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A review of the effects of dietary organic acids fed to swine

Journal of Animal Science and Biotechnology 2016年第1期7卷 67-77页

作者： Mocherla V A N Suiryanrayna J V Ramana livestock research station Sri Venkateswara Veterinary University

Animal production depends on nutrient utilization and if done there is an accelerated momentum towards growth with a low cost to feed ratio Public concern over the consumption of pork with antibiotic residues of the animals fed with antibiotic growth promoters （AGP） has paved the way to use other additives like herbs and their products, probiotics, prebiotics etc. Numerous feed additives are in vogue for achieving this target and one such classical example is the usage of organic acids and their salts. Usage of organic acids was in progress for over four decades. Early weaned piglets are （3-4 weeks age） exposed to stress with a reduced feed intake, little or no weight gain. This post weaning lag period is due to a limited digestive and absorptive capacity due to insufficient production of hydrochloric acid, pancreatic enzymes and sudden changes in feed consistency and intake. Lowering dietary pH by weak organic acids was found to overcome these problems. The main activity of organic acids is associated with a reduction in gastric pH converting the inactive pepsinogen to active pepsin for effective protein hydrolysis. Organic acids are both bacteriostatic and bactericidal. Lactic acid has been reported to reduce gastric pH and delay the multiplication of an enterotoxigenic E. coil These acids are the intermediary products in Kreb＇s cycle and thus act as an energy source preventing the tissue breakdown resulting from gluconeogenesis and lipolysis. Excretion of supplemental minerals and nitrogen are minimized with organic acids as these form complexes with minerals and aids for their bio-availability. Short chain fatty cids like acetic, propionic and n-butyric acid produced by microbial fermentation of dietary fibre in the large intestines may increase the proliferation of epithelial cells and have stimulatory effects on both endocrine and exocrine pancreatic secretions in pigs. Organic acids also enhances apparent total tract digestibility and improves growth performa

关键词： Chelation Improved productivity Organic acids Pathogen inhibition Protein utility Swine

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Effect of Senescence Retardants on the Quality of Persian Lime Fruits

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Phyton-International Journal of Experimental Botany 2024年第8期93卷 1805-1818页

作者： Rafael Ariza-Flores Rafael Ambriz-Cervantes Pedro Cadena-Iñiguez Luis A.Gálvez-Marroquín Miguel A.Cano-García National Institute of Forestry Agriculture and Livestock Research(INIFAP)South Pacific Regional CenterSanto Domingo Barrio BajoVilla de EtlaOaxaca68200México National Institute of Forestry Agriculture and Livestock Research(INIFAP)Zacatepec Research StationZacatepecMorelos62780México National Institute of Forestry Agriculture and Livestock Research(INIFAP)Central Chiapas Research StationOcozocoautlaChis29140México National Institute of Forestry Agriculture and Livestock Research(INIFAP)Oaxaca Central Valley Research StationSanto Domingo Barrio BajoVilla de EtlaOaxaca68200México

The objective of this study consisted of evaluating the effect of the application of chitosan(Q),1-methylcyclopropene(1-MCP)under two controlled temperatures on some physical,physiological,and chemical parameters contributing to the quality of Persian lime Citrus latifolia *** treatments were evaluated,resulting from the combination of four senescence retardant applications(Q,1-MCP,1-MCP+Q,and without application)on fruits stored at two temperatures(12/20℃.Epidermis color(luminosity,chromaticity,and hue),fruit appearance,respiration,weight loss,total juice content,total soluble solids,and titratable acidity were registered during the *** results indicate that the 1-MCP and Q combination favored fruit postharvest quality conditions such as reducing respiration rate;maintaining fruit good appearance,turgidity,and brighter fruit chromaticity;fruits treated with chitosan and stored at 12℃,favored total soluble *** the other hand,Variables such as weight loss,juice content,acidity,phenols,flavonoids,antioxidant activity,and hue values were favored by a 12℃ storing temperature regardless of the *** general,the use of modified atmospheres,senescence retardants,and refrigeration as postharvest methods,can increase Persian lime shelf life.

