Characteristics Of Production Systems Research Articles

Characterization of circulating miRNA in cow milk and colostrum.

MicroRNAs (miRNAs) are short RNA molecules, typically 21-25 nucleotides long, synthesized within eukaryotic cells. They play a crucial role in coordinating complex gene expression regulatory networks. The miRNAs are involved in post-transcriptional regulation, either by degrading target mRNA or suppressing their transcription, thereby influencing protein translation. Also, the variation of miRNAs expression in different milk components suggests diverse metabolic pathways. Additionally, characteristics of farm production systems exert a noticeable influence on miRNAs profiles, shaping the functional properties of bovine milk. In this study, milk and colostrum samples of Holstein cows (Bos taurus) were collected for RNA extraction and sequencing. Sequencing data underwent quality controls, and short non-coding RNA reads were analyzed to identify and compare miRNAs profiles. The sequencing runs yielded 73,567,661 and 44,283,978 reads for milk and colostrum samples, respectively. Following trimming, 8,335,860 and 7,778,212 reads for milk and colostrum samples were retained. A total of 4.3% milk and 37.8% colostrum reads were identified as miRNAs. Overall, 157 miRNAs were common to milk and colostrum, 2 were unique to milk, and 90 were unique to colostrum. After applying a minimal cutoff of 100 reads per miRNA, 146 miRNAs were considered as expressed. In milk, bta-miR-101 was unique; in colostrum, bta-miR-18a, bta-miR-262-3p, bta-miR-130a, and bta-miR-224 were unique; and 141 miRNAs were common to colostrum and milk. Chromosome distribution of these miRNAs varied, with higher representation on autosome 19 and sexual chromosome X. Overall, colostrum contained a greater number of miRNAs, although specific miRNAs such as miR-11-988b, miR-140, and miR-146b were more abundant in milk. Conversely, miRNAs such as miR-7a-5p, let-7e, and miR-16a were more prevalent in colostrum. Validation through qPCR confirmed the expression levels of selected miRNAs from RNA sequencing, establishing concordance between the methods. Analysis of gene regulation by specific miRNAs identified key miRNAs (e.g., miR-223, miR-181a, and miR-155) involved in regulating various genes. Distinct miRNAs profiles in milk and colostrum suggest various functionalities, potentially influencing calf development and immune responses. The study unveils a comprehensive map of miRNAs in milk and colostrum and highlights their potential roles in regulating biological processes, as they play an essential role in calf development, disease resistance, and metabolism.

Small ruminant farmers’ feeding strategies to cope with climate change across five agroecological zones of Benin, West Africa

This study aimed to understand feeding strategies used by small ruminant farmers to cope with climatic change in the five contrasting agroecological zones (AEZ) of the Benin Republic and to identify the determinants of adopting these strategies. A semi-structured questionnaire was used to conduct interviews with 400 smallholder farmers in the rural areas of Benin. Data was collected on production system characteristics, farmers’ perception of climatic changes' impacts on livestock production, and their coping strategies. Cross tabulations with Chi2 statistic and the non-parametric Kruskal Wallis test were used to compare farmers’ perceptions and coping strategies between the five AEZ. Then, the binomial logistic regression was used to identify determinants of using a particular adaptive feeding strategy. The farmers perceived climatic changes as rainfall delays, increasing rainfall, less frequent drought periods during the rainy season, no change in sunshine duration, and no change in temperature. These changes negatively affected grassland biomass production (86.3 %, 86.3 % and 77.5 % of farmers in South Borgou, Plateau, Atacora chain AEZ, respectively) and water availability (100 %, 93.7 %, and 85 % of farmers in Oueme Valley, Plateau and Mekrou-penjari AEZ, respectively). Consequently, farmers mentioned decreased animal growth (58.8 % and 45 % of farmers in Plateau and South Borgou AEZ, respectively) and increased animal mortalities (43.8 % in Plateau AEZ). Farmers' current and future coping strategies varied significantly (p<0.05) among AEZ. These strategies included more diversification of feed resources used, more free wandering of animals, feeding intensification with supplements as current strategies, and new feed resource exploration and forage cultivation as future strategies. Logistic regression results showed that gender, education level, main activity, and the climatic and agroecological zones where the farm is located influenced the strategies used. The study showed that farmers understood climate change and its impact on production systems. In response, the common climate-smart feeding strategies adopted were mainly diversifying feed resources. Feed resources use strategies, and limitations to adopting these strategies, could be assessed in future studies.

