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1.
Development and detection of phosphorus deficiency in Atlantic salmon, Salmo salar L., parr and post-smolts 总被引：4，自引：0，他引：4
A pathological condition was induced in Atlantic salmon, Salmo salar L., by feeding a diet severely deficient in phosphorus. Parallel results were obtained in two consecutive experiments, one in fresh water and one in sea water. The deficiency condition was first manifest as a reduction in whole-body calcium (Ca) and phosphorus (P) levels and the development of abnormally soft and malformed bones. In later stages, growth was severely impaired and there was elevated mortality compared with fish fed a diet with sufficient phosphorus.
Two semipurified casein-based test diets were used in the experiments. The low-P diet contained only the P from casein, 3.5 g kg−1 or 0.35%, whereas the reference diet was supplemented with P and contained 9.0 g kg−1 or 0.9%, The diets were fed to salmon parr in fresh water (initial weight 4.7 g) and to post-smolts in sea water (initial weight 113 g) for 12 and 15 weeks, respectively. In both experiments, the fish grew adequately for a prolonged period, whereas the whole-body Ca and P levels declined almost immediately. Within a few weeks, the whole-body P content was reduced to ≊ 65% of the initial value, and Ca to 40%. The reductions in mineral content were most severe in the mineral-rich tissues, bones and scales. On gross examination, all bony structures were abnormally soft. The ribs were wrinkly, and the spine displayed scoliotic changes. These changes were correlated to the reduction in bone mineralization, and were manifest at the time when reductions in growth rate could be noted.
After the deficient fish were fed adequate levels of P for 9 weeks, their whole-body mineral levels returned to normal. The bone lesions did not heal completely during the same period of time. 相似文献
Two semipurified casein-based test diets were used in the experiments. The low-P diet contained only the P from casein, 3.5 g kg
After the deficient fish were fed adequate levels of P for 9 weeks, their whole-body mineral levels returned to normal. The bone lesions did not heal completely during the same period of time. 相似文献
2.
Deformities of skeletal structures, the heart, and other organs are a recurrent problem in species used in intensive aquaculture.
Elevated egg incubation temperature appears to be a high risk factor in the development of these malformations, but the causal
relation has not been established. Our aim was to identify candidate genes involved in the development of heat induced deformities
in Atlantic salmon (Salmo salar). Temperature sensitive genes were isolated by RNA Arbitrarily Primed (RAP)-PCR. A total of 33 RAP-PCR products were successfully
sequenced, and the expression of eight identified genes was further examined by RT-PCR from pooled samples of heat exposed
embryos. Five of these genes were demonstrated to be temperature sensitive, of which four were shown to be up-regulated and
one was down-regulated at elevated water temperatures. The atrial natriuretic peptide (ANP) gene, which is a promising candidate for heart deformities, showed the highest level of heat induction. Three additional
RAP-PCR products identified as heterogeneous nuclear ribonucleprotein (hnRNP) A0, acyl CoA binding protein (ACBP) and mitochondrial (mt)-HSP70 showed up-regulated mRNA expression in response to elevated water temperature. The single down-regulated gene was identified
as an Atlantic salmon (Salmo salar) homolog of the cysteine and tyrosine-rich 1 (CYYR1) gene. This study demonstrated that a temperature elevation of only 4 °C during the early stages of the organogenesis in
Atlantic salmon induce altered expression of a number of genes, which are candidates for the development of heat induced deformities. 相似文献
3.
