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Modulations of genes related to gut integrity,apoptosis,and immunity underlie the beneficial effects of Bacillus amyloliquefaciens CECT 5940 in broilers fed diets with different protein levels in a necrotic enteritis challenge model 被引量:6
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作者 Kosar Gharib-Naseri Juliano Cesar de Paula Dorigam +4 位作者 Kiran Doranalli Sarbast Kheravii obert A.Swick Mingan Choct Shu-Biao Wu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2021年第2期626-638,共13页
Background:The ban of in-feed antimicrobial additives has negatively affected the poultry industry by causing necrotic enteritis(NE)to emerge in the flocks.Alternatives such as Bacillus probiotics have shown to be eff... Background:The ban of in-feed antimicrobial additives has negatively affected the poultry industry by causing necrotic enteritis(NE)to emerge in the flocks.Alternatives such as Bacillus probiotics have shown to be effective on eliminating the negative effects of this disease.Two experiments were conducted to investigate the effect of Bacillus amyloliquefaciens CECT 5940(BA)in broiler chickens under NE challenge and/or fed diets with different protein levels.Methods:In both experiments,480 day-old mix-sexed Ross-308 broilers were arranged in a 2×2 factorial arrangement of treatments.In experiment 1,the factors were NE challenge(yes or no)and probiotic(yes or no).In experiment 2,the factors were dietary crude protein levels(standard or reduced)and probiotic(yes or no)and were used under NE challenge condition.Oral administration of Eimeria oocysts(day 9)followed by inoculation with Clostridium perfringens(day 14 and 15)was used to induce NE challenge.On day 16,two birds from each treatment were gavaged with fluorescein isothiocyanate-dextran(FITC-d)and blood samples were collected for gut integrity evaluation,and jejunal samples were collected for gene expression assay.Results:In experiment 1,BA supplementation decreased caspase-3(CASP3)(P<0.001)and caspase-8(CASP8)(P<0.05)and increased occludin(OCLD)(P<0.05)expression regardless of the challenge.Additionally,BA supplementation downregulated interfron-γ(IFN-γ)expression(P<0.01)and upregulated immunoglobulin-G(IgG)(P<0.01)and immunoglobulin-M(IgM)(P<0.05)only in challenged birds.In experiment 2,the expression of genes encoding mucin-2(MUC2)(P<0.001),tight junction protein-1(TJP1)(P<0.05)and OCLD(P<0.05)were upregulated by the addition of BA in the diet,regardless of the crude protein level.Further,BA supplementation downregulated INF-γ(P<0.01)and upregulated immunoglobulin-A(IgA)(P<0.05),IgM(P<0.05)and IgG(P<0.01)regardless of the crude protein level.Conclusion:These findings suggest that supplementation of BA in broiler diets can improve gut health by modulation of genes related to the mucosal barrier,tight junction,and immunity in broilers challenged by unfavourable conditions such as NE challenge. 展开更多
关键词 Bacillus amyloliquefaciens BROILER Clostridium perfringens Gene expression Necrotic enteritis Probiotic
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Soil Salinity Mapping and Monitoring in Arid and Semi-Arid Regions Using Remote Sensing Technology: A Review 被引量:15
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作者 Amal Allbed Lalit Kumar 《Advances in Remote Sensing》 2013年第4期373-385,共13页
Soil salinity is a serious environmental problem especially in arid and semiarid areas. It either occurs naturally or is human-induced. High levels of soil salinity negatively affect crop growth and productivity leadi... Soil salinity is a serious environmental problem especially in arid and semiarid areas. It either occurs naturally or is human-induced. High levels of soil salinity negatively affect crop growth and productivity leading land degradation ultimately. Thus, it is important to monitor and map soil salinity at an early stage to enact effective soil reclamation program that helps lessen or prevent future increase in soil salinity. Remote sensing has outperformed the traditional method for assessing soil salinity offering more informative and professional rapid assessment techniques for monitoring and mapping soil salinity. Soil salinity can be identified from remote sensing data obtained by different sensors by way of direct indicators that refer to salt features that are visible at the soil surface as well as indirect indicators such as the presence of halophytic plant and assessing the performance level of salt-tolerant crops. The purposes of this paper are to 1) discuss some soil salinity indicators;2) review the satellite sensors and methods used for remote monitoring, detecting and mapping of soil salinity, particularly in arid and semi-arid regions;3) review various spectral vegetation and salinity indices that have been developed and proposed for soil salinity detection and mapping, with an emphasis on soil salinity mapping and assessment in arid and semi-arid regions;and 4) highlight the most important issues limiting the use of remote sensing for soil salinity mapping, particularly in arid and semi-arid regions. 展开更多
关键词 Soil SALINITY REMOTE SENSING Halophytic PLANT SALINITY INDEX
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Investigating the Use of Remote Sensing and GIS Techniques to Detect Land Use and Land Cover Change: A Review 被引量:5
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作者 Abdullah F. Alqurashi Lalit Kumar 《Advances in Remote Sensing》 2013年第2期193-204,共12页
