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991.
An 8‐year‐old Appaloosa mare with rectal paralysis due to a cosmetic ethanol ‘tail block’ was treated with traditional Chinese veterinary medicine treatments including acupuncture and herbal medicine. Her rectal and tail tone gradually improved after the treatment. At 4 months after initial presentation, the mare was able to produce faecal piles on a regular basis, and manual evacuations were no longer needed. Significant improvement was within 30 days of beginning treatment. At 8 months, the owner indicated that the mare had normal defaecation, was able to swish the tail from side to side and lift the tail to urinate, and had no evidence of straining to defaecate or colic.  相似文献   
992.
西藏部分地区藏猪戊型肝炎病毒血清流行病学调查   总被引:1,自引:0,他引:1  
为了解西藏地区藏猪戊型肝炎流行情况,在拉萨、林芝、昌都、日喀则和山南等5个市,采集305份藏猪血清,利用酶联免疫吸附(ELISA)法进行戊型肝炎病毒血清抗体检测,并用SPSS 21.0方法进行不同性别、不同区域间的显著性差异分析。结果显示:从305份藏猪血清中检测到81份抗体阳性,总抗体阳性率为26.6%(81/305);拉萨市和林芝市的抗体阳性率最高,达32.8%(20/61),其次为昌都市、日喀则市和山南市,阳性率分别为29.5%(18/61)、26.2%(16/61)、11.5%(7/61);山南市阳性率与其他4个市相比差异显著(P0.05),公猪和母猪的抗体阳性率分别为23.3%(35/150)和29.7%(46/155),无显著差异(P0.05)。结果表明,西藏地区藏猪群中存在不同程度的猪戊型肝炎病毒感染。鉴于当地存在食用生或半生猪肉和猪肝的习俗,建议加强宣传,倡导健康饮食,同时加强高发区疫病防治,降低人类感染风险。  相似文献   
993.
Pepper huasteco yellow vein virus (PHYVV) is the main virus of pepper crop in Mexico. No resistant cultivars are available and resistance breeding is hampered by the lack of knowledge of heritability (h 2) of PHYVV resistance. This is a continuation of previous studies and the objectives were to analyze the h 2 and the behavior of the resistant trait to PHYVV. Four resistant assays were done with three resistant wild lines (UAS12, UAS13 and UAS10) of Capsicum annuum in the S4, S5, S6 and S7 generation under greenhouse conditions. Plants from all tests were inoculated with PHYVV through Bemisia tabaci. Line UAS12 was the most resistant showing a significantly proportion of resistant plants, less disease symptoms and longer incubation time, followed by the lines UAS13 and UAS10 in all assays. Distribution of symptoms showed a bimodal tendency in all the trials, suggesting that two groups of genes are involved in this resistance trait. The lines UAS12, UAS13 and UAS10 showed the same pattern of response to selection with an average of h 2 of 0.17, 0.06, 0.02 and 0.00 in the S4, S5, S6 and S7, respectively. These results indicate that all lines responded positively to the selection in the S4, S5 and S6, whereas in the S7 there was no response by the possible exhaustion of variation. Line UAS12 is the most promising genotype and the lines UAS13 and UAS10 are genetic resources that can be supplemented to breed the resistance of PHYVV. These results provides basic information for resistance breeding.  相似文献   
994.
Translocations of the short arm of rye (Secale cereale L.) chromosome 1 (1RS) in wheat (Triticum aestivum L. cv. Pavon 76) are known to increase root biomass. Such an increase enhances water and nutrient uptake and may improve grain yield. Two greenhouse experiments and a field experiment were carried out at the University of California, Riverside, in 2012 and 2013 under well‐watered and terminal drought treatments to evaluate phenotypic characters associated with varying dosages of 1RS, including grain yield. The genotypes used were cultivar Pavon 76 (R0), Pavon 76/Pavon1RS.1AL (F1 hybrid) with a single dosage of 1RS (R1A), Pavon 1RS.1AL with two dosages of 1RS (R2A), Pavon 1RS.1DL (R2D) also with two dosages of 1RS and Pavon 1RS.1AL‐1RS.1DL (R4AD) with four dosages of 1RS. There was a significant positive correlation between number of dosages of 1RS and root biomass. However, no correlation was found between root biomass and grain yield per plant. Drought in the field experiment reduced grain yield significantly. Under well‐watered field conditions, grain yield of R2A (215.9 g plant?1) was significantly greater than those of R2D (191.8 g plant?1) and R4AD (161.7 g plant?1). Also, grain yield of R4AD was significantly less than those of F1, Pavon 76 and R2D under well‐watered conditions. Under drought field conditions, no significant differences were found among the genotypes for grain yield was found between F1 (14.7 g plant?1) and R4AD (12.4 g plant?1). Harvest index was significantly greater in well‐watered (44.2 %) than in drought (34.6 %) field conditions. On average, genotypes F1 (42.3 %) and R2A (40.6 %) had higher harvest index than R2D (38.3 %) and R4AD (35.5 %) in the field. Also, Pavon 76 (40.2) and R2D (38.3) had higher harvest index than R4AD. Drought tolerance was lowest for R4AD due to its relatively lower grain yield potential. In general, Pavon 1RS.1AL carrying two dosages of 1RS showed higher grain yield under wet treatments. Pavon 1RS.1AL‐1RS.1DL carrying four dosages of 1RS produced the largest shoot and root biomasses, but the least grain yield.  相似文献   
995.

