinct black, parallel, lateral body stripes from head to caudal fin (vs. body uniformly colored or with dark or light spots or blotches over head and body, or black vermiculate lines on flanks). The new species is the fifth valid species of Ancistrus described from the rich Ucayali River ichthyofauna. It has previously been recognized in the aquarium fish trade as L267. [ABSTRACT FROM AUTHOR]

Objective: The White‐barred Goby Amblygobius phalaena is a popular ornamental fish in the marine aquarium market. To achieve successful commercial production, efficient larval rearing techniques are crucial. Previous studies have achieved successful cultivation of White‐barred Goby larvae by using a combination of three live feed organisms—the ciliate Euplotes sp., the rotifer Brachionus rotundiformis, and the copepod Apocyclops royi nauplii—during the first feeding stage. However, the specific contributions of these live feed organisms to larval survival and growth remain unclear. Moreover, the optimal feeding density for the critical initial live feed organism has not been determined experimentally. In this study, we aimed to enhance the larviculture protocol for White‐barred Goby by introducing Portuguese oyster Crassostrea angulata trochophores and by addressing these knowledge gaps. Methods: Larvae were initially cultured through individual and combined feeding with four live feed organisms: Euplotes sp., Portuguese oyster trochophores, B. rotundiformis, and A. royi nauplii. The objective was to identify the optimal initial live feed organism during the first feeding stage by assessing the survival and growth performance of larvae. Subsequently, using this optimal live feed organism, larvae were cultured at four feeding densities (2, 5, 10, and 20 individuals/mL). Through evaluating feeding incidence, feeding intensity, survival, and growth performance, the aim was to determine the optimal feeding density for the selected live prey. Result: Our experiments revealed that White‐barred Goby larvae could consume both oyster trochophores and Euplotes sp. during the first feeding stage. However, larvae exhibited superior survival and growth performance when fed oyster trochophores. The optimal feeding density of oyster trochophores was determined to be 10 individuals/mL, while a feeding density as high as 20 individuals/mL resulted in decreased larval feeding incidence. Conclusion: These findings have significant implications for enhancing larval production programs for marine ornamental gobies and promoting their sustainable commercialization. Impact statementOur study enhances the larval rearing of the popular marine ornamental fish, the White‐barred Goby. Feeding them with oyster trochophores at appropriate densities improves their survival and growth. This leads to more efficient commercial production, alleviating fishing pressure on wild populations. It marks a significant stride in preserving the diversity of coral reef fish and fostering a sustainable aquarium industry. [ABSTRACT FROM AUTHOR]

Three experiments were conducted examining whether an artificially selected "gold" color variant in female "models" affects mate choice copying behavior in sailfin mollies (Poecilia latipinna). Experiment I consisted of a pair of female preference assays, first assessing preference for male body size, followed by a mate choice copying assay that paired a model female with the smaller, non-preferred male from the initial preference test. Female subjects were divided into three groups that used either a wildtype female model, an artificially selected "gold" variant (cultivated within the aquarium fish trade) model, or control wherein no model was presented. Results showed females consistently copied the model's choice, switching preferences from the larger to smaller male when paired with a model regardless of color. In the second experiment wildtype females were presented with a pair of size-matched dummy males both of which paired with model females (one gold and the other wild type). Subjects consistently preferred the male previously paired with the gold- over the male with the wildtype-model, suggesting pre-existing sensory/perceptual biases may have affected their mate choice copying behavior. Previous studies have offered evidence for the spread of novel traits in males via sensory exploitation. However, these results indicate such biases may influence courtship behavior in circumstances where the novel trait is expressed in females as well. For the third experiment, wildtype females were presented with a choice between gold vs wildtype dummy males, the results of which revealing significant preferences for gold. In a follow-up assay pairing a wild type model with the non-preferred wildtype male, females maintained their preference for gold males despite the conflicting social driver of mate choice copying. These data offer evidence for the existence of a perceptual/cognitive bias in the context of mate choice copying, favoring the gold phenotype and/or novelty in general. [ABSTRACT FROM AUTHOR]

Bottom-feeding fish can exert strong top-down pressure on benthic invertebrates while also causing mechanical disturbance of the sediment. In our laboratory study, we investigated the influence of predation and disturbance-induced water column emigration on meiofauna, triggered by the armored catfish Corydoras aeneus. We hypothesized that both factors would significantly reduce the abundance of meiofauna, depending on their body size. Accordingly, we also expected a change in the nematode community structure. After 24 h, the abundances of nematodes, tardigrades, hydracarina, copepods and oligochaetes were significantly lower than in control aquariums without fish, in the latter two groups primarily due to predation. All other taxa were equally affected by predation and emigration. Within the nematodes, mainly large individuals (≥ 1 mm) were consumed, while smaller worms (< 1 mm) were increasingly dispersed. This, though it did not reduce species numbers, resulted in altered size and species composition. Our results show that the real top-down effects can quickly be overestimated as emigration of prey is overlooked and, on the other hand, that fish may also influence adjacent, undisturbed areas due to subsequent immigration of meiofauna. [ABSTRACT FROM AUTHOR]