Unveiling the Nutritional Quality of Terrestrial Animal Source Foods by Species and Characteristics of Livestock Systems.

Background. It is well-established that a range of macronutrients, micronutrients and bioactive compounds found in animal-source foods play unique and important roles in human health as part of a healthy diet. Methods. This narrative review focuses on terrestrial animal source foods (TASFs). It particularly analyzes five groups: poultry eggs, milk, unprocessed meat, foods from hunting and wildlife farming, and insects. The objectives were as follows: (1) examine the nutrient composition of TASFs within and across livestock species, drawing on the country and regional food composition databases; (2) analyze the influence of intrinsic animal characteristics and production practices on TASF nutritional quality. Results. TASFs are rich in high-quality proteins and fats, as well as micronutrients such as vitamin B12, iron or zinc. This study found differences in the nutritional quality of TASFs by livestock species and animal products, as well as by characteristics of livestock production systems. Our findings suggest that there may be public health opportunities by diversifying TASF consumption across species and improving certain aspects of the production systems to provide products that are both more sustainable and of higher quality. Conclusions. Future research should adopt a more holistic approach to examining the food matrix and the dietary patterns that influence TASF digestibility. It is necessary to include meat from hunting and wildlife farming and insects in global food composition databases, as limited literature was found. In addition, scarce research focuses on low- and middle-income countries, highlighting the need for further exploration of TASF food composition analysis and how intrinsic animal characteristics and livestock production system characteristics impact their nutritional value.

Research on typical operating conditions of hydrogen production system with off-grid wind power considering the characteristics of proton exchange membrane electrolysis cell

Hydrogen energy, with its abundant reserves, green and low-carbon characteristic, high energy density, diverse sources, and wide applications, is gradually becoming an important carrier in the global energy transformation and development. In this paper, the off-grid wind power hydrogen production system is considered as the research object, and the operating characteristics of a proton exchange membrane (PEM) electrolysis cell, including underload, overload, variable load, and start- stop are analyzed. On this basis, the characteristic extraction of wind power output data after noise reduction is carried out, and then the self-organizing mapping neural network algorithm is used for clustering to extract typical wind power output scenarios and perform weight distribution based on the statistical probability. The trend and fluctuation components are superimposed to generate the typical operating conditions of an off-grid PEM electrolytic hydrogen production system. The historical output data of an actual wind farm are used for the case study, and the results confirm the feasibility of the method proposed in this study for obtaining the typical conditions of off-grid wind power hydrogen production. The results provide a basis for studying the dynamic operation characteristics of PEM electrolytic hydrogen production systems, and the performance degradation mechanism of PEM electrolysis cells under fluctuating inputs.