The accuracy of change detection on the earth’s surface is important for understanding the relationships and interactions between human and natural phenomena. Remote Sensing and Geographic Information Systems (GIS) h... The accuracy of change detection on the earth’s surface is important for understanding the relationships and interactions between human and natural phenomena. Remote Sensing and Geographic Information Systems (GIS) have the potential to provide accurate information regarding land use and land cover changes. In this paper, we investigate the major techniques that are utilized to detect land use and land cover changes. Eleven change detection techniques are reviewed. An analysis of the related literature shows that the most used techniques are post-classification comparison and principle component analysis. Post-classification comparison can minimize the impacts of atmospheric and sensor differences between two dates. Image differencing and image ratioing are easy to implement, but at times they do not provide accurate results. Hybrid change detection is a useful technique that makes full use of the benefits of many techniques, but it is complex and depends on the characteristics of the other techniques such as supervised and unsupervised classifications. Change vector analysis is complicated to implement, but it is useful for providing the direction and magnitude of change. Recently, artificial neural networks, chi-square, decision tree and image fusion have been frequently used in change detection. Research on integrating remote sensing data and GIS into change detection has also increased. 展开更多
关键词 CHANGE Detection TECHNIQUES REMOTE Sensing GIS LAND Use and LAND COVER CHANGE
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An Essential Oil Blend Decreases Methane Emissions and Increases Milk Yield in Dairy Cows 被引量:2
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作者 Kenton J. Hart Hefin G. Jones +3 位作者 Kate E. Waddams Hilary J. Worgan Beatrice Zweifel C. Jamie Newbold 《Open Journal of Animal Sciences》 2019年第3期259-267,共9页
This study was conducted to investigate the effect of a commercial essential oil (EO) additive on milk production and methane (CH4) emissions from dairy cows. Early lactation Holstein-Friesian dairy cows were fed gras... This study was conducted to investigate the effect of a commercial essential oil (EO) additive on milk production and methane (CH4) emissions from dairy cows. Early lactation Holstein-Friesian dairy cows were fed grass, whole crop wheat and corn silage total mixed ration. Cows were allocated to one of two experimental treatments: Control (no additive, CON) or 1 g/head/day of EO. Cows were housed in a free stall barn, split into two pens for the duration of the experiment. Two gas data loggers units used to measure CH4 emissions were provided per pen for the duration of the 22 week-long study. Milk yield was determined daily, and milk components were analyzed every two weeks. CH4 was recorded continuously, and daily values were tabulated. Body weight and body condition score were determined at the start and bi-weekly. Results were analyzed as a randomized complete block trial. In total, 149 cows participated in the study (76 CON, 73 EO). Milk yields were greater (P < 0.05) for the test treatment (28.3 CON, 31.2 EO) with no change in milk component concentrations. Milk component concentrations were unaffected (P > 0.05) by treatment. Yields of fat, protein, lactose, and solids were higher for EO fed cows (P 4 output was reduced with the EO compared to the CON treatment (411 g/day vs 438 g/day;13.8 g/L of milk vs 17.2 g/L of milk, P < 0.05) over the duration of the trial. There were no effects of treatment on reproductive performance or the occurrence of mastitis. Feeding EO to dairy cows reduced CH4 emissions whilst also increasing performance. 展开更多
关键词 DAIRY COWS Essential OILS Methane Milk Yield
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A multi-channel chemical sensor and its application in detecting hydrothermal vents 被引量:1
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作者 Zhen Cai A J Mur Luis +3 位作者 Jiwan Han Kui Wang Huawei Qin Ying Ye 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第9期128-134,共7页
There are well-established chemical and turbidity anomalies in the plumes occurring vicinity of hydrothermal vents, which are used to indicate their existence and locations. We here develop a small, accurate multi-cha... There are well-established chemical and turbidity anomalies in the plumes occurring vicinity of hydrothermal vents, which are used to indicate their existence and locations. We here develop a small, accurate multi-channel chemical sensor to detect such anomalies which can be used in deep-sea at depths of more than 4 000 m. The design allowed five all-solid-state electrodes to be mounted on it and each (apart from one reference electrode) could be changed according to chemicals to be measured. Two experiments were conducted using the chemical sensors. The first was a shallow-sea trial which included sample measurements and in situ monitoring. pH, Eh, CO3^2- and SO4^2- electrodes were utilized to demonstrate that the chemical sensor was accurate and stable outside the laboratory. In the second experiment, the chemical sensor was integrated with pH, Eh, CO3^2- and H2S electrodes, and was used in 29 scans of the seabed along the Southwest Indian Ridge (SWIR) to detect hydrothermal vents, from which 27 sets of valid data were obtained. Hydrothermal vents were identified by analyzing the chemical anomalies, the primary judging criteria were decreasing voltages of Eh and H2S, matched by increasing voltages of pH and CO3^2- . We proposed that simultaneous detection of changes in these parameters will indicate a hydrothermal vent. Amongst the 27 valid sets of data, five potential hydrothermal vents were targeted using the proposed method. We suggest that our sensors could be widely employed by marine scientists. 展开更多
