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101.
Saponins and phytosterols in diets for European sea bass (Dicentrarchus labrax) juveniles: effects on growth,intestinal morphology and physiology
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A. Couto T.M. Kortner M. Penn G. Østby A.M. Bakke Å. Krogdahl A. Oliva‐Teles 《Aquaculture Nutrition》2015,21(2):180-193
This study aimed to elucidate the effects of two soy antinutrients, saponins and phytosterols, on growth, intestinal health and function of European sea bass juveniles. Seven fishmeal‐based diets were formulated: a control diet without antinutrients and six experimental diets containing low or high levels of soyasaponins (SapL and SapH, respectively), low or high levels of phytosterols (PhytL and PhytH, respectively) and low or high levels of soyasaponins + phytosterols (SapPhytL and SapPhytH, respectively). A feeding trial was conducted for 59 days after which blood was collected for plasmatic cholesterol quantification and intestinal samples were collected for histology, digestive enzymes activity and gene expression analysis. Histology was also performed at day 15. PhytL resulted in high distal intestine (DI) relative weight and decreased plasma cholesterol, while PhytH caused inflammatory changes in the DI. SapH depressed maltase and alkaline phosphatase activity in DI and the histological evaluation indicated some inflammatory changes. The SapPhytH resulted in decreased maltase activity in the DI and indications of inflammatory changes that were supported by the results on gene expression profiles. The antinutrients tested did not compromise growth, however, caused some gastrointestinal disturbance that may affect fish in the long term. 相似文献
102.
Geir I. Vestøl Carolin Fischer Olav Høibø Audun Øvrum 《Scandinavian Journal of Forest Research》2016,31(8):758-765
This study provides an analysis on the variability of structural timber of Norway spruce (Picea abies) grown in Norway. Density, modulus of elasticity (MOE) and bending strength were measured on 1188 boards from 205 trees, sampled from 14 sites throughout Southern Norway, Eastern Norway and Trøndelag. The area represents the procurement area for the majority of Norwegian sawmills. The variability of the timber properties was analysed in a linear mixed model where the random variance was divided into variance due to site, variance due to trees and within-tree variance. Models describing variance due to site based on site index, altitude and latitude were developed, and combined with data from the Norwegian National Forest Inventory to estimate mean values and variability of the timber properties. The results showed that major parts of the variance due to site are explained by altitude and site index, and for density also by latitude. Major parts of the variance due to site and the variance due to trees in bending strength and MOE were explained by density. 相似文献
103.
Espen Lund Øyvind A. Garmo Heleen A. de Wit Torstein Kristensen Kate L. Hawley Richard F. Wright 《Water, air, and soil pollution》2018,229(11):368
Acid deposition has led to acidification and loss of fish populations in thousands of lakes and streams in Norway. Since the peak in the late 1970s, acid deposition has been greatly reduced and acidified surface waters have shown chemical recovery. Biological recovery, in particular fish populations, however, has lagged behind. Long-term monitoring of water chemistry and fish populations in Lake Langtjern, south-eastern Norway, shows that around 2008, chemical recovery had progressed to the point at which natural reproduction of brown trout (Salmo trutta) reoccurred. The stocked brown trout reproduced in the period 2008–2014, probably for the first time since the 1960s, but reproduction and/or early life stage survival was very low. The results indicate that chemical thresholds for reproduction in this lake are approximately pH?=?5.1, Ali?=?26 μg l?1, ANC?=?47 μeq l?1, and ANCoaa?=?10 μeq l?1 as annual mean values. These thresholds agree largely with the few other cases of documented recovery of brown trout in sites in Norway, Sweden, and the UK. Occurrence and duration of acidic episodes have decreased considerably since the 1980s but still occur and probably limit reproduction success. 相似文献
104.