Copyright of Kocatepe Veterinary Journal / Kocatepe Veteriner Dergisi is the property of Afyon Kocatepe University, Faculty of Veterinary Medicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: The ever-increasing popularity of home aquariums, most often involving freshwater varieties, has exploded in recent years partially due to the Coronavirus pandemic and related to stay-at-home public health precautions for social distancing. With this ever-increasing popularity of aquariums as a hobby, and whether this involves freshwater or marine fish species, a number of important economic, ecological, and public health issues arise for both fish and hobbyists alike. Materials and Methods: This review highlights the history and genesis of aquariums as both a hobby and an important economic factor (industrial, commercial) for many countries on a global basis. Types of aquarium fish are described, and culture conditions leading to homeostasis in aquatic environments are detailed. When these conditions are not met and aquatic systems are out of balance, the disease can result due to stressed fish. Results: Major bacterial diseases associated with freshwater aquarium fish are reviewed, as are potential human infections related to the care and maintenance of home aquaria. Conclusion: Besides, scientific information was also combined with the false facts of hobbyists who tried to identify and treat diseases during an outbreak in the aquarium. Finally, unresolved issues and important misconceptions regarding the field are discussed. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Threatened Taxa is the property of Wildlife Information Liaison Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Integrated fish and livestock farming is an ancient practice and is used to increase production per unit area and reduce the environmental impact caused by untreated animal excreta. Although integrated aquaculture has been used in some countries, including Brazil, this practice has declined. However, many pig farmers maintain their ponds and/or have rivers near their pig farms, allowing raw manure to drain to them. The objective of this work was to verify the possibility of infection of fish by porcine circovirus 2 (PCV2) and, thus, serving as a reservoir species. Eleven specimens of Nile tilapia (Oreochromis niloticus), negative for PCV2, were inoculated with PCV2 intramuscularly and observed for 61 d post-inoculation (dpi), when they were euthanized and had their intestines, livers and gills removed to evaluate for presence of PCV2. The faeces were collected directly from the fish aquarium every four days up to 12 dpi and then once a week up to 61 dpi. The organs and faeces were tested by qualitative polymerase chain reaction (qPCR) for PCV2. This preliminary study showed that PCV2 inoculation was successful in infecting fish. In addition, PCV2 was eliminated in the faeces intermittently during the 61 d of experimentation. [ABSTRACT FROM AUTHOR]

The freshwater calanoid copepod Arctodiaptomus dorsalis (Marsh, 1907) was first recorded from the Philippines in 2001 in Laguna de BayThe copepod gained the status of "invasive species" in 2021 due to its presence in 23 of 32 surveyed Philippine lakes and rivers. Genomic DNA was extracted from 107 individuals of A. dorsalis , representing seven populations on the island of Luzon to gather information on the population structure, genetic connectivity, and range expansion of the species.. A 720-bp fragment of the nuclear ITS1 and ITS2 spacers was used to analyze the genetic structure of the populations. High haplotype diversity (Hd = 0.7951), low nucleotide diversity (π = 0.0024), and low genetic distance between populations indicate high levels of gene flow and low levels of isolation. Six of the 12 haplotypes were unique to particular sites, but the three shared haplotypes suggest panmixia among populations. Tajima's D (D = 0.4945) and Fu's F (F = -2.8950) suggest a recent increase in population size following a bottleneck. This may have occurred as the result of the copepod's suspected initial introduction into the Philippines after 1905 via the trade in ornamental aquarium fish, eventually followed by its expansion into nearby inland waters through one or more aquaculture-mediated introduction events. Laguna de Bay's role since 1972 as the main source of tilapia fingerlings (Oreochromis niloticus (Linnaeus, 1758)) for release into various Philippine lakes provides circumstantial support for this scenario. [ABSTRACT FROM AUTHOR]

Network interpretation illuminates our understanding of the dynamic nature of cultural evolution. Guided by cultural evolution theory, this article explores how people collectively develop knowledge through knowledge collaboration network traits. Using network data from 910 artifacts (the WikiProject Aquarium Fishes articles) over 163 weeks, two studies were designed to understand how collaboration network traits drive population and artifact-level knowledge evolution. The first study examines the selection pressure imposed by10 network traits (against 11 content traits) on population-level evolutionary outcomes. While network traits are vital in identifying natural selection pressure, intriguingly, no significant difference was found between network traits and content traits, challenging a recent theory on network-driven evolution. The second study utilizes time series analysis to reveal that three network traits (embeddedness, connectivity, and redundancy) at a prior time predict future artifact development trajectory. This implies that people collectively explore various positions in a potential solution space, suggesting content exploration as a possible explanation of knowledge evolution. In summary, understanding the interplay between network traits and content exploration provides valuable insights into the mechanisms driving knowledge evolution and offers new avenues for future research. [ABSTRACT FROM AUTHOR]