关键词 CHEMICAL sensor MULTI-CHANNEL HYDROTHERMAL VENTS detection CHEMICAL ANOMALIES SWIR
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Land Use and Land Cover Change Detection in the Saudi Arabian Desert Cities of Makkah and Al-Taif Using Satellite Data 被引量:1
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作者 Abdullah F. Alqurashi Lalit Kumar 《Advances in Remote Sensing》 2014年第3期106-119,共14页
Land use/land cover (LULC) changes have become a central issue in current global change and sustainability research. Saudi Arabia has undergone significant change in land use and land cover since the government embark... Land use/land cover (LULC) changes have become a central issue in current global change and sustainability research. Saudi Arabia has undergone significant change in land use and land cover since the government embarked on a course of intense national development 30 years ago, as a result of huge national oil revenues. This study evaluates LULC change in Makkah and Al-Taif, Saudi Arabia from 1986 to 2013 using Landsat images. Maximum likelihood and object-oriented classification were used to develop LULC maps. The change detection was executed using post-classification comparison and GIS. The results indicated that urban areas have increased over the period by approximately 174% in Makkah and 113% in Al-Taif. Analysis of vegetation cover over the study area showed a variable distribution from year to year due to changing average precipitation in this environment. Object-based classification provided slightly greater accuracy than maximum likelihood classification. Information provided by satellite remote sensing can play an important role in quantifying and understanding the relationship between population growth and LULC changes, which can assist future planning and potential environmental impacts of expanding urban areas. 展开更多
关键词 LAND Use/Cover Patterns LANDSAT IMAGERY Makkah Al-Taif Urban Growth Image Classification Change Detection
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The influence of phytase, pre-pellet cracked maize and dietary crude protein level on broiler performance via response surface methodology
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作者 Amy F.Moss Peter V.Chrystal +2 位作者 Yueming Dersjant-Li Peter H.Selle Sonia Yun Liu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2020年第1期169-182,共14页
Background:The reduction of crude protein levels in diets for broiler chickens may generate economic,environmental and flock welfare and health benefits;however,performance is usually compromised.Whole grain feeding a... Background:The reduction of crude protein levels in diets for broiler chickens may generate economic,environmental and flock welfare and health benefits;however,performance is usually compromised.Whole grain feeding and phytase may improve the utilization of reduced crude protein diets.Results:The effects of pre-pellet cracked maize(0,15%and 30%)and phytase(0,750 and 1500 FTU/kg)in isoenergetic maize-soy diets with three levels of crude protein(22%,19.5%and 17%)were evaluated via a BoxBehnken response surface design.Each of 13 dietary treatments were offered to 6 replicate cages(6 birds/cage)of male Ross 308 broiler chicks from 7 to 28 d post-hatch.Model prediction and response surface plots were generated from experimental data via polynomial regression in R and only significant coefficients were included and discussed in the predicted models.Weight gain,feed intake and FCR were all influenced by pre-pellet cracked maize,phytase and crude protein level,where crude protein level had the greatest influence.Consequently,the reduction from 22%to 17%dietary crude protein in non-supplemented diets reduced weight gain,feed intake,relative gizzard weight,relative gizzard content and relative pancreas weight but improved FCR.However,the inclusion of 30%cracked maize to 17%crude protein diets restored gizzard weight and 1500 FTU phytase inclusion to 17%crude protein diets increased relative gizzard contents and pancreas weights.Cracked maize and phytase inclusion in tandem to 17%crude protein diets increased weight gain,feed intake and FCR;however,this FCR was still more efficient than broilers offered the non-supplemented 22%crude protein diet.Broilers offered the prepellet cracked maize and phytase inclusions reduced AME in 22%crude protein diets but improved AME by 2.92 MJ(14.16 versus 11.24 MJ;P<0.001)in diets containing 17%crude protein.Ileal N digestibility was greater in broilers offered diets with 17%crude protein than those offered the 22%crude protein diet;irrespective of phytase and pre-pellet cracked maize.Conclusion:Pre-pellet cracked maize and phytase inclusions will improve the performance of broilers offered reduced crude protein diets. 展开更多
关键词 CRUDE protein MAIZE PHYTASE Pre-pellet whole grain Response surface