关键词： Citrus latifolia quality conservation organic alternatives

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Assessing risks and uncertainties in forest dynamics under different management scenarios and climate change

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Forest Ecosystems 2015年第3期2卷 169-189页

作者： Matthias Albert Jan Hansen Jürgen Nagel Matthias Schmidt Hermann Spellmann Northwest German Forest research station

Background: Forest management faces a climate induced shift in growth potential and increasing current and emerging new risks. Vulnerability analysis provides decision support based on projections of natural resources taking risks and uncertainties into account. In this paper we(1) characterize differences in forest dynamics under three management scenarios,(2) analyse the effects of the three scenarios on two risk factors, windthrow and drought stress, and(3) quantify the effects and the amount of uncertainty arising from climate projections on height increment and drought ***: In four regions in northern Germany, we apply three contrasting management scenarios and project forest development under climate change until 2070. Three climate runs(minimum, median, maximum) based on the emission scenario RCP 8.5 control the site-sensitive forest growth functions. The minimum and maximum climate run define the range of prospective climate ***: The projections of different management regimes until 2070 show the diverging medium-term effects of thinnings and harvests and long-term effects of species conversion on a regional scale. Examples of windthrow vulnerability and drought stress reveal how adaptation measures depend on the applied management path and the decision-maker’s risk attitude. Uncertainty analysis shows the increasing variability of drought risk projections with time. The effect of climate projections on height growth are quantified and uncertainty analysis reveals that height growth of young trees is dominated by the age-trend whereas the climate signal in height increment of older trees is ***: Drought risk is a serious issue in the eastern regions independent of the applied silvicultural scenario,but adaptation measures are limited as the proportion of the most drought tolerant species Scots pine is already high. Windthrow risk is no serious overall threat in any region, but adequate counter-measures such as spec

关键词： Climate change Silvicultural management strategies

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Variation of Zn content in soils under different land-use types in the Hetao oasis,Inner Mongolia of China

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Journal of Arid Land 2016年第6期8卷 861-870页

作者： ZHU Yangchun ZHAO Xueyong LIAN Jie CHEN Min Naiman Desertification research station/Urat Desert-grassland research station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

Understanding the status and distribution of the micronutrient Zn in soils is important for managing plant growth and preventing soil pollution for agricultural irrigation systems in arid and semi-arid regions. In this study, a total of 195 soil samples from five soil layers （0-20, 20-40, 40-60, 60-80 and 80-100 cm） in the three land-use types （wasteland, forestland and cropland） after long-term agricultural fertilization and irrigation with Yellow River water were collected in the middle of the Hetao oasis, i.e. the Yongji irrigation sub-oasis. We analyzed the vertical and spatial distributions of Zn content and its relationship with soil properties to determine whether differences of Zn content existed in the soil profiles. The results revealed that the mean content of Zn was 107 mg/kg, 1.9 times higher than the background value （55.7 mg/kg） of the Hetao oasis and much lower than the secondary standard value （300 mg/kg） of the Chinese Environmental Quality Standard for Soils when pH〉7.5. Soil Zn contents were not significantly different and the coefficients of variation of Zn contents were less than 50% in the five soil layers. Soil Zn content was similar from southern to northern parts but increased from western to eastern parts in the sub-oasis. Soil Zn contents did not differ significantly among the three land-use types, but soil total nitrogen （TN） contents were significantly higher in the agriculturally managed forestland and cropland than in the wasteland （P〈0.05）. Zn was significantly and positively correlated with TN （F=36.6, P〈0.001）. The use of fertilizers may increase the content of Zn in soils, but flooding irrigation may minimize the differences in the spatial distribution of soil Zn content in the whole sub-oasis. This research is of important value for soil pollution control and sustainable land use management in arid and semi-arid regions.

