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Modeling temperature and moisture dependent emissions of carbon dioxide and methane from drying dairycow manure

Enzhu HU, Pakorn SUTITARNNONTR, Markus TULLER, Scott B. JONES

《农业科学与工程前沿（英文）》 2018年第5卷第2期页码 280-286 doi: 10.15302/J-FASE-2018215

摘要： Greenhouse gas emissions due to biological degradation processes of animal wastes are significant sources of air pollution from agricultural areas. The major environmental controls on these microbe-induced gas fluxes are temperature and moisture content. The objective of this study was to model the effects of temperature and moisture content on emissions of CO and CH during the ambient drying process of dairy manure under controlled conditions. Gas emissions were continuously recorded over 15 d with paired fully automated closed dynamic chambers coupled with a Fourier Transformed Infrared gas analyzer. Water content and temperature were measured and monitored with capacitance sensors. In addition, on days 0, 3, 6, 9, 12 and 15, pH, moisture content, dissolved organic carbon and total carbon (TC) were determined. An empirical model derived from the Arrhenius equation confirmed high dependency of carbon emissions on temperature and moisture content. Results indicate that for the investigated dairy manure, 6.83% of TC was lost in the form of CO and 0.047% of TC was emitted as CH . Neglecting the effect of temperature, the moisture contents associated with maximum gas emissions were estimated as 0.75 and 0.79 g·g for CO and CH , respectively.

关键词： carbon dioxide dairy manure methane moisture temperature

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The relationship between progesterone and Th-related cytokines in plasma during early pregnancy in cows

Lei CHENG,Youdong XIN,Xiaohua LIU,Xiuzhong HU,Min XIANG,Dingfa WANG,Shuhong ZHAO

《农业科学与工程前沿（英文）》 2016年第3卷第2期页码 147-152 doi: 10.15302/J-FASE-2016099

摘要： In cows, progesterone (P4) is essential for the maintenance of pregnancy and successful embryo development is dependent on the maternal immunomodulation of Th-related cytokines. However, investigation of the relationship between P4 and Th immunity in cattle remains incomplete. Therefore, we evaluated plasma P4 concentrations and expressions of three Th-related cytokines, interleukins IL-1β, IL-4 and IL-6, in 15 pregnant and 11 non-pregnant cows 0, 14, 18, 21, and 28 d post artificial insemination. Pregnant cows had significantly higher plasma P4 levels and pregnant cows with higher P4 on 14 d tended to have higher P4 in the subsequent period of pregnancy. There was no difference in IL-4 and IL-6 expression between pregnant cows and non-pregnant cows, whereas plasma IL-1β was temporally upregulated on 21 d. The cytokines measured were not affected in either the high-P4 group (>11.1 ng·mL ) or the low-P4 group (<11.1 ng·mL ) in pregnant cows. A weak negative correlation between IL-1β and IL-6 was observed, but none of the cytokines was associated with a change in plasma P4. In conclusion, there was no clear relationship between P4 and Th immunity in maternal plasma in the pregnant cows, which differs from what occurs in humans and mice during early pregnancy.

关键词： dairy cow progesterone pregnancy cytokine

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Performance analysis of solar still with cow dung cakes and blue metal stones

Hitesh N. PANCHAL

《能源前沿（英文）》 2015年第9卷第2期页码 180-186 doi: 10.1007/s11708-015-0361-y

摘要： The aims of this paper is to investigate the effects of various materials inside the solar still on the increase of the productivity of potable water. Here, blue metal stones and cow dung cakes were used as materials. To investigate their effect, three identical solar stills with an effective area of 1 m square made from locally available materials were tested in climate conditions of Mehsana (23°50′ N 72° 23′). The first and second solar stills were filled with blue metal, stones and cow dung cakes, while the third one was taken as a reference which consisted of only blue paint at the basin. The experiments show that blue metal stones have the highest distillate output at daytime, followed by cow dung cakes solar still and reference solar still. On the other hand, the overall distillate output of blue metal stones and cow dung cakes at daytime as well as at night were 35% and 20% compared with that of reference solar still.

