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Temperate pasture- or concentrate-beef production systems: steer performance, meat nutritional value, land-use, food–feed competition, economic and environmental sustainability 温带牧场或集中牛肉生产系统:阉牛性能、肉类营养价值、土地利用、食品饲料竞争、经济和环境可持续性
Pub Date : 2023-11-29 DOI: 10.1017/s0021859623000540
Peter Doyle, Edward G O'Riordan, Mark McGee, Paul Crosson, Alan K Kelly, Aidan Moloney
The objective was to evaluate steer performance, meat nutritional value, land-use, food–feed competition and both economic and environmental sustainability within temperate pasture-based suckler weanling-to-beef systems with or without (forage-only) concentrates. Post-weaning, 8-month-old, late-maturing breed steers (333 kg) were assigned to one of three systems: (1) grass silage + 1.2 kg concentrate DM (148 days), followed by pasture (123 days) and finished on ad libitum concentrates (120 days) – slaughter age, 21 months (GRAIN); (2) as per (1) but pasture (196 days) and finished on grass silage ad libitum + 3.5 kg concentrate DM (124 days) – slaughter age, 24 months (SIL + GRAIN); and (3) grass silage-only (148 days), pasture (196 days), silage-only (140 days) and finished on pasture (97 days) – slaughter age, 28 months (FORAGE). The mean target carcass weight was 390 kg for each system. Data generated were used to parameterize a farm-level beef systems model. Concentrate DM intake was 1187, 606 and 0 kg/head for GRAIN, SIL + GRAIN and FORAGE, respectively. The forage-only (FORAGE) system offers several advantages, including improved farm profitability, enhanced meat fatty acid profile and only utilized inedible human feed. Consequently, associated greenhouse gas (GHG) emissions per net human edible food produced were more favourable for FORAGE. However, compared to GRAIN, the FORAGE system had an older age at slaughter and associated increased pasture land-use and GHG emissions per animal, meat weight gain and essential amino acids gain. There are therefore inevitable trade-offs, as one beef system does not improve all sustainability and GHG emission metrics.
目的是评估温带牧场乳牛断奶制牛肉系统中使用或不使用(纯饲料)精料的阉牛性能、肉类营养价值、土地利用、食品饲料竞争以及经济和环境可持续性。断奶后8月龄的晚熟阉牛(333公斤)被分配到以下三种系统中的一种:(1)草料青贮+ 1.2公斤精料DM(148天),然后是牧草(123天),最后是自由采食精料(120天)-屠宰年龄21个月(GRAIN);(2)按(1)但牧场(196 d),饲喂自由青贮草地+ 3.5 kg精料DM (124 d) -屠宰日龄,24个月(SIL + GRAIN);(3)全青贮(148 d)、全青贮(196 d)、全青贮(140 d)、全放牧(97 d) -屠宰年龄28月龄(饲料)。每个系统的平均目标胴体重为390公斤。生成的数据用于参数化农场级牛肉系统模型。籽粒、SIL +籽粒和饲粮的精料干物质采食量分别为1187、606和0 kg/头。仅供饲料(FORAGE)系统具有几个优点,包括提高农场盈利能力,增强肉类脂肪酸分布,并且只使用不可食用的人类饲料。因此,每生产一种人类净食用食品的相关温室气体(GHG)排放量对草料更有利。然而,与GRAIN相比,饲草系统的屠宰年龄更大,相关的牧场土地利用和每头动物的温室气体排放量增加,肉重增加和必需氨基酸增加。因此,不可避免地存在权衡,因为一个牛肉系统并不能改善所有的可持续性和温室气体排放指标。
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引用次数: 0
The effect of tissue mobilization and stage of lactation on energy partitioning in lactating sows: an analysis of commercial data 组织动员和泌乳阶段对泌乳母猪能量分配的影响:商业数据分析
Pub Date : 2023-11-24 DOI: 10.1017/s0021859623000564
Josep Gasa, S. Capalbo, Jennifer Ellis, David Sola, James France
The objective of this paper was to investigate how the predicted level of body energy mobilized and the stage of lactation affects performance and energy partitioning in lactating sows kept under commercial conditions. Seventy-seven lactating sows from three consecutive batches were weaned at 28 d and all measures were taken over the first 20 d. Total feed consumption was measured and sows’ live weight was registered when entering the lactation facilities and at 21 d of lactation. Blood samples were collected at farrowing and once a week thereafter. Net energy (NE) mobilization or loss was calculated by difference using the general NRC equation for ME partitioning. Compared to low mobilizers (low NE loss values), high mobilizing sows had lower feed intake and higher loss of live weight, body fat and body protein. High mobilizers also weaned more piglets and had heavier litters than low mobilizers. Energy mobilization (NE loss) was higher from day 1 to 10 of lactation compared to day 11 to 20, and the difference in mobilized energy between high and low mobilizing sows was also higher in the first than in the second half of lactation. Body weight and back fat thickness losses were significantly correlated with NE loss. A more accurate prediction of the changes in live weight or back fat thickness over lactation should help better predict total amount of energy mobilized, and more research is needed to assess the relative contribution of lean and fat to mobilized tissue.
