排序方式: 共有27条查询结果,搜索用时 31 毫秒
1.
Baudron Frédéric Schultner Jannik Duriaux Jean-Yves Gergel Sarah E. Sunderland Terry 《Landscape Ecology》2019,34(2):341-356
Landscape Ecology - It remains unclear how agricultural landscapes can best serve multiple purposes such as simultaneously maintaining agricultural productivity and conserving biodiversity. Our... 相似文献
2.
S. A. Ward K. D. Sunderland R. J. Chambers A. F. G. Dixon 《European journal of plant pathology / European Foundation for Plant Pathology》1986,92(4):175-183
The relation between the population density of the cereal aphid,Sitobion avenae, and the proportion of wheat tillers infested is examined. Three of the six models considered require the assumption that the aphids' spatial configuration can be described by a single statistical distribution; as this is not true forS. avenae these models are unsuitable. When the other three models were applied to field sample data, only that of Nachman (1981) yielded a regression equation that remained constant throughout the development of the aphid population.Samenvatting Om in de praktijk gebruik te kunnen maken van incidentie (de fractie bezette halmen) voor het schatten van graanluispopulaties moet dezelfde relatie tussen dichtheid en incidentie tijdens het hele groeiseizoen gelden. Uit analyses van veldgegevens voor de graanluisSitobion avenae blijkt dat wel het geval te zijn, zodat bepalingen van incidentie kunnen worden gebruikt om de populatiedichtheid betrouwbaar te schatten. 相似文献
3.
Marjan Sedighi-Gilani Homeira Sunderland Parviz Navi 《Wood Science and Technology》2005,39(6):419-430
The pattern and extent of variation of microfibril angle (MFA) in normal and compression tracheids of softwood were investigated
by using confocal laser scanning microscopy technique. All measurements support the idea that the orientation of microfibrils
in single wood tracheids is not uniform. MFA of the radial wall of earlywood tracheids was highly non-uniform and had an approximately
circular form of arrangement around the bordered pits (inside the border). Between the bordered pits the measured MFAs were
less than the other parts of the tracheid. In the latewood tracheids MFA was less variable. The average orientation of simple
pits in the crossfield region was consistent with the mean MFA of the tracheids; however some of the measurements showed a
highly variable arrangement in the areas between the simple pits. In many cases the local measured MFAs of compression wood
tracheids agreed with the orientation of natural helical cavities of compression wood. Comparing the measured results in different
growth rings showed that MFAs in juvenile wood are generally larger than in perfect wood. 相似文献
4.
Research was conducted in Alutilla Valley in eastern Bangladesh to identify the nature of existing agroforestry systems and to identify potential agroforestry models that could ameliorate currently degrading forest resources Data were collected through farmer participatory research and a structured quarterly survey in two villages. Qualitative and supplementary quantitative analysis methods were used to assess the financial potential of agroforestry systems. Various patterns of agroforestry exist in the study site, but all have two common principles, namely ‘integration with agriculture’ and ‘multi-functionality’. Two agroforestry models suitable for adoption by farmers have been identified. Multi-strata agroforestry, based on a fruit and timber tree canopy with vegetables and tuber species in the understorey, can be practiced in the shifting cultivation fields near settlements. Fruit and timber tree-based conservation agroforestry is well suited to manage large-scale biologically depleted landscapes. Both systems yield early financial returns, facilitating the change from shifting cultivation to multi-strata agroforestry or fruit and tree-based conservation agroforestry. 相似文献
5.
Efficacy of tulathromycin in the treatment and prevention of natural outbreaks of bovine respiratory disease in European cattle 总被引:3,自引:0,他引:3
Godinho KS Wolf RM Sherington J Rowan TG Sunderland SJ Evans NA 《Veterinary therapeutics : research in applied veterinary medicine》2005,6(2):122-135
The efficacy of tulathromycin in the treatment (phase 1) and prevention (phase 2) of bovine respiratory disease (BRD) was evaluated on commercial farms in France, Germany, Italy, and Spain. In phase 1, commingled cattle with clinical BRD were treated with tulathromycin (n = 128) or florfenicol (n = 125) on day 0. Similar percentages of animals showed sustained clinical improvement at day 14 (tulathromycin 83.3% versus florfenicol 81.0%) and had not relapsed by day 60 (tulathromycin 63.3% versus florfenicol 58.4%). In phase 2, healthy in-contact cattle were treated with tulathromycin (n = 492), tilmicosin (n = 494), or saline (n = 265) on day 0. Significantly more (P = .0001) tulathromycin-treated cattle remained healthy to day 14 (92.4%) than tilmicosin-treated (83.7%) or saline-treated (63.7%) cattle, and this was maintained through day 60 (tulathromycin 85.4% versus tilmicosin 75.1% and saline 56.2%). Tulathromycin was highly effective in the treatment and prevention of BRD. 相似文献
6.