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Identification of BoLA DRB3.2 Alleles Present in White Fulani and Muturu Cattle Breeds
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作者 Ridwan O. Ahmed Semiu F. Bello Matthew J. Hegarty 《Open Journal of Animal Sciences》 2020年第4期725-734,共10页
Cattle production is an important aspect of animal agriculture. Disease predisposition in cattle can lead to lowered productivity and poor animal welfare. To select and breed for the fittest cattle population, it is e... Cattle production is an important aspect of animal agriculture. Disease predisposition in cattle can lead to lowered productivity and poor animal welfare. To select and breed for the fittest cattle population, it is expedient that we understand the genetic basis of disease tolerance/resistance. Major histocompatibility complex (MHC) is a vital component of the immune system in vertebrates. Its genes are crucial determinants for immune response and resistance to infectious diseases. The bovine MHC is referred to as Bovine Lymphocyte antigen (BoLA) with its most functional and highly variable region located in the exon 2 (BoLA-DRB3.2). Over 100 alleles of BoLA-DRB3.2 have been identified in cattle and many studies have associated polymorphism in this region with disease resistance/susceptibility. In this study, we investigated the polymorphic nature of BoLA-DRB3.2 in the White Fulani and Muturu cattle breeds using a single PCR-sequence based typing. We identified 26 and 25 alleles in White Fulani and Muturu breeds, respectively, with only six alleles being mutual in the two breeds. Some of the alleles identified in this study have been noted as markers for disease status in cattle. BoLA-DRB3*014:01:01, BoLA-DRB3*011:01, and BoLA-DRB3*008:01 alleles have been associated with Bovine leukemia virus (BLV) resistance in cattle. BoLA-DRB3*014:01:01, BoLA-DRB3*001:01, and BoLA-DRB3*011:01 were linked with mastitis resistance in Japanese Holstein cows. While no inference can be drawn in terms of association with disease status, this study confirms the highly polymorphic and diverse nature of BoLA-DRB3 in White Fulani and Muturu cattle breeds. 展开更多
关键词 Major Histocompatibility Complex Bovine Lymphocyte Antigen (BoLA) POLYMORPHISM White Fulani Muturu
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Modelling Impacts of Climate Change on Maize (<i>Zea mays</i>L.) Growth and Productivity: A Review of Models, Outputs and Limitations
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作者 Benjamin Kipkemboi Kogo Lalit Kumar +1 位作者 Richard Koech Philip Langat 《Journal of Geoscience and Environment Protection》 2019年第8期76-95,共20页
The use of crop modelling in various cropping systems and environments to project and upscale agronomic decision-making under the facets of climate change has gained currency in recent years. This paper provides an ev... The use of crop modelling in various cropping systems and environments to project and upscale agronomic decision-making under the facets of climate change has gained currency in recent years. This paper provides an evaluation of crop models that have been used by researchers to simulate maize growth and productivity. Through a systematic review approach, a comprehensive assessment of 186 published articles was carried out to establish the models and parameterization features, simulated impacts on maize yields and adaptation strategies in the last three decades. Of the 23 models identified, CERES-maize and APSIM models were the most dominant, representing 49.7% of the studies undertaken between 1990 and 2018. Current research shows projected decline in maize yields of between 8% - 38% under RCP4.5 and RCP8.5 scenarios by the end of the 21st century, and that adaptation is essential in alleviating the impacts of climate change. Major agro-adaptation options considered in most papers are changes in planting dates, cultivars and crop water management practices. The use of multiple crop models and multi-model ensembles from general circulation models (GCMs) is recommended. As interest in crop modelling grows, future work should focus more on suitability of agricultural lands for maize production under climate scenarios. 展开更多
关键词 Crop MODELLING Climate Scenarios MAIZE Simulation GCM
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An Investigation of Polymorphism in <i>SMO</i>and <i>LMF</i>1 Genes and Their Association with Body Size in White Fulani and Muturu Cattle Breeds
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作者 Ridwan O. Ahmed Semiu F. Bello +1 位作者 Ibrahim Shu’aibu Matthew J. Hegarty 《Advances in Bioscience and Biotechnology》 2020年第7期319-344,共26页
Cattle production is integral to the people of Africa and her economy. To <span style="font-family:Verdana;">improve cattle productivity, there is a need to inculcate molecular mark</span><spa... Cattle production is integral to the people of Africa and her economy. To <span style="font-family:Verdana;">improve cattle productivity, there is a need to inculcate molecular mark</span><span style="font-family:Verdana;">er-assisted selection into current breeding practices. In this study, we investigated, in </span><span style="font-family:Verdana;">White Fulani and Muturu cattle breeds, polymorphism of two candidate</span><span style="font-family:Verdana;"> genes (Smoothened—</span><i><span style="font-family:Verdana;">SMO</span></i><span style="font-family:Verdana;"> and Lipase Maturation Factor 1—</span><i><span style="font-family:Verdana;">LMF</span></i><span