本研究旨在探讨在商业条件下饲养的泌乳母猪,机体能量动员水平和泌乳阶段对其生产性能和能量分配的影响。连续3批77头泌乳母猪在28 d断奶,在前20 d采取所有措施。在进入泌乳设施和泌乳21 d时测量总饲料消耗量并登记母猪活重。产时采集血样,此后每周采集一次。净能(NE)的调动或损失是用通用的NRC方程来计算的。与低动员母猪(低NE损失值)相比,高动员母猪采食量更低,活重、体脂和体蛋白损失更高。与低动员者相比,高动员者断奶仔猪更多,产仔更重。能量动员(NE损失)在泌乳第1 ~ 10天高于第11 ~ 20天,且高动员母猪和低动员母猪在泌乳第1 ~ 10天的动员能差异也高于泌乳第11 ~ 20天。体重和背部脂肪厚度损失与NE损失显著相关。更准确地预测哺乳期间活重或背部脂肪厚度的变化有助于更好地预测动员的总能量,需要更多的研究来评估瘦肉和脂肪对动员组织的相对贡献。
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引用次数: 0
Weather indices during reproductive phase explain wheat yield variability 生殖期天气指数解释了小麦产量变异
Pub Date : 2023-11-24 DOI: 10.1017/s0021859623000503
Ketema Tilahun Zeleke, Muhuddin Anwar, Livinus Emebiri, David Luckett
When water and nutrients are not limiting, and pests and disease are effectively controlled, crop growth and yield is determined by weather conditions such as temperature and solar radiation. To determine the relationship between weather indices and crop yield, multiple wheat varieties were sown at two sowing times, for five sowing seasons and at two locations. The following weather indices around the 50% anthesis stage were recorded and analysed: mean temperature (Tmean), maximum temperature (Tmax), number of days with temperature >30°C (T30), vapour pressure deficit (VPD), photosynthetically active radiation, photothermal quotient (PQ) and photothermal quotient corrected for vapour pressure deficit (PQvpd). Overall, for every 1°C rise in temperature, crop yield decreased by 370 kg/ha. For every 1°C rise in temperature, normal sowing window yield decreased by 360 kg/ha while late-sown wheat yield decreased by 640 kg/ha. Correlation analysis was conducted between the weather indices and grain number, grain yield and grain protein. There was a significant positive correlation between PQ and PQvpd and grain number and grain yield. There was a significant negative correlation between Tmean, Tmax, T30 and VPD and grain number and grain yield. Grain protein content showed a positive correlation with maximum air temperature and a negative correlation with the weather indices PQ and PQvpd. PQ and PQvpd can be used to predict grain number and grain yield potential. This study showed that grain number and grain yield predicted using PQ and PQvpd are more reliable than using temperature and radiation individually.