Carbon balance analysis of agricultural production systems in oasis areas

China is the biggest emitter of greenhouse gases (GHGs) in the world, and agricultural GHG emission accounts for nearly a fifth of the total emission in China. To understand the carbon absorption and emission characteristics of agricultural production systems in those arid oasis areas, a typical representative city in northwestern China, Zhangye City, was selected for study.The emission factor method was used to analyze and calculate the characteristics of changing carbon emission dynamics in the whole agricultural production system in Zhangye city region (38,592 km2) from 2010 to 2021.The results revealed that carbon emissions during agricultural planting mainly come from fertilizers, which account for the highest proportion (47.9%) of total carbon emissions in agricultural planting. Animal enteric fermentation emissions from local livestock farming are the main contributor (86%) to GHG emissions. The annual average carbon absorption intensity is 4.4 t C-eq ha−1 for crop and 2.6 t C-eq ha−1 for the agricultural production system. The ratio of total carbon emissions from agricultural production to carbon sequestration of crops is 1:1.7. We find that the total carbon sequestration slightly exceeds its total carbon emissions in the study region, with an annual average of 41% for its sustainable development index. Carbon emissions of the agricultural production system in this oasis area are mainly driven by the livestock industry, mostly CH4 emissions from cattle raising.Reducing the local carbon emissions from the livestock industry, typically the cattle raising, will play a crucial role in reducing carbon emissions from this local agricultural production system and maintaining its net positive carbon balance.

European Green Deal: Justification of the Relationships between the Functional Indicators of Bioenergy Production Systems Using Organic Residential Waste Based on the Analysis of the State of Theory and Practice

Based on the analysis conducted on the state of theory and practice, the expediency of assessing the relationships between the functional indicators of bioenergy production systems using the organic waste of residential areas is substantiated in the projects of the European Green Deal. It is based on the use of existing results published in scientific works, as well as on the use of methods of system analysis and mathematical modeling. The proposed approach avoids limitations associated with the one-sidedness of sources or subjectivity of data and also ensures complete consideration of various factors affecting the functional indicators of the bioenergy production system from the organic waste of residential areas. Four types of organic waste generated within the territory of residential areas are considered. In our work, we used passive experimental methods to collect data on the functional characteristics of bioenergy production systems, mathematical statistics methods to process and interpret trends in the functional characteristics of bioenergy production systems using municipal organic waste, and mathematical modeling methods to develop mathematical models that reflect the patterns of change in the functional characteristics of bioenergy production systems. The results indicate the presence of dependencies with close correlations. The resulting dependencies can be used to optimize processes and increase the efficiency of bioenergy production. It was found that: (1) yard waste has the highest volume of the total volume of solid organic substances but has a low yield of biogas and low share of methane production; (2) food waste has the highest yield of biogas and, accordingly, the highest share of methane production; (3) mixed organic waste has the lowest volume of the total volume of solid organic substances and the lowest content of volatile organic substances. The amount of electricity and thermal energy production varies by type of organic waste, with mixed organic waste having a higher average amount of electricity production compared to other types of waste. It was established that the production volume of the solid fraction (biofertilizer) is also different for different types of organic waste. Less solid fraction is produced from food waste than from yard waste. The obtained research results are of practical importance for the development of sustainable bioenergy production from organic waste in residential areas during the implementation of the European Green Deal projects. They provide further research on the development of effective models for determining the rational configuration of bioenergy production systems using organic waste for given characteristics of residential areas.

Numerical simulation and experimental verification of solar PVT coupled PEM electrolyzer system for hydrogen production

Hydrogen production by electrolysis of water is the key to the future of hydrogen fuel production. This study proposes a hydrogen production system based on the thermoelectric demand for proton exchange membrane electrolyzers (PEMEs) and the characteristics of the thermoelectric output of photovoltaic (PV) thermal (PVT) systems. The proposed system combines PVT and PEME to realize thermoelectric hydrogen–oxygen multiproduction and establishes and validates the thermoelectric coupled numerical model used for the prediction of the operating characteristics of the PVT-PEME system. Furthermore, it investigates and compares the irradiation intensity, ambient temperature, and inlet flow rate of the PVT-PEME and PV-PEME systems, and estimates the operating characteristics of the PVT-PEME system in different climates. The results show that the electrolyzer energy efficiency tends to increase and then decrease with increasing irradiation intensity; the PVT-PEME efficiency increases with increasing ambient temperature; and the PV-PEME efficiency decreases with increasing ambient temperature. Moreover, the efficiency of the electrolyzer decreases with an increase in the inlet flow rate, but the PVT-PEME efficiency increases. The high temperature inhibits the performance of PV modules, which is promoted in PEME after heat exchange in the PVT system, improving the operating efficiency. In addition, an evaluation of the actual operating characteristics of the PVT-PEME hydrogen production system in different climates indicates that the system operated for shorter and less efficient times when operating at cold and low irradiation intensities.