Context

Species distributions are driven by a wide variety of abiotic and biotic factors, including nest placement for breeding individuals. As such, the spatial distribution of nests within a landscape can reflect environmental heterogeneity, habitat preferences, or even interactions with predators and other species.

Objectives

We determined the extent to which environmental heterogeneity and predation risk accounted for the observed spatial distribution of nests.

Methods

We assessed the spatial distribution of 112 nests of a migratory shorebird, the Hudsonian Godwit (Limosa haemastica), at Beluga River, Alaska, from 2009 to 2012, and explicitly tested for the relative influence of habitat characteristics and predation risk on nest locations. We also evaluated the effect of nest location, distance to conspecific nests, and proximity to roads on nest fate using 64 nests that were monitored through completion.

Results

Hudsonian Godwit nests were clustered across the landscape despite a lack of significant spatial autocorrelation (i.e., patchiness) in vegetation characteristics at either the micro- or landscape scale. Nest fate also was not predicted by either the distance to the nearest conspecific neighbor or proximity to roads. Thus, neither habitat characteristics nor predation risk explained the clustering of godwit nests.

Conclusions

These results suggest that godwits may select nest locations based more on social cues than underlying heterogeneity in vegetation or predation risk. As such, intra- and inter-specific interactions should be considered when developing management plans for species of conservation concern.
  相似文献   
996.

Context

The assessment of land-use impacts on biodiversity is one of the central themes of landscape ecology and conservation biology. However, due to the complexity of biodiversity, it is impossible to obtain complete information about the diversity of all species even for small areas, necessitating the selection of individual species or assemblages thereof as species surrogate. In parts of the world where taxonomic expertise is lacking, species identification has hindered progress in biodiversity conservation, and the only practical, relatively-accurate option, is the use of taxonomic minimalism.

Objective

We carried out a rapid biodiversity assessment based on three surrogates—land-use (driver-surrogate), terrestrial arthropods (species-surrogate) and morphospecies (taxonomic-surrogate)—to determine the impacts of land-use on biodiversity of the Western Region (Ghana), an area covering ~4 % of the West African biodiversity hotspot.

Method

We used diversity profiles to visualize the distribution of a total of 8848 arthropod individuals over seven land-use types which define the complete heterogeneity of the landscape.

Results

Here, we present both sample and asymptotic diversity profiles of arthropod morphospecies for each land-use type and the potential of each land-use type for conserving arthropods.

Conclusions

We conclude that (1) the morphospecies approach is useful for detecting differences in species diversity of land-use types; (2) the concept of asymptotic diversity may not be necessary for land-use based biodiversity comparison; and (3) maximum diversity profiles are useful for determining the land-use conservation values in cases where pristine areas are not available.
  相似文献   
997.
998.

Context

Playa wetlands are the primary habitat for numerous wetland-dependent species in the Southern Great Plains of North America. Plant and wildlife populations that inhabit these wetlands are reciprocally linked through the dispersal of individuals, propagules and ultimately genes among local populations.

Objective

To develop and implement a framework using network models for conceptualizing, representing and analyzing potential biological flows among 48,981 spatially discrete playa wetlands in the Southern Great Plains.

Methods

We examined changes in connectivity patterns and assessed the relative importance of wetlands to maintaining these patterns by targeting wetlands for removal based on network centrality metrics weighted by estimates of habitat quality and probability of inundation.

Results

We identified several distinct, broad-scale sub networks and phase transitions among playa wetlands in the Southern Plains. In particular, for organisms that can disperse >2 km a dense and expansive wetland sub network emerges in the Southern High Plains. This network was characterized by localized, densely connected wetland clusters at link distances (h) >2 km but <5 km and was most sensitive to changes in wetland availability (p) and configuration when h = 4 km, and p = 0.2–0.4. It transitioned to a single, large connected wetland system at broader spatial scales even when the proportion of inundated wetland was relatively low (p = 0.2).

Conclusions

Our findings suggest that redundancy in the potential for broad and fine-scale movements insulates this system from damage and facilitates system-wide connectivity among populations with different dispersal capacities.
  相似文献   
999.
1000.

Context

Common indicators are needed to monitor biodiversity loss and the implications for the sustainable provision of ecosystem services (ES). A plethora of different sets of indicators may hinder the identification of major endpoints for large-scale assessments of biodiversity and ecosystem services (BES).

Objectives

We aim to describe the main challenges of indicators for BES assessment and provide suggestions for establishing a comprehensive indicator system.

Methods

An extensive literature review was conducted in this study. We review the main challenges of indicators for BES assessment and propose corresponding improvements from our perspectives of theory and practical applications.

Results

The main theoretical challenges of existing indicators include inconsistent definitions and classifications of ES, misunderstanding of linkages among biodiversity, ecosystem structure, functions and services, and practical problems relate to such issues as indicator representativeness, data availability, and uncertainty. Our suggested improvements include clarifying the main terms, concepts and classification of indicators, establishing a robust conceptual framework with clear interactions among different components and indicators, selecting indicators based on ecosystem properties, streaming existing data into one platform, and strengthening validation of proxies. The steps for constructing a comprehensive indicator system for BES assessment are summarized.

Conclusions

Clear definitions of key terms are indispensable to classify indicators and construct a conceptual framework. Improved understanding of the relations among indicators of biodiversity, ecosystem functions, and ES across multiple scales can guide the development of the indicator system. The integrated indicator system is an important tool for BES assessment to support decision making for sustainable development.
  相似文献   
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