The development of a pathological condition in the distal intestine of Atlantic salmon, Salmo salar L., induced by dietary soybean meal, was studied in a 6-week feeding experiment. The fully developed condition, as observed after 3 weeks on the experimental diets, was characterized by: (1) a shortening of heights of the mucosal foldings; (2) a loss of the normal supranuclear vacuolization of the absorptive cells in the intestinal epithelium; (3) a widening of the central stroma within the mucosal foldings, with increased amounts of connective tissue; and (4) a profound infiltration of inflammatory cells in the lamina propria. The first signs of morphological changes were observed after 2 days on a diet containing a solvent extracted soybean meal, and within 7 days, all the above mentioned signs were observed. When the fish were subsequently transferred to a control diet, the mucosal folds were rebuilt from the base, resulting in an apparently functional epithelium after 3 weeks. Starved fish also exhibited characteristic changes of the mucosa, including a finely granular cytoplasm replacing the supranuclear vacuoles seen in the epithelial cells of normal fish. In addition, a pattern of irregularly spaced indentations developed in the epithelium of the simple folds. The condition induced by dietary soybean meal was classified as a no n-infectious subacute enteritis, and a pathogenesis involving immunological mechanisms is suggested. 相似文献
4.
A M Bakke‐McKellep C McL Press G Baeverfjord
Krogdahl T Landsverk 《Journal of fish diseases》2000,23(2):115-127
Extracted soybean meal (SBM) in the diet for Atlantic salmon, Salmo salar L., causes an inflammatory response in the distal intestine. The morphological changes of the epithelial cells and a characterization of the inflammatory cell infiltrate of the distal intestinal mucosa were studied using a panel of enzyme and immunohistochemical markers. The salmon (average body weight 927 g) used in the study were fed either a fishmeal‐based diet (control diet) or a diet in which 30% of the fishmeal protein was replaced with SBM protein (SBM diet). In salmon fed SBM, there were markedly reduced enzyme reactivities in the distal intestinal epithelial cells, both in the brush border [5′‐nucleotidase (5′N), Mg2+‐ATPase, alkaline phosphatase (ALP) and leucine aminopeptidase (LAP)] and in the intracellular structures [alkaline and acid phosphatase, non‐specific esterase (NSE) and alanine aminopeptidase (AAP)]. There appeared to be an increased presence of cells of monocytic lineage, including macrophages, as well as neutrophilic granulocytes and immunoglobulin (Ig) M in the lamina propria of the SBM‐fed fish. The mid intestine showed little response to the diet. The results suggest that toxic/antigenic component(s) of SBM affect the differentiation of the distal intestinal epithelial cells and may help explain the reduced nutrient digestibilities previously reported in salmonids fed extracted SBM. 相似文献
5.
A controlled experiment mimicking Atlantic salmon (Salmo salar) pre-smolt farming conditions showed that fish exposed to 150 and 175% super oxygenated water produced higher levels of
carbon dioxide with the subsequent decrease in water pH compared to control fish exposed to 100% O2. At the 7th day of exposure the hyperoxic fish showed larger individual variation in swimming activity compared to the controls.
The individual variance in activity, tail beat frequency and scattering in the tanks among super oxygenated fish decreased
from the 7th to the 21st day of exposure. The behavioural effects of hyperoxia were seen in relation to altered feed consumption
halfway through the experiment, lower body weight, and altered haematological variables at day 21 of exposure. Plasma chloride
was reduced in the exposed fish and haemoglobin decreased with increasing oxygen saturations. Plasma cortisol was elevated
only in the 150% oxygenated group at day 21, while no effect on osmolality was recorded. The alterations in physiology and
behaviour from day 7 to day 21 may be explained in terms of acclimation to increased oxygen saturations. This study shows
that behaviour may be used as an indication of impaired water quality that may influence animal welfare negatively and eventually
prevent an efficient production. 相似文献
6.
