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1.
Faecal samples were collected, as part of the National Health Surveillance Program for Cervids (HOP) in Norway, from wild red deer, roe deer, moose and reindeer during ordinary hunting seasons from 2001 to 2003. Samples from a total of 618 animals were examined for verocytotoxic E. coli (VTEC); 611 animals for Salmonella and 324 animals for Campylobacter. A total of 50 samples were cultivated from each cervid species in order to isolate the indicator bacterial species E. coli and Enterococcus faecalis/E. faecium for antibiotic resistance pattern studies. Salmonella and the potentially human pathogenic verocytotoxic E. coli were not isolated, while Campylobacter jejuni jejuni was found in one roe deer sample only. Antibiotic resistance was found in 13 (7.3%) of the 179 E. coli isolates tested, eight of these being resistant against one type of antibiotic only. The proportion of resistant E. coli isolates was higher in wild reindeer (24%) than in the other cervids (2.2%). E. faecalis or E. faecium were isolated from 19 of the samples, none of these being reindeer. All the strains isolated were resistant against one (84%) or more (16%) antibiotics. A total of 14 E. faecalis-strains were resistant to virginiamycin only. The results indicate that the cervid species studied do not constitute an important infectious reservoir for either the human pathogens or the antibiotic resistant microorganisms included in the study.  相似文献   
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Abstract

The effect of different cleaning treatments on moose (Alces alces L.) damage to Scots pines (Pinus sylvestris L.) was examined using a generalized linear mixed model (GLMM) with a binomial response (logit-link function). The treatments were the following: no cleaning, point-cleaning of broadleaves (mainly birch, Betula pendula Roth and B. pubescens Ehrh.) within a radius of 1 m from the pine, point-cleaning delayed 2 years, topping of competing broadleaves (main stem cut at a height of 1.3 m) and total cleaning of broadleaves. A randomized complete block design with three replicates was established in three planted pine stands (mean height of pines 1.5 m). Measurements taken four growing seasons later (mean height of pines 3.5 m) showed that all cleaning treatments reduced moose damage, although the difference was not significant (p=0.078) in the case of topping. The proportion of damaged pines was predicted as a function of the characteristics of pines and broadleaves in two untreated, planted pine stands with a height of 3 m. Within these untreated stands the number of damaged pines increased in plots with a higher number of broadleaves and taller broadleaves. In conclusion, the results show that on relatively fertile growing sites of pine cleaning treatments reduced moose damage on pine. It is recommended that cleaning is performed before broadleaved trees occur as overgrowth above pines.  相似文献   
3.
Aspen (Populus tremula L.) and rowan (Sorbus aucuparia L.) are important for biodiversity conservation and aesthetic reasons. Intensified levels of ungulate browsing the last decades have raised concerns over the recruitment of aspen and rowan in boreal forests. Demographic data are vital to understand and quantify how the structure of tree populations are affected over time by browsing and other factors but such data are rare. In a five-year study, we quantified vital demographic rates for co-occurring aspen and rowan using exclosures in a productive forest area in eastern-central Sweden. Mean annual browsing rate on small (<1 m) aspen and rowan stems was 20 vs. 38%, whereas the order in browsing intensity was reversed for stems of medium (1–2 m) size (28 vs. 14%). Browsing had a clear negative effect on transition rate from small to medium size class in both species, but had a much smaller impact on transition rate from medium to large (2–3 m) size class. Residence time for small stems and regeneration rate was much higher in aspen than in rowan, but browsing did not affect these dynamics. Transition to ungulate safe height (>3 m) was reduced with a factor of two in rowan and four in aspen by browsing.  相似文献   
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5.
Abstract

In Sweden, there is a longstanding conflict between the use of forests for timber production and game for hunting due to browsing damages on young forests. This study examines the assessments of two stakeholder groups regarding browsing damage by moose. The data originated from a mail survey that involved hunters and forest owners in Sweden. The samples were randomly selected from two national registers of hunters and forest owners, respectively. An ordered logit model was used to account for the assessments of severity of moose browsing damage. The results showed that on average, non-forest owning hunters rated the browsing damage on their main hunting ground lower than non-hunting forest owners rated the browsing damage on their forest estate. The respondents who both hunt and own forest had a rating that was intermediate between the former two groups. The ratings were mainly influenced by level of activity in improving game habitat, quantity of moose meat obtained, level of moose on forest estate and the importance of bagging game as well as forest estate size, hunting ground size, and the stakeholder group that the respondents belong. The findings can help in designing strategies for conflict resolution between forestry and hunting for moose.  相似文献   
6.