关键词： blue metal stones cow dung cakes distillate output solar still solar intensity

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HARNESSING BIODIVERSITY FOR HEALTHY DAIRY FARMS

《农业科学与工程前沿（英文）》 2022年第9卷第2期页码 238-244 doi: 10.15302/J-FASE-2022445

摘要：

Producing sufficient high-quality forage to meet the increasing domestic demand for safe and nutritious milk products is one of the critical challenges that Chinese dairy farms are facing. The increased forage biomass production, mainly contributed by agrochemicals inputs in China, is accompanied by tremendous impacts on the ecology of dairy farms and soil quality. This paper presents a framework for healthy dairy farms in which targeted management practices are applied for quality milk products with minimal adverse environmental impacts. The paper also summarizes biodiversity management practices at the field and landscape scales toward lessening inputs of water, fertilizers, pesticides and mitigating soil compaction. Dairy farming with biodiversity-driven technologies and solutions will be more productive in producing quality milk and minimizing environmental damage.

关键词： biodiversity / dairy farm / one health concept / soil health

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NEW ZEALAND DAIRY FARM SYSTEMS AND KEY ENVIRONMENTAL EFFECTS

Jiafa LUO, Stewart LEDGARD

《农业科学与工程前沿（英文）》 2021年第8卷第1期页码 148-158 doi: 10.15302/J-FASE-2020372

摘要： This paper provides an overview of the range of dairy pasture grazing systems used in New Zealand (NZ), the changes with increased inputs over time and associated key environmental effects including nitrogen (N) leaching and greenhouse gas (GHG) emissions. NZ dairy farming systems are based on year-round grazing and seasonal milk production on perennial ryegrass/clover pasture where cows are rotationally grazed in paddocks. There was an increase in stocking rate on NZ dairy farms from 2.62 cows ha in 2000/2001 to 2.85 cows ha in 2015/2016. During the same period annual milk solids production increased from 315 to 378 kg·yr per cow. This performance has coincided with an increase in N fertilizer use (by 30%) and a twofold increase in externally-sourced feeds. Externally-sourced feeds with a low protein concentration (e.g., maize silage) can increase the efficiency of N utilization and potentially reduce N losses per unit of production. Off-paddock facilities (such as standoff or feed pads) are often used to restrict grazing during very wet winter conditions. A systems analysis of contrasting dairy farms in Waikato (largest NZ dairying region) indicates that the increased input would result in an increase in per-cow milk production but little change in efficiency of milk production from a total land use perspective. This analysis also shows that the increased inputs caused an 11% decrease in N footprint (i.e., N emissions per unit of milk production) and a 2% increase in C footprint (i.e., greenhouse gas (GHG) emissions per unit of milk production).

关键词： dairy farms environmental impacts grazing systems intensification mitigation

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NEW ZEALAND DAIRY FARM SYSTEMS AND KEY ENVIRONMENTAL EFFECTS

《农业科学与工程前沿（英文）》 2021年第8卷第1期

摘要：

• NZ dairy farming systems are based on year-round grazing of perennial pasture (ryegrass/white clover).

• Milk production per hectare has increased by about 29% with increased use of externally-sourced feeds over the last two decades.

• Externally-sourced feeds with a low protein concentration can potentially reduce N₂O emissions and N leaching per unit of production.

• Systems analysis is important for evaluating mitigations to minimize trade-offs between environmental impacts.

This paper provides an overview of the range of dairy pasture grazing systems used in New Zealand (NZ), the changes with increased inputs over time and associated key environmental effects including nitrogen (N) leaching and greenhouse gas (GHG) emissions. NZ dairy farming systems are based on year-round grazing and seasonal milk production on perennial ryegrass/clover pasture where cows are rotationally grazed in paddocks. There was an increase in stocking rate on NZ dairy farms from 2.62 cows ha⁻¹ in 2000/2001 to 2.84 cows ha⁻¹ in 2015/2016. During the same period annual milk solids production increased from 315 to 378 kg·yr⁻¹per cow. This performance has coincided with an increase in N fertilizer use (by ~ 30%) and a twofold increase in externally-sourced feeds. Externally-sourced feeds with a low protein concentration (e.g., maize silage) can increase the efficiency of N utilization and potentially reduce N losses per unit of production. Off-paddock facilities (such as standoff or feed pads) are often used to restrict grazing during very wet winter conditions. A systems analysis of contrasting dairy farms in Waikato (largest NZ dairying region) indicates that the increased input would result in an increase in per-cow milk production but little change in efficiency of milk production from a total land use perspective. This analysis also shows that the increased inputs caused an 11% decrease in N footprint (i.e., N emissions per unit of milk production) and a 2% increase in C footprint (i.e., greenhouse gas (GHG) emissions per unit of milk production).jiafa.luo@agresearch.co.nz

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NUMERICAL MODELING OF BIOMASS GASIFICATION USING COW DUNG AS FEEDSTOCK

《农业科学与工程前沿（英文）》 2023年第10卷第3期页码 458-467 doi: 10.15302/J-FASE-2023500

摘要：

● Gasification of cow dung was evaluated using Aspen Plus software.