Grete Baeverfjord Ståle Refstie Per Krogedal 《Aquaculture (Amsterdam, Netherlands)》2006,261(4):1335-1345
Regurgitation (belching) of oil is a problem in sea farmed rainbow trout kept in water with fluctuating salinity. This often coincides with abdominal distension syndrome, which is associated with osmoregulatory stress and lipid indigestion. The present study investigated combined effects of water stability in extruded feeds and fluctuating water salinity on feed consumption, growth, nutrient digestibility, gastrointestinal transit, and accumulation of water and oil in the stomach of rainbow trout. Diets were produced with high or low water stability, which were characterised by a novel water stability test. In an initial 84 days growth experiment, each diet was fed to six groups of 772 g trout, of which three tanks were supplied with full-strength seawater, and three tanks were fluctuated between seawater and freshwater (7 h per day during 3 successive days per week). No significant effects were seen, although the feed intake appeared slightly lowered by low dietary water stability at fluctuating salinity. In a second experiment, each diet was fed to four groups of 1 kg trout, of which two tanks were supplied with full-strength seawater, and two tanks were fluctuated between seawater and brackish water (17‰ 7 h per day daily). Low water stability of the diet resulted in accumulation of oil in the stomach, and this response was worsened when the salinity of the rearing water fluctuated. It also corresponded with reduced lipid digestibility. Consequently, low water stability of the diet caused an oil separation in the stomach that may result in oil-belching in rainbow trout suffering from osmoregulatory stress. 相似文献
7.
Pedersen ME Takle H Ytteborg E Veiseth-Kent E Enersen G Færgestad E Baeverfjord G Hannesson KO 《Fish physiology and biochemistry》2011,37(4):821-831
We have previously characterized the development of vertebral fusions induced by elevated water temperature in Atlantic salmon.
Molecular markers of bone and cartilage development together with histology were used to understand the complex pathology
and mechanism in the development of this spinal malformation. In this study, we wanted to use proteomics, a non-hypothetical
approach to screen for possible new markers involved in the fusion process. Proteins extracted from non-deformed and fused
vertebrae of Atlantic salmon were therefore compared by two-dimensional electrophoresis (2DE) and MALDI-TOF analysis. Data
analysis of protein spots in the 2DE gels demonstrated matrilin-1, also named cartilage matrix protein, to be the most highly
up-regulated protein in fused compared with non-deformed vertebrae. Furthermore, real-time PCR analysis showed strong up-regulation
of matrilin-1 mRNA in fused vertebrae. Immunohistochemistry demonstrated induced matrilin-1 expression in trans-differentiating
cells undergoing a metaplastic shift toward chondrocytes in fusing vertebrae, whereas abundant expression was demonstrated
in cartilaginous tissue and chordocytes of both non-deformed and fused vertebrae. These results identifies matrilin-1 as a
new interesting candidate in the fusion process, and ratify the use of proteomic as a valuable technique to screen for markers
involved in vertebral pathogenesis. 相似文献
8.
Xavier A. Gutirrez Jelena Kolarevic Harald Takle Grete Baeverfjord Elisabeth Ytteborg Bendik Fyhn Terjesen 《Aquaculture Research》2019,50(9):2687-2697
The present study examined the protective effects of water chloride (Cl?) towards nitrite toxicity in Atlantic salmon parr during 84‐day long nitrite exposure. Effects on growth, histology, blood indices and gene expression were studied at a fixed nominal Cl? concentration of 200 mg/L and at several water nitrite concentrations (0, 0.5, 2, 5 and 10 mg/L NO2?–N). The specific growth rate was significantly reduced during the first three weeks at a Cl:NO2?–N ratio of 21:1, suggesting the activation of coping mechanisms at the later stages of the experiment. No significant effect of nitrite on gill histology and mortality was found. Nitrite accumulated in plasma; however, a Cl:NO2?–N ratio of 104:1 or higher prevented nitrite entry. The concentration of NO2?–N in plasma was significantly reduced at the end of the study, supporting the hypothesis of coping mechanisms. Cystic fibrosis transmembrane conductance regulator (cftr)‐1 showed a significant up‐regulation at highest nitrite concentration on day 22, and in three of the highest exposure groups at the end of the experiment. Our findings suggest that a Cl:NO2?–N ratio above 104:1 should be maintained through episodes of nitrite accumulation in water during the production of Atlantic salmon parr. 相似文献
9.
