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In the present paper a review of the genus Macrocheilus HOPE, 1838 (Coleoptera: Carabidae: Helluonini) of China is provided, with descriptions of seven new species, viz. M. parvimaculatus sp. nov., M. gigas sp. nov., M. fuscipennis sp. nov., M. solidipalpis sp. nov., M. cheni sp. nov., M. quadratus sp. nov., and M. sinuatilabris sp. nov.. A key to all species found in China is also given. In addition, M. asteriscus White is reported from Laos, Indonesia and India for the first time.
Porcine parvovirus (PPV) is considered one of the most important infectious agents of reproductive failure in sows. Little information, however, is available on its prevalence in healthy fattening pigs. Therefore, in the present study, 197 fecal swabs, 197 nasal swabs, 389 serum samples, and 310 lung samples were collected from pigs aged 10-25 weeks across Hunan, China, and tested for the presence of PPV. PPV DNA was amplified by polymerase chain reaction, demonstrating an overall positivity rate of 7.69%, with a particularly high infection rate of 22.90% in the lungs. A total of five PPV strains (PPV-HuN1-5) were isolated on the basis of cytopathic effects in swine testicular cells, and the near-complete genomes were sequenced and subjected to phylogenetic analysis with reference to reported PPV sequences in GenBank. The five Hunan isolates showed a close relationship with each other and predominantly with reported European PPV strains. Moreover, seven amino acid substitutions were detected within the coding region of the VP2 of PPV-HuNs when compared with that of the Chinese vaccine strain PPV-NJ. The relatively high prevalence of PPV discovered in healthy fattening pigs despite a long-term vaccination program in China, highlights the need for improved prevention, monitoring, and control of related diseases in herds.
Discovering how to best protect one of the most endangered animals in the world, giant pandas, has always been an important project in ecological studies. Moreover, researching the living environments of giant pandas and how to recover them is one of the most important elements to these studies. In order to more effectively protect the giant pandas and their habitats, we studied the changing of Xiaohegou nature reserve landscape for 20 years, from 1994 to 2014, based on the landscape ecology theory and “3S” techniques (geographic information systems, GIS; remote sensing, RS; global navigation satellite system, GNSS). Specifically, this paper analyzes factors such as landscape fragmentation, connectivity, disturbance degree, landscape diversity, etc. Accordingly, the research presented divides giant panda habitat into nine landscape types that include: evergreen deciduous broad-leaved mixed forest, secondary broadleaved forest, mixed coniferous and deciduous broad-leaved forests, and coniferous forest, et al. The results show that: 1) before establishing the Xiaohegou Nature Reserve in 1993, deforestation was a serious problem, as the results from the 1994 landscape fragmentation suggest. 2) Logging was rampant before the implementation of the national natural forest protection project that began in 1998. Severe damage was observed on the coniferous forest in giant panda habitat. Yet, from the high level of fragmentation that was observed in the connectivity of giant panda habitat, the results suggest 1994 was the worst. After more than ten years of recovery, from 2001 to 2014, the situation of regarding the habitat’s connectivity appears better than previous years. 3) The habitat has been impacted heavily by human disturbance from 1994 to 2001, although it has shown a slight decrease in this tendency from 2001 to 2014. 4) In the past 20 years, both the diversity and evenness indexes are showing a slow drop tendency. 5) This paper analyzes the changing situation regarding the land category evolution of giant panda habitats. Coniferous forests, the main habitat of giant pandas, decreased 6.37 hm² during these 5 years, with a rate of decrease at 1.27 hm² per annum from 1994 to 1998. In the years that followed, however, the coniferous forest recovered 4.21 hm² over the course of 15 years at the rate of 0.28 hm² per annum from 1999 to 2014, providing a reference for further nature reserve policy development.
The purpose of this study was to analyze the correlation of the rate of Mycoplasma hyopneumoniae (M. hyo) in slaughter pigs with season, climate change and enzootic pneumonia (EP) lesions. We collected 530 slaughter pig lungs with suspected lesions from two slaughterhouses in different seasons and weather conditions from November 2014 to March 2017 in Changsha Hunan Province, China. The EP lesions of these lungs were quantified, and a PCR analysis was used to detect M. hyo in samples of bronchoalveolar lavage fluid (BALF). Twenty percent, 10%, and 9% of the lung specimens were scored 1-5, 6-10, and ≥ 11, respectively. Additionally, we found that 36% of all BALF samples tested positive for M. hyo. Among the lung specimens collected in winter, 41% scored 1 or more, and 53% tested positive for M. hyo. With respect to seasons, the lung specimens collected in summer showed the least number of EP lesions and the lowest positive testing rate for M. hyo. Of these specimens, 27% scored 1 or more, and 22% tested positive for M. hyo. Additionally, low temperature and fast temperature change (during 10 days before sampling) were associated with a higher rate of M. hyo detection in BALF. There was a positive correlation between the lung EP lesion score and the detection rate of M. hyo in the BALF of slaughter pigs. In conclusion, lung EP lesion scoring in slaughter pigs is of referential value to the evaluation of the dynamics of M. hyo infection in a swine population. It is essential to control the spread of M. hyo by careful management of swine populations, and the prevention and control of M. hyo in fattening pigs is of great significance to the eradication of the disease.
