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91.
Five-day-old pigs challenged with 10(3) pathogenic Escherichia coli (nalidixic acid resistant) showed no clinical signs of disease until subsequently weaned at three weeks. Dietary manipulation was shown to influence xylose malabsorption, diarrhoea and bacterial proliferation after weaning. Brief, but not continuous, contact with the diet before weaning markedly increased the severity of subsequent disease after weaning. Immunogenicity of the weaning diet was critical for the development of the disease. Two diets, identical except that in one the protein source (casein) had previously been enzymatically hydrolysed, were compared. Pigs fed the predigested diet showed no clinical signs of post weaning diarrhoea whereas those fed the untreated casein all developed diarrhoea. 相似文献
92.
D R Jones T J Gruffydd-Jones C R Stokes F J Bourne 《American journal of veterinary research》1992,53(4):457-465
Detection of autoantibody, complement, or both bound to RBC is an essential requirement for unequivocal diagnosis of immune-mediated hemolytic anemia in dogs. An enzyme-linked antiglobulin test was adapted for laboratory diagnosis of this disease. The refinement and routine use of this assay have allowed further observation of the pathogenesis of the disease process. In particular, degree of hemolysis can be related to the degree of RBC sensitization associated with primary immune-mediated hemolytic anemia, and this correlation is highest for IgG autoantibody. Results indicate that autoantibody isotype might have an important role in the hemolytic process. 相似文献
93.
A national serological survey to verify Australia's freedom from porcine reproductive and respiratory syndrome 总被引:4,自引:0,他引:4
MG GARNER LJ GLEESON PK HOLYOAKE RM CANNON WJ DOUGHTY 《Australian veterinary journal》1997,75(8):596-600
Objective To provide serological data to support Australia's claim of freedom from porcine reproductive and respiratory syndrome.
Design A national serological survey was designed to provide 99% confidence of detecting at least one infected pig herd in Australia, assuming that at least 5% of herds would have been exposed to porcine reproductive and respiratory syndrome virus and that at least 25% of the 'finisher' pigs in these herds would have antibodies to the virus.
Procedure A two-stage testing regime was used. All samples were tested with a commercially available enzyme-linked immunosorbent assay. If assay reactions were found, all samples from the herd were to be tested using the indirect immunofluorescence antibody assay.
Results Of the 875 samples from 163 herds from all States in Australia, there was some evidence of reactivity in only four samples from four herds on the enzyme-linked immunosorbent assay. Further testing using the indirect immunofluorescence antibody assay according to the study protocol demonstrated that the reactions were not due to the presence of specific porcine reproductive and respiratory syndrome virus antibodies in the sera.
Conclusion The results of this study support the view that Australian pigs are free of porcine reproductive and respiratory syndrome virus. 相似文献
Design A national serological survey was designed to provide 99% confidence of detecting at least one infected pig herd in Australia, assuming that at least 5% of herds would have been exposed to porcine reproductive and respiratory syndrome virus and that at least 25% of the 'finisher' pigs in these herds would have antibodies to the virus.
Procedure A two-stage testing regime was used. All samples were tested with a commercially available enzyme-linked immunosorbent assay. If assay reactions were found, all samples from the herd were to be tested using the indirect immunofluorescence antibody assay.
Results Of the 875 samples from 163 herds from all States in Australia, there was some evidence of reactivity in only four samples from four herds on the enzyme-linked immunosorbent assay. Further testing using the indirect immunofluorescence antibody assay according to the study protocol demonstrated that the reactions were not due to the presence of specific porcine reproductive and respiratory syndrome virus antibodies in the sera.
Conclusion The results of this study support the view that Australian pigs are free of porcine reproductive and respiratory syndrome virus. 相似文献
94.
Concentrations of uterine luminal prostaglandins in mares with acute and persistent endometritis 总被引:1,自引:0,他引:1
Intrauterine infusion of 1 per cent oyster glycogen solution was used to induce acute endometritis in four genitally normal mares. Numbers of viable neutrophils recovered in uterine washings had increased by 1 h after infusion and remained elevated for at least 72 h. There was a significant correlation between numbers of viable neutrophils and total protein concentrations and between prostaglandin (PG)F and PGE2 concentrations in washings. There was also a significant relationship between concentrations of 15-keto-13, 14-dihydro PGF2 alpha in plasma and PGF in washings. Intrauterine concentrations of PGF were influenced by cycle stage and in turn the induced acute endometritis interfered with normal ovarian function. Mares with persistent endometritis had significantly higher concentrations of PGF and total protein and percentage of neutrophils and mononuclear cells in washings than normal mares. White blood cells from mares were capable of producing PGF and PGE2 in vitro. 相似文献
95.