style="font-family:Verdana;">1</span><span style="font-family:Verdana;">) that have been reported to influence body size in cattle. The </span><i><span style="font-family:Verdana;">SMO</span></i><span style="font-family:Verdana;"> gene encodes for the SMO </span><span style="font-family:Verdana;">(smoothened) receptor protein;a membrane signal transducer that plays a</span><span style="font-family:Verdana;"> role in the control of bone formation and adipogenesis. </span><i><span style="font-family:Verdana;">LMF</span></i><span style="font-family:Verdana;">1 </span><span style="font-family:Verdana;">encodes for the </span><span style="font-family:Verdana;">LMF1 protein which regulates post-translational maturation of vascular li</span><span style="font-family:Verdana;">pases. Desired regions of the genes were amplified and genotyped by direct </span><span style="font-family:Verdana;">DNA sequencing or Polymerase chain reaction—Restriction Fragment</span><span style="font-family:Verdana;"> Length </span><span style="font-family:Verdana;">Polymorphism. For association study, linear body measurements traits</span><span style="font-family:Verdana;"> (BMTs) that can be used to predict body size were measured on each animal and values of BMTs measured were compared between both breeds. Very significant (P < 0.001) differences, in favour of White Fulani, were observed for all the BMTs compared. Six (6) previously reported SNP (G21234C, C22424T and C22481T, T22939C, C23329T and T23458G) were found on the </span><i><span style="font-family:Verdana;">SMO</span></i><span> </span><span style="font-family:Verdana;">while </span><i><span style="font-family:Verdana;">LMF</span></i><span style="font-family:Verdana;">1</span><span style="font-family:Verdana;"> was monomorphic at the expected (T > C) exon 4 mutation site. Association analysis revealed that polymorphism on G21234C, C22424T, T22939C and T23458G loci significantly affected BMTs (P < 0.05 or 0.01) in both cattle breeds. The outcome of this study showed that </span><i><span style="font-family:Verdana;">SMO</span></i><span style="font-family:Verdana;"> gene could be a useful </span><span style="font-family:Verdana;">candidate gene to facilitate marker assisted selection for body size while </span><i><span style="font-family:Verdana;">LMF</span></i><span style="font-family:Verdana;">1</span><span style="font-family:Verdana;"> is monomorphic in the cattle breeds.</span> 展开更多
关键词 SMOOTHENED Lipase Maturation Factor 1 Body Measurement Traits White Fulani Muturu POLYMORPHISM
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Living Off Wetlands: A Case Study of Mara Bay and Masirori Wetlands, Tanzania
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作者 David Omolo Philip Kibet Langat +1 位作者 Richard Koech Yong Jiang 《Journal of Geoscience and Environment Protection》 2018年第12期43-60,共18页
This study was undertaken to help highlight the negative impacts of economic activities on wetlands in East Africa with a specific focus on Mara Bay and Masirori wetlands, Tanzania, a region where the local communitie... This study was undertaken to help highlight the negative impacts of economic activities on wetlands in East Africa with a specific focus on Mara Bay and Masirori wetlands, Tanzania, a region where the local communities still harness wetland resources for economic sustenance. Key economic activities and the negative impacts of the income-generating activities on the wetlands are identified, including the main goods harnessed, level of dependency of the locals to the wetlands, and the level of environmental knowledge of the locals on the wetlands’ ecosystem services. Both qualitative and quantitative tools and techniques viz.: questionnaires, semi-structured interviews, market surveys and spreadsheet analysis were used in this study. The proportion of wetland users involved in papyrus harvesting, food crop cultivation and fishing was 30%, 25% and 24%, respectively while charcoal/firewood and grass for livestock accounted for 12% and 7%, respectively. Significant differences in incomes for charcoal (p < 0.05) across the four villages were recorded but farming, fishing, mat making, herding and fish mongering were non-significant. About 6% of those interviewed had some considerable knowledge on wetland ecosystem services, while the rest (94%) lacked information. Issues identified as having detrimental impacts on the wetlands’ ecosystem services included conversion of sections of the wetlands into farmlands, grazing, charcoal burning, unsustainable fishing, overharvesting of papyrus and brick-making. Farming was found to be a major income-generating activity within the two wetlands. Other important economic activities were charcoal burning, fishing, mat making and fish mongering. The findings from the research are useful for devising appropriate strategies for wetland conservation. Such measures may include assigning wetland ecologists to the village governments, valuation of the wetlands, commissioning of a price and resource regulatory board for the wetland goods, creation of wetlands monitoring program, a fining regime system and a roll-out of mass environmental education in the wetlands regions. 展开更多
关键词 WETLANDS WETLANDS GOODS WETLANDS ECOSYSTEM Services WETLAND MARKS Economic SUSTENANCE Livelihoods
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Are there Monthly Variations in Water Quality in the Amman, Zarqa and Balqa Regions, Jordan?