关键词： fertilizer land-use type spatial distribution soil profile soil property

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Gene expression of CCL8 and CXCL10 in peripheral blood leukocytes during early pregnancy in cows

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Journal of Animal Science and Biotechnology 2018年第4期9卷 813-823页

作者： Ryosuke Sakumoto Kosuke Iga Ken-Go Hayashi Shiori Fujii Hiroko Kanahara Misa Hosoe Tadashi Furusawa Division of Animal Breeding and Reproduction research Institute of Livestock and Grassland Science National Agriculture and Food Research Organization (NARO) Division of livestock and Forage research Tohoku Agricultural Research CenterNARO Division of Animal Sciences Institute of Agrobiological SciencesNARO

Background: The aim of the present study was to evaluate CCL8 and CXCL10 expression and its regulatory mechanism in peripheral blood leukocytes(PBLs) at the time of maternal recognition in cows. Blood samples were collected on 14, 15, 16, 17 and 18 d after artificial insemination(AI). Based on the day of return of estrus, cows were divided into three groups, pregnant(n = 5), early embryonic mortality(EEM; n = 5) and late embryonic mortality(LEM; n = 5). The gene expression levels in PBLs were assessed with quantitative real-time reverse transcription ***: The expression of CCL8 and CXCL10 mRNA in PBLs gradually increased from 14 to 18 d of pregnant cows and significant differences were observed on 18 d(P < 0.05), whereas no significant changes were observed both in EEM and LEM cows. Interferon-stimulated protein 15 k Da(ISG15), myxovirus-resistance gene(MX) 1 and MX2 mRNA expression in PBLs increased from 14 to 18 d which was significant on 18 d of pregnant cows as well as in LEM cows(P < 0.05), but no changes were observed in EEM cows. To determine whether the expression of CCL8 and CXCL10 in PBLs was regulated by pregnancy-related substances or not, expression level was assessed after exposure to interferon-τ(IFNT) and CCL16. Monocytes, granulocytes and lymphocytes were obtained using density-gradient centrifugation and flow cytometry. The addition of IFNT(100 ng/mL) and CCL16(100 ng/mL) to cultured PBLs increased the expression of CCL8 and CXCL10 mRNA(P < 0.05). The expression of ISG15, MX1 and MX2 mRNA in PBLs was also stimulated by IFNT and CCL16(P < 0.05).Conclusions: The expression of CCL8 and CXCL10 genes increased in PBLs during early pregnancy. Since IFNT stimulated CCL8 and CXCL10 expression in cultured PBLs, the increase of CCL8 and CXCL10 might be pregnancy-dependent *** expression of both CCL8 and CXCL10 in PBLs was stimulated by CCL16 as wel as IFNT, suggesting a chemokine interaction that at least includes CCL8, CXCL10 and CCL16, and m

关键词： CCL8 Cow CXCL10 Leukocytes Pregnancy

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Predicting Ailanthus altissima presence across a managed forest landscape in southeast Ohio

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Forest Ecosystems 2019年第4期6卷 261-273页

作者： Louis R.Iverson Joanne Rebbeck Matthew P.Peters Todd Hutchinson Timothy Fox Northern research station USDA Forest Service

Background: The negative impacts of the exotic tree, Ailanthus altissima(tree-of-heaven, stink tree), is spreading throughout much of the Eastern United States. When forests are disturbed, it can invade and expand quickly if seed sources are ***: We conducted studies at the highly dissected Tar Hollow State Forest(THSF) in southeastern Ohio USA,where Ailanthus is widely distributed within the forest, harvests have been ongoing for decades, and prescribed fire had been applied to about a quarter of the study area. Our intention was to develop models to evaluate the relationship of Ailanthus presence to prescribed fire, harvesting activity, and other landscape characteristics, using this Ohio location as a case study. Field assessments of the demography of Ailanthus and other stand attributes(e.g., fire, harvesting, stand structure) were conducted on 267 sample plots on a 400-m grid throughout THSF,supplemented by identification of Ailanthus seed-sources via digital aerial sketch mapping during the dormant season. Statistical modeling tools Random Forest(RF), Classification and Regression Trees(CART), and Maxent were used to assess relationships among attributes, then model habitats suitable for Ailanthus ***: In all, 41 variables were considered in the models, including variables related to management activities, soil characteristics, topography, and vegetation structure(derived from LiDAR). The most important predictor of Ailanthus presence was some measure of recent timber harvest, either mapped harvest history(CART) or LiDARderived canopy height(Maxent). Importantly, neither prescribed fire or soil variables appeared as important predictors of Ailanthus presence or absence in any of the models of the ***: These modeling techniques provide tools and methodologies for assessing landscapes for Ailanthus invasion, as well as those areas with higher potentials for invasion should seed sources become available. Though a case study on