Utilization of H2SO4‐hydrolysed phosphorus from herring bone by‐products in feed for Atlantic salmon (Salmo salar) 0+ postsmolt
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S. Albrektsen E.‐J. Lock G. Bæverfjord M. Pedersen A. Krasnov H. Takle E. Veiseth‐Kent R. Ørnsrud R. Waagbø E. Ytteborg 《Aquaculture Nutrition》2018,24(1):348-365
The utilization efficiency of phosphorus (P) hydrolysed from herring by‐products in feed for Atlantic salmon 0+ postsmolt was studied. Seven diets were produced with a low P level (D1): 5 g soluble P/kg, with P hydrolysed from herring by‐products (D2, D3, D4): 7, 9 and 11 g soluble P/kg, or blue whiting fish bone meal (D5): 9 g soluble P/kg, and with P from NaH2PO4 (D6, D7): 9 g soluble P/kg diet. Diet D7 was also added (NH4)2SO4. Fish fed D1 had significantly lower growth compared to D3, D5 and D7, morphological changes in bone consistent with low mineral contents, significantly reduced scale macromineral contents and changes in P markers, that is bone ALP and NaPi in pyloric caeca. The average P retention was 3.6 and 3.2 g P/kg weight gain, respectively, in D2–D7 and in D1. Fish fed D3, D5 and D6 showed similar growth, P digestibility, tissue mineralization, P retention and P excretion. The dietary P requirement in salmon was met between 5.1 and 7.4 g/kg soluble P (DM). This study shows that P hydrolysed from fish bones can be recycled and used as an efficient P source in feed for Atlantic salmon. 相似文献
105.
E. M. Kolstoe T. Iversen Ø. Østensvik A. Abdelghani I. Secic T. Nesbakken 《Zoonoses and public health》2015,62(2):125-130
As Specific Pathogen‐Free (SPF) pig herds are designed and managed to prevent specific pig diseases, it might be feasible to expand the list of micro‐organisms also including zoonotic pathogens such as Campylobacter coli as this agent has its origin in pigs. In a previous survey, 15 of 16 of SPF herds were found free from human pathogenic Yersinia enterocolitica. Accordingly, three nucleus and seven multiplying herds were surveyed for Campylobacter to investigate whether the Norwegian SPF pig pyramid also might be free from this agent. In conclusion, the intervention of Campylobacter at the herd level might be possible as four of 10 SPF herds tested negative in two sets of samples from both autumn 2008 and summer/early autumn 2010. The four negative herds were all located in remote areas several kilometres away from conventional pig farming while the positive SPF farms were all situated in neighbourhoods with conventional pig production. It seems more difficult to control Campylobacter than some specific animal disease agents and another significant zoonotic agent, Y. enterocolitica, in pig herds. 相似文献
106.
Arne Sæbø Inger Sundheim Fløistad Jan Netland Brynjar Skúlason Øyvind Meland Edvardsen 《New Forests》2009,38(2):143-156
Abies nordmanniana and Abies lasiocarpa, established for Christmas tree production in southwestern Norway (58°44′N, 5°38′E), were treated with different weed control
methods, including chemicals, use of black plastic mulch, grass or clover as ground cover, living mulch and mechanical hoeing.
Ground cover with black plastic mulching resulted in the best growth and quality in A. lasiocarpa; the least favourable treatment was when grasses were allowed to grow close to the trees. Unless measures were taken to remove
this competing vegetation, the ground cover grew over the trees, smothering 94% of them. A. nordmanniana plants grew to the same height on plots with no weed control as on plots with thorough weed eradication. Stem diameter decreased
on plots with ground vegetation compared to seedlings grown in the weed-free environment. The use of Trifolium repens as ground cover decreased height growth by 30% compared to thorough weed control. Both grasses and clover sown as living
mulch, damaged the trees more than did natural weed vegetation. 相似文献
107.
The effect of dietary chitin on growth and nutrient digestibility in farmed Atlantic cod,Atlantic salmon and Atlantic halibut
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The effect of adding 0%, 1%, 2% and 5% chitin from prawn shells in the diets for Atlantic cod, Atlantic halibut and Atlantic salmon on growth was investigated. Nutrient digestibility and feed utilization was investigated in salmon and cod. Atlantic cod grew from 186 ± 29 to 383 ± 78 g (N = 960) over 13 weeks. Dietary chitin had no effect on length, weight, condition, liver size or specific growth rate (SGR). The apparent digestibility (ADC) for protein ranged from 84.7% to 86.5%, lipid between 88.8% and 93.1% and dry matter from 96.1% to 96.6%. Feed utilization varied between 1.08 and 1.11 and was not correlated with dietary chitin content. Atlantic salmon tripled their weight from 199 ± 9 to 615 ± 75 g (N = 480) during the 13 weeks. High inclusions of chitin (>1%) reduced both growth rate and condition. Protein and lipid ADC was negatively correlated with dietary chitin. Feed utilization ranged between 0.86 and 0.90 and was not significantly affected by dietary chitin. Faecal protein increased significantly with increasing dietary chitin, while faecal dry matter and lipid did not. Individually tagged Atlantic halibut grew from 1300 ± 470 to 2061 ± 714 g (N = 70) during 6 months. Individual growth rates varied within each group from being slightly negative to 0.81%·day?1. Diet had no significant effect on growth rates. Atlantic cod and Atlantic halibut seems unaffected by up to 5% chitin additions in the diet, while chitin >1% of diet negatively affects growth and nutrient utilization in Atlantic salmon. 相似文献
108.
