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11.
Birthe M. Damgaard Tove N. Clausen Søren K. Jensen Ricarda M. Engberg 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(1):19-29
The effects of different dietary levels of marine lipids in the diets with a constant distribution of metabolizable energy (ME) on protein, fat and carbohydrate were investigated in male mink kits in the growing-furring period during 2 consecutive years. The physiological investigations included 15 males per experimental group, each consisting of about 75 males. Fat herring and mackerel scrap were used in amounts resulting in levels of marine lipids of 30, 50 and 70% of total dietary lipid, respectively. Defatted herring scrap was used in proportions of 12, 23 and 32% in the diets. Haematocrit value, haemoglobin concentration, number of erythrocytes, leucocytes and platelets, plasma activities of alanine aminotransferase (ALAT), aspartate aminotransferase (ASAT) and creatine kinase (CK), concentrations of tocopherols in plasma, liver and adipose tissue, composition of fatty acids (FA) in liver and adipose tissue, body weight, weight of liver and heart in relation to body weight, and liver fat content were studied. The number of platelets decreased with an increasing proportion of marine lipids of total content of dietary lipids. A high intake of fatty fish products had no influence on the health status of the animals evaluated by haematological and clinical-chemical analyses, vitamin E status and FA composition in growing-furring male mink. No negative effects on the health of the animals were demonstrated when feeding with defatted herring scrap. 相似文献
12.
Bodil Sørensen Tove N. Clausen Søren Wamberg Otto Hansen 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(2):148-154
The influence of time of weaning on weight changes, and on hormone and electrolyte status in domestic mink (Mustela vison) dams raising at least five kits per litter was examined. The kits were weaned at either day 42 (group 1) or day 49 (group 2) after birth. The dams were weighed and urine and blood were sampled from day 29 to day 56 after delivery. A considerable loss of dams' body weight, constituting 6.3% in group 1 and 8.1% in group 2, was noticed on the day after weaning, indicating a greatly reduced food consumption on the day of weaning. No changes in plasma aldosterone and no significant decrease in urinary sodium concentration were seen in dams after removal from their litters, whereas, irrespective of time of weaning, urinary sodium and chloride concentrations were halved a few days after weaning compared with the other group. The plasma cortisol concentration was high before and during weaning and was nearly halved 1 week after weaning, implying less strain on the dams after weaning. It is concluded that the weaning period is a most vulnerable and stressful period to the dams irrespective of the actual time of weaning. 相似文献
13.
In 2002 the Danish Minister of Environment initiated a process to investigate the possibilities of establishing national parks in Denmark. For this purpose experts were mobilised to investigate the status and potentials of the areas in question.The national park process was extensive in scope and complex, and in theory such complexity is assumed to make it difficult for non-experts to understand all the relevant aspects of policy. This exclusion of non-experts may lead to scientification of politics. Furthermore politicisation of science might occur as experts might advocate political interests disguised as objective science, and policy-makers might select results that further their own interests. As a result policy-makers risk losing a source of legitimacy, scientists risk losing credibility and the citizens risk losing the possibility to hold policy-makers accountable for their decisions, which puts democracy at risk.This paper examines the accountability relationships that experts were a part of in the national park process. These include accountability towards the employer, towards the buyer and towards the general public. The purpose is to determine if these relationships were adequate to circumvent the problems associated with scientification of politics and to discuss how accountability relationships and thereby democracy could be strengthened.The empirical analysis shows that in the national park process experts were mainly accountable towards the National Forest and Nature Agency. There were formal accountability relationships between the experts and the local steering committees and the national advisory group, but these relationships were less significant. Moreover, despite the fact that the process was deemed unusually open to the public by the participants, the relationship between experts and the public cannot be characterised as an accountability relationship and could have been improved by including experts in the deliberative fora of the process. 相似文献
14.
Hanne Hjorth Tønnesen Ivar Mysterud Jan Karlsen Olav M. Skulberg Carl M. M. Laane Trond Schumacher 《Veterinary research communications》2010,34(4):347-357
Alveld is a disease in lambs of domestic sheep (Ovis aries L.), characterized by a combination of photosensitivity and liver damage. Generation of singlet oxygen play a major role
in phototoxicity reactions. The compound phylloerythrin (phytoporphyrin) is so far assumed to be the main photodynamic agent
in hepatogenous photosensitivity diseases in sheep. Phylloerythrin is a potent photosensitizer and an efficient source of
singlet oxygen. The compound accumulates in the peripheral circualtion upon liver damage. Liver dysfunction is also likely
to cause an increase in the blood level of bilirubin. Formation of singlet oxygen by bilirubin is reported. In the present
work the photosensitizing potential of serum has been measured and related to the bilirubin- and phylloerythrin levels in
lambs suffering from alveld and in clinically healthy controls. The singlet oxygen level of the serum was taken as a measure
of the photosensitizing potential. The observed singlet oxygen values in serum from alveld lambs were significantly higher
than the corresponding values observed in clinically healthy control lambs. This indicates that the serum of the alveld lambs
contains an elevated concentration of photosensitizer. The singlet oxygen level was not correlated to the concentration of
bilirubin or phylloerythrin. The results indicate that the photosensitizing mechanism is quite complex and may involve other
sensitizer(s) than phylloerythrin. 相似文献
15.
