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1.
Yoshiko Shimahara Yun-Fen Huang Ming-An Tsai Pei-Chi Wang Shih-Chu Chen 《Fisheries Science》2010,76(3):489-494
Largemouth bass Micropterus salmoides were immunized with four different N. seriolae strains—two α-glucosidase-positive (961113, KU040801) and two α-glucosidase-negative (94260, OTTS) strains—along with Freund’s
incomplete adjuvant. After primary immunization (week 0), a booster was administered at weeks 4 and 8. Nonspecific immune
responses to multiple immunizations with the different N. seriolae strains were determined based on serum lysozyme activity and nitroblue tetrazolium (NBT)-positive cells in peripheral blood.
The serum lysozyme activity and NBT-positive cells in peripheral blood were not significantly increased even after the two
booster immunizations. Specific antibody responses against N. seriolae cells were investigated by enzyme-linked immunosorbent assay. At 4 weeks after immunization, all groups immunized with N. seriolae antigens showed significant increases in their specific antibody levels. The sera from fish immunized with different N. seriolae strains exhibited reactivity with N. seriolae sonicated antigens of 28, 30, 36 and 84 kDa by western blot analysis. After two boosters, fish were challenged with live
N. seriolae to assess the vaccine’s efficacy; however, multiple injections of the N. seriolae strains did not reduce mortality, irrespective of the bacterin. 相似文献
2.
Tamer Fawzy Ismail Atsushi Nakamura Kenji Nakanishi Takayuki Minami Takuya Murase Soetsu Yanagi Toshiaki Itami Terutoyo Yoshida 《Fisheries Science》2012,78(2):351-357
Resazurin microtiter assay (REMA) was carried out using four sulfonamides, three culture media, and four inoculum sizes as
a first screening step to establish an easy-to-interpret sulfonamides susceptibility testing method for Nocardia seriolae. The in vitro activity of sulfamonomethoxine (SMM) against 190 clinical N. seriolae isolates was then examined, and in vivo experimental treatment was performed. When the culture medium and the inoculum size
were considered in tandem, a 0.5× the original concentration of cation-adjusted Mueller–Hinton broth and an inoculum size
of 102 CFU/well showed the clearest endpoint reading for all tested drugs, and the REMA-generated data were in excellent agreement
with those generated by the reference Etest method. SMM activity showed minimum inhibitory concentration (MIC) values of 4–32 μg/ml
against all tested N. seriolae isolates. Treatment of amberjack groups experimentally infected with N. seriolae isolates having SMM MICs of 4 and 32 μg/ml, resulted in survival rates of 100% and 87.5% in the two groups, respectively.
In this study, we developed a simple visual method to test SMM activity against N. seriolae. 相似文献
3.
Tamer Fawzy Ismail Akira Takeshita Naoko Umeda Toshiaki Itami Terutoyo Yoshida 《Fisheries Science》2011,77(1):113-118
This study determined the minimum inhibitory concentrations (MICs) for oxytetracycline hydrochloride (OTC) and erythromycin
(Em), along with the α-glucosidase (α-glu) activities in 110 Nocardia
seriolae strains isolated in Miyazaki and Kagoshima prefectures in 2008–2009. The strains were examined for the presence of the tet(K), tet(L), tet(M), tet(O), tet(S), erm(A), erm(B), mph(A), mef(A), and msr(D) genes. All the α-glu-positive strains (n = 15) were OTC resistant and Em sensitive, with MICs of 32–64 and <0.125 μg/ml, respectively. All the α-glu-negative strains
(n = 95) were OTC sensitive, with MICs of 2–4 μg/ml, and most of them (93 of 95) were Em resistant, with MICs of >128 μg/ml.
The MICs for Em in the remaining 2 α-glu-negative strains were <0.125 μg/ml. The 15 OTC-resistant strains possessed the tet(K) and/or tet(L) gene(s), and all of the 93 Em-resistant strains possessed both the mef(A) and msr(D) genes. The relationship between α-glu activity and drug sensitivity of the N. seriolae strains may explain the difference in prevalence of each phenotype. Nevertheless, the relationship should be further explored
using N. seriolae isolates collected from more prefectures and farms. 相似文献
4.
