Melanomacrophages in three species of free-ranging sharks from the northwestern Atlantic, the blue shark Prionacae glauca (L.), the shortfin mako, Isurus oxyrhinchus Rafinesque, and the thresher, Alopias vulpinus (Bonnaterre)     

J D Borucinska  K Kotran  M Shackett  T Barker 《Journal of fish diseases》2009,32(10):883-891

The melanomacrophage aggregates or cells (MMC) are commonly used as biomarkers of exposure to pollution in fish, albeit their numbers and morphological characteristics can be influenced not only by environmental toxins but also by a range of physiological parameters and pathological conditions. Accordingly, before we can use MMC as biomarkers in any fish species, their normal, 'background' characteristics have to be established in apparently healthy fish. The knowledge of MMC in sharks is minimal. The aim of this study was to characterize MMC from 51 free-ranging, large pelagic sharks from the northwestern Atlantic, including shortfin mako, Isurus oxyrhinchus , thresher, Alopias vulpinus and blue shark, Prionacae glauca . The rationale of this study was twofold. First, because, sharks have life histories predisposing them to the accumulation of environmental toxins they constitute good sentinel species of the health of the global marine ecosystem. Second, because many shark populations are in decline or threatened by extinction, we need to expand our understanding of their health status in order to develop appropriate protective measures. All sharks were collected by sports fishing gear between June and August in 2007. Their health condition was assessed by necropsy, morphometrics, and by microscopic examination of gonads, livers, spleens and kidneys. Routine, haematoxylin and eosin and/or Pearl's reagent-stained paraffin embedded sections were studied by light microscopy. Our results provide the first data on the morphometric and morphological characteristics of MMC in viscera of apparently healthy free-ranging sharks from the northwestern Atlantic.  相似文献   

Growth and production of the Amazonian tambaqui in fixed cages under different feeding regimes     

S. Chellappa  N. T. Chellappa  W. B. Barbosa  F. A. Huntingford  M. C. M. Beveridge 《Aquaculture International》1995,3(1):11-21

Experimental culture of the native Amazonian fish tambaqui, Colossoma macropomum, in fixed cages was carried out over a period of 8 months, in Lake Urubu (Rio Grande do Norte, Brazil), to assess the viability of fixed cage culture of tambaqui and to test the influence of diet on growth rates. Nine synthetic net cages (1 m³) were each stocked with 45-day-old fish (mean weight 3 g; mean total body length 51 mm) at a density of 34 fry m^–3. During the first 2 months of culture, fish were fed a balanced formulated feed on an as-fed basis at the rate of 5% body weight day^–1. During months 3–8 this continued for fish in treatment 1 while those in treatment 2 were fed tropical regional fruits, on a wet weight basis at the rate of 5% body wt day^–1. Fish in treatment 3 were given no supplementary feed. Monthly biometric measurements were made on all fish. Fixed cage fish culture was shown to be a viable and simple technique. Survival in all treatments was 100%. With balanced supplementary feed, production was 14.4 kg m^–3, compared with 4.9 kg m^–3 and 2.1 kg m^–3, respectively, in the treatments where fish were fed with fruits and were not given any supplementary feed.  相似文献   

Aeromonas hydrophila B-haemolysin: purification and examination of its role in virulence in 0-group channel catfish, Ictalurus punctatus (Rafinesque)     

R. L. THUNE  MAUREEN C. JOHNSON  T. E. GRAHAM  R. L. AMBORSKI 《Journal of fish diseases》1986,9(1):55-61

Abstract. A single step procedure for purification of B-haemolysin from Aeromonas hydrophila is described which recovered 94% of the haemolytic activity with a sixfold increase in specific activity. Toxicity of haemolysin in 0-group channel catfish was 0–6 mg of purified protein per gram offish. Of six strains of A. hydrophila evaluated for differential toxin production and virulence in 0-group channel catfish, three B-haemolysin-deficient strains were virulent while three B-haemolysin-producing strains were avirulent.  相似文献   

Protective immunity of sevenband grouper, Epinephelus septemfasciatus Thunberg, against experimental viral nervous necrosis   总被引：9，自引：0，他引：9  