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

Waste produced from aquaculture ultimately hampered the water quality and growth performance of species cultured. Therefore, the potential exploitation of photosynthetic bacteria (PSB) from aquaculture waste was investigated to treat the wastewater in the fish culture. In this study, the wastewater was collected from a fishpond and cultured in sunlight-exposed sterile bottles for 14 days. In the water additive experiment, five treatments (in a 30 cm3 aquarium) were prepared namely cultured PSB (T1), aquatic plant hornwort (T2), aquatic plant salvinia (T3), positive control (P), and negative control (N). Five individuals of Hyphessobrycon herbertaxelrodi (2.5±0.5 cm length) were placed in each treatment and reared for 30 days. Meanwhile, for the wastewater treatment, four treatments (in a 30 cm3 aquarium) were prepared namely wastewater from the hatchery fishpond (S1), wastewater from the hatchery fish tank (S2), positive control (P), and negative control (N). The results obtained indicate that T1 treatment significantly improved and maintained the water quality as compared to other treatments. The results showed the amount of ammonia and nitrite in S1 and S2 supplied with T1 for 30 days gradually decreased from day 1 until day 18. While zero amount of ammonia and nitrate was acquired from day 21 until day 30 of the wastewater experiment. The treatment with PSB showcased the bacteria's ability to utilize and absorb nutrients, thereby maintaining and improving water quality. The potential use of beneficial bacteria in the culture system can accelerate the nitrogen cycle for a sustainable way of wastewater management. [ABSTRACT FROM AUTHOR]

This study was aimed to evaluate the effect of sublethal concentrations of lead chloride on physiological and histopathological studies in Gambusia affinis . A total of 500 fish were collected from the bank of the river east of Mosul city. The fish in the aquarium were divided into five groups (control, acute exposure(20,25mg/l) and chronic exposure(5,10mg/l)). The bioaccumulation of lead in acute and chronic periods of exposure showed a significant difference in values between control and treatment. The greatest level was seen in the kidney of fish treated with lead dichloride at 10 mg/l for 30 days. The level of antioxidant Glutathione has a significant decrease in different kidneys of fish treated with pbcl2 exposed to acute and chronic concentrations. The lowest decrease was seen in kidneys of fish treated with Pbcl2 at 10 mg/l for a month. At the same time, a significant increase in lipid peroxidation (malondialdehyde) level was seen in all kidney treated with pbcl2. Histological study of the kidney showed varying degrees of pathological lesions. The glomeruli in the kidney shrank, and degeneration of Bowman's capsule. The Pb accumulation increases with increasing concentration and period of exposure. Both acute and chronic effects caused a change in the level of antioxidants and histopathological changes in kidney of the fish. Histopathological study may be a useful indicator for determining the extent of aquatic contamination. It could be concluded that the kidney changes caused by lead exposures in fish may serve as a biomarker for the contamination of sub-lethal levels of heavy metals and other anthropogenic contaminants. [ABSTRACT FROM AUTHOR]

Pet abandonment is an important introduction vector for freshwater aquarium fishes, as unwanted pets become too large for tank dimensions and are released into the environment. Concerns over pet abandonment may be particularly important for the U.S. state of Florida, which exhibits abundant access to freshwater habitats and a climate more favorable to tropical aquarium fishes than other continental U.S. states. Numerous studies have examined the factors affecting establishment for non-native species, including the importance of propagule pressure and climate suitability. For freshwater aquarium species, maximum body size can increase pet abandonment because they grow too large for the tank dimensions (i.e., "tankbusters"). Thus, large maximum body size may increase propagule pressure due to intentional release. In addition to being introduced in sufficient numbers, a match between the thermal tolerance of a species and the thermal habitat is necessary for establishment. Several large-bodied catfishes are found in the aquarium trade, including the goonch Bagarius spp., redtail catfish Phractocephalus hemioliopterus, and tiger sorubim Pseudoplatystoma tigrinum. Here, we experimentally determined the chronic lethal minimum temperature (CLmin) for the three catfishes. CLMin estimates for these three species were higher than many other ornamental species, highest for the redtail catfish (14.3 °C), lower for the tiger sorubim (11.0 °C), and lowest (9.9 °C) for the goonch. Given these lethal temperatures, the distribution of redtail catfish would be limited to South Florida while the tiger sorubim and goonch could live, provided other habitat characteristics are suitable, up to -28°N Latitude in Florida. [ABSTRACT FROM AUTHOR]