Issei Nishiki Mikiko Furukawa Sho Matui Toshiaki Itami Toshihiro Nakai Terutoyo Yoshida 《Fisheries Science》2011,77(3):367-373
In Japan, Lactococcus garvieae infection has been the main fish disease in aquaculture. Although commercial oral and injectable vaccines have been used
to prevent L. garvieae infection in Japan, L. garvieae has been isolated not only from unvaccinated fish but also from vaccinated fish in which immunity induced by vaccination
had diminished. In order to obtain epidemiological information on this fish pathogen, we conducted biased sinusoidal field
gel electrophoresis (BSFGE) pattern analysis and phage typing of L. garvieae isolates (n = 427) from fish in Japan. These isolates were obtained from 13 different fish species between 1980 and 2007. In the BSFGE
analysis, L. garvieae isolates were classified into 17 groups (S1–S17) based on the SmaI digestion patterns and into four groups (A1–A4) based on the ApaI digestion patterns. Phage typing revealed five different phage susceptibility profiles (A–E) in L. garvieae isolates. Since 2005, comparisons of the results of phage typing and BSFGE have indicated the presence of a novel genotype
(S16/A4) with phage type E. All the strains belonging to this type showed lincomycin sensitivity. 相似文献
5.
Nocardia sp. is the causative agent of nocardiosis, a lethal granulomatous disease of the skin, muscle, and various inner tissues affecting various teleost and shellfish. Four species of Nocardia have been isolated from diseased fish and shellfish, namely Nocardia asteroides, Nocardia seriolae, Nocardia salmonicida and Nocardia crassostreae. Therefore, in fish aquaculture, nocardiosis has caused severe economic losses, especially in the Asian region. Considerable research has been performed, since the first report of identified Nocardia sp. in fish, to characterize Nocardia sp. and identify rapid detection techniques, immune response against infection and prophylactic approaches. In this review, the current state of knowledge about nocardiosis in fish has been presented, including the pathogenesis, diagnosis, host immune response and vaccine development. 相似文献
6.
The effects of different diets (natural or pellets) on growth, survival, and moulting interval of juvenile spider crabs, weighing
between 0.011–1.56 g and up to 17.6 mm in carapace length, were tested over a period of 90 days. During experiment I, five
diets were tested: (1) frozen shrimp—Paleomonetes sp., (2) fresh mussels—Mytilus sp., (3) white fish fillets—Merlucius merlucius, (4) blue fish fillets—Sardina pilchardus, and (5) commercial crustacean pellets. Spider crabs fed fresh mussels grew larger (0.98 ± 0.69 g) and had higher growth
rates (4.0 ± 0.7 %BWd−1) compared to the other four diets. The crabs fed shrimp pellet and frozen shrimp grew to intermediate sizes and were smaller
than the ones fed fresh mussels, but they were larger than spider crabs fed either blue or white fish fillets (0.46 ± 0.63
and 0.26 ± 0.13 g, respectively) compared to the ones fed white fish fillets (0.12 ± 0.04) and blue fish fillets (0.04 ± 0.02 g).
The spider crabs fed blue fish fillets only lasted until day 60 of the experiment, after this day none of the 20 fed this
diet were left. During experiment II, two diets were tested: (1) white and blue fish fillets and (2) commercial fish pellet.
There were no differences in growth both in weight or carapace length (2.9 ± 1.8 and 2.1 ± 1.5 g in weight, and 18.9 ± 5.0
and 17.7 ± 3.3 mm, respectively) at the end of the experiment. Similarly, there were no differences in growth rates in weight
between the two diets (1.2 ± 0.4 and 0.9 ± 0.3 %BWd−1, respectively) or in carapace length (0.4 ± 0.1 and 0.4 ± 0.2 %BWd−1, respectively). Fresh mussel appears to be a very good diet to culture the early stages of this species, while shrimp pellets
also deliver acceptable results. On the contrary, frozen shrimp, fish fillets either from blue or white species (much higher
lipid content in the blue species), and fish pellets were found to be bad diets for the culture of the early stages of M. brachydactyla. 相似文献
7.
