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81.
野猪对农作物的危害是当前人与野生动物冲突的典型案例,分析其危害特征,掌握当地居民对野猪危害与保护管理的态度,对于自然保护区社区共管与野生动物保护管理决策尤为重要。对贵州赤水桫椤国家级自然保护区的调查研究发现,野猪一年四季均危害农作物,危害高峰期在 2-4 月与10-12 月,主要受作物收获期影响;农耕地在保护区的位置、距道路距离及距水源距离显著影响野猪对农耕地的危害,农耕地距道路(< 55 m)和水源越近(< 270 m),遭受危害程度越高。保护区的实验区和周边区域人居活动强烈,但野猪危害较其他区域严重,野猪危害农地时对水源因素较距居民点距离、距林缘距离、隐蔽因素更为敏感。70% 的当地居民认为野猪危害是由于种群数量过多引起。55% 的当地居民不赞同国家保护野猪的政策,62% 的赞同猎杀野猪控制其种群数量增长。受访者年龄与野猪危害程度两因素显著影响居民对野猪的容忍度,50 - 70 岁是当地社区居民的主要人群,也是态度中立及容忍度较高的人群。为有效减少野猪危害损失,调和人与野生动物冲突矛盾,建议保护区管理者根据野猪危害特征,帮助当地居民建立有效防控措施和有效快速的危害评估与损失补偿机制,同时根据当地居民的态度特征,做好保护政策的宣教工作。  相似文献   
82.
人工繁育是濒危物种保护的重要手段,但是也会改变物种的表型。为了探究人工繁育对于鳄蜥(Shinisaurus crocodilurus)形态和健康状况的影响,本研究比较了人工繁育鳄蜥与野外鳄蜥新生幼体及亚成体形态特征与细菌感染率。结果发现,人工繁育鳄蜥与野外鳄蜥的新生幼体体型无显著差异,而人工繁育鳄蜥亚成体体型显著大于野外鳄蜥;两个年龄段的人工繁育鳄蜥断尾率均显著低于野外鳄蜥;人工繁育鳄蜥亚成体细菌感染率最高,但是各年龄组种群间的差异不显著。本研究表明,人工环境促进了鳄蜥的生长,减少了鳄蜥被捕食的风险,但有增加鳄蜥感染疾病的可能性,因此在鳄蜥的饲养管理中需要加强疾病防治。  相似文献   
83.
With the aim to select new olive cultivars with superior physical and chemical properties than the cultivar Chemlali Sfax, the present study focused on the comparison of the chemical composition and the sensory profile of the virgin olive oils (VOOs) of two wild olive trees (Oleasters K and M) with those of VOOs obtained from Chemlali Sfax and Neb Jmel olive cultivars, all growing in the coastal region of Tunisia. Despite the variability in the chemical composition (fatty acids, pigments, and phenolic and volatile compounds) and the organoleptic profile of the VOOs of the oleasters and the cultivars, the quality indices (free fatty acids, peroxide value, and spectrophotometric indices K232 and K270) as well as the fatty acid composition of all VOOs studied met the commercial standards. Both the α-tocopherol and phenol contents varied between the genotypes. The Neb Jmel and Oleaster K VOOs had more than two times higher total phenol levels than the Chemlali Sfax and Oleaster M VOOs. Also the contents of volatile compounds differed between the olive oils studied. Chemlali Sfax and Oleaster K oils were more abundant in aldehydes, whereas Oleaster M VOO had higher contents of alcohols. These results were confirmed by a sensorial analysis showing that the later oil was deprived for consumption despite its abundance in α-tocopherol. In conclusion, the oleasters studied revealed to be interesting, since they produced oils with good quality characteristics in terms of minor compounds (phenols and volatiles) compared to the Chemlali Sfax cultivar.  相似文献   
84.
The ingestion of undercooked meat from wild animals can be a source of Toxoplasma gondii infection in humans and other animals. In this study, we determined the seroprevalence of T. gondii infection in 175 wild boars (Sus scrofa leucomystax) and 107 wild sika deer (Cervus nippon) hunted in 2004–2007 in Gunma Prefecture, Japan, by using a commercial latex agglutination test (LAT). Antibodies (LAT, 1:64 or higher) to T. gondii were found in 6.3% of wild boars and 1.9% of sika deer. This is the first record of T. gondii infection in wild deer in Japan, and deer and wild boar meat should be cooked well before human consumption.  相似文献   
85.
