Microstructure and texture of fresh and smoked Atlantic salmon, Salmo salar L., fillets from fish reared and slaughtered under different conditions     

Sjofn Sigurgisladottir  Margret S. Sigurdardottir  Helga Ingvarsdottir  Ole J. Torrissen  Hannes Hafsteinsson 《Aquaculture Research》2001,32(1):1-10

This study was carried out to examine differences in microstructure and texture of fresh and smoked farmed Atlantic salmon Salmo salar L. fillets with different biological characteristics. The left fillet was analysed fresh and compared with the salted and smoked right fillet from each individual fish. Light microscopy and image analysing techniques were used to study both transversal and longitudinal sections of the muscle. The fish muscle fibres shrank during the salting and smoking process, but sarcomere length did not change. After smoking, a considerable number of fat globules were dispersed among the muscle fibres. The biological characteristics studied were based upon diploid and triploid fish held in both sea cages and land‐based tanks. Different starvation times were used and one group was stressed during slaughter. The cross‐sectional area of muscle fibres from triploid fish was found to be larger than from diploid fish, both in fresh and smoked fillets.  相似文献   

Optical properties of the pineal window of Atlantic salmon (Salmo salar L.)     

Trond Nordtug  Ole Kristia Berg 《Fish physiology and biochemistry》1990,8(6):541-546

The spectral composition and intensity of light penetrating different parts of fresh preparations of the upper part of the skull of Atlantic salmon (Salmo salar) (fork length 25–30 cm) was investigated. All measurements were made in an aqueous medium, by moving the tip of an optical fibre in a three dimensional lattice below preparations that were illuminated by a parallel light source from above. The intensity of the transmitted light showed a well-defined maximum just below the pineal groove. Light that penetrated the skull from a source vertically above was refracted to produce a focusing point in the approximate position of the pineal body. Light projected from angles of 45° relative to the vertical position was only slightly (25%) attenuated, thus indicating a wide acceptance angle. There was an almost uniform transmission of light (of 3%) between 500 and 700 nm. The transmittance of UV light (350 nm) was about 10% of that of green light. These differences are small when compared with the intensity range reported for the pineal light receptors. The transmission properties are discussed in relation to the known diurnal changes in the spectral composition of natural light.  相似文献   

Restoration of a channelized reach of the River Gelså, Denmark: Effects on the macroinvertebrate community     

Nikolai Friberg  Brian Kronvang  Lars M. Svendsen  Hans Ole Hansen  Mogens B. Nielsen 《水产资源保护:海洋与淡水生态系统》1994,4(4):289-296

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Von Bandt's Fish Catching Methods of the World (Fourth Edition)     

Ole Arve Misund 《Fish and Fisheries》2007,8(2):162-163

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猪的最佳维生素营养   总被引：1，自引：0，他引：1  

卢建华  覃矜 《国外畜牧学(猪与禽)》2002,(1):22-24

猪的维生素需要量是动态的 ,是随猪种、营养状况、饲养管理方式等的不同而不同的 ,维生素需要量推荐值也因人们维生素功能的认识不断加深而有所不同。因此 ,需要不断地对维生素需要量推荐值进行更新  相似文献   

Noninvasive assessment of the facilitation of the nociceptive withdrawal reflex by repeated electrical stimulations in conscious dogs     

Bergadano A  Andersen OK  Arendt-Nielsen L  Spadavecchia C 《American journal of veterinary research》2007,68(8):899-907

OBJECTIVE: To investigate the facilitation of the nociceptive withdrawal reflex (NWR) by repeated electrical stimuli and the associated behavioral response scores in conscious, nonmedicated dogs as a measure of temporal summation and analyze the influence of stimulus intensity and frequency on temporal summation responses. ANIMALS: 8 adult Beagles. PROCEDURES: Surface electromyographic responses evoked by transcutaneous constant-current electrical stimulation of ulnaris and digital plantar nerves were recorded from the deltoideus, cleidobrachialis, biceps femoris, and cranial tibial muscles. A repeated stimulus was given at 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, and 1.1 x I(t) (the individual NWR threshold intensity) at 2, 5, and 20 Hz. Threshold intensity and relative amplitude and latency of the reflex were analyzed for each stimulus configuration. Behavioral reactions were subjectively scored. RESULTS: Repeated sub-I(t) stimuli summated and facilitated the NWR. To elicit temporal summation, significantly lower intensities were needed for the hind limb, compared with the forelimb. Stimulus frequency did not influence temporal summation, whereas increasing intensity resulted in significantly stronger electromyographic responses and nociception (determined via behavioral response scoring) among the dogs. CONCLUSIONS AND CLINICAL RELEVANCE: In dogs, it is possible to elicit nociceptive temporal summation that correlates with behavioral reactions. These data suggest that this experimental technique can be used to evaluate nociceptive system excitability and efficacy of analgesics in canids.  相似文献   

Spatial variability of glyphosate mineralization and soil microbial characteristics in two Norwegian sandy loam soils as affected by surface topographical features     

Marianne Stenrød  Marie-Paule Charnay  Ole Martin Eklo 《Soil biology & biochemistry》2006,38(5):962-971