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作者 Khaled A. Alqadi Lalit Kumar 《Computational Water, Energy, and Environmental Engineering》 2013年第2期26-35,共10页
This study investigated the monthly variation of water quality in the Amman-Zarqa and Balqa regions in Jordan in terms of pH, ammonium, nitrate and conductivity. During 2004 there was no monthly variation in water qua... This study investigated the monthly variation of water quality in the Amman-Zarqa and Balqa regions in Jordan in terms of pH, ammonium, nitrate and conductivity. During 2004 there was no monthly variation in water quality for most of the tested parameters. All readings were above the accepted range except for pH, indicating that land use does have an impact on water quality irrespective of urban, industrial or agricultural usage. The water quality remained for the most part below the maximum levels for drinking standards in Jordan, but these standards are often below the WHO recommendations. The pH was found to fluctuate through the year. Nitrate levels were highly seasonal in irrigated lands but remained stable over basin covered by other land uses. Ammonium levels were high in areas of urbanisation and intensive animal husbandry as a consequence of effluent infiltration, peaking during the wet season due to increased infiltration. These results indicate that, over an annual cycle, the variation in water quality remains constant;however the continued drawdown of the aquifer system will inevitably lead to deterioration in the parameters investigated. 展开更多
关键词 Water Quality pH AMMONIUM CONDUCTIVITY NITRATE
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高糖黑麦草在陇中黄土高原和河西绿洲引种试验初报 被引量:4
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作者 成慧 Eun Joong Kim 侯扶江 《草业科学》 CAS CSCD 北大核心 2011年第6期978-982,共5页
在陇中黄土高原和河西绿洲引入3种高糖黑麦草(Lolium perenne,HSR)‘明星’、‘神奇’和‘阿旺’。第1次刈割,在2个区域,HSR品种的可溶性碳水化合物含量均显著高于对照品种‘普通’(P<0.05);第2次刈割,在陇中黄土高原HSR品种的可溶... 在陇中黄土高原和河西绿洲引入3种高糖黑麦草(Lolium perenne,HSR)‘明星’、‘神奇’和‘阿旺’。第1次刈割,在2个区域,HSR品种的可溶性碳水化合物含量均显著高于对照品种‘普通’(P<0.05);第2次刈割,在陇中黄土高原HSR品种的可溶性碳水化合物含量显著高于对照及河西绿洲HSR品种中的‘神奇’和‘阿旺’(P<0.05)。2个区域HSR品种的中性洗涤纤维、酸性洗涤纤维、粗蛋白等与对照品种差异不显著(P>0.05),但产量较低。在陇中黄土高原刈割增加分蘖密度、粗蛋白、中性洗涤纤维和酸性洗涤纤维含量,降低可溶性碳水化合物含量;而在河西绿洲呈现相反趋势。 展开更多
关键词 高糖黑麦草 可溶性碳水化合物 中性洗涤纤维 酸性洗涤纤维 粗蛋白 黄土高原 绿洲
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Role of live microbial feed supplements with reference to anaerobic fungi in ruminant productivity: A review 被引量:17
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作者 Anil K Puniya Abdelfattah Z M Salem +7 位作者 Sanjay Kumar Sumit S Dagar Gareth W Griffith Monica Puniya Sreenivas R Ravella Nikhil Kumar Tejpal Dhewa Ravinder Kumar 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第3期550-560,共11页
To keep the concept of a safe food supply to the consumers, animal feed industries world over are showing an increasing interest in the direct-fed microbials(DFM) for improved animal performance in terms of growth or ... To keep the concept of a safe food supply to the consumers, animal feed industries world over are showing an increasing interest in the direct-fed microbials(DFM) for improved animal performance in terms of growth or productivity. This becomes all the more essential in a situation, where a number of the residues of antibiotics and/or other growth stimulants reach in milk and meat with a number of associated potential risks for the consumers. Hence, in the absence of growth stimulants, a positive manipulation of the rumen microbial ecosystem to enhance the feedstuff utilization for improved production efficiency by ruminants has become of much interest to the researchers and entrepreneurs. A few genera of live microbes(i.e., bacteria, fungi and yeasts in different types of formulations from paste to powder) are infrequently used as DFM for the domestic ruminants. These DFM products are live microbial feed supplements containing naturally occurring microbes in the rumen. Among different DFM possibilities, anaerobic rumen fungi(ARF) based additives have been found to improve ruminant productivity consistently during feeding trials. Administration of ARF during the few trials conducted, led to the increased weight gain, milk production, and total tract digestibility of feed components in ruminants. Anaerobic fungi in the rumen display very strong cell-wall degrading cellulolytic and xylanolytic activities through rhizoid development, resulting in the physical disruption of feed structure paving the way for bacterial action. Significant improvements in the fiber digestibility were found to coincide with increases in ARF in the rumen indicating their role. Most of the researches based on DFM have indicated a positive response in nutrient digestion and methane reducing potential during in vivo and/or in vitro supplementation of ARF as DFM. Therefore, DFM especially ARF will gain popularity but it is necessary that all the strains are thoroughly studied for their beneficial properties to have a confirmed ‘generally regarded as safe' status for ruminants. 展开更多
关键词 微生物饲料添加剂 反刍动物 厌氧真菌 生产效率 动物生产性能 直接饲喂微生物 瘤胃真菌 纤维素降解
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First report on Guanshan Biota(Cambrian Stage 4) at the stratotype area of Wulongqing Formation in Malong County, Eastern Yunnan, China 被引量:4
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作者 Feiyang Chen Zhifei Zhang +2 位作者 Marissa J. Betts Zhiliang Zhang Fan Liu 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第4期1459-1476,共18页
