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1.
Gough JF 《The Canadian veterinary journal. La revue veterinaire canadienne》1989,30(8):672-674
Outbreaks of budgerigar fledgling disease (BFD) occurred in three budgerigar aviaries in Ontario. Acute death in seven to ten-day-old nestlings and feather abnormalities in birds over three weeks of age were common findings. Ascites, hepatomegaly and hydropericardium were prominent gross lesions. Histologically, basophilic intranuclear inclusions were seen in many tissues. A severe drop in hatchability occurred in one aviary—a finding not previously reported with BFD. Interruption of breeding controlled the disease in aviary 1, but failed in two consecutive attempts in aviary 2. A third outbreak occurred in aviary 2 after depopulation and restocking. In aviary 3, the spread of disease was very rapid; 90% of the nestlings died within a few weeks. A papovavirus similar to a previously described isolate was recovered in this outbreak. 相似文献
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Gough D 《Science (New York, N.Y.)》2001,291(5512):2325-2327
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This article analyzes the relationship between forest resources, refugees, and the host population. The findings of the research
suggest that the host population are heavily dependent on the local forest for their daily needs such as fuelwood, timber,
grazing area, fodder for domestic animals, foods, and medicine in addition to cultural and esthetic needs. The forest has
also been relied upon for agricultural needs such as manufacture of agricultural tools, maintenance of irrigation water systems,
erosion control, and fertilizer needs. The forest was under a sustained demand as any other Terai forest of Nepal. After the
arrival of refugees in 1992, the demand for forest resources increased substantially. Initially, the construction of the refugee
camps decreased the total forest area and also required some felling of trees. More significantly, the refugees themselves
became active users of the forest resource, which generated extra pressure on the forest and created scarcity of forest resources.
Before the arrival of the refugees, forest management and monitoring of illegal use of the forest resources were carried out
by the government through its local forester office. The local residents were active users of the forest resources, but were
passive in managing and maintaining the forest resource. However, competition from the refugees instilled a desire in the
local population to safeguard and protect the dwindling resource against the external threat by creating the Humse Dumse Community
Forest. 相似文献