Typification and differentiation of smallholder dairy production systems in smallholder mixed farming in the highlands of southern Ethiopia.

The present study aimed to classify smallholder dairy production systems by analyzing land allocation for various crop types and characterizing them based on integration with specific crops which is gap in earlier studies. A total of 360 smallholder farmers were interviewed to generate firsthand information in addition to using secondary data sources. The classification utilized K-means clustering, while discriminant analysis was applied to accentuate the distinct characteristics of dairy production systems (DPSs). Subsequently, for a particular crop to be considered dominant, the minimum farmland allocation had to exceed 30%. Based on this, the 360 respondent farmers in the study areas were categorized into four distinct DPSs: diversified crop-based (DCB) at 31%, enset-based (EB) at 28%, cereal-based (CB) at 24% and cash crop-based (CCB) with coffee, khat, vegetables, fruits, and sugarcane accounting for 17%. Within the CCB dairy production system, where cash crops were cultivated most dominantly, averaging 56% of the farmland, farmers reported the highest annual income and, consequently, acquired more improved dairy cows, facilitating their entry into intensive dairy production. Ownership of improved dairy cattle breeds, use of agro-industrial byproducts as feed, practicing stall feeding and better housing are observed practices in this DPS that relate to the intensification of dairy production. This positive relationship was observed between the commercialization of crops and the intensification of dairy production in the CCB dairy production system. In the EB dairy system, enset dominates with a 33% area share, leading to increased residues for cattle feed. They keep large herds of local cattle, limited crossbreeding experience, and prefer conventional feeding. The CB system allocates 47% of land to cereals, justifying cereal residues as primary dairy feed. Cultivating grasses like Pennisetum pedicellatum and Phalaris arundinacea is also highly valued in the system. The DCB system, with diverse crops (none exceeding 30%), implies varied residues for dairy feed. These findings reveal unique characteristics across dairy systems, indicating a positive correlation between crop commercialization and dairy intensification. Hence, understanding each type of DPS and its characteristics will help development experts or those in charge of designing agricultural policy to establish the best strategic plans for enhancing the productivity of dairy cattle under smallholder conditions.

Product and production design - Rethinking views on flexibility

The recent years have shown that long global supply chains are vulnerable considering volatile markets. As a result, efforts to achieve supply chain resilience are increasing. Achieving resilience requires flexibility, incorporated in product development, which can be implemented by the production system. Flexibility also offers the advantage in the context of sustainability that production facilities remain in use longer than rigid production lines because they can be better retrofitted. Furthermore, volatile markets challenge companies with a higher frequency of changes of requirements and decreasing forecast quality. Accompanied by a decreasing time-to-market and higher complexity of products companies need to increase their overall flexibility. A particular challenge is that routing flexibility is not used in production, for example, because the control effort is too time-consuming and complex. The use of AI and cyber-physical systems provides support to manage the control effort and thus enable flexibility in production. This paper discusses the role of flexibility in product development and production planning. The characteristics of products and production systems are analysed to identify important design aspects for flexibility. Comparing different systems shows for instance that non-linear structures with flexible links offer strategic advantages.

Participatory investigation of goat farmers' breeding practices, trait preference, and selection criteria in Burkina Faso.