S Tanaka  K Mori  M Arimoto  T Iwamoto  & T Nakai 《Journal of fish diseases》2001,24(1):15-22

This paper describes the protective immune responses of sevenband grouper, Epinephelus septemfasciatus Thunberg, immunized with live piscine nodavirus, the causative agent of viral nervous necrosis (VNN), or the Escherichia coli – expressed recombinant coat protein. Nodavirus-neutralizing antibodies were detected at titres ranging from 1:158 to 1:1257 in serum of sevenband grouper which survived intramuscular injection with the virus, by a cell culture assay system. The virus-neutralizing ability of immune serum was also confirmed by injecting virus previously treated with serum into fish. This indicates establishment of acquired immunity in survivors and thus explains why survivors from natural infection are resistant to recurrence of the disease. Young sevenband grouper were immunized twice by intramuscular injections with the recombinant coat protein. Immunized fish produced neutralizing antibodies at high titres for at least 110 days and showed significantly lower mortalities in virus challenge tests. These results suggest the potential for vaccination against VNN in sevenband grouper, which is susceptible to piscine nodavirus at all life-stages.  相似文献   

Immune protection in carp, Cyprinus carpio L., after immunization with Aeromonas hydrophila crude lipopolysaccharide   总被引：1，自引：0，他引：1  

T. BABA  J. IMAMURA  K. IZAWA  K. IKEDA 《Journal of fish diseases》1988,11(3):237-244

Abstract. Vaccination with crude lipopolysaccharide (LPS) induced better protection against infection with Aeromonas hydrophila in carp than vaccination with formalin killed vaccine. Dipping fish in vaccine for 2 h at 25°C was more effective than intraperitoneal injection of the vaccine in procedural simplicity, lower stress loading and the degree of protection acquired. In carp immunized with crude LPS by the dip method, antibodies were not detected by bacteriai agglutination, passive haemagglutination and the agar diffusion tests. The results indicate that the protection against A. hydrophila infection in carp is not dependent on humoral immunity.  相似文献   

Ornamental lakes — an overlooked conservation resource?     

C. D. Sayer  T. A. Davidson  A. Kelly 《水产资源保护:海洋与淡水生态系统》2008,18(6):1046-1051

• 1. Shallow lakes excavated for ornamental purposes during the 18th and 19th centuries are abundant in lowland Europe. However, relative to older man‐made and/or natural lakes, these lakes may have been undervalued from the perspective of nature conservation.
• 2. To evaluate this idea a comparison was made between the aquatic macrophyte communities (submerged and floating‐leaved vegetation) of 66 shallow, English lakes including 34 ornamental lakes and 32 flooded medieval peat workings (the Norfolk and Suffolk Broads system), the latter being widely protected by conservation legislation.
• 3. Some 47%, 38% and 15% of the lakes studied were phytoplankton‐dominated, macrophyte‐dominated or deemed too shallow (<50 cm water depth), respectively, to support a macrophyte vegetation. A higher proportion of the ornamental lakes were macrophyte‐dominated (51%) by comparison with the broads (34%). In addition, many of the ornamental lakes contained diverse plant communities including abundant populations of Characeae, a common feature of lakes in the region before the major onset of eutrophication.
• 4. From the perspectives of macrophyte species richness, charophyte communities and indeed ‘reference condition macrophyte assemblages’, many of the studied ornamental lakes can be considered to be of high conservation value. Yet, in contrast to the broads, the vast majority of ornamental lakes have little conservation protection and are rarely subject to biological monitoring and/or surveying, thus leaving them vulnerable to eutrophication and inappropriate management. This study suggests that ornamental lakes are worthy of much greater attention from conservation organizations.

Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

Genetic heterogeneity of betanodaviruses in juvenile production trials of Pacific bluefin tuna, Thunnus orientalis (Temminck & Schlegel)     

T Sugaya  K Mori  T Nishioka  S Masuma  M Oka  K Mushiake  Y Okinaka  T Nakai 《Journal of fish diseases》2009,32(10):815-824

  相似文献   

Apparent digestible protein,energy and amino acid availability of three plant proteins in Florida pompano,Trachinotus carolinus L. in seawater and low‐salinity water     

M. RICHE  T.N. WILLIAMS 《Aquaculture Nutrition》2010,16(3):223-230

Two experiments were conducted with Florida pompano, Trachinotus carolinus L. at 3 and 28 g L^?1 salinity to determine apparent crude protein digestibility (ACPD), energy digestibility (AED) and amino acid availability (AAAA) from soybean meal (SBM), soy protein isolate (SPI) and corn gluten meal (CGM). Mean AAAA was similar to ACPD. In fish adapted to 3 g L^?1 salinity, they were 81.2% and 81.9% (CGM), 93.6% and 92.2% (SBM), 93.8% and 93.1% (SPI) for AAAA and ACPD respectively. In fish adapted to 28 g L^?1, they were 84.5% and 83.4% (CGM), 86.5% and 87.1% (SBM), and 83.4% and 85.0% (SPI) for AAAA and ACPD respectively. The AED was highest for SPI and lowest for SBM and inversely related to carbohydrate. The ACPD, AED and AAAA of soy products appeared to be lower in high salinity, whereas CGM was unaffected. The data suggest that SBM, SPI and CGM should be further evaluated as partial fishmeal replacements in Florida pompano diets. Application of the generated coefficients can be used to develop well‐balanced, low‐cost diets for Florida pompano reared in low salinity or seawater.  相似文献   

Putative virulence-related genes in Vibrio anguillarum identified by random genome sequencing     

Rodkhum C  Hirono I  Stork M  Di Lorenzo M  Crosa JH  Aoki T 《Journal of fish diseases》2006,29(3):157-166

The genome of Vibrio anguillarum strain H775-3 was partially determined by a random sequencing procedure. A total of 2,300 clones, 2,100 from a plasmid library and 200 from a cosmid library, were sequenced and subjected to homology search by the BLAST algorithm. The total length of the sequenced clones is 1.5 Mbp. The nucleotide sequences were classified into 17 broad functional categories. Forty putative virulence-related genes were identified, 36 of which are novel in V. anguillarum, including a repeat in toxin gene cluster, haemolysin genes, enterobactin gene, protease genes, lipopolysaccharide biosynthesis genes, capsule biosynthesis gene, flagellar genes and pilus genes.  相似文献   

Decadal trends in abundance,size and condition of Antarctic toothfish in McMurdo Sound,Antarctica, 1972–2011     

David G Ainley  Nadav Nur  Joseph T Eastman  Grant Ballard  Claire L Parkinson  Clive W Evans  Arthur L. DeVries 《Fish and Fisheries》2013,14(3):343-363

We report the analyses of a dataset spanning 39 years of near‐annual fishing for Dissostichus mawsoni in McMurdo Sound, Antarctica, 1972–2011. Data on total length, condition and catch per unit effort (CPUE) were derived from the > 5500 fish caught, the large majority of which were measured, tagged and released. Contrary to expectation, the length frequency of the McMurdo Sound catch was dominated by fish in the upper two‐thirds of the overall distribution exhibited in the industrial catch for the Ross Sea shelf. Fish length and condition increased from the early 1970s to the early 1990s and then decreased. Fish length positively correlated with Ross Sea ice extent in early spring, a relationship possibly caused by more ice encouraging larger fish to move farther south over the shelf and into the study area. Fish condition positively correlated with the amount of open water in the Ross Sea during the previous summer (Feb), perhaps reflecting greater availability of prey with the higher productivity that more open water brings. Decreasing fish size corresponds to the onset of the fishery, which targets the large individuals. CPUE was constant through 2001 and then decreased dramatically. We hypothesize that this decrease is related to the industrial fishery, which began in the 1996–97 austral summer, and concentrates effort over the ice‐free Ross Sea continental slope. As a result of limited prey choices and close coupling among mesopredators of the region, Antarctic toothfish included, the fishery appears to be dramatically altering the trophic structure of the Ross Sea.  相似文献