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Ornamental Fish (ornamental + fish)
Selected AbstractsIsolation and selection of Bacillus spp. as potential biological agents for enhancement of water quality in culture of ornamental fishJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2007R. Lalloo Abstract Aims:, To isolate, select and evaluate Bacillus spp. as potential biological agents for enhancement of water quality in culture of ornamental fish. Methods and Results:, Natural isolates obtained from mud sediment and Cyprinus carpio were purified and assessed in vitro for efficacy based on the inhibition of growth of pathogenic Aeromonas hydrophila and the decrease in concentrations of ammonium, nitrite, nitrate and phosphate ions. Based on suitability to predefined characteristics, the isolates B001, B002 and B003 were selected and evaluated in vitro in the presence of Aer. hydrophila and in a preliminary in vivo trial with C. carpio. The inhibitory effect on pathogen growth and the decrease in concentrations of waste ions was demonstrated. Based on 16S RNA sequence homology, the isolates were identified as Bacillus subtilis, Bacillus cereus and Bacillus licheniformis, respectively. Isolate B002 did not contain the anthrax virulence plasmids pOX1, pOX2 or the B. cereus enterotoxin. Conclusions:, Selected isolates effected synergistic reduction in pathogen load and the concentrations of waste ions in vitro and in vivo and are safe for use in ornamental aquaculture. Significance and Impact of the Study:, A new approach for assessment of biological agents was demonstrated and has yielded putative isolates for development into aquaculture products. [source] Iridovirus infections in finfish , critical review with emphasis on ranavirusesJOURNAL OF FISH DISEASES, Issue 2 2010R J Whittington Abstract Viruses in three genera of the family Iridoviridae (iridoviruses) affect finfish. Ranaviruses and megalocytiviruses are recently emerged pathogens. Both cause severe systemic disease, occur globally and affect a diversity of hosts. In contrast, lymphocystiviruses cause superficial lesions and rarely cause economic loss. The ranavirus epizootic haematopoietic necrosis virus (EHNV) from Australia was the first iridovirus to cause epizootic mortality in finfish. Like other ranaviruses, it lacks host specificity. A distinct but closely related virus, European catfish virus, occurs in finfish in Europe, while very similar ranaviruses occur in amphibians in Europe, Asia, Australia, North America and South America. These viruses can be distinguished from one another by conserved differences in the sequence of the major capsid protein gene, which informs policies of the World Organisation for Animal Health to minimize transboundary spread of these agents. However, limited epidemiological information and variations in disease expression create difficulties for design of sampling strategies for surveillance. There is still uncertainty surrounding the taxonomy of some putative ranaviruses such as Singapore grouper iridovirus and Santee-Cooper ranavirus, both of which cause serious disease in fish, and confusion continues with diseases caused by megalocytiviruses. In this review, aspects of the agents and diseases caused by ranaviruses are contrasted with those due to megalocytiviruses to promote accurate diagnosis and characterization of the agents responsible. Ranavirus epizootics in amphibians are also discussed because of possible links with finfish and common anthropogenic mechanisms of spread. The source of the global epizootic of disease caused by systemic iridoviruses in finfish and amphibians is uncertain, but three possibilities are discussed: trade in food fish, trade in ornamental fish, reptiles and amphibians and emergence from unknown reservoir hosts associated with environmental change. [source] Distribution of mycobacteria in clinically healthy ornamental fish and their aquarium environmentJOURNAL OF FISH DISEASES, Issue 7 2006V Beran Abstract Some mycobacterial species (particularly Mycobacterium marinum) found in aquarium environments may cause chronic diseases in fish and cutaneous infections in humans, the so-called ,fish tank granuloma'. The presence and distribution of mycobacterial species in clinically healthy aquarium fish and their environment has not been adequately explored. The present study analysed the occurrence of mycobacteria in a decorative aquarium (Brno, South Moravia) and in five aquaria of a professional fish breeder (Bohumin, North Moravia). After Ziehl,Neelsen staining, acid-fast rods (AFR) were observed in six (14.3%) and mycobacteria were detected by culture in 18 (42.9%) of 42 tissue samples from 19 fish. Sixty-five samples of the aqueous environment from all six aquaria were examined; AFR were found in 16 (24.6%) and mycobacteria were detected by culture in 49 (75.4%) samples. Forty-one (70.7%) of 58 selected mycobacterial isolates were identified biochemically as follows: M. fortuitum, M. flavescens, M. chelonae, M. gordonae, M. terrae, M. triviale, M. diernhoferi, M. celatum, M. kansasii and M. intracellulare. The clinically important species for humans and fish, M. marinum, was not detected. Mycobacterium kansasii was isolated from one sample of the aquarium environment from North Moravia, which is a region of the Czech Republic with endemic incidence of M. kansasii in water. The incidence of other conditionally pathogenic mycobacterial species in healthy fish and in all investigated constituents of the aquarium environment including snails and crustaceans used for fish feeding, was quite high. Accordingly, mycobacterial species from aquarium environments may serve as a possible source of infection for both aquarium fish and immunodeficient fish handlers. [source] The Diplomonad Fish Parasite Spironucleus vortens Produces HydrogenTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 5 2010CORALIE O.M. MILLET ABSTRACT. The diplomonad fish parasite Spironucleus vortens causes major problems in aquaculture of ornamental fish, resulting in severe economic losses in the fish farming industry. The strain of S. vortens studied here was isolated from an angelfish and grown in Keister's modified TY-I-S33 medium. A membrane-inlet mass spectrometer was employed to monitor, in a closed system, O2, CO2, and H2. When introduced into air-saturated buffer, S. vortens rapidly consumed O2 at the average rate of 62±4 nmol/min/107 cells and CO2 was produced at 75±11 nmol/min/107 cells. Hydrogen production began under microaerophilic conditions ([O2]=33.±15 ,M) at a rate of 77±7 nmol/min/107 cells. Hydrogen production was inhibited by 62% immediately after adding 150 ,M KCN to the reaction vessel, and by 50% at 0.24 ,M CO, suggesting that an Fe-only hydrogenase is responsible for H2 production. Metronidazole (1 mM) inhibited H2 production by 50%, while CO2 production was not affected. This suggests that metronidazole may be reduced by an enzyme of the H2 pathway, thus competing for electrons with H+. [source] | ||||||||||