M.B. LØFSTEDT 《Aquaculture Nutrition》2010,16(6):625-636
Winter mortality in hatchery reared oyster spat (Ostrea edulis) that received three different diets during the summer period was investigated. Oysters fed a natural type diet had a winter mortality of 18.3 ± 6.3% while oysters fed cultivated algae (a mixture of Tetraselmis suecica, Isochrysis galbana and Chaetoceros muelleri) had a mortality of 73.0 ± 9.7%. A group of oysters fed a mix between the two diets had a mortality of 54.7 ± 10.6%. Tissue samples were taken at the start of the experiment, after the summer period and after the winter period in order to determine growth and the content of glycogen and fatty acids. The glycogen content decreased for all groups during the winter but the decrease was highest in oysters fed the natural diet. This group also contained the largest variety of fatty acids, but there was no difference in the content of the essential fatty acids EPA, DPA and DHA between the groups. It is concluded that transplantation of spat to the sea in spring and early summer may reduce winter mortality since the feeding period on a more varied natural algal diet is prolonged compared to transplantation of spat later in the season. 相似文献
109.
Helene L.E. Midttun Marco A. Vindas Paul J Whatmore Øyvind Øverli Ida B. Johansen 《Journal of fish diseases》2020,43(8):863-875
Laboratory zebrafish are commonly infected with the intracellular, brain-infecting microsporidian parasite Pseudoloma neurophilia. Chronic P. neurophilia infections induce inflammation in meninges, brain and spinal cord, and have been suggested to affect neural functions since parasite clusters reside inside neurons. However, underlying neural and immunological mechanisms associated with infection have not been explored. Utilizing RNA-sequencing analysis, we found that P. neurophilia infection upregulated 175 and downregulated 45 genes in the zebrafish brain, compared to uninfected controls. Four biological pathways were enriched by the parasite, all of which were associated with immune function. In addition, 14 gene ontology (GO) terms were enriched, eight of which were associated with immune responses and five with circadian rhythm. Surprisingly, no differentially expressed genes or enriched pathways were specific for nervous system function. Upregulated immune-related genes indicate that the host generally show a pro-inflammatory immune response to infection. On the other hand, we found a general downregulation of immune response genes associated with anti-pathogen functions, suggesting an immune evasion strategy by the parasite. The results reported here provide important information on host–parasite interaction and highlight possible pathways for complex effects of parasite infections on zebrafish phenotypes. 相似文献
110.
Comparing the performance of cereal varieties in organic and non-organic cropping systems in different European countries 总被引:4,自引:4,他引:0
M. Przystalski A. Osman E. M. Thiemt B. Rolland L. Ericson H. Østergård L. Levy M. Wolfe A. Büchse H.-P. Piepho P. Krajewski 《Euphytica》2008,163(3):417-433
Top ranking varieties are tested in multiple environments before and after registration in order to assess their value for
cultivation and use (VCU testing). Recently, interest has increased in obtaining varieties specifically adapted to organic
farming conditions. This raised the question if an independent system of trials may be required for this purpose. To help
answering this question, through the exchange network of European cereal researchers SUSVAR (), a number of data sets of agronomic traits from barley, wheat and winter triticale, from trials performed in Denmark, Sweden,
The Netherlands, France, Switzerland, UK and Germany, were made available and analysed using an approach based on mixed models
involving parameters describing genetic correlation between the two types of experiments, i.e., organic and non-organic (high
or low input). Estimated variance components and correlations were used to evaluate response to selection and index selection.
The response to index selection was analysed as a function of the fraction of available trials assigned to the organic system.
The genetic correlations were interpreted in terms of ranking agreement. We found high genetic correlations between both systems
for most traits in all countries. Despite high genetic correlations, the chances of very good agreement in observed rankings
were moderate. Combining information from both organic and non-organic systems is shown to be beneficial. Further, ignoring
information from non-organic trials when making decisions regarding performance under organic conditions is a sub-optimal
strategy. 相似文献