The North American western mosquitofish, Gambusia affinis (Baird and Girard, 1853), has been introduced into a number of countries around the world, primarily for the control of mosquito populations. Gambusia affinis is known to harbour several monogenean parasites, which have the potential to be co-introduced to new regions. However, despite the broad non-native distribution of this fish species, their monogenean parasites have been reported from a relatively small number of locations. Parasitological investigations have identified very few freshwater monogenean parasites from freshwater fish in New Zealand. Two monogenean parasites were recorded infesting G. affinis in New Zealand; Salsuginus seculus (Mizelle and Arcadi, 1945) (a new genus to New Zealand) on the gills and Gyrodactlyus gambusiae Rogers and Welborn, 1965, on the gills and surface of the fish. Despite the broad distribution of G. affinis, S. seculus and G. gambusiae have been reported in few countries due, perhaps, to lack of research effort on monogeneans, their small size, enemy-release, or a combination of these factors. Based on the diversity of monogeneans in other countries that are found associated with fish with non-native populations in New Zealand, it is likely that many unrecognised non-native monogeneans are established in New Zealand's freshwater ecosystems alongside their fish hosts. Further, the number of introduced monogeneans is likely to be even higher than is currently appreciated when considering non-native fish in the aquarium trade and other introduced freshwater fauna, such as terrapins. [ABSTRACT FROM AUTHOR]

We investigated the effectiveness of TiO2 cenospheres in reducing the concentrations of three common harmful compounds, ammonium, nitrate, and nitrite, in fish aquariums. These cenospheres can contribute to more sustainable and eco-friendly aquarium filtration systems while also improving the health of fish. We designed a 30-day experiment with three treatment groups based on the filter type: (1) a control group with a conventional aquarium filter, (2) a group with a TiO2 cenosphere filter, and (3) a group with a dark TiO2 cenosphere filter. The water quality was the same baseline in all groups, and each tank was monitored daily for changes in temperature, pH, ammonia, nitrate, and nitrite concentrations. We found that the TiO2 cenosphere filter was effective in reducing the concentrations of all three pollutants. By the end of the experimental period, the average concentration of nitrite in the control group was 10.7 µM, while the average concentration in the TiO2 cenosphere filter group dropped 55% to 4.7 µM from the baseline. The average concentration of nitrate was reduced by 17% and ammonia by 28% in the cenosphere-treated group. Hence, the cenospheres were effective in reducing the concentrations of all three pollutants, with the greatest reduction seen for nitrite. These findings support further investigation for incorporating TiO2 cenospheres into aquarium filtration to help reduce the environmental burden of the aquarium industry. [ABSTRACT FROM AUTHOR]

Amoebae of the genus Vannella isolated from an ornamental fish aquarium were found to be infected with fungi. Upon plate culture, amoeba-trapping hyphal filaments were developed, and the amoeba trophozoites were found to harbour yeast-like parasites in their cytoplasm. Transfection of hyphae to a laboratory strain of Vannella resulted in the formation of conidia indicating the possible presence of zygomycetes of the genus Acaulopage, while efforts to culture the endoparasite remained unsuccessful. Biomolecular analysis based on rDNA revealed the presence of two distinct types of fungi, confirming the filamentous form as Acaulopage sp. (Zoopagomycota, Zoopagales) and identifying the yeast-like endoparasite as Cladosporium sp. (Ascomycota, Cladosporiales). To our knowledge, this is the first report of amoebae infected with Cladosporium. [ABSTRACT FROM AUTHOR]

Terms such as leader, mediator, and follower sound equal in the description of a pack of wolves, a street protest crowd, or a business team and have very similar meanings. This indicates the presence of some general law or structure that governs collective behaviour. To reveal this, we selected the most common parameter for most levels of the organisation—motion. A causality analysis of distance correlations was performed to obtain follow-up networks that show who follows whom and how strongly. These networks characterise an observed system in general and work as an automation bridge between the biological experiment and the broad field of network analysis. The proposed method was tested on 3D image data from a controlled experiment on a 6-member school of aquarium fish of Tiger Barb. The network patterns can be easily ethologically interpreted and agreed with expected behaviour. [ABSTRACT FROM AUTHOR]

The current study was aimed to evaluate the effect of Zn and Cu in the gills, kidney, liver and muscle of Channa punctata. Fish samples (average wet body weight 460.77 ± 6.22 g) were collected from the freshwater reservoir. The heavy metals were assessed through atomic absorption. Model mixtures were prepared in aquarium and fish were treated with that. The findings of this study revealed bioaccumulation of metals. The heavy metals concentration was crossing the permissible limits suggested by WHO. Histopathological examination in kidney exhibited congestion, dilation in bowman capsule space, necrosis. Liver of the fish exhibited cytoplasmic vacuolation, necrosis, sinusoid dilation. It has been concluded that this lake is heavily contaminated due to the discharge of untreated waste from industry and domestic sewage from the city and there is a dire need to control this increasing contamination. [ABSTRACT FROM AUTHOR]