An appropriate moose management requires knowledge about how the economy of moose, in terms of values (benefits) and costs, responds to alterations in the moose population. This article, that is based on an empirical study, focuses on one segment of this problem field—the value of moose hunting. It deals with the question of how this value, including aspects of recreation as well as meat, is changing when the moose population density is altered. Furthermore, the article discusses the significance to the hunting value of the moose population's age structure. Generally the hunting value increases—but at a decreasing rate—as the moose population density is increased. There are, however, large geographical differences, so that a certain increase in the moose population density means a lot to the hunting value in one region but less in another. Many moose hunters would, in consideration of their own hunting pleasure, prefer an adult/calve ratio for the bag of moose that diverges considerably from what is stipulated by the authorities.  相似文献   
7.
Silvicultural cleaning is commonly carried out in young stands to control competition between conifers and deciduous tree species. However, it has been questioned whether this practice affects moose (Alces alces L.) browsing on Scots pine (Pinus sylvestris L.) with respect to damage at the stand level. In this study, moose winter browsing was examined in relation to food availability in 19 Scots pine stands divided into silviculturally cleaned and non‐cleaned blocks. Cleaning had a negative effect on moose foraging in terms of reduced density, biomass availability, and height of the deciduous tree species. The total biomass consumed by moose was significantly lower on the cleaned blocks than on the non‐cleaned ones. There were no differences between the treatments in the amounts of pine consumed and in moose damage to pines. The density or biomass available of different deciduous tree species did not explain the variation in moose browsing on pine. In conclusion, timing of silvicultural cleaning with reference to moose browsing should be taken into account. If pines are not overtopped by deciduous trees, as in the present study, silvicultural cleaning is not necessary to prevent moose damage.  相似文献   
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9.
为比较大、小兴安岭驼鹿角型的差异,统计分析了二者自然脱落的干角1 0 0 0余只,结果表明,除2杈和3杈角型基本一致外,4杈以上形状变化较大。主要表现在:大兴安岭所产驼鹿角的分杈数比小兴安岭所产驼鹿角分杈数多。大兴安岭所产驼鹿角分杈数可达9杈,而小兴安岭驼鹿角分杈数最多为6杈;大兴安岭驼鹿角4杈以上为掌状,属“掌型”,而小兴安岭驼鹿角4杈以上绝大多数为“杈型”;大小兴安岭驼鹿角各种分杈所占比例不同。大兴安岭驼鹿的4杈角最多,而小兴安岭驼鹿的3杈角最多;对于分杈数相同的驼鹿角,大兴安岭产驼鹿角的掌状面积、最大角长和重量都大于小兴安岭驼鹿角;而大兴安岭驼鹿角的角基直径却小于小兴安岭驼鹿角  相似文献   
10.
This study examines a large number of structural and growth-related responses of young Scots pine in relation to simulated browsing from large herbivores. We combined different modes of intensity, timing, and duration of clipping for nine consecutive years from 2000 to 2008. Data on tree responses were collected yearly during this period, as well as in 2011, and were analyzed using ordination techniques and generalized linear models. A key result demonstrated is the serious effects of clipping on the youngest pines. Mortality was high when clipping started the first year, indicating that the trees are vulnerable at that stage, but after that increasing intensity and duration of clipping were the main causes of mortality. Among the different treatment factors, intensity of clipping had the largest influence on altering the final growth responses, some of the quality responses, and mortality. Timing of clipping was the most important factor for explaining the occurrence of the majority of responses related to stem structure. Duration of clipping had the largest effect on the responses that included repeated-measures data, such as height development and number of stems. We discuss the long-term consequences of browsing for the trees and the implications for forest management.  相似文献   
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