Evaluation of tulathromycin for the treatment of pneumonia following experimental infection of swine with Mycoplasma hyopneumoniae 总被引:3,自引:0,他引:3
McKelvie J Morgan JH Nanjiani IA Sherington J Rowan TG Sunderland SJ 《Veterinary therapeutics : research in applied veterinary medicine》2005,6(2):197-202
Tulathromycin was evaluated in the treatment of pneumonia in weaned pigs inoculated intranasally with Mycoplasma hyopneumoniae. Five days postchallenge, the pigs were randomized to treatment with a single IM administration of saline, a single IM administration of tulathromycin (2.5 mg/kg; day 0), or three IM administrations of enrofloxacin (5.0 mg/kg; days 0, 1, 2). Pigs were necropsied on day 12 or 13. Unchallenged controls remained healthy with no lung pathology. Compared with saline, coughing, mean lung lesion score, and proportional lung weight were significantly reduced and weight gain was significantly greater for tulathromycin-treated pigs (P < .05). Compared with enrofloxacin, there were no significant differences in proportional lung weight or weight gains, but coughing and lung lesion scores were greater for tulathromycin-treated pigs (P < .05). Tulathromycin was effective in the treatment of pneumonia following experimental infection with M. hyopneumoniae. 相似文献
7.
The efficacy of an injectable formulation of danofloxacin (180 mg/ml) in the treatment of naturally occurring bovine respiratory disease was evaluated in field studies on farms in France, Ireland and the United Kingdom. Cattle aged one week to 15 months with clinical respiratory disease were randomly allocated to treatment with 6 mg/kg danofloxacin or 10 mg/kg tilmicosin, administered by a single subcutaneous injection on day 0. A second injection of danofloxacin was administered on day 2, only if predefined clinical criteria were met. Mannheimia haemolytica, Pasteurella multocida and Haemophilus somnus were isolated from pretreatment nasopharyngeal swabs taken on all the farms. After the treatment, there was a more rapid improvement in the clinical response of the 178 animals treated with danofloxacin by day 2 (P < 0.01) than in the 90 treated with tilmicosin. For both treatments, there were similar significant (P < 0.001) reductions in the mean rectal temperature and severity of clinical signs of abnormal respiration and depression, on days 4 and 10 compared with day 0; 78.1 per cent of the animals treated with danofloxacin and 78.5 per cent of those treated with tilmicosin completed the studies. Danofloxacin 18 per cent was clinically safe and as effective as tilmicosin in the treatment of bovine respiratory disease. 相似文献
8.
Syed Ajijur Rahman Muhammad Hasan Imam Denyse J. Snelder Terry Sunderland 《Small-Scale Forestry》2012,11(4):529-538
In the Padma floodplain of Bangladesh, the traditional system of agriculture has become unsustainable due to high population growth. Mango-based agroforestry which has been practiced by the farmers since the 1990s, is a promising alternative and is considered as one of the few options to lift farmers out of poverty and improve livelihood security. This paper examines the potential of mango-based agroforestry to improve livelihoods, using data collected by rapid rural appraisal, farmer participatory research, stakeholder analysis and a farm household survey in six representative villages in the floodplain. Farmers with the least land were found to allocate a higher percentage of their land to agroforestry, and the increased income from agroforestry compared to other agricultural systems helps reduce relative poverty. This income maintains basic household needs, providing food security and fuelwood, and contributes to healthcare, housing and sanitation conditions, and meeting educational expenses. 相似文献
9.
藤类广泛分布于非洲大陆热带森林的低地上,对区域林业经济发挥着重要作用。在非洲分布的20种之中有6种已被用于商业资源开发。尽管非洲藤类的经济价值很高,但至今对它们的分类仍不太确定。本文描述了单苞藤属和肿胀藤属的2个新种,分别从分类学、形态学、特征、生物学特性、保护和利用等方面做了研究。 相似文献
10.
Rooney KA Illyes EF Sunderland SJ Sarasola P Hendrickx MO Keller DS Meinert TR Logan NB Weatherley AJ Conder GA 《American journal of veterinary research》1999,60(4):402-404
OBJECTIVE: To determine effectiveness of a pour-on formulation of doramectin against Damalinia bovis, Haematopinus eurysternus, Linognathus vituli, Solenopotes capillatus, Chorioptes bovis, Sarcoptes scabiei, Hypoderma bovis, and Hypoderma lineatum. ANIMALS: Cattle of various ages with naturally acquired or artificial infestations with 1 or more species of lice, mites, or grubs. PROCEDURE: In 10 louse and 6 mite studies, cattle were treated with doramectin (500 microg/kg, topically) on day 0, and parasite counts were performed approximately weekly from days 0 to 35. In 6 grub studies, cattle expected to harbor Hypoderma spp were treated before emergence of warbles. After warbles began to emerge, they were counted every 2 weeks, and grubs were collected and identified by species. RESULTS: Burdens of D bovis, H eurystemus, L vituli, and S capillatus on doramectin-treated cattle were 0 by 28 days after treatment. Burdens of C bovis and S scabiei decreased to 0 in naturally infested cattle and approximately 0 in artificially infested cattle by day 14 to 15. In grub studies, 107 of 136 control cattle had warbles, whereas 2 of 136 doramectin-treated cattle had 1 warble each, which represented a cure rate of 98.5%. CONCLUSION AND CLINICAL RELEVANCE: One topical application of doramectin was highly efficacious against common species of lice, mites, and grubs known to affect performance, health, and appearance of cattle. 相似文献