More than 10 y have passed since the Fukushima Dai-ichi Nuclear Power Plant (F1-NPP) accident, but there are still many areas with high levels of radioactive contamination, especially reservoirs and lakes, where the levels decrease slowly. The exposed dose to non-human biota is of great concern. In this work, the exposure dose to wild medaka (small aquarium fish) around F1-NPP was measured/estimated by two approaches: in situ measurement and with the ERICA assessment tool. S2 is a reservoir located 7.5 km from F1-NPP, and the ambient dose rate was 25.0 μSv per h in 2012, but decreased to 4.82 μSv per h in 2021. The external exposure dose rate to wild medaka living there was 0.8–11.8 μGy per h (2017–21) by in situ measurement, and the estimated dose rate with the ERICA assessment tool was 0.6–54.5 μGy per h (2012–21). The estimated and measured doses to wild medaka are not expected to cause any significant radiation effects. [ABSTRACT FROM AUTHOR]

The tribe Hemichromini is an early diverging, mainly Central and West African lineage within the species-rich African cichlid fishes (Cichliformes, Cichlidae) including two genera, Hemichromis Peters 1858 and the monotypic Anomalochromis Greenwood 1985. Though many of the species are popular aquarium fish, the number of hemichromine species is still a matter of debate with their phylogenetic relationships largely unknown. Based on DNA sequence data of two mitochondrial and two nuclear genes, we present the first comprehensive phylogeny of the Hemichromini. Using an integrative approach based on these DNA sequences data, morphometrics, meristics, and a qualitative assessment of body coloration, we revise the genus Hemichromis and discuss intrageneric relationships. Two major groups within the genus Hemichromis that diverged roughly 6–12 MYA are recognized, of which the first one represents Hemichromis sensu stricto, for the second one a new genus, Rubricatochromis, is described. Diversification with these two main groups started about 3–6 MYA, with different trajectories of colonization in the two groups. Hemichromis populations from the most southern (Cuanza, Zambezi, and Okavango) part of the genus' distribution range constitute a well-supported clade distinct from all other members of Hemichromis, for which the taxon H. angolensis Steindachner, 1865 is confirmed. [ABSTRACT FROM AUTHOR]

We used a combination of morphological, molecular and biological data to characterize a novel Henneguya (Myxozoa) species infecting the Amazonian prochilodontid Semaprochilodus insignis or "kissing prochilodus", a popular food fish and aquarium species in the Brazilian Amazon. Twenty-one S. insignis were caught live from the Tapajós river, Pará State, Brazil, then examined for myxozoan infections. Cysts of a novel Henneguya species were observed in the connective tissue of the fins. Myxospores measured 48 ± 4.9 (39.5–60.8) µm total length, of which caudal appendages were 33 ± 4.5 (26.4–45.2) µm and spore body was 15 ± 1.6 (12.4–20.5) µm. The spore body was 4.0 ± 0.6 (2.7–5.3) µm wide × 3.2 ± 0.4 (2.7–3.6) µm thick, with two unequal polar capsules (nematocysts) 7.2 ±0.8 (5.2–8.3) × 1.5 ± 0.3 (1.0–2.2) µm for the larger capsule and 5 ± 0.7 (4.0–6.3) × 1.4 ± 0.2 (1.0–1.8) µm for the smaller capsule. Polar tubules had 8–13 turns. Generative cells, immature and mature myxospores were observed within plasmodia. Ultrastructure showed plasmodia surrounded by collagen fibers, with the plasmodial membrane having pinocytotic channels. Phylogenetic analysis of small subunit ribosomal DNA sequences showed that the new Henneguya species clustered as a sister taxon to Henneguya tietensis, a parasite of the gills of the prochilodontid fish Prochilodus lineatus, from the geographically distant Paraná–Paraguai River basin. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the effect of humic acid (HA) obtained by extraction from alginate on the incubation of roes and fry development in African cichlids, Labidochormis caeruleus, as well as their influence on the stabilization of the physicochemical parameters of water in an aquarium during artificial breeding. The roes were obtained by extruding from a female buccal cavity immediately after fertilization. For the experiment, 4 groups of 40 roes were formed in an incubator with an artificial hatchery. Groups 1–3 were exposed to 1%, 5%, and 10% concentrations of HA, respectively. The control group C was not exposed to HA. In all groups, the mortality and size differences of the fry, as well as the temperature, pH, hardness, nitrite, and nitrate levels in the tanks, were determined during a 30-day monitoring period until the resorption of the yolk sac. The results of this study indicated the ability of HA in 5% and 10% concentrations to reduce nitrite and nitrate levels in the aquatic environment, which significantly reduced the mortality of roes and the survivability of the fry. The determination of the morphological measurements of the fry revealed an increased body length in the groups exposed to 5% and 10% HA concentrations compared to the control group by the end of the monitored period. It was also noted that the yolk sac was resorbed two days earlier in the same groups than in the control. Thus, the results showed that HAs are suitable for use in the artificial aquarium incubation of roes and fry development, which are increasingly exposed to adverse environmental factors. The knowledge obtained in this study and its transfer into practice can allow even less experienced aquarists to successfully breed aquarium fish species that could not normally be bred under artificial conditions without the addition of HA. [ABSTRACT FROM AUTHOR]