Gerd Marit Berge P. Eckhard Witten Grete Baeverfjord Anne Vegusdal Simon Wadsworth Bente Ruyter 《Aquaculture (Amsterdam, Netherlands)》2009,296(3-4):299-308
Vegetable oils, typically high in n − 6 fatty acids, are necessary alternatives in fish feed production. Such oils have been tested in salmonid diets with good growth results, but with major changes in lipid composition. The aim of this study was to provide information regarding the effect of the higher dietary n − 6/n − 3 fatty acid ratio caused by vegetable oil on growth, chemical composition and bone development, on eicosanoid production and on formation and mineralization of bone.A feeding experiment was carried out in juvenile Atlantic salmon (Salmo salar). Groups of fish (1.28 g) were fed diets added fish oil (FO) or soybean oil (SO) as the main lipid source through the 174 days long experimental period with sampling points at days 0, 31, 53, 96, 136 and 174 up to smoltification. Subsequently, fish performance was observed after 2, 8 and 18 months in sea water.Weight was significantly higher in the fish oil group (95.4 g) than in the soybean oil group (87.4 g) after the 174 days experimental period. This difference developed during short day treatment prior to smoltification, and the fish oil group had a significantly higher growth rate (TGC) during this period (1.62 vs 1.45). Whole body mineral analysis displayed low levels of Ca (2400 and 3500 mg kg−1) and P (3200 and 3900 mg kg−1) in all samples. The corresponding Ca:P ratio ranged from 0.74 to 0.91. On day 136 the level of Ca, and Ca/P ratio, were significantly higher in the fish oil group than in the soybean oil group. There was a significant increase in n − 6 fatty acids and decrease in n − 3 fatty acids in the soybean oil group compared to the fish oil group for both TAG and PL in vertebrae. Individual variation was large in plasma prostaglandin E2 (PGE2), and at day 174 the trend was towards a higher level in the soybean oil group. Radiography analyses demonstrated a distinctive pattern of development of spinal pathology with time and fish size, similar in both groups. Hyper dense vertebrae dominated at earlier stages, fusion-type malformations dominated at harvest size. The histological examination of the vertebrae revealed no differences between treatments.The results suggest that vegetable oil as a replacement for fish oil influence the arachidonic acid level in phospholipids of vertebrae, may slightly increase production of PGE2 in blood, and reduce vertebrae mineralization around the sensitive smoltification phase. These trends did not lead to any detectable skeletal malformations. Differences in growth and vertebrae mineralization observed around smoltification disappeared during the seawater phase. 相似文献
10.
Two trials were initiated to investigate the consequences of including various soybean products in diets for Atlantic salmon Salmo salar L. on (1) mortality following infection by Aeromonas salmonicida ssp. salmonicida during a cohabitation challenge, and (2) the lysozyme and IgM content of the intestinal mucosa. Groups of salmon were fed control diets containing fishmeal as the sole protein source (Contr1 and Contr2, respectively), soy concentrate-containing diets (SoyConc1 and SoyConc2, respectively), or diets containing either solvent-extracted soybean meal (SoyMeal, trial 1) or soybean molasses (SoyMol, trial 2), an alcohol extract of soybean meal. Both SoyMeal and SoyMol caused enteritis-like changes in the distal intestine, which were not observed in fish fed the Contr1, Contr2, SoyConc1, or SoyConc2 diets. There were significant differences ( P < 0.05) in mortality between feeding groups following the A.s. salmonicida challenge: these differences were greatest in fish fed SoyMeal (65.6%), least in fish fed SoyConc1 (60.5%), and intermediate in the fish fed the Contr1 diet (62.9%). The SoyMol diet caused significantly ( P < 0.0001) increased levels of both lysozyme and IgM in the mid and distal intestinal mucosa. It is concluded that components of soybean meal and soybean molasses cause an inflammatory response in the distal intestine that may lead to increased susceptibility to furunculosis. 相似文献