József Lanszki Zsuzsanna S. Pallos Dénes Nagy Grace Yoxon 《Aquaculture International》2007,15(5):393-402
The diet composition and fish preference of piscivorous Eurasian otters (Lutra lutra) were studied in two fish farm systems in Hungary using spraint (otter faeces) analysis during two wintering periods. The
primary food source of otters in both fish farms was fish (97–99% of biomass). The main fish prey was small-sized, below 100 g
in weight (96% in both areas), while fish prey above 500 g comprised only 0.1–0.4% of the diet. The bulk of the otters’ diet
consisted of less-valued species, especially non-native Prussian carp (Carassius auratus gibelio). Consumption of commercial fish species ranged between 15 and 31% of the total diet. Otters preferred fish below 100 g in
weight (Ivlev’s electivity index, E
i
= 0.65–0.70), and showed a lesser preference for (or avoided) fish above 100 g in weight (E
i
= −0.37–1.00). With regard to species distribution, otters preferred small (below 100 g) grass carp (Ctenopharyngodon idella), zander (Sander lucioperca), pike (Esox lucius), Prussian carp, topmouth gudgeon (Pseudorasbora parva), while they consumed common carp (Cyprinus carpio), the most important commercial species, proportionally to its abundance in the environment (E
i
= −0.18–0.29). 相似文献
8.
Corrado Costa Stefano D’Andrea Riccardo Russo Francesca Antonucci Federico Pallottino Paolo Menesatti 《Aquaculture International》2011,19(4):765-778
European sea bass, Dicentrarchus labrax, is one of the main species cultured in Europe. In this study, non-invasive techniques such as visible-near infrared spectroscopy
and dynamometric analysis were used to discriminate concrete tank–cultured sea bass from sea cage–cultured sea bass. A total
of 198 samples were collected at six time points from 3 Italian fish farms. A partial least squares analysis was conducted
on individual animals at 48 and 96 h post-mortem to determine whether textural and spectral parameters can discriminate between concrete tank– and sea cage–reared sea bass.
The results of this analysis demonstrated that spectral measurements better discriminate individual animals at 48 h post-mortem (87% in the independent test) with respect to 96 h post-mortem (66.7% in the independent test). Differences in texture were observed between the two groups of fish, but the texture changed
in the time. The texture in sea cage–cultured fish showed higher values of measured force (N) with respect to fish reared
in concrete tanks at 48 h post-mortem. Instead, opposite results were observed at 96 h post-mortem. Fillet colour were influenced by both farm and rearing condition. 相似文献
9.
Jesús Cerezo Valverde María D. Hernández Sandra García-Garrido Carmen Rodríguez Juán Estefanell Joan I. Gairín Carlos J. Rodríguez Ana Tomás Benjamín García García 《Aquaculture International》2012,20(1):71-89
In this study, HPTLC was used to make a quantitative analysis of the total lipid content (TL dry weight) and their classes
in 39 samples, including molluscs, crustaceans, fish and meals in an attempt to identify those most suitable for formulating
diets for cephalopods by reference to an index of nutritional quality (OILC: Oser’s index modified for lipid classes). All the crustaceans analysed (<10% TL), fish from artisanal fisheries such as
Boops boops, Gadus poutassou, Mugil sp. and Gadus minutus (<10% TL) and the plant meals (TL < 5%) would cause fewer digestive problems than the fish that were a by-catch from fish
farms (B. boops or Sparus aurata), pelagic species (Sardina pilchardus or Trachurus trachurus) or krill meal, which are characterised by their high lipid content (20–60% TL). These latter feeds were associated with
neutral lipids, mainly triglycerides during the summer. Mytilus galloprovincialis, Carcinus maenas, G. poutassou, Mugil sp., S. pilchardus and G. minutus had a more appropriate lipid content and profile during the winter, when they showed a higher OILC due to the greater variety of polar lipid classes they contained. Phospholipids like PS, PI and PE seem to be limiting nutrients
in cephalopods because of their high content (78–542, 41–309 and 152–2,114 mg/100 g, respectively) compared with the rest
of the samples. None of the meals analysed showed a good nutritional balance per se and should only be used in conjunction
with other foods. 相似文献
10.