Exceptionally preserved fossils,such as those from Cambrian Burgess Shale-type fossil-Lagerstatten are critical because of their unique contributions to knowledge of the phylogenetic radiation and palaeoecological exp... Exceptionally preserved fossils,such as those from Cambrian Burgess Shale-type fossil-Lagerstatten are critical because of their unique contributions to knowledge of the phylogenetic radiation and palaeoecological expansion of metazoans during the Cambrian explosion.Critically,these deposits provide information that is usually unobtainable from shelly and skeletonized fossils alone.The Guanshan Biota(Cambrian Series 2,Stage 4)in the Yunnan Province of South China,has produced abundant and diverse,exquisitely preserved fossils that often retain soft tissues and organs.To date,most fossils from the Guanshan Biota have been collected from localities such as Gaoloufang and Gangtoucun,which have become inaccessible due to new urban expansions and constructions of residential buildings.Here we present the first report of soft bodied fossils from a new section at Kanfuqing,close to the Wulongqing village in Malong County,approximately 3 km east of the Wulongqing Formation stratotype section.Fossils retain soft morphology,and include brachiopods with delicate marginal setae,priapulids with well-preserved sclerites and vetulicolians with entire sections of body.In addition,this fauna includes rare occurrences of trilobites preserved with soft tissues replicated as pyrite pseudomorphs after weathering.This discovery represents an important palaeogeographical extension of soft-bodied fossils of the Guanshan fauna to the east of the Xiaojiang Fault(related to Tsinning tectonic movements ca.700 Ma).The fauna from the new Kanfuqing section is similar to that reported from the Wulongqing Formation west of the Xiaojiang Fault,and thus has significant implications for early Cambrian palaeogeography,faunal successions and palaeoenvironments of eastern Yunnan. 展开更多
关键词 Guanshan BIOTA Early CAMBRIAN Xiaojiang Fault EASTERN YUNNAN PALAEOENVIRONMENT PALAEOGEOGRAPHY
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黄土高原高糖黑麦草的产量和品质预测 被引量:5
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作者 王永嘉 成慧 +3 位作者 Eun Joong Kim Nigel Scollan 常生华 侯扶江 《草业科学》 CAS CSCD 北大核心 2017年第9期1863-1879,共17页
为探明黄土高原高糖黑麦草(Lolium perenne)粗蛋白、粗脂肪、中性洗涤纤维、酸性洗涤纤维、粗灰分、可溶性碳水化合物等指标及产草量与其生长时间、株高、分蘖之间的关系,本研究采用田间试验结合预测模型的方法,利用生长时间、株高、分... 为探明黄土高原高糖黑麦草(Lolium perenne)粗蛋白、粗脂肪、中性洗涤纤维、酸性洗涤纤维、粗灰分、可溶性碳水化合物等指标及产草量与其生长时间、株高、分蘖之间的关系,本研究采用田间试验结合预测模型的方法,利用生长时间、株高、分蘖对高糖黑麦草在模拟轮牧和收获干草两种利用方式下的牧草产量及品质进行预测。结果表明,收获干草的Aberavon、Aberstar、Premium和Abermagic黑麦草生长时间、株高和分蘖均与各营养指标显著相关(P<0.05);模拟轮牧的Aberavon、Aberstar、Premium和Abermagic黑麦草株高与各营养指标均不相关(P>0.05),生长时间、分蘖与粗蛋白、粗灰分之外的其它品质指标均显著相关(P<0.05)。利用生长时间、株高、分蘖对4个黑麦草品种的产草量和饲用成分建立一元回归预测和多元回归预测模型,经预测值与实测值对比,预测结果准确度均较高,可为高糖黑麦草在黄土高原栽培和利用提供科学依据。 展开更多
关键词 放牧 分蘖 株高 粗蛋白 粗脂肪 粗纤维 可溶性碳水化合物
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Using MiddRAD-seq data to develop polymorphic microsatellite markers for an endangered yew species 被引量:4
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作者 Hantao Qin Guoqian Yang +2 位作者 Jim Provan Jie Liu Lianming Gao 《Plant Diversity》 SCIE CAS CSCD 北大核心 2017年第5期294-299,共6页
Microsatellites are highly polymorphic markers which have been used in a wide range of genetic studies.In recent years, various sources of next-generation sequencing data have been used to develop new microsatellite l... Microsatellites are highly polymorphic markers which have been used in a wide range of genetic studies.In recent years, various sources of next-generation sequencing data have been used to develop new microsatellite loci, but compared with the more common shotgun genomic sequencing or transcriptome data, the potential utility of RAD-seq data for microsatellite ascertainment is comparatively under-used.In this study, we employed MiddRAD-seq data to develop polymorphic microsatellite loci for the endangered yew species Taxus florinii. Of 8,823,053 clean reads generated for ten individuals of a population, 94,851(~1%) contained microsatellite motifs. These corresponded to 2993 unique loci, of which 526(~18%) exhibited polymorphism. Of which, 237 were suitable for designing microsatellite primer pairs, and 128 loci were randomly selected for PCR validation and microsatellite screening. Out of the 128 primer pairs, 16 loci gave clear, reproducible patterns, and were then screened and characterized in 24 individuals from two populations. The total number of alleles per locus ranged from two to ten(mean=4.875), and within-population expected heterozygosity from zero to 0.789(mean = 0.530),indicating that these microsatellite loci will be useful for population genetics and speciation studies of T. florinii. This study represents one of few examples to mine polymorphic microsatellite loci from ddRAD data. 展开更多
关键词 MiddRAD-seq Endangered species Microsatellite Next-generation sequencing Taxus florinii
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Effect of stripe rust on the yield response of wheat to nitrogen 被引量:3
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作者 Rakhesh Devadas Steven Simpfendorfer +1 位作者 David Backhouse David W.Lamb 《The Crop Journal》 SCIE CAS 2014年第4期201-206,共6页
