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291.
The nematode parasite Angiostrongylus vasorum is a source of increasing concern in several parts of the world, where it causes significant disease in dogs. Wild canids, especially foxes, are likely to have a role in the epidemiology of canine infection, and the parasite could also affect fox health and population dynamics. The heart and pulmonary vasculature of 546 foxes culled mostly by gamekeepers in Great Britain in 2005–2006 were examined by dissection and a modified flushing technique. Forty foxes were found to be infected, giving an overall prevalence in the UK fox population of 7.3% (5.3–9.9). Prevalence varied widely between regions, from 0% (0–3) in Scotland and northern England to 23% (16–32) in south-east England. This closely matches the perceived incidence of disease in dogs, which is commonly diagnosed in the south-east but rarely in the north. In the Midlands, where disease has recently appeared in dogs, prevalence in foxes was 4.8% (2–11). Close geographical overlap of parasite distribution in foxes and dogs does not necessarily indicate an important wildlife reservoir of infection, but does suggest that A. vasorum might be spreading northwards. The hearts of infected foxes had thicker right ventricles than those of uninfected foxes, suggesting that the parasite could affect fox health and fitness. Burdens ranged from 1 to 59 adult nematodes. Sex, age and body condition were not significantly associated with infection. Eucoleus aerophilus and Crenosoma vulpis, nematode parasites of the respiratory system, were found in 213 and 11 foxes respectively, with slightly higher prevalence of E. aerophilus in the south and east. No specimens of the heartworm Dirofilaria immitis were found, giving an upper 95% confidence interval for prevalence of 0.84%.  相似文献   
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A Holstein cow was presented for inspiratory dyspnea. Endoscopic evaluation revealed swollen arytenoids and a presumptive diagnosis of bilateral arytenoidal chondritis was made. A partial arytenoidectomy was performed, the right arytenoid was submitted for histopathology, and a diagnosis of laryngeal lymphoma was made. Due to the poor prognosis, the cow was euthanized.  相似文献   
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Forests in north-eastern New South Wales have often been the focus of controversy. The tension between production and preservation continues and hampers current negotiations for a code of practice for private native forestry. The structure of many private forests reflects past mismanagement, and silvicultural intervention would benefit both conservation and production objectives, but such intervention is rarely financially viable. This paper sets out the economic and ecological basis for private native forestry. Both the timber industry and nature-based tourism are major contributors to the local economy, and both rely in part on private native forests. Draft regulations currently under negotiation do not offer incentives for improved private forest management.
V. Alex JayEmail:
  相似文献   
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OBJECTIVES: To assess vitamin A supplementation (VAS) coverage of children aged 6-59 months and the factors that favour or limit this coverage during the National Nutrition Weeks in Mali. DESIGN: Cross-sectional study. Interviews about demographic factors and children's adherence to the vitamin A capsule distribution programme were conducted. Professionals' knowledge of vitamin A and various aspects related to the supplementation strategy were assessed. SETTING: Five regions out of the eight regions in the country, in addition to Bamako District. Three rural communes were selected in three regions to represent rural areas. SUBJECTS: Parents or caregivers of children under 5 years of age, health agents who participated in the weeks, and community and administrative leaders. RESULTS: At least 80% of the children received the supplement. More 'traditional' communication channels (town criers, friends and family members) appeared to be more effective in reaching the target groups than modern methods, i.e. radio and television. Mothers' possession of a radio (Pearson chi2 = 5.03; P = 0.025) and fathers' education (Pearson chi2 = 19.02; P < 0.001), possession of a radio (Pearson chi2 = 8.93; P = 0.003) and listening to it (Pearson chi2 = 7.62; P = 0.006) all appeared to be statistically and significantly associated with children's coverage. In multivariate logistic regression analysis, only the study site (urban/rural) (P = 0.004), 'traditional channels' (P = 0.02) and fathers' education (P = 0.04) were significantly associated with children's coverage. Knowledge about VAS was high among community and administrative leaders, and health professionals. The planning and implementation of activities at the district level were found to be good in general. CONCLUSION: National Nutrition Weeks provide a successful example of a periodic VAS strategy with high coverage among children aged 6-59 months in Mali. Campaigns aimed at informing and sensitising populations during the Nutrition Weeks should also target children's fathers.  相似文献   
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Milicia excelsa and M. regia are important timber species in moist tropical areas of Africa. They have not been successfully grown largely because of attacks by gall-forming psyllids in the genus Phytolyma. Our objectives were to evaluate the growth of planted Milicia seedlings and incidence of psyllid attack in small (4.2 m2), medium (18.5 m2) and large (>500 m2) artificial gaps in the Bobiri Forest Reserve in the Moist Semi-Deciduous Forest of Ghana. After 13 months, height and diameter growth of Milicia seedlings were significantly greater in the medium and large gaps than in the small gaps. Insect attacks occurred first and most severely in the large gaps, but spread to gaps of all sizes between the 11th and 13th months after planting. While gap size significantly affected the susceptibility of seedlings to psyllid attack, it is not the only factor important in determining susceptibility of Milicia excelsa under field conditions. We conclude that gap sizes in the range of 10–50 m2, where irradiances are from 30–60% of full sunlight, in forests similar to those at the study site, seem to be most suitable for regeneration of Milicia.  相似文献   
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