Thomas H. Galley Frederico M. Batista Richard Braithwaite Jon King Andy R. Beaumont 《Aquaculture International》2010,18(3):315-325
The blue mussel Mytilus
edulis is a commercially important species whose fishery and culture generally relies on natural spat collection. Hatchery-production
could provide an alternative source of seed, enabling reliable expansion of the industry. Mussel spawning and larval rearing
trials were carried out to optimise elements of hatchery production. Culturing fertilised eggs at low density (20–200 eggs cm−2) rather than high density (400–720 eggs cm−2) significantly improved the quality of first veliger larvae and differences in this improvement were evident between the
eggs from different females (maternal effects). Veliger larval growth at 17 or 21°C was significantly faster than growth at
14°C. Feeding veliger larvae an identical total ration either daily or at 2–3 day intervals did not significantly affect their
growth. Different microalgal diets (1: Isochrysis sp. (clone T-ISO), 2: Chaetoceros
calcitrans forma pumilus, 3: C. muelleri, 4: mixed Isochrysis sp. (clone T-ISO) and C. calcitrans f. pumilus, and 5: mixed Isochrysis sp. (clone T-ISO) and C. muelleri) were tested on veliger larval growth and mixed diets outperformed single-species diets. 相似文献
11.
Wenji Wang Jianlin Chen Baoshan Liao Liqun Xia Suying Hou Zhiwen Wang Yishan Lu 《Journal of fish diseases》2019,42(5):657-666
Nocardia seriolae, a facultative intracellular bacterium, is the main pathogen of fish nocardiosis. Bioinformatic analysis showed that the histone‐like DNA‐binding protein (HLP) gene of N. seriolae (nshlp) encoded a secreted protein and might target the mitochondria in the host cell. To further study the preliminary function of HLP in N. seriolae (NsHLP), the gene cloning, extracellular products identification, subcellular localization, overexpression and apoptosis detection assay were carried out in this study. Mass spectrometry analysis of the extracellular products from N. seriolae showed that NsHLP was a secreted protein. Subcellular localization of HLP‐GFP fusion proteins mainly assembled in the nucleus, which indicated that the NsHLP was co‐located with the nucleus rather than mitochondria in fathead minnow (FHM) cells. Notably, the expression of NsHLP had changed the distribution of mitochondria into lumps in the FHM cell. In addition, apoptotic features were found in the transfected FHM cells by overexpression of NsHLP. Quantitative assays of mitochondrial membrane potential value, caspase‐3 activity and pro‐apoptotic genes mRNA (Bad, Bid and Bax) expression level demonstrated that the cell apoptosis was induced in the transfected FHM cells. All the results presented in this study provided insight on the function of NsHLP, which suggested that it may participate in the cell apoptosis regulation and play an important role in the pathogenesis of N. seriolae. 相似文献
12.
Zhongming Zheng Chunhua Jin Mingyun Li Peifeng Bai Shuanglin Dong 《Aquaculture International》2008,16(6):581-589
The metabolic responses of the juvenile Miichthys miiuy in terms of oxygen consumption and ammonia excretion to changes in temperature (6–25°C) and salinity (16–31 ppt) were investigated.
At a constant salinity of 26 ppt, the oxygen consumption rate (OCR) of the fish increased with an increase in temperature
and ranged between 133.38 and 594.96 μg O2 h−1 g−1 DW. The effect of temperature on OCR was significant (P < 0.01). Q10 coefficients were 6.80, 1.41, 1.29 and 2.36 at temperatures of 6–10, 10–15, 15–20 and 20–25°C, respectively, suggesting that
the juveniles of M. miiuy will be well adapted to the field temperature in the summer, but not in the winter. The ammonium excretion rates (AER) of
the fish were also affected significantly by temperature (P < 0.01). The O:N ratio at temperatures of 6, 10, 15 and 20°C ranged from 13.12 to 20.91, which was indicative of a protein-dominated
metabolism, whereas the O:N at a temperature of 25°C was 51.37, suggesting that protein-lipids were used as an energy substrate.
At a constant temperature of 15°C, the OCRs of the fish ranged between 334.14 (at 31 ppt) and 409.68 (at 16 ppt) μg O2 h−1 g−1 DW. No significant differences were observed in the OCR and AER of the juveniles between salinities of 26 and 31 ppt (P > 0.05). The OCR and AER at 16 ppt were, however, significantly higher than those at 26 and 31 ppt (P < 0.05), indicating salinity lower than 16 ppt is presumably stressful to M. miiuy juveniles. 相似文献
13.