关键词： Aspen Plus biomass gasification manure of livestock and poultry simulation syngas

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ASSESSMENT OF HEAVY METALS IN HYDROCHAR PRODUCED BY HYDROTHERMAL CARBONIZATION OF DAIRY MANURE

《农业科学与工程前沿（英文）》 2023年第10卷第3期页码 437-447 doi: 10.15302/J-FASE-2023507

摘要：

● Content of heavy metals in hydrochar varies considerably, from 50% to 100%.

关键词： heavy metals dairy manure hydrochar hydrothermal carbonization waste management

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Evaluation of automated in-line precision dairy farming technology implementation in three dairy farms

Maria CARIA, Giuseppe TODDE, Antonio PAZZONA

《农业科学与工程前沿（英文）》 2019年第6卷第2期页码 181-187 doi: 10.15302/J-FASE-2019252

摘要：

In recent decades, dairy farms have been exposed to wide variation in profit levels due to a considerable variability of milk price, and energy and feed costs. Consequently, it is necessary for the dairy industry to improve efficiency and productivity by adopting innovative technologies. The automated in-parlour milk analysis and separation is mainly useful to produce low or high quality milk and to monitor the animal health status. Milk with high levels of protein and fat contents may reduce the intensity of standardization during cheesemaking process, reducing production costs. The study aimed to evaluate the efficiency of real-time milk separation during milking and the performance of the milking machine after implementation of AfiMilk MCS. In addition, the economic aspects were assessed. The separation of milk required the existing milking parlors to be equipped with an additional milkline to allow channeling milk with low and high coagulation properties into two different cooling tanks. The results showed that the high coagulation milk fraction, compared to the bulk milk, increased in fat (from 18% to 43%) and protein (from 3% to 7%) concentration. The technology tested has given promising results showing reliability and efficiency in milk separation in real time with affordable implementation costs.

关键词： cheese yield infrared analysis milk quality real-time measurement sensor

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INTENSIFICATION OF GRASSLAND-BASED DAIRY PRODUCTION AND ITS IMPACTS ON LAND, NITROGEN AND PHOSPHORUS

《农业科学与工程前沿（英文）》 2021年第8卷第1期

摘要：

• Monitoring data of>5000 dairy farms collected and examined in uniform manner.

• Environmental performances of farms influenced by government regulations.

• N and P surpluses at farm level remained about constant with intensity level.

• N and P use efficiencies at farm, herd and soil increased with intensity level.

• Accounting for externalization of off-farm feed production affects NUE and PUE.

• Ammonia emissions per kg milk decreased with the level of intensification.

Many grassland-based dairy farms are intensifying production, i.e., produce more milk per ha of land in response to the increasing demand for milk (by about 2% per year) in a globalized market. However, intensive dairy farming has been implicated for its resources use, ammonia and greenhouse gas emissions, and eutrophication impacts. This paper addresses the question of how the intensity of dairy production relates to N and P surpluses and use efficiencies on farms subjected to agri-environmental regulations. Detailed monitoring data were analyzed from 2858 grassland-based dairy farms in The Netherlands for the year 2015. The farms produced on average 925 Mg·yr⁻¹ milk. Milk production per ha ranged from<10 to>30 Mg·ha⁻¹·yr⁻¹. Purchased feed and manure export strongly increased with the level of intensification. Surpluses of N and P at farm level remained constant and ammonia emissions per kg milk decreased with the level of intensification. In conclusion, N and P surpluses did not differ much among dairy farms greatly differing in intensity due to legal N and P application limits and obligatory export of manure surpluses to other farms. Further, N and P use efficiencies also did not differ among dairy farms differing in intensity provided the externalization of feed production was accounted for. This paper provides lessons for proper monitoring and control of N and P cycling in dairy farming.