The use of an anti-gonadotropin-releasing hormone vaccine for immunocastration of male pigs has been recently approved in the European Union. This technique is potentially useful for avoiding both castration-associated pain for the animal and boar taint in pork. However, some animals may escape immunocastration and be slaughtered as entire males, potentially exhibiting boar taint. Therefore, it is important to check the efficacy of immunocastration on the slaughter line. To achieve that, the currently proposed method, based on testis weight, is not fully reliable because there is some overlap in the distributions of testis weight between immunocastrates and entire males. On the basis of literature data on the effect of immunocastration on the development of accessory sex glands, this paper provides evidence that the weight of seminal vesicles might be a much better criterion for checking the efficacy of immunocastration, because their size decreases more rapidly, and to a greater extent, than that of the testis.  相似文献   
86.
Trichinellosis is one of the most serious foodborne parasitic zoonoses in Europe. Wild carnivorous and omnivorous hosts are the main reservoirs of Trichinella spp. nematodes in nature. In the winter of 2008-2009, an atypical clinical case of trichinellosis occurred for the consumption of pork from a wild boar (Sus scrofa) hunted in southwestern Alps in Italy. The symptomatic individual showed delayed development of oedemas in the lower limbs and eosinophilia, which appeared three months after infection. Muscle samples harboured 3.8 larvae/g, which were identified as Trichinella britovi. During the epidemiological investigation, anti-Trichinella IgG were detected in five hunters.  相似文献   
87.
A total of 111 rhizobial strains were isolated from wild legumes in Xinjiang, an isolated region of northwest China. Nine genomic species belonging to four genera of Rhizobium, Mesorhizobium, Ensifer, and Bradyrhizobium were defined among these strains based on the characterization of amplified 16S ribosomal DNA restriction analysis (ARDRA), restriction fragment length polymorphism (RFLP) analysis of 16S-23S rDNA intergenic spacers (IGS), 16S rRNA gene sequencing and multilocus sequence analysis (MLSA). Twenty-five nodC types corresponding to eight phylogenetic clades were divided by RFLP and sequence analysis of the PCR-amplified nodC gene. The acid-producing Rhizobium and Mesorhizobium species were predominant, which may be related to both the local environments and the hosts sampled. The present study also showed the limitation of using nod genes to estimate the host specificity of rhizobia.  相似文献   
88.
Yield-enhancing quantitative trait loci (QTLs) from wild species   总被引:1,自引:0,他引:1  
Wild species of crop plants are increasingly being used to improve various agronomic traits including yield in cultivars. Dense molecular maps have enabled mapping of quantitative trait loci (QTLs) for complex traits such as yield. QTLs for increased yield have been identified from wild relatives of several crop plants. Advanced backcross QTL analysis has been used to identify naturally occurring favorable QTL alleles for yield and minimize the effect of unwanted alleles from wild species. Yield QTLs from wild species are distributed on almost all chromosomes but more often in some regions. Many QTLs for yield and related traits derived from different wild accessions or species map to identical chromosomal regions. QTLs for highly correlated yield associated traits are also often co-located implying linkage or pleiotropic effects. Many QTLs have been detected in more than one environment and in more than one genetic background. The overall direction of effect of some QTLs however, may vary with genetic context. Thus, there is evidence of stable and consistent major effect yield-enhancing QTLs derived from wild species in several crops. Such QTLs are good targets for use in marker assisted selection though their context-dependency is a major constraint. Literature on yield QTLs mapped from wild species is summarized with special reference to rice and tomato.  相似文献   
89.
Full analysis of eight seed samples collected in the 1960's excavations at Neolithic Çatalhöyük East, Turkey, is presented. Detailed investigation of the composition and context of the samples suggests that the Neolithic population collected, processed and stored seeds from Capsella sp. and Descurainia sp. (wild crucifers) for food use. In addition seeds of Vicia/Lathyrus sp. (wild vetch), Helianthemum spp. and Taeniatherum caput-medusae mixed with Eremopyrum type (grasses) were also found, some of which may have been used for food or other purposes. The analysis demonstrates that wild seed exploitation was a regular part of subsistence practice alongside the economic staple of crop production, and again demonstrates how diverse plant use practices were at the site.  相似文献   
90.
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