Tetsushi Kageyama Tetsuya Yanagida Kenichi Ohara Hiroshi Yokoyama 《Fisheries Science》2009,75(3):657-663
Two types of infection with myxosporean parasites, which were different in cyst size, were found from the gill of Rhinogobius sp. OR collected from the Nagara River, Gifu Prefecture, Japan. A myxosporean forming large-type cysts in the gill filament
was morphologically identified as Henneguya rhinogobii. Another myxosporean forming small-type cysts was found to be parasitic in the gill lamella. Average spore sizes of the latter
myxosporean were 15.8 (range 14.2–17.8) μm in length, 5.3 (4.7–5.8) μm in width, 6.5 (5.9–7.6) μm in polar capsule length
and 34.9 (25.3–42.9) μm in caudal appendage length, which were almost identical to those of H. rhinogobii. However, the two were distinguishable by the location in the gill (intrafilamental or intralamellar) and by the difference
in the sequence of SSU rDNA (about 96% similarity). We propose the myxosporean forming intralamellar small-type cysts as Henneguya pseudorhinogobii n. sp. and redescribe H. rhinogobii by morphological and molecular studies. 相似文献
14.
Tomokazu Itano Hidemasa Kawakami Masahiro Sakai 《Aquaculture (Amsterdam, Netherlands)》2006,261(4):1175-1180
In an attempt to develop a vaccine against Nocardia seriolae, related species of live bacteria N. soli, N. fluminea, and N. uniformis were injected into yellowtail Seriola quinqueradiata. In addition, fish were challenged with a low virulence strain of N. seriolae to model the concept of use of a live vaccine. The fish injected with live N. soli and N. fluminea cells showed slight resistance against an artificial challenge with N. seriolae. On the other hand, the fish that survived the N. seriolae infection showed complete resistance to the N. seriolae challenge. These results suggest that protective immune responses against N. seriolae are induced in yellowtails. 相似文献
15.
Gary Fry David A. Milton Tonya Van Der Velde Ilona Stobutzki Retno Andamari Badrudin Bambang Sumiono 《Fisheries Science》2009,75(1):145-158
Red snappers were examined for reproductive biology and age-0 habitat preferences. Spawning in red snappers occurred throughout
the year in northern Australia and eastern Indonesia; at least 10–30% of females and 40–80% of males were in ripe or spawning
condition in most months. Northern Australian populations showed a spawning peak from July to December (L. erythropterus) and September to March (L. malabaricus). Eastern Indonesian L. malabaricus had a less defined pattern with two peaks: January–March and October. Size at first maturity was 240 mm for males and 250–300 mm
for females. L
50 estimates were similar between species in northern Australia: 270–280 mm (males) and 350–370 mm (females). Maximum batch
fecundity was 676,100 oocytes for L. erythropterus and 997,000 oocytes for L. malabaricus. Higher mean abundances of age-0 L. erythropterus were found in silty and coarse sand/rubble estuarine habitats of northern Australia (456 ± 119 fish/km2) compared with sandy coastal habitats (5 ± 3 fish/km2). Most age-0 snapper caught at Sape (eastern Indonesia) were L. malabaricus (91%) with mean abundances of 312 ± 14 fish/km2. The similarities in the reproductive characteristics of red snappers suggest that successful management approaches adopted
in northern Australia should be considered in eastern Indonesia. 相似文献
16.
Tohya Yasuda Kazuyoshi Komeyama Keitaro Kato Yasushi Mitsunaga 《Fisheries Science》2012,78(2):229-235
We investigated the usefulness of acceleration loggers in aquaculture by examining net-cage use and metabolic rates in red
sea bream, Pagrus major. First, the fish’s metabolic rate (mg O2 kg−1 min−1) was measured with the logger in a swim tunnel at designated water velocities. We found that metabolic rate could be expressed
by using a linear regression model of the activity rate index (unitless min−1) derived from acceleration data. Using this equation, the field metabolic rates of three fish in a net cage were monitored
and were estimated at 14.1–15.0 kcal kg−1 day−1. The results suggested that 15–19% of energy from satiation feeding ration was consumed for metabolism and activity in the
net cage. The loggers showed orderly net-cage use by the fish. Tagged individuals used the whole cage from surface to bottom,
but individual fish that preferred the surface area rarely used the bottom, and vice versa. Metabolic rate increased significantly
with distance of the fish from their preferred depths. The logger provided information on the physiological and behavioral
responses of fish in a given breeding system, and its use should contribute to the design of practical aquaculture systems. 相似文献
17.