Potassium (K), one of main essential macronutrient elements in soil, is vital to the growth and metabolism of giant pandas (Ailuropoda melanoleuca) and its staple food bamboos (SFB). However, it is still unknown how the content of K in soil shapes giant panda distribution. To address this problem, we use geographical information system (GIS) and regression analysis to measure their spatial distribution data and analyze their relationships. Our results show a unimodal relationship between the species richness of SFB and K (R²= 0.90, P<0.01), a significant positive linear correlation relationship between SFB and giant panda (R²= 0.47, P<0.01), and a significant unimodal relationship between the K and giant panda (R²= 0.58, P<0.01). Moreover, results reveal that the giant panda may tend to select habitats with K in the soil ranging from 2.58 to 3.14 (mg/g). Our study also highlights the important effect of the eco-geological environment in shaping the distribution of giant panda. Our study suggests that it is essential to incorporate the beneficial and harmful element factors of an eco-geological environment into wildlife habitat research and management. It should improve on habitat estimation, corridor establishment, and biodiversity conservation.
We investigated the effects of nutrient levels on the abundance and diversity of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB), seven surface sediment samples from small reservoirs at different nutrient levels were collected from the eastern, central, and western parts of Huashan watershed in Chuzhou, Anhui Province to determine the abundance and community composition of AOA and AOB. The results showed that the abundance of bacterial amoA gene (1.85×107 to 2.86×108 g/dry sediment) was higher than that of archaeal amoA gene (1.25×105 to 1.23×106 g/dry sediment) in all sediment samples. The abundance of the archaeal amoA gene exhibited significant positive correlations with total nitrogen concentrations, whereas the abundance of bacterial amoA gene showed significantly negative correlation with pH. Archaeal amoA gene sequences included Nitrososphaera and Nitrosopumilus clusters and the majority of Nitrosospira and Nitrosomonas oligotropha lineages.
Duck Tembusu virus (DTMUV) is a newly emerging pathogenic flavivirus that has caused massive economic losses to the duck industry in China. Envelope (E) protein of DTMUV is an important structural protein, which is able to induce protective immune response in target animals and can be used as specific serological diagnosis tool. In this study, a novel monoclonal antibody, designated mAb 3E9, was generated against DTMUV E protein. It is positive in indirect ELISA against both His-E protein and the purified whole viral antigen. Also, this mAb showed positive reaction with DTMUV in Western blot and indirect immunofluorescence assay, and the isotype was IgG1. End-point neutralizing assay performed in BHK-21 cells revealed that the neutralization titer of 3E9 against DTMUV JS804 strain reached 1:50. Furthermore, functional studies revealed that 3E9 blocks infection of DTMUV at a step on viral attachment. The anti-E mAbs produced in the present work may be valuable in developing an antigen-capture ELISA test for antigen detection or a competitive ELISA test for antibody detection or therapeutic medicine for DTMUV in poultry.
Pasteurella multocida (P. multocida), an opportunistic zoonotic pathogen associated with high morbidity and mortality in livestock, shows significant temporal and geographical variation in its serotype distributions and phenotypic characteristics. The aim of this study was To investigate capsular types, lipopolysaccharide (LPS) genotypes, and virulence-associated genes of P. multocida strains isolated from pigs. A total of 801 samples (lungs, tonsils, nasal swabs) were collected from slaughterhouses and various regions of the Hunan province. P. multocida strains were isolated from various samples, classified, and virulence-associated genes were detected by polymerase chain reaction (PCR). 124 P. multocida strains were assigned to six groups based on both capsular type and LPS genotype, namely A: L3 (capsular type A and LPS genotype 3, 64/124); A: L6 (16/124); D: L6 (38/124); F: L3 (4/124); L3 (1/124) and 1 untypable strain. Of the 23 virulence-associated genes investigated in this study, 14 were highly expressed in 98% to 100% of the 124 strains. While tbpA was undetectable in any of the isolated strains, hsf-1, pfhA, tadD, toxA, pmHAS, hgbA, hgbB, and nanB showed differential distribution among the strain groups. Interestingly, pfhA (Mutation or inactivation of pfhA was reported to decrease the virulence of P. multocida) was found in 46% of group A: L3 strains and in 100% of group F: L3 strains, but not found in other groups. Further investigation is needed to determine whether strains in group A: L3show greater virulence than the A: L6 P. multocida strains.
Lakes are one of the most important wetland types on the earth with many ecosystem functions. With continuing economic growth and climate change, lake abundance and surface areas throughout the world have been threatened by many factors, including by human and environmental disruptions. However, we still have limited knowledge on how human activities and climate change affect lake reductions and associated ecosystem services. Elucidating the underlying mechanisms of lake shrinkage will help maintain an ecological balance in urban planning, especially in rapidly developing countries. We explore the determinants of lake shrinkage and abundance reduction from the 1980s to the 2010s using remote sensing data of lakes in two large cities in eastern China: Nanchang and Shanghai. In order to account for the non-independence of time-series data, time series auto-regressive generalized least squares (GLS) models were used to examine the relationship between lake area/abundance and human activities and climate change. Our results show that human activities rather than climate change, are the most important determinants for the areas and numbers of lake shrinkage, and gross domestic product (GDP) and population size could explain more than half of the variation in the number and area of lakes with areas larger than 20 ha in the two cities. GDP and lake area shrinkage do not exhibit a linear relationship. This highlights the importance of wetland protection in the early development stage. Because the main determinants are human activities, cities have the ability to protect wetlands via suitable planning.
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