Popular as aquarium fish, armored catfishes from South America (Pterygoplichthys spp.) have been introduced and become invasive in tropical and subtropical regions worldwide. These ecosystem engineers can deplete basal resources (e.g., periphyton and detritus), with potential negative effects for native fauna. We studied the trophic ecology of fishes in the Usumacinta River Basin, Guatemala, where Pterygoplichthys is now widespread and locally abundant. We analyzed stable isotopes (δ13C, δ15N) in fish tissues and basal resources to assess the potential impact of Pterygoplichthys on the trophic ecology of six co‐occurring native fishes that feed at a similar trophic level (Astyanax aeneus, Dorosoma petenense, Thorichthys pasionis, Oscura heterospila, Poecilia mexicana, and Gambusia sexradiata). The study was conducted during the dry season in the La Pasion (LPR; high invasion) and San Pedro (SPR; low invasion) rivers. We compared isotopic spaces occupied by native fish and Pterygoplichthys, estimated isotopic overlap, and evaluated the trophic displacement of native species. We also evaluated the relationships of environmental factors, including the relative biomass of the invasive catfish, with δ13C and δ15N signatures. Except for P. mexicana, native species had lower isotopic overlap with the catfish in LPR. Native fish isotopic spaces were compressed and shifted toward higher trophic positions in LPR relative to SPR. Benthic food resources were important for Pterygoplichthys in both rivers, and water‐column resources had greater relative importance (RI) for native species in LPR. Native fish δ13C was significantly associated with Pterygoplichthys biomass, conductivity, and water flow velocity; and water depth and sedimentation had a significant association with native fish δ15N. Findings provide evidence that invasive Pterygoplichthys, along with environmental factors, impact the trophic ecology of native fish in the Usumacinta Basin. Additional field research conducted over longer time periods and mesocosm experiments that account for fish assemblage and environmental variation could elucidate Pterygoplichthys impacts via food resource depletion or habitat alteration. [ABSTRACT FROM AUTHOR]

Risk analyses for invasive species often assume that the characteristics of future invaders will resemble those already successful, but these features may change.Here, we use data from more than 3,500 fish sampling events, sequencing of mitochondrial and nuclear genes and analyses of several traits describing non‐native fish to describe the irruption and rapid expansion of non‐native loaches in Catalonia, north‐east Iberian Peninsula, and framing this surge in the knowledge of previous invasions.We report the establishment of at least five (Cobitis bilineata, Misgurnus anguillicaudatus, Misgurnus bipartitus, Paramisgurnus dabryanus, and a yet undescribed Barbatula species) non‐native loach species in Catalonia, most of which are currently spreading. Furthermore, one of the two regionally native loach species (Cobitis paludica) has been introduced and is spreading through river basins where it is not native.Genetic analyses were fundamental to understand loach invasions, by clarifying specific statuses, identifying the origin of non‐native populations and/or detecting independent introduction events. Genetic results also highlighted the unresolved taxonomy of loaches, particularly for European Barbatula.Loaches are recent, diverse, and successful invaders whose traits differ from those of most previously established invasive fish species, signalling potential weaknesses of prevention of biological invasions based on prohibited species lists. We call for the development of more flexible management tools (e.g. based on fish traits and not only on species identities) and prioritising prevention and rapid responses to new introductions. [ABSTRACT FROM AUTHOR]

This document is a correction notice for a journal article titled "Effects of microplastic exposure on the body condition and behaviour of planktivorous reef fish (Acanthochromis polyacanthus)." The correction addresses errors in the density values and sentences in the methods section of the article. The corrected figures and sentences are provided in the notice. Additionally, there is an error in the supporting information file, which is also corrected. The correction notice is authored by Kay Critchell and Mia O. Hoogenboom. [Extracted from the article]

This article reports a case of Mycobacterium interjectum infection in a 48-year-old man who had been in contact with aquarium fish. The patient presented with nodular lesions on his hand and forearm, and a biopsy confirmed the presence of the bacteria. Treatment with a combination of rifampicin, clarithromycin, and co-trimoxazole for 9 months resulted in some resolution of the lesions. Mycobacterium interjectum is a rare mycobacteria that can cause infections in both immunocompromised and immunocompetent individuals, and it has been found in water, soil, and aquarium fish. [Extracted from the article]