关键词： Ohio Random Forest CART Maxent Landscape model Non-native invasive species

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Effect of recombinant and native buffalo OVGP1 on sperm functions and in vitro embryo development: a comparative study

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Journal of Animal Science and Biotechnology 2018年第1期9卷 99-110页

作者： Suman Choudhary A.Kumaresan Manish Kumar Shivani Chhillar Hrudananda Malik Sudarshan Kumar Jai K.Kaushik Tirtha K.Datta Ashok K.Mohanty Animal Biotechnology Centre National Dairy Research Institute livestock and Production Management Section National Dairy Research Institute

Background： An oviduct-specific glycoprotein, OVGP1, is synthesized and secreted by non-ciliated epithelial cells of the mammalian oviduct which provides an essential milieu for reproductive functions. The present study reports the effects of recombinant buffalo OVGP1 that lacks post-translational modifications, and native Buffalo OVGP1 isolated from oviductal tissue, on frozen-thawed sperm functions and in vitro embryo ***： The proportion of viable sperms was greater（P 〈 0.05） in the recombinant OVGP1-treated group compared to the native OVGP1-treated group at 2 h, 3 h, and 4 h of incubation. The proportion of motile sperms at3 h and 4 h of incubation; and membrane-intact sperms at 4 h was greater（P 〈 0.05） in the native OVGP1-treated group compared to the control and recombinant OVGP1-treated groups. The proportion of capacitated and acrosome-reacted sperms was greater（P 〈 0.05） in the native OVGP1-treated group compared to the recombinant OVGP1 group at 4 h. The rates of cleavage of embryos and their development to the blastocyst stage were greater（P 〈 0.05） in the presence of either native or recombinant OVGP1 in comparison to control at 10 μg/mL concentration as compared to 5 or 20 μg/***： The study suggests that both native and recombinant OVGP1 impart a positive effect on various sperm features and in vitro embryo development. However, native OVGP1 was found to have a more pronounced effect in comparison to recombinant non-glycosylated OVGP1 on various sperm functions except viability. Hence,our current findings infer that glycosylation of OVGP1 might be essential in sustaining the sperm functions but not the in vitro embryo development.

关键词： Blastocyst Capacitation Fertilization Glycoprotein In vitro fertilization Oestrus Semen Sperm

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Negative consequences of positive feedbacks in US wild-fire management

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Forest Ecosystems 2015年第2期2卷 57-66页

作者： David E Calkin Matthew P Thompson Mark A Finney Forestry Sciences Laboratory US Forest Service Rocky Mountain Research Station Fire Sciences Laboratory US Forest Service Rocky Mountain Research Station

Over the last two decades wildfire activity, damage, and management cost within the US have increased substantially. These increases have been associated with a number of factors including climate change and fuel accumulation due to a century of active fire suppression. The increased fire activity has occurred during a time of significant ex-urban development of the Wildland Urban Interface （WUI） along with increased demand on water resources originating on forested landscapes. These increased demands have put substantial pressure on federal agencies charged with wildfire management to continue and expand the century old policy of aggressive wildfire suppression. However, aggressive wildfire suppression is one of the major factors that drive the increased extent, intensity, and damage associated with the small number of large wildfires that are unable to be suppressed. In this paper we discuss the positive feedback loops that lead to demands for increasing suppression response while simultaneously increasing wildfire risk in the future. Despite a wealth of scientific research that demonstrates the limitations of the current management paradigm pressure to maintain the existing system are well entrenched and driven by the existing social systems that have evolved under our current management practice. Interestingly, US federal wildland fire policy provides considerable discretion for managers to pursue a range of management objectives however, societal expectations and existing management incentive structures result in policy implementation that is straining the resilience of fire adapted ecosystems and the communities that reside in and adjacent to them.