18.
Mohsen Abdel-Tawwab 《Aquaculture International》2012,20(2):317-331
Yeasts used as a probiotic in fish diets could stimulate fish resistance against bacterial infection and could enhance the
activities of digestive enzymes in fish guts. In addition to yeast importance, dietary protein is another important part in
fish diets that should be carefully optimized to meet fish requirement. It is proposed that the yeast supplementation may
enhance the dietary protein turnover and reduce the protein requirement for fish. Therefore, the interactive effects of dietary
protein and yeast levels on the growth performance of Nile tilapia, Oreochromis niloticus (L.) fry and their challenge against Aeromonas hydrophila infection was evaluated. In the present study, ten experimental diets were formulated to contain either 35% or 45% crude
protein (CP). For each protein level treatment, bakery yeast (Saccharomyces cerevisiae) was supplemented at 0.0, 0.50, 1.0, 2.0, or 5.0 g/kg diet. Fish (0.25–0.48 g) were distributed at a rate of 25 fish per
140-L aquarium. For each diet, triplicate aquaria were fed twice a day, 5 days a week for 12 weeks. Fish growth and feed utilization
were significantly affected by either dietary protein or yeast levels alone, while no significant effect of their interaction
was observed. The highest fish growth was obtained at 1.0–5.0 g yeast/kg diet at both protein levels; however, the fish performance
at 45% CP was better than that fed on 35% CP diets. The optimum feed conversion ratio (FCR) was obtained when fish fed on
1.0–5.0 and 2.0–5.0 g yeast/kg diet at 35 and 45% CP, respectively. The cumulative fish mortality, after interperitoneal injection
with A. hydrophila for 10 days, and bactericidal activity was significantly higher in fish fed 35% CP diets than those fed 45% CP diets. Both
variables decreased significantly with the increase in yeast levels. The lowest bacterial count and bactericidal activity
were obtained in fish fed 5.0 g yeast/kg diet irrespective to dietary protein levels. It could be concluded that the inclusion
of live bakery yeast in practical diets could improve the growth performances, feed utilization, and physiological status
of Nile tilapia fry and their challenge against A. hydrophila infection. Moreover, fish performance when fed 45% CP diet was better than those fed 35% CP diet. Based on these results,
the most suitable yeast level for maximum Nile tilapia growth was determined to be 2.0 g yeast/kg diet with 45% CP diet; however,
this level was recommended to stimulate their productive performance and enhances their resistance against A. hydrophila infection. 相似文献
19.
Characterization of spaC‐type Erysipelothrix sp. isolates causing systemic disease in ornamental fish
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E K Pomaranski S R Reichley R Yanong J Shelley D B Pouder J C Wolf K V Kenelty B Van Bonn F Oliaro B Byrne K A Clothier M J Griffin A C Camus E Soto 《Journal of fish diseases》2018,41(1):49-60
Since 2012, low‐to‐moderate mortality associated with an Erysipelothrix sp. bacterium has been reported in ornamental fish. Histological findings have included facial cellulitis, necrotizing dermatitis and myositis, and disseminated coelomitis with abundant intralesional Gram‐positive bacterial colonies. Sixteen Erysipelothrix sp. isolates identified phenotypically as E. rhusiopathiae were recovered from diseased cyprinid and characid fish. Similar clinical and histological changes were also observed in zebrafish, Danio rerio, challenged by intracoelomic injection. The Erysipelothrix sp. isolates from ornamental fish were compared phenotypically and genetically to E. rhusiopathiae and E. tonsillarum isolates recovered from aquatic and terrestrial animals from multiple facilities. Results demonstrated that isolates from diseased fish were largely clonal and divergent from E. rhusiopathiae and E. tonsillarum isolates from normal fish skin, marine mammals and terrestrial animals. All ornamental fish isolates were PCR positive for spaC, with marked genetic divergence (<92% similarity at gyrB, <60% similarity by rep‐PCR) between the ornamental fish isolates and other Erysipelothrix spp. isolates. This study supports previous work citing the genetic variability of Erysipelothrix spp. spa types and suggests isolates from diseased ornamental fish may represent a genetically distinct species. 相似文献