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病毒性疾病对奶牛繁殖力的重要影响 Review

D. Claire Wathes, Chike F. Oguejiofor, Carole Thomas, Zhangrui Cheng

《工程（英文）》 2020年第6卷第1期页码 26-33 doi: 10.1016/j.eng.2019.07.020

摘要：

世界各地的牛群中有许多病毒性疾病是地方性疾病。许多病毒穿过胎盘并导致流产和胎儿畸形的能力是众所周知的。还有大量证据表明，病毒感染对于奶牛还有其他影响，反映在受胎率的降低上。但是，这些影响很大程度上取决于单个动物首次感染该疾病的时间，因此难以量化。本文介绍了5种可能影响奶牛繁殖力的病毒，以及它们的潜在作用机制。妊娠中期非细胞病变型牛病毒性腹泻病毒（bovine viral diarrhea virus, BVDV）的急性感染会使流产率升高或导致持续感染的犊牛出生。在临近配种期感染BVDV会直接影响卵巢和子宫内膜，导致发情周期不规律和早期胚胎死亡。BVDV诱发的免疫抑制也可能降低繁殖力，从而增加对细菌的易感性。牛疱疹病毒（bovine herpesvirus, BHV）-1型在青春期前的小母牛中最常见，会导致它们生长减缓，延迟繁殖并提高首次产犊的年龄，先前受感染的动物继而表现出繁殖力的降低。尽管这可能与肺损伤有关，但也有卵巢病变的相关报告。初次感染后，BHV-1和BHV-4都潜伏在宿主中，并且可能在以后由于应激而重新激活，如与产犊和早期泌乳有关的应激。虽然仅感染BHV-4可能不会降低繁殖力，但它似乎与已建立的细菌病原体（如大肠杆菌和化脓隐秘杆菌）共同作用，促进子宫内膜炎的发展并延迟产犊后母牛的子宫修复机制。施马伦贝格病毒（Schmallenberg virus, SBV）和蓝舌病病毒（bluetongue virus, BTV）均以昆虫作为媒介传播，导致流产率和先天畸形的增加。BTV-8同时还损害孵出囊泡的发育；此外，任何一种病毒在繁殖前后的感染基本都会降低受胎率。尽管受胎率的降低通常难以量化，但足以造成经济损失，这有助于衡量疫苗接种和根除方案的效益。

关键词：牛病毒性腹泻病毒牛疱疹病毒1型牛疱疹病毒4型施马伦贝格病毒蓝舌病毒免疫抑制胚胎死亡率

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INTENSIFICATION OF GRASSLAND-BASED DAIRY PRODUCTION AND ITS IMPACTS ON LAND, NITROGEN AND PHOSPHORUS

Jouke OENEMA, Oene OENEMA

《农业科学与工程前沿（英文）》 2021年第8卷第1期页码 130-147 doi: 10.15302/J-FASE-2020376

摘要： Many grassland-based dairy farms are intensifying production, i.e., produce more milk per ha of land in response to the increasing demand for milk (by about 2% per year) in a globalized market. However, intensive dairy farming has been implicated for its resources use, ammonia and greenhouse gas emissions, and eutrophication impacts. This paper addresses the question of how the intensity of dairy production relates to N and P surpluses and use efficiencies on farms subjected to agri-environmental regulations. Detailed monitoring data were analyzed from 2858 grassland-based dairy farms in The Netherlands for the year 2015. The farms produced on average 925 Mg·yr milk. Milk production per ha ranged from<10 to>30 Mg·ha ·yr . Purchased feed and manure export strongly increased with the level of intensification. Surpluses of N and P at farm level remained constant and ammonia emissions per kg milk decreased with the level of intensification. In conclusion, N and P surpluses did not differ much among dairy farms greatly differing in intensity due to legal N and P application limits and obligatory export of manure surpluses to other farms. Further, N and P use efficiencies also did not differ among dairy farms differing in intensity provided the externalization of feed production was accounted for. This paper provides lessons for proper monitoring and control of N and P cycling in dairy farming.