Andersen MI Castro-Tirado AJ Hjorth J Moller P Pedersen H Caon N Cairos LM Korhonen H Osorio MR Perez E Frontera F 《Science (New York, N.Y.)》1999,283(5410):2075-2077
An optical spectrum of the afterglow from the unusually bright gamma-ray burst GRB 990123 obtained on 24.25 January 1999 universal time showed an absorption system at a redshift of z = 1.600. The absence of a hydrogen Lyman alpha forest sets an upper limit of z < 2.17, whereas ultraviolet photometry indicates an upper limit of z < 2.05. The probability of intersecting an absorption system as strong as the one observed along a random line of sight out to this z is at most a few percent, implying that GRB 990123 was probably at z = 1. 600. Currently favored cosmological parameters imply that an isotropic energy release equivalent to the rest mass of 1.8 neutron stars (4.5 x 10(54) erg) was emitted in gamma rays. Nonisotropic emission, such as intrinsic beaming, may resolve this energy problem. 相似文献
16.
This study illustrates the embryo development of the spotted wolffish (Anarhichas minor Olafsen), an interesting candidate for cold‐water aquaculture. The egg morphology (semitransparent, yellow‐white with numerous oil droplets in the yolk), size (5.4–6.5 mm) and long embryogenesis (c. 800–1000 d°, depending on temperature) of A. minor are very similar to Anarhichas lupus. Cleavage is slow, and the first cell divisions take place at 12 h at 8°C. After 12 days the 2‐mm embryo with the first somites is laid down and the blastopore starts closing. The fat globules in the yolk fuse into one after 22 days, and after 30 days eye pigmentation is noticeable. After 44 days, eye pigmentation is strong, the digestive tract folded and a green gall bladder can be noted in the now 11‐mm‐long embryo. One week later the blood is brightly red, the intestine is pigmented and the lower jaw is well developed. Premature hatching may occur from this stage. After 58 days vascularization of the yolk is complete, capillaries are noted in the fin fold, the first ray rudiments are established in the tail and pectoral fins, and the four gill arches are covered by the operculum. The preanal finfold is reduced after 72 days, stomach and gill filaments are formed, and six pigmented rows are noted on the 17‐mm‐long embryo body. After 86 days all fin rays are seen and the digestive tract is intensely pigmented and folded. Hatching (normal) starts after 110 days and may last for 2–3 weeks. Late embryos and early larvae of A. minor have more distinct bands of pigment along the body compared with the closely related A. lupus. An increase in both length and weight of the embryos in individual batches occurs during the hatching period. 相似文献
17.
In order to define temperature regimes that could benefit successful production of spotted wolffish (Anarhichas minor) juveniles, experiments with offspring from two different females were carried out. The larvae were fed a new formulated feed or a commercial start‐feed for marine fish, both of which have given high survival rates. In the first experiment newly hatched larvae were fed at constant 6 °C, 8 °C, 10 °C and 12 °C as well as at ambient seawater temperature (2.9–4.5 °C) during 63 days. High survival, 90% to 96%, was registered at ambient and most constant temperature regimes, whereas in the 12 °C groups survival was reduced to 80%. Growth rate (SGR) was very low, 1.8% day?1, at the low ambient temperatures. Growth rate was positively correlated with temperature and varied between 3.1% day?1 to 4.7% day?1, from 6 °C to 12 °C. In the second experiment, set up to include potential detrimental temperatures and study beneficial effects of a more restricted, elevated first‐feeding temperature regime, the larvae were fed at constant 8 °C, 10 °C, 12 °C, 14 °C and 16 °C until 30 days post hatch, followed by constant 8 °C for the next 33 days. In this experiment, low survival, 25% and 2.0%, was registered at 63 days post hatch when larvae were reared initially at 14 °C and 16 °C respectively. The survival of the larvae at the other temperature regimes varied from 47% to 64%, highest survival rate (64%) was found at 8 °C. The lowest specific growth rate, 2.6% day?1, was noted in the 16 °C group. At constant 8 °C to 14 °C (regulated to 8 °C), the SGR varied from 4.45% day?1 to 5.13% day?1. The larvae grew faster in the experiment when initially comparable temperatures (8 °C, 10 °C and 12 °C) were regulated to constant 8 °C after 30 days compared with the first experiment where feeding was carried out at the same constant temperatures (8 °C, 10 °C and 12 °C) during the whole experimental period. 相似文献
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19.
Eleven free amino acids were identified in the grass weed loose silky-bent (Apera spica-venti) after exposure to four rates of the thiocarbamate herbicide prosulfocarb. A new HPTLC method was developed for quantification of amino acids in raw plant extracts. A pattern of significant changes in the content of glutamine, glycine, alanine, and proline due to exposure were detected. The content of all four amino acids increased at increasing exposure rates. Quantitative analyses 7 and 21 days after herbicide application showed that over time the amount of proline increased, the alanine and glycine content decreased, and that at high exposure rates the amount of glutamine increased. Visual effects were evaluated and the biomass was measured. The visual symptoms increased and the biomass decreased with increasing exposure rates. A significant correlation between the changes in the content of the four amino acids and the visual effects and the biomasses were found. 相似文献
20.
Forest policy in Denmark aims to increase the environmental values of forests. For policy implementation it is essential to
know how to motivate private owners. Based on a survey among private forest owners in Denmark, four types of owners have been
identified, clustered according to their forest management attitudes and practices: (1) the production-oriented owner, (2)
the classic forest owner, (3) the environmental/recreational owner, and (4) the indifferent forest owner. Owners in Clusters
1 and 2 are mainly motivated by financial and wood production aspects, whereas owners in Cluster 3 are to a greater extent
motivated by environmental and recreational aspects. Cluster 4 is the least motivated cluster. For effective policy intervention,
the clusters should be addressed by different means. Owners in Clusters 1 and 2 should be met on their agricultural-production
logic, Cluster 3 on their interest to improve environmental values, whereas owners in Cluster 4 might mainly be interested
in passive nature management solutions. 相似文献