Nutrient runoff is a major water quality issue affecting water resources. Excess nutrients such as nitrate (NO3−) and phosphate (PO43−) entering surface waters promote eutrophication. Recent research showed that floating treatment wetlands combined with slow-release lanthanum composites deployed through airlift pumps can reduce NO3− and PO43− concentrations, minimize algae and weeds, and increase dissolved oxygen concentrations. While water quality improves following this biological and chemical approach, questions remain about the toxicity and potential accumulation of lanthanum in lentic organisms. We addressed this concern by analyzing flesh and liver of fish exposed to the slow-release lanthanum following two years of treatment and compared results to fish harvested from a control, untreated pond. We also conducted an aquarium fish study that used higher lanthanum concentrations than those observed in the field. The field study confirmed that under the concentrations of lanthanum released to treat eutrophic ponds (109 µg L−1), no adverse effects were observed in harvested fish. We also observed no significant differences between lanthanum-exposed and -unexposed fish (α = 0.05) in our controlled tank study. Given the laboratory tank lanthanum concentrations were approximately nine times higher (916 µg L−1) than the observed field concentrations, we conclude the slow-release lanthanum composites used to treat eutrophic ponds are effective in improving water quality and do not lead to significant lanthanum accumulation in fish. [ABSTRACT FROM AUTHOR]

An indirect human health risk assessment was conducted on four lines of genetically modified Tiger Barbs (Puntigrus tetrazona) known as the GloFish® Electric Green® Barb (GB2011), GloFish® Starfire Red® Barb (RB2015), GloFish® Sunburst Orange® Barb (OB2019), and the GloFish® Galactic Purple® Barb (PB2019) that were notified under the Canadian Environmental Protection Act (CEPA). GB2011, RB2015, OB2019, and PB2019 are modified lines of diploid, hemizygous or homozygous Tiger Barbs, containing genes encoding for different fluorescent proteins. GB2011, RB2015, OB2019, and PB2019 appear green, red, orange, or purple, respectively, under ambient light (including sunlight). The four lines will be imported from the United States for use as ornamental fish in home aquaria. This risk assessment examined the potential for the four lines to cause harmful effects to humans in Canada relative to wild-type Tiger Barbs as a consequence of environmental exposure including under its intended use in home aquaria. The parental strain, P. tetrazona, has been available as a home aquarium fish since the 1950s without any reported adverse human health effects. There is no evidence to suggest a risk of adverse human health effects for the general Canadian population from use of GB2011, RB2015, OB2019, and PB2019 as ornamental aquarium fish as well as other identified potential uses. As such, there is no expectation that GB2011, RB2015, OB2019, and PB2019 will pose any more risks to human health than wild-type P. tetrazona. [ABSTRACT FROM AUTHOR]

Guppy - Poecilia reticulata, an exotic species, is recorded from a natural freshwater in Hormuz basin, which shows the range extension of the fish to southern Iran. This fish was probably introduced as an aquarium fish, but seems it is established in Sabz-poushan Spring. This study also describes the length-weight relationship (LWR) for the 13 caught specimens of the fish. The length-weight parameter b for this species was 3.01 with a high regression coefficients (r² > 0.95). [ABSTRACT FROM AUTHOR]

This paper aims to show the importance of aquariology to human health, and the importance of Poeciliid fishes to aquarium science, aquariology and the aquarium trade. The aquarium hobby can have a range of positive effects on mental, emotional, and even physical well-being. It provides a unique blend of entertainment, education, and therapeutic benefits for individuals across different age groups. The diversity and genetic plasticity of Poeciliid fish have significantly shaped the aquarium hobby and market. Their vibrant colors, ease of breeding, and adaptability have made them appealing to a broad range of hobbyists, contributing to the growth, diversity, and commercial success of the aquarium industry. The potential for Poeciliids to become invasive highlights the importance of responsible pet ownership and the proper disposal of unwanted aquarium fish. Releasing non-native species into the wild can have significant ecological consequences and is generally discouraged to protect the integrity of natural ecosystems. Ultimately, ethical considerations in keeping animals in aquariums revolve around balancing the educational, conservation, and entertainment aspects with the welfare and conservation needs of the animals involved. Transparent practices, education, and ongoing efforts to improve standards contribute to the ethical evolution of the aquarium industry. [ABSTRACT FROM AUTHOR]

