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1.
The welfare of an animal is ensured if it is able to fully satisfy its essential species‐typical needs in all functional aspects of behaviour. In mink, stereotypies and apathy, internal and/or external injuries as well as increased susceptibility to disease have been known to occur as a result of chronic stress. The non‐invasive method of analysing faecal cortisol metabolites (FCM) allows conclusions to be drawn about the stress level in the respective housing system. The objective of this study is to find out how the cortisol metabolites content in the faecal changes with increasing age of the mink under semi‐natural housing conditions. Thus, 40 American mink (Neovison vison) were housed in two outdoor enclosures imitating natural conditions. Throughout the entire study (13th to 32nd week of life), faecal samples were collected to measure cortisol metabolites. No differences in FCM concentrations between the two outdoor enclosures were found. In the young mink lower, less fluctuating FCM levels were found than in older animals. After the first faecal collection in the 13th/14th week of life, the level of metabolites decreased slightly (p = 0.032; 17th/18th week). From the 22nd/23rd week onwards until the 30th/31st week, shortly before the animals were pelted, continuously increasing concentrations were then measured. Increasing FCM levels with advancing age of the animals are probably attributable to the onset of sexual maturity and/or the respective season. This has to be taken into account in future studies using this method for assessing welfare and when comparing different mink housing systems.  相似文献   
2.
Samples of the two muscles were taken from 8 Landrace fattened pigs, affected with pale, soft exudative meat, during stunning and 15, 30, 45 and 60 minutes after death; also 2, 3, 6, 12, 24 and 48 hours after slaughter, with storage at 20 degrees C for the first six hours and 2-5 degrees C subsequently. Considerable changes were found during the first hour after death, or even in samples taken during stunning, in longissimus dorsi samples. These consisted of destruction of mitochondria and sarcoplasmic reticulum, breakdown of cell membranes, liberation of clumps of fibre protein, disappearance of glycogen, rigor and destruction of capillaries. Such changes would account for the features of pale, soft exudative meat such as water loss, brief rigor, pale colour, deficiency of energy-rich phosphates. By contrast, in the masseter muscles of the same animal these changes did not occur until later, or were in port absent. In both muscle the breakdown of fibres took place by destruction of the "I" bands and the "Z" strips, and this process also commenced in longissimus dorsi before masseter.  相似文献   
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A 7‐week‐old male pig was presented with signs of a central nervous system disorder. An MRI of the head and cervical spine was performed immediately after euthanasia. The MRI revealed multifocal bilaterally symmetric T2‐weighted hyperintense lesions in the brain and spinal cord, likely due to a toxic metabolic process. Histopathological examination supported the MRI findings and confirmed the diagnosis of edema disease due to Shiga‐like toxin produced by Escherichia coli. This is the first case published of the MRI findings in an edema disease affected pig.  相似文献   
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Quantitative pathohistological investigations were performed on 300 samples of five different myocardial regions from 50 pigs with had suffered stress-related myocardial insufficiency on their transport to the slaughterhouse (transport exhaustion). The findings were compared to 1,200 myocardial samples from 200 clinically intact pigs for slaughter. Animals with transport-related damage exhibited with significance more and more severe inflammatory and degenerative myocardial alterations, such as round-cell infiltration, fiber necrosis, calcification, and fat infiltration. Many of these lesions had been manifest already prior to transport. Myocardially predamaged pigs were less capable than others of sustaining transport stress and were more predisposed to cardiac failure. Stress-related cardiovascular insufficiency, consequently, depended not only on direct stress but also on the general health condition of the myocardium. Causes and pathogenetic relevance of these alterations are discussed in some detail.  相似文献   
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The objective of this study was to define the patterns of organogenesis and foetal haemodynamics during the normal gestation of healthy agoutis (Dasyprocta prymnolopha) kept in captivity. Thirty pregnant agoutis that ranged in size from small to medium and weighed between 2.5 and 3 kg underwent B‐mode and Doppler ultrasonography for the biometric evaluation of the foetal organs. The foetal aortic blood flow proved to be predominantly systolic, and the measured flow velocity was 78.89 ± 2.95 cm/s, with a maximum pressure gradient of 2.12 ± 0.27 mmHg. The liver was characterized by its large volume, occupying the entire cranial aspect of the abdominal cavity, and it was associated cranially with the diaphragm and caudally with the stomach. The flow velocity in the portal vein was estimated to equal 12.17 ± 2.37 cm/s, with a resistivity index of 0.82 ± 0.05. The gallbladder was centrally located and protruded cranially towards the diaphragm. The spleen was visualized as an elongated structure with tapered cranial and caudal extremities, and the foetal kidneys were visualized bilaterally in the retroperitoneal region, with the right kidney positioned slightly more cranially than the left. The morphological characterization and hemodynamic analysis of the foetal organs of black‐rumped agoutis via B‐mode and Doppler ultrasonography allow determination of the vascular network and of reference values for the blood flow required for perfusing the anatomical elements essential for maintaining the viability of foetuses at different gestational ages.  相似文献   
9.
Although koi herpesvirus (KHV) has a history of causing severe economic losses in common carp and koi farms, there are still no treatments available on the market. Thus, the aim of this study was to test exopolysaccharides (EPS) for its antiviral activity against KHV, by monitoring inhibition and cytotoxic effects in common carp brain cells. These substances can be easily extracted from extracellular algae supernatant and were identified as groups of sulphated polysaccharides. In order to reach this aim, Arthrospira platensis, which is well known for its antiviral activity of intra‐ and extracellular compounds towards mammalian herpesviruses, was investigated as standard organism and compared to commercial antiviral drug, ganciclovir, which inhibits the viral DNA polymerization. The antiviral activity of polysaccharides of A. platensis against KHV was confirmed in vitro using qualitative assessment of KHV life cycle genes, and it was found by RT‐PCR that EPS, applied at a concentration of >18 μg mL?1 and a multiplicity of infection (MOI) of 0.45 of KHV, suppressed the viral replication in common carp brain (CCB) cells even after 22 days post‐infection, entirely. Further, this study presents first data indicating an enormous potential using polysaccharides as an additive for aquacultures to lower or hinder the spread of the KHV and koi herpesvirus disease (KHVD) in future.  相似文献   
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