The aim of this study was to investigate the possible influence of surface topographical features on the spatial variability of glyphosate degradation and some microbial characteristics in sandy loam soil. Soil samples were taken from the ploughed layer across an agricultural field after seedbed preparation for grain (Grue site), and down to 1 m depth under a ridge tilled field (Målselv site), both sites having similar soil textural characteristics (sandy loam soil). Laboratory experiments were performed looking at glyphosate mineralization and soil microbial activity at the Grue site, as well as microbial biomass, activity and substrate utilization patterns at the Målselv site. Microbial biomass and activity decreased, and substrate utilization patterns changed with increasing soil depth, reflecting naturally occurring changes in quantity and quality of soil organic carbon. Further, our results show that considerable spatial heterogeneity in the degradation rate of glyphosate and general carbon utilization exists even across small areas within a single agricultural field. This horizontal variability was observed over several spatial scales, and could not be clearly explained. It evidently arose from differences in environmental factors affecting microbial activity and growth, and topographical features controlling redistribution of water and matter flow patterns were correlated to the investigated soil microbial variables.  相似文献   

Cleaning heavy metal contaminated soil with soluble humic substances instead of synthetic polycarboxylic acids     

Ole K. Borggaard  Peter E. Holm  Julie K. Jensen  Mohsen Soleimani  Bjarne W. Strobel 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(6):577-581

Abstract

Soils contaminated with heavy metals constitute a serious and widespread ecological problem but to clean such soils requires strong chemicals such as polycarboxylates; frequently ethylenediaminetetraacetic acid and nitrilotriacetic acid are used. However, these compounds are synthetic and toxic and their replacement by natural products such as soluble humic substances as washing agents for cleaning heavy metal polluted soils would be environmentally very attractive. In fact, such a replacement seems possible at least on cadmium and copper contaminated soil inasmuch as humic substances, depending on the concentration, were found to extract up to 45% and 54% of total cadmium and copper from a highly contaminated calcareous soil. Even though higher amounts of the two metals were extracted by ethylenediaminetetraacetic acid and nitrilotriacetic acid, the humic substances undoubtedly extracted the most reactive fractions. However, the humic substances extracted only 4% of total lead and 17% of total nickel, whereas the percentages for the synthetic polycarboxylates were about 30% for nickel and lead. Ethylenediaminetetraacetic acid and nitrilotriacetic acid may therefore be replaced by humic substances as washing agents for cadmium, copper and maybe nickel contaminated soils, whereas they seem unsuited for cleaning lead contaminated soils, at least if the soils are as calcareous as the soil tested.  相似文献   

Evaluation of an enzyme-linked immunosorbent assay for serological surveillance of infection with Actinobacillus pleuropneumoniae serotype 5 in pig herds     

Klausen J  Andresen LO  Barfod K  Sørensen V 《Veterinary microbiology》2002,88(3):223-232

An indirect enzyme-linked immunoassay for serological surveillance of infection of pigs with Actinobacillus pleuropneumoniae (Ap) serotype 5 was developed. The antigen used was prepared from Ap serotype 5b strain L20. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed that the antigen contained high molecular weight lipopolysaccharide (LPS) and presumably also capsular polysaccharide (CP). The Ap serotype 5 ELISA was tested using sera from pigs experimentally infected with the 12 different Ap serotypes of biotype 1 and with sera from herds naturally infected with Ap serotypes 5, 6, 7 and 12. Cross-reactions were shown in one pig from a herd naturally infected with Ap serotype 7 and in one pig from a herd naturally infected with Ap serotype 12. The herd sensitivities of the Ap5 ELISA and a complement fixation test (CFT) were both estimated to 1.0, on the basis of serum samples from six herds naturally infected with Ap serotype 5. The herd specificities of both tests were estimated to 0.98, based on serum samples from 123 pig herds (10 samples from each herd) from the Danish specific pathogen-free (SPF) programme for pig production.  相似文献   

Feed-induced Changes in the Transport of Butyrate,Sodium and Chloride Ions Across the Isolated Bovine Rumen Epithelium     

Jakob Sehested  Jens Bech Andersen  Ole Aaes  Niels Bastian Kristensen  Lars Diernæs  Peter Detlef Møller 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(1):47-55

A short-chain fatty acid (SCFA) burst feeding strategy to dry cows (periodically high SCFA concentration in the ruminal fluid) has been hypothesized to increase the ruminal surface area and absorptive capacity. The present paper deals with the effects of a SCFA burst feeding strategy on epithelial transport function in dry cows. The epithelial transport capacity for [¹⁴C]butyrate and Na⁺ across the rumen epithelium in vitro was significantly increased by the SCFA burst feeding strategy, compared with the controls. The transport of Cl^- was significantly increased by the SCFA burst feeding strategy at the high feeding level, but non-significantly decreased at the low feeding level. The increase in transport capacity could not be attributed to changes in epithelial resistance, to the concentration of Na⁺/K⁺-ATP-ase or to the epithelial surface area and structure (data on epithelial surface area and structure were published by Andersen et al., Report No. 23 from the National Institute of Animal Science, Denmark, 1994). The observed changes in transport must reflect a change in either composition of the cell membranes or processes that facilitate transport through the cell, including metabolic processes. The presented results support the existence of a saturable SCFA transport system in the epithelial cells and the results show that the capacity of this transport system can be the subject for feed-induced regulation.  相似文献