Search

Abstract Background Feed accounts for about 70% of the total cost of poultry meat production. Residual feed intake (RFI) has become the preferred measure of feed efficiency because it is phenotypically independent of growth rate and body weight. In this study, our aim was to estimate genetic parameters and identify quantitative trait loci (QTL) for feed efficiency in 3314 purebred broilers using a genome-wide association study. Broilers were genotyped using a custom 55 K single nucleotide polymorphism (SNP) array. Results Estimates of genomic heritability for seven growth and feed efficiency traits, including body weight at 28 days of age (BW28), BW42, average daily feed intake (ADFI), RFI, and RFI adjusted for weight of abdominal fat (RFIa), ranged from 0.12 to 0.26. Eleven genome-wide significant SNPs and 15 suggestively significant SNPs were detected, of which 19 clustered around two genomic regions. A region on chromosome 16 (2.34–2.66 Mb) was associated with both BW28 and BW42, and the most significant SNP in this region, AX_101003762, accounted for 7.6% of the genetic variance of BW28. The other region, on chromosome 1 (91.27–92.43 Mb) was associated with RFI and ADFI, and contains the NSUN3 and EPHA6 as candidate genes. The most significant SNP in this region, AX_172588157, accounted for 4.4% of the genetic variance of RFI. In addition, a genomic region containing the gene AGK on chromosome 1 was found to be associated with RFIa. The NSUN3 and AGK genes were found to be differentially expressed in breast muscle, thigh muscle, and abdominal fat between male broilers with high and low RFI. Conclusions We identified QTL regions for BW28 and BW42 (spanning 0.32 Mb) and RFI (spanning 1.16 Mb). The NSUN3, EPHA6, and AGK were identified as the most likely candidate genes for these QTL. These genes are involved in mitochondrial function and behavioral regulation. These results contribute to the identification of candidate genes and variants for growth and feed efficiency in poultry.

Abstract Background Edwardsiella tarda causes acute symptoms with ascites in Japanese flounder (Paralichthys olivaceus) and is a major problem for China’s aquaculture sector. Genomic selection (GS) has been widely adopted in breeding industries because it shortens generation intervals and results in the selection of individuals that have great breeding potential with high accuracy. Based on an artificial challenge test and re-sequenced data of 1099 flounders, the aims of this study were to estimate the genetic parameters of resistance to E. tarda in Japanese flounder and to evaluate the accuracy of single-step GBLUP (ssGBLUP), weighted ssGBLUP (WssGBLUP), and BayesB for improving resistance to E. tarda by using three subsets of pre-selected single nucleotide polymorphisms (SNPs). In addition, SNPs that are associated with this trait were identified using a single-SNP genome-wide association study (GWAS) and WssGBLUP. Results We estimated a heritability of 0.13 ± 0.02 for resistance to E. tarda in Japanese flounder. One million SNPs at fixed intervals were selected from 4,978,724 SNPs that passed quality controls. GWAS identified significant SNPs on chromosomes 14 and 24. WssGBLUP revealed that the putative quantitative trait loci on chromosomes 1 and 14 contained SNPs that explained more than 1% of the genetic variance. Three 50 k-SNP subsets were pre-selected based on different criteria. Compared with pedigree-based prediction (ABLUP), the three genomic methods evaluated resulted in at least 7.7% greater accuracy of predictions. The accuracy of these genomic prediction methods was almost unchanged when pre-selected trait-related SNPs were used for prediction. Conclusions Resistance to E. tarda in Japanese flounder has a low heritability. GWAS and WssGBLUP revealed that the genetic architecture of this trait is polygenic. Genomic prediction of breeding values performed better than ABLUP. It is feasible to implement genomic selection to increase resistance to E. tarda in Japanese flounder with 50 k SNPs. Based on the criteria used here, pre-selection of SNPs was not beneficial and other criteria for pre-selection should be considered.

Hypertension is the most common chronic disease in the Chinese population. The study analyzes the differences of hypertension in different regions in China from space, analyzes the influencing factors of the disease, and the spatial distribution of different populations. The data comes from CHARLS Harmonize. 22,310 interviewees were selected to respond effectively. Single-factor chi-square test and binary logistic regression were used to analyze the factors affecting hypertension. BMI, urban and rural areas, jogging 1KM, smoking, drink, gender, education status, public medical insurance and hypertension chi-square test are significant, BMI (OR=1.193 95%CI 1.182~1.203), age (OR =1.049, 95%CI 1.045~1.053). There is a spatial difference in the prevalence of hypertension in China, which provides a spatial reference for the control and prevention of different regions, so as to better prevent and treat patients with hypertension. Keywords: hypertension, spatial difference, CHARLS data