当水分和养分不受限制,病虫害得到有效控制时,作物生长和产量取决于温度和太阳辐射等天气条件。为了确定天气指标与作物产量的关系,在两个地点、五个播种季节、两个播种期播种多个小麦品种。记录和分析了花期50%前后的天气指标:平均温度(Tmean)、最高温度(Tmax)、30°C的日数(T30)、蒸汽压亏缺(VPD)、光合有效辐射、光热商(PQ)和经蒸汽压亏缺校正的光热商(PQvpd)。总体而言,温度每升高1°C,作物产量就会减少370公斤/公顷。温度每升高1℃,正常播窗产量减少360公斤/公顷,晚播期产量减少640公斤/公顷。对气象指标与籽粒数、籽粒产量和籽粒蛋白质进行了相关分析。PQ、PQvpd与粒数、产量呈极显著正相关。Tmean、Tmax、T30和VPD与粒数和产量呈极显著负相关。籽粒蛋白质含量与最高气温呈显著正相关,与天气指数PQ和PQvpd呈显著负相关。PQ和PQvpd可以用来预测籽粒数和籽粒产量潜力。结果表明,利用PQ和PQvpd预测籽粒数和籽粒产量比单独利用温度和辐射预测籽粒数和籽粒产量更可靠。
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引用次数: 0
A statistical method to standardize and interpret the activity data generated by wireless biosensors in dairy cows 一种用于标准化和解释奶牛无线生物传感器产生的活动数据的统计方法
Pub Date : 2023-11-23 DOI: 10.1017/s0021859623000576
Wang-Hee Lee, Mingyung Lee, Dae-Hyun Lee, Jae-Min Jung, Hyunjin Cho, Seongwon Seo
Activity biosensors have been used recently to measure and diagnose the physiological status of dairy cows. However, owing to the variety of commercialized activity biosensors available in the market, activity data generated by a biosensor need to be standardized to predict the status of an animal and make relevant decisions. Hence, the objective of this study was to develop a standardization method for accommodating activity measurements from different sensors. Twelve Holstein dairy cows were monitored to collect 12 862 activity data from four types of sensors over five months. After confirming similar cyclic activity patterns from the sensors through correlation and regression analyses, the gamma distribution was employed to calculate the cumulative probability of the values of each biosensor. Then, the activity values were assigned to three levels (i.e., idle, normal and active) based on the defined proportion of each level, and the values at each level from the four sensors were compared. The results showed that the number of measurements belonging to the same level was similar, with less than a 10% difference at a specific threshold value. In addition, more than 87% of the heat alerts generated by the internal algorithm of three of the four biosensors could be assigned to the active level, suggesting that the current standardization method successfully integrated the activity measurements from different biosensors. The developed probability-based standardization method is expected to be applicable to other biosensors for livestock, which will lead to the development of models and solutions for precision livestock farming.
近年来,活性生物传感器已被用于奶牛生理状态的测量和诊断。然而,由于市场上可获得的商业化活动生物传感器种类繁多,生物传感器产生的活动数据需要标准化,以预测动物的状态并做出相关决策。因此,本研究的目的是开发一种标准化方法,以适应来自不同传感器的活动测量。对12头荷斯坦奶牛进行了为期5个月的监测,从4种类型的传感器收集了12 862个活动数据。在通过相关和回归分析确认传感器相似的循环活动模式后,采用伽马分布计算每个生物传感器值的累积概率。然后,根据每个级别的定义比例将活动值分配到三个级别(即空闲,正常和活动),并比较四个传感器在每个级别的值。结果表明,属于同一水平的测量数相似,在特定阈值下差异小于10%。此外,4个生物传感器中的3个内部算法产生的热警报中有87%以上可以被分配到活动水平,这表明目前的标准化方法成功地整合了来自不同生物传感器的活动测量。所开发的基于概率的标准化方法有望适用于其他牲畜生物传感器,这将导致精确畜牧业模型和解决方案的发展。
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引用次数: 0
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The Journal of Agricultural Science
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