Nitrogen(N) is the most important fertiliser element determining the productivity of wheat.N nutrition is known to affect the level of stripe rust infection, with higher N associated with increased disease severity. S... Nitrogen(N) is the most important fertiliser element determining the productivity of wheat.N nutrition is known to affect the level of stripe rust infection, with higher N associated with increased disease severity. Stripe rust, caused by Puccinia striiformis f. sp. tritici, is a major yield-limiting disease of wheat in Australia. This paper describes experiments designed to investigate the agronomic response to the interaction of various levels of N application and stripe rust severity in wheat varieties differing in response. Experimental plots were established in crop seasons 2006 and 2007 on the Liverpool Plains of northern NSW, Australia.Yield, biomass, grain protein content(GPC) and harvest index(HI) data were recorded.Increased rates of N increased the severity of stripe rust during grain filling. N application also increased yield and GPC in all varieties in both years. Stripe rust reduced the yield of the rust-susceptible wheat varieties, and GPC and proportion of added N recovered in the grain were also reduced in one year but not the other. It was evident from our experiment that stripe rust caused yield loss accompanied by either no change or reduction in GPC, indicating that the total amount of N entering the grain was reduced by stripe rust. The effects of stripe rust on N yield are most likely associated with reduced uptake of N during grain filling. 展开更多
关键词 PUCCINIA STRIIFORMIS Yield GRAIN protein NITROGEN DEFICIENCY
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The different root apex zones contribute to drought priming induced tolerance to a reoccurring drought stress in wheat 被引量:2
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作者 Xiao Wang Jing Chen +6 位作者 Jiakun Ge Mei Huang Jian Cai Qin Zhou Tingbo Dai Luis Alejandro Jose Mur Dong Jiang 《The Crop Journal》 SCIE CSCD 2021年第5期1088-1097,共10页
Drought priming is a promising approach to improve tolerance to further drought in wheat.The root apex plays important roles in drought however,its contribution to drought priming remains unknown.To provide mechanisti... Drought priming is a promising approach to improve tolerance to further drought in wheat.The root apex plays important roles in drought however,its contribution to drought priming remains unknown.To provide mechanistic insights into this process,the transcriptomes and proteomes at three different zones along the root axis under drought stress were analyzed.Physiological assessment of root growth indicated that priming augmented roots growth in response to drought and also the levels of protective proline and glycine betaine.Scanning across the proximal to the distal zones of the root apex indicated increases the transcription of genes involved in primary and secondary metabolism.Conversely,genes related to translation,transcription,folding,sorting and degradation,replication and repair were increased in the apex compared to the proximal zone.A single drought episode suppressed their expression but prior drought priming served to maintain expression with recurrent drought stress.The differentially primed responses genes were mainly involved in the pathways related to plant hormone signaling,stress defense and cell wall modification.The prediction of regulatory hubs using Cytoscape implicated signaling components such as the ABA receptor PYL4 as influencing antioxidant status and the cell cycle.Based our integrative transcriptomic-proteomic assessments we present a model for drought priming protected plant hormone signaling transduction pathways to drive the cell cycle and cell wall loosening to confer beneficial effects on roots to counter the effects of drought.This model provides a theoretical basis for improvement of drought tolerance in wheat,via an increased understanding of drought priming induced drought tolerance. 展开更多
关键词 WHEAT Drought priming Drought tolerance Root Transcriptome
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Sensory quality of meat from eight different types of cattle in relation with their biochemical characteristics 被引量:3
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作者 M Gagaoua E M C Terlouw +8 位作者 D Micol J-F Hocquette A P Moloney K Nuernberg D Bauchart A Boudjellal N D Scollan R I Richardson B Picard 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第7期1550-1563,共14页
The present study compared eight breeds of cattle differing in gender(heifers, bulls and steers) to determine associations between muscle characteristics and meat sensory qualities of the Longissimus thoracis muscle. ... The present study compared eight breeds of cattle differing in gender(heifers, bulls and steers) to determine associations between muscle characteristics and meat sensory qualities of the Longissimus thoracis muscle. Animal types differed in all the muscle characteristics and sensory qualities. Many correlations among muscle characteristics and among sensory qualities were consistent for most animal types. Isocitrate dehydrogenase(ICDH) activities allowed discrimination of muscles with respect to myosin heavy chain(My HC)-I proportions for all animal types. Lactate dehydrogenase(LDH) and phosphofructokinase(PFK) activities were positively correlated for most animal types. Overall liking was correlated with beef flavour and abnormal flavour in all animal types and with global tenderness for all animal types except for Charolais cross breed steers. For all animal types except for Angus×Friesian heifers, beef flavour and abnormal flavour were negatively correlated. Overall liking was not correlated with juiciness. PFK, ICDH and citrate synthase(CS) activities were strongly associated with tenderness, beef flavour and overall liking when average values for all animal types were used. However, associations between muscle characteristics and sensory qualities within animal types were weak and inconsistent. 展开更多
关键词 动物类型 感官质量 生化特性 胸肌肉 阉牛 异柠檬酸脱氢酶 黑白花母牛 肌球蛋白重链
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