Cellular and humoral defence mechanisms in mares susceptible and resistant to persistent endometritis 总被引:2,自引:0,他引:2
Both random and directional migration of blood neutrophils from 9 mares susceptible to persistent endometritis were significantly less (p less than 0.05) than neutrophils from 8 resistant mares. Serum from susceptible mares had significantly more (p less than 0.01) chemotactic activity than serum from resistant mares. Although phagocytosis of yeast blastospores by blood neutrophils from 4 resistant and 3 susceptible mares was similar, uterine neutrophils from susceptible mares were significantly worse (p less than 0.01) at phagocytosis than uterine neutrophils from resistant mares. Uterine washings from 17 susceptible mares were significantly better at opsonising yeast blastospores than washings from 14 resistant mares; however, washings from both groups had a similar ability to promote killing of S. zooepidemicus by neutrophils. When an immunologically non-specific endometritis was induced, washings from 3 susceptible mares were significantly worse at promoting bactericidal activity by 144 h than washings from 4 resistant mares (p less than 0.01). Haemolytic complement activity was significantly greater (p less than 0.001) in washings from 17 susceptible mares than from 14 resistant mares. Induction of acute endometritis resulted in high levels of haemolytic complement activity in 2 of 3 susceptible mares at 24 and 144 h, but only in small increases in 4 resistant mares. Thus, some abnormalities in neutrophil function were detected and a possible defect in promotion of neutrophil bactericidal activity by uterine secretions from susceptible mares but there was no evidence for any deficiency in haemolytic complement activity. 相似文献
96.
97.
The intestinal immune system and oral vaccination 总被引:1,自引:0,他引:1
98.
Long-term growth and yield effects of respacing natural regeneration of Sitka spruce in Britain 总被引:2,自引:0,他引:2
Stands of Sitka spruce (Picea sitchensis (Bong.) Carr.) originating from natural regeneration can be extremely dense with high mortality, poor growth form and low volume production. Although costly, respacing (pre-commercial thinning) can reduce resource competition for the remaining trees, altering the final crop produced. Three experiments were established to examine the effect of respacing 1–2 m tall trees to different target densities. The impact on stand growth and yield was measured 11–17 years after respacing, and the longer-term impact was modelled to year 50. Unrespaced control treatments self-thinned at a similar and constant rate at two sites. At the third, extremely high initial density resulted in a higher rate of self-thinning and lower density after 11 years. Wider respacing treatments resulted in larger mean tree diameter, but there was no significant effect of respacing on stand volume 11–17 years after respacing; greater diameter growth did not compensate for low tree number. Results indicate a volume penalty associated with delaying respacing until trees were 4 m tall, but this treatment was unreplicated. Modelled stand volume in year 50 was higher for the 2.6 m × 2.6 m respacing treatment than for the 1.8 m × 1.8 m, 2.1 m × 2.1 m or 3.3 m × 3.3 m treatments. However, open-grown conditions may reduce timber quality compared to closer spacing treatments. The results are presented using a stand density management diagram for Sitka spruce growing in Canada and support recent suggestions that British stands have a shallower size–density relationship than Canadian stands. 相似文献
99.
100.
A comparative review of fisheries management experiences in the European Union and in other countries worldwide: Iceland,Australia, and New Zealand
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Paul Marchal Jesper Levring Andersen Martin Aranda Mike Fitzpatrick Leyre Goti Olivier Guyader Gunnar Haraldsson Aaron Hatcher Troels Jacob Hegland Pascal Le Floc'h Claire Macher Loretta Malvarosa Christos D Maravelias Simon Mardle Arantza Murillas J Rasmus Nielsen Rosaria Sabatella Anthony D M Smith Kevin Stokes Thomas Thoegersen Clara Ulrich 《Fish and Fisheries》2016,17(3):803-824
This study compares the details and performance of fisheries management between the EU and a selection of other countries worldwide: Iceland, New Zealand, and Australia, which are considered in many respects to be among the most advanced in the world in fisheries management. Fisheries management in the EU, Iceland, Australia, and New Zealand has developed following different paths, despite being based on similar instruments and principles. Iceland, Australia, and New Zealand have been at the forefront of developing management practices such as stakeholder involvement, legally binding management targets (Australia, New Zealand), individual transferable quotas, and discard bans (Iceland, New Zealand). The EU has since the beginning of the 21st century taken significant steps to better involve stakeholders and establish quantitative targets through management plans, and a landing obligation is gradually being implemented from 2015 onward. The management of domestic fisheries resources in Australia, New Zealand, and Iceland has, overall, performed better than in the EU, in terms of conservation and economic efficiency. It should, however, be stressed that, compared to Australia, New Zealand, and Iceland, (i) initial over‐capacity was more of an issue in the EU when management measures became legally binding and also that (ii) EU has been progressive in developing common enforcement standards, on stocks shared by sovereign nations. The situation of EU fisheries has substantially improved over the period 2004–2013 in the northeast Atlantic, with fishery status getting close to that in the other jurisdictions, but the lack of recovery for Mediterranean fish stocks remains a concern. 相似文献