关键词： ammonia externalization feed forage maize front runners manure production milk yield nitrogen surplus

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Global warming potential associated with Irish milk powder production

William Finnegan, Jamie Goggins, Aksana Chyzheuskaya, Xinmin Zhan

《环境科学与工程前沿（英文）》 2017年第11卷第3期 doi: 10.1007/s11783-017-0949-z

摘要： Climate change is an ever growing issue and a major concern worldwide. Both producers and processors need to address the issue now by reducing their carbon footprint. Additionally, if Ireland is to meet their climate and energy targets, as outlined in Food Harvest 2020, which outlines a range of objectives for the Irish agricultural sector, the efficient use of resources and fuels within the industry will need to be increased. In Ireland, agriculture accounts for 29.2% of the total greenhouse gas emissions (58.5 million tonnes CO eq). Therefore, in this paper, a single agri-food product, milk powder, is examined in order to estimate the global warming potential (GWP) associated with its manufacture using life cycle assessment. A cradle-to-processing factory gate analysis, which includes raw milk production, raw milk transportation to the processing factory, its processing into each product and product packaging, is assessed in this study using data collected circa 2013. The factories surveyed processed approximately 24% of the total raw milk processed in the Republic of Ireland in 2013, which was 5.83 billion liters. The average total GWP associated with the manufacture of milk powder is 9.731 kg CO eq·kg milk powder, which has a standard deviation of 2.26 kg CO eq·kg milk powder, for the life cycle stages analyzed in this study. The most significant contributor to GWP is raw milk production (84%), followed by dairy processing (14%), with the remainder of the life cycle stages contributing approximately 2%.

关键词： Dairy Global warming potential Ireland Life cycle assessment Milk powder Milk production

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通过厌氧分批处理香蕉皮提高沼气产量 Article

Spyridon Achinas, Janneke Krooneman, Gerrit Jan Willem Euverink

《工程（英文）》 2019年第5卷第5期页码 970-978 doi: 10.1016/j.eng.2018.11.036

摘要：

废物处置和能源危机是大多数国家面临的重要挑战。水果加工业每天产生数吨废物，其中大部分来自香蕉农场。厌氧消化（AD）技术已被应用于废水、污泥、食物垃圾和农业剩余物的处理，其主要目的是生产能源和消除废物。本研究探讨有机负荷（OL）和牛粪（CM）添加对处理香蕉皮废料（BPW）时AD性能的影响。在OL为每升18 g和22 g挥发性固体（gvs）时，CM含量为10%、20%和30%的香蕉皮（BP）每日最大沼气产量分别为50.20 mL·g_vs^–1、48.66 mL·g_vs^–1、62.78 mL·g_vs^–1和40.49 mL·g_vs^–1、29.57 mL·g_vs^–1、46.54 mL·g_vs^–1。然而，每日沼气产量与OL或CM含量没有明显的相关性。此外，动力学分析表明，一阶模型和锥体模型的动力学参数受工艺参数的影响。

关键词：沼气香蕉皮牛粪厌氧处理分批试验动力学研究

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NUTRIENT USE EFFICIENCY AND LOSSES OF INDUSTRIAL FARMS AND MIXED SMALLHOLDINGS: LESSONS FROM THE NORTH CHINA PLAIN

Yifei MA, Ling ZHANG, Zhaohai BAI, Rongfeng JIANG, Yong HOU, Lin MA

《农业科学与工程前沿（英文）》 2021年第8卷第1期页码 58-71 doi: 10.15302/J-FASE-2020371

摘要： The proportion of industrial livestock in China has increased over the past 30 years, which increases animal performance but causes the decoupling of crop and livestock production. Here, we aimed to quantify nutrient flows, nutrient use efficiency, and nutrient losses in different livestock systems in the North China Plain based on the NUFER-farm model. Activity data were collected by face-to-face surveys on pig and dairy (41 livestock farms) during 2016–2018. The two systems included industrial farms and mixed smallholdings. In mixed smallholdings, 4.0% and 9.6% of pig and dairy feed dry matter (DM) were derived from household farmland, but 4.8% and 9.3% of manure DM recycled to household farmland. Nutrient use efficiency in industrial farms was higher than in mixed smallholdings at animal level, herd level, and system level. To produce 1 kg N and P in animal products, nutrient losses in industrial pig farms (2.0 kg N and 1.3 kg P) were lower than in mixed pig smallholdings, nutrient losses in industrial dairy farms (2.7 kg N and 2.2 kg P) were slightly higher than in mixed dairy smallholdings. Liquid manure discharge in industrial farms was the main losses pathway in contrast to mixed smallholdings. This study suggests that feed localization can reduce nutrient surpluses at the district level. It is necessary to improve manure management and increase the degree of integrated crop-livestock in smallholdings. In industrial farms, it is desirable to increase the liquid manure recycling ratio through cooperating livestock and crop production at the district level.

关键词： industrial farms mixed smallholdings pig dairy nutrient management