This study catalogued ocular pathology in fish histopathology submissions to a specialist diagnostic service and investigated associations with species and systemic disease, with a focus on species of conservation interest. Cross-tabulations and Fisher's exact tests were used to identify associations among the variables and results are reported as prevalence ratios (PRs) with 95% confidence intervals (CI). Of 12,488 reports reviewed, ocular histology examination was available for 4,572 submissions, in which histopathological ocular lesions were identified in 18% (813/4572). Most diagnoses (701/813; 87%) were in marine fish. Inflammatory conditions were most common (608/813; 75%), with identification of a bacterial aetiology in 42% (255/608) and a parasitic aetiology in 30% (183/608). Most bacterial infections were due to mycobacteriosis (153/255; 60%) and most parasitic infections were due to scuticociliatosis (114/184; 62%). The Syngnathidae, Centriscidae and Cichlidae families were each more likely than all other families combined to be diagnosed with ocular manifestations of mycobacteriosis (PRs = 2.6, 4.4 and 2.9, respectively, P <0.0001 for each). The Syngnathidae were also more likely to be diagnosed with ocular scuticociliatosis (PR = 1.9, P <0.0001). Fifty-four percent (39/72) of ocular mycobacteriosis and 38% (9/24) of gas bubble disease cases affected threatened or near threatened Syngnathidae species. The Apogonidae were more likely than any other family to have ocular iridovirus (PR = 10.3, 95% CI = 5.5–19.4, P <0.0001) and neoplasia (PR = 8.2, 95% CI = 4.2–16.3, P <0.0001). The endangered Banggai cardinalfish (Pterapogon kauderni) accounted for 13/15 ocular iridovirus and 16/18 mycobacteriosis cases in this family. All cases of neoplasia in the Apogonidae occurred in pajama cardinalfish (Sphaeramia nematoptera). These results should inform clinical diagnosis of ocular disease in aquarium fish and influence training for aquarists, highlighting ocular pathology as a potential early warning of systemic disease. The findings also have direct/indirect consequences for the welfare and conservation of some of these popular flagship fish species. Eye lesions such as exophthalmos are common and clinically obvious in fish and this study seeks to highlight the wide range of primary ocular disorders and underlying systemic disease processes identified in a large cohort of aquarium fish through the use of routine histopathological surveillance. [Display omitted] [ABSTRACT FROM AUTHOR]

Sri Lanka, one of the world's biological hotspots, exports wild-caught and farm-bred aquarium fish species to more than 70 countries. This study evaluated the potential for invasiveness of aquarium fish species now raised and traded in Sri Lanka's Gampaha, Kandy, and Polonnaruwa districts. A questionnaire survey of 40 hobbyists, 20 retailers and ten breeders of aquarium fish in each selected district was conducted to assess the causes of aquarium fish releases. The invasion potential was evaluated using a model consisting of species thermal tolerance, propagule pressure and invasion history. Overall, 59 non-native fish species belonging to 14 families (Acanthuridae, Callichthyidae, Characidae, Cichlidae, Cyprinidae, Helostomatidae, Loricariidae, Notopteridae, Pimelodidae, Poeciliidae, Osphronemidae, Osteoglossidae, Salmonidae, and Scombridae) were recorded from the aquarium trade in the country. Out of 17 species with high to moderate invasive potential, six have already been established in the environment in Sri Lanka. Therefore, Astronotus ocellatus, Barbonymus schwanenfeldii, Carassius auratus, Hypostomus plecostomus, Pangasianodon hypophthalmus, Poecilia latipinna, P. sphenops, Puntigrus tetrazona, Trichopodus microlepis, Xiphophorus helleri, and X. maculatus are identified as potential invaders in Sri Lanka. The reasons for the intentional release of aquarium fish into the environment were excessively large size, aggressiveness, diseases and high reproductive rates. The number of fish of each species released into the natural environment is positively correlated to the number kept in home aquaria. A well-coordinated institutional mechanism to control unwanted fish introductions through the aquarium fish trade in Sri Lanka is urgently needed. [ABSTRACT FROM AUTHOR]

An 8‐week feeding trial was conducted to determine the optimal dietary protein requirement for tinfoil barb (Barbonymus schwanenfeldii) fry. Six isocaloric practical test diets (17 kJ g−1 gross energy) were formulated to contain 25%, 30%, 35%, 40%, 45% and 50% protein. Fry (0.40 ± 0.03 g) were randomly stocked in eighteen 60 L glass aquaria at 25 fish per aquarium. Each aquarium was fitted with an individual recirculation system. Each test diet was randomly assigned to three aquaria (triplicates), and the fish were fed twice a day until satiation. The results showed that survival was not significantly affected by the protein level. Weight gain was significantly higher at 50% dietary protein compared with those of lower levels. Fish fed with 50% protein also showed a significantly higher (p < 0.05) specific growth rate than fish fed with 25%–40% protein. Feed efficiency improved with the increase in dietary protein level. Feed conversion ratio (FCR) was 1.29 when fry were fed 50% dietary protein, whereas fry fed 25%–35% protein had FCR of 1.7–2.0. No histopathologic changes in the liver and intestine were observed among all dietary treatments. The results indicated that tinfoil barb fry required a high 50% protein for best growth performance and feed efficiency. [ABSTRACT FROM AUTHOR]