Taking the Xiangwang bauxite mining of Xiaoyi City, Shanxi Province as the research object, the DJi “Wu”inspire2 model Unmanned aerial vehicle (UAV) was used to obtain the video data, image data and Ground control points (GCP) data of a typical pit in the study area. Based on the two kinds of data source (video data and image data), the Digital surface model (DSM) of the research area was acquired with or without ground control points through aerial triangulation and block adjustment. Using the DSM obtained by the two data source, the distribution of elevation, slope, slope direction, surface fluctuation and surface roughness was extracted and compared. Research shows that the DSM, acquired by the ContextCapture software without GCP, using video data obtained by aerial shooting around one interest point, can qualitatively reflect the topographic distribution of the land surface. The DSM got by the video data with the GCP can achieve the similar accuracy with the result obtained by image data, and the topographic information acquired by the two kinds of data source has highly similar characteristics in spatial and numerical distribution. It can be concluded through comparison and analysis of the topographical factors that steep slopes with complex topography and large elevation difference distributes in the northwest-central of the pit, of which northwest and southwest slopes can be easily eroded by wind and rain, so attention should be paid to slop stability monitoring and disaster prevention in this area. As a whole, the results show that video data obtained by UAV can not only reflect the dynamic changes of the land surface qualitatively, but also can describe the distribution of surface topography quantitatively through processing to get the DSM. It has great application potential in the field of disaster emergency monitoring and geological hazard risk assessment in mining areas.

Phaeozem is one kind of scarce resources on the earth. Due to the restrictions of natural factors and the influence of human activities over the years, phaeozem degradation has become increasingly serious. Based on images of the ASTER in 2006 and the ETM+ in 2000 in this paper, the phaeozem organic matter content which is greater than 2 ％ was obtained by using quantitative retrieval. Through the three-dimensional remote sensing image, terrain rendering and relevant information were analyzed. On the basis of the above, the spatial distribution characteristics of phaeozem in Songliao Plain were analyzed using DEM (digital elevation model) data. The results show that the total area of phaeozem in Songliao Plain is about 51360.15 km2, and the phaeozem organic matter content is gradually increasing along with the increasing latitude or longitude, and decreasing along with increasing slope. In addition, the soil organic matter content is lower in southern slopes than that in northern slopes.

With the increasing development and utilization of mines in China, the economic development is accompanied by the destruction of the geological environment of mines. The state vigorously promotes the construction of ecological civilization, and the restoration and treatment of mine environment has become increasingly important. Based on remote sensing technology and high-resolution remote sensing image, this paper investigates the situation of mine environment restoration and treatment in Su Hu area, and discusses typical cases of mine environment restoration and treatment, so as to provide reference for mine restoration and treatment.

Taking the domestic high-resolution satellite image data obtained in 2018 as the information source, the remote sensing image was processed, and part of the map spots were verified in the field. Combined with the natural environment, topography and geomorphology of Wenzhou City, the sand mining of Oujiang, Feiyun and Aojiang in Wenzhou City was investigated and monitored by remote sensing. Through the application research, the current situation of sand mining in Wenzhou City is found out, which can provide scientific basis for the government to make the next decision of sand mining restoration and management and the reasonable development and utilization planning of mineral resources.

Rapid development of remote sensing technology has become an important means of geological hazards monitoring. Domestic high- resolution satellite data such as TH-1, ZY-3, GF1/2 and BJ-2, because of its high quality and low price, are more and more widely used in the field of geology. However, there are still some problems in data processing and the research on domestic satellite data in coal mining geological hazards monitoring is not much. So it needs further research and application. This paper aims to establish a set of technology scheme for dynamic monitoring and analysis of geological hazards in coal mining collapse area based on domestic high-resolution satellite. We selected the Xinjiang Uygur Autonomous Region Midong District of Urumqi where geological disasters are more serious as the study area, compared and analyzed the domestic high-resolution satellite images based on the TH-1 (2014), GF-1 (2015), BJ-2 (2016). This paper identified dynamic change of geologic hazard, set up the symbol of interpretation, evaluated and explored the practicability of land disaster investigation and dynamic monitoring with domestic high-resolution satellite. Based on the dynamic monitoring with domestic high-resolution satellite data from 2014 to 2016, we found that the geological disasters such as ground collapse and ground cracks are increasing. We suggest that it should be planned first, and exploitation should be scientific. It is necessary to strengthen the restoration of governance.

ain population struck by the H1N1-2009 virus was young adults, youths and children. The outbreaks most frequently occurred in schools, and most cases were acquired locally.