关键词： Wildfire suppression Wildfire paradox Wildland urban interface Resilience

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Spatial Heterogeneity of Vegetation in China

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Tsinghua Science and Technology 2007年第4期12卷 424-434页

作者：黄大明王昱生 Masae Shiyomi 柳小妮宋百敏陈俊 Shigeo Takahashi Yoshimichi Hori Yasuo Yamamura Ecology research station Department of Biological Sciences and Biotechnology Tsinghua University Grassland research station College of Animal Science and Technology Northeast Agricultural University Faculty of Science Ibaraki University Bunkyo 2-1-1 Mito 310-8512 Japan National Institute of livestock and Grassland Science 768 Senbonmatsu Nishinasuno Tochigi 329-2793 Japan

The spatial heterogeneity and ecological characteristics of 74 vegetation types and the lack of vegetation type within the 9.6 million km2 of Chinese territory were studied using data from the China vegetation map. The analysis used 877 large quadrats 10 mm×10 mm （actual size 100 km×100 km）, which covered about 8.77 million km^2. Each large-quadrat was divided into four small 5 mm×5mm quadrats （actual size 50 km×50 km）. The frequency of occurrence of all vegetation types was recorded in each small quadrat. The survey using the Shiyomi method of vegetation analysis based on the beta-binomial distribution was adopted to describe the frequency of occurrence and spatial heterogeneity for each kind of vegetation. The weighted average heterogeneity of all the vegetation types in the landscape provides a measure of the landscape level heterogeneity which describes the spatial intricacy of the existing vegetation composition. The maximum spatial vegetation heterogeneity was 0.8620 in the frigid-temperate coniferous forest of Larix （V1）, which dominates cold moist northeast China. The minimum spatial heterogeneity with a low occurrence was the Caragana tibetica in the gravel desert in the western Yellow River Hetao area. The minimum occurrence with a low spatial heterogeneity was the Monsoon rainforest on rock in Guangxi and Yunnan Provinces. The vegetation types on the Qing-Zang Plateau were found to be representative of Chinese vegetation because of the very high occurrence and spatial heterogeneity of these vegetation types. The weighted average of the heterogeneity was 0.677, while the vegetation diversity index was 3.29.

关键词： spatial heterogeneity beta-binomial distribution ecosystem evaluation Chinese vegetation

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Genetic variation for seed phosphorus and yield traits in Indian sorghum landraces and varieties

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The Crop Journal 2015年第4期3卷 358-365页

作者： Ashok Badigannavar G.Girish T.R.Ganapathi Nuclear Agriculture and Biotechnology Division Bhabha Atomic Research Centre (BARC) Agricultural research station

Phytic acid is the major storage form of phosphorus in cereals. It binds with nutritionally important metals and affects mineral bioavailability. The present study analyzed phytic acid, inorganic phosphorus(IP) content, seed weight, and grain yield in 98 sorghum landraces and varieties grown in two environments to evaluate genotypic and environmental effects and to determine trait stability. Genotypic effects and genotype × interaction were significant for phytic acid concentration and yield components. A promising landrace, Malkhed-1, had the lowest phytic acid(0.015 mg g-1)concentration, with a higher yield(70.02 g plant-1), than the check variety M-35-1 in both environments. Similarly, among the varieties, Phule Maulee showed the lowest phytic acid(0.07 mg g-1) and a higher grain yield of 53.15 g plant-1in both environments. Phytic acid and IP were negatively correlated(r =- 0.34), whereas grain yield and seed weight were positively correlated(r = 0.20). Cluster analysis based on seed phosphorus traits and yield components identified five and six clusters, respectively. Genotypes containing low phytic acid with high yield identified in this study would be helpful for increasing the bioavailability of mineral nutrients.

关键词： Phytic acid Sorghum Genetic variability Correlation

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