The community-based breeding program (CBBP) is an innovative approach recommended for genetic improvement and sustainable use of animal genetic resources in extensive farming systems. Successful implementation of this approach requires an understanding of the characteristics of production systems, breeding objectives, and farmers' trait preference. This study aimed to identify the selection criteria of goat farmers in rural areas of Burkina Faso and their potential implications in establishing CBBP. Following focus group discussions, a well-structured questionnaire was designed and administered to 372 randomly selected goat farmers in two different agro-ecological zones. A list of traits obtained during focus group discussions was provided to farmers individually, and they were asked to rank the ones they preferentially use to select breeding animals. Statistical tests were conducted to compare data between the two agro-ecological zones. The results showed that the average goat flock per household was higher (P < 0.05) in the Sudanian (15.68 ± 13.76), compared to the Sudano-Sahelian area (12.93 ± 13.3). Adult females were the dominant age-sex group in both areas. Reasons for culling, keeping breeding bucks, and castration practice were significantly different (P < 0.05) among agro-ecological zones. The most important common criterion for selection in the two zones was body size, coat color, and growth rate for the bucks and does, while fertility (0.06) parameters including twining ability (0.18), kidding frequency (0.11), and mothering ability (0.15) were furthermore considered for breeding does selection. These findings provide valuable insights for developing CBBPs tailored to goat production in the study areas.

The Strategy of Strengthening Efficiency and Environmental Performance of Product Changeover in the Multiproduct Production System

Product changeovers are especially critical for multiproduct environments where key production system requirements are flexibility, time, and quality. Massive waste of production time and environmental pollution increase with changeovers significantly. It is noted that the green supply chain is gradually emerging, and the environmental policies in countries are also increasing pressure on manufacturers globally. However, how to improve the changeovers’ environmental performance in manufacturing enterprise are not entirely focused. The present study aims to raise the changeovers’ time efficiency and reduce environmental pollution in the multiproduct production system. This paper first analyzes the characteristics of multiproduct production systems and the causes of inefficient work and pollution and then extracts the problems that need to be optimized. They are the frequent changeover work, complex operation programs, and load imbalance. Multiproduct Production Fast Changeover (MPFC) is developed based on these problems, which integrates the Analytic Hierarchy Process, Entropy Weight method, Divisive Analysis, and Firefly algorithm. In addition, Divisive Analysis’s distance calculation is improved for flexible clustering targets. Firefly algorithm’s exploration, exploitation, and population coordination mechanisms have also been enhanced. The effectiveness of MPFC is proved in a real multiple flow-lines production case: time efficiency was increased, while the multiple industrial pollutions and key resource consumption were also reduced.

Intelligent safe operation and maintenance of oil and gas production systems: Connotations and key technologies

Oil and gas production systems have the characteristics of high operation and maintenance risk and great accident influence. With the deep integration of informationization and industrialization, the development direction and necessary choice of the oil and gas industry is to develop the oil and gas production system into the interconnected, multi-domain interactive cyber-physical intelligent system. In order to avoid or reduce the complex, diverse and potentially unknown safety risks in the process of oil and gas production, improve the safety and reliability of oil and gas production system and increase the production efficiency, this paper analyzes the safety problems occurring in the intelligentization process of oil and gas production system and constructs a system from the perspective of operation and maintenance based on key elements of intelligent safe operation and maintenance technology, combined with the typical production scenarios in the oil and gas production industry. And the following research results are obtained. First, the connotation of intelligent safe operation and maintenance technology is clarified, the key elements and existing problems and challenges of intelligent safe operation and maintenance technology are analyzed, and the “1-2-3-4-5-6” intelligent safe operation and maintenance technology system of oil and gas production system is constructed, which empowers six key technologies with key elements of oil and gas production to realize the essential safety of oil and gas production system. Second, the intelligent safe operation and maintenance technology actively promotes the application and implementation of condition monitoring, health management, risk assessment, intelligent early warning technologies in typical production scenarios such as drilling and extraction, storage and transportation, refining and chemical industry in up, middle and down streams of oil and gas production. Third, in view of the characteristics of oil and gas production system under digital transformation, it is proposed to develop the intelligent safe operation and maintenance technology with the functions of intelligent decision-making, active prevention and comprehensive safety in the future to help the safe construction in the field of oil and gas production and promote the safe and healthy development of the oil and gas industry. In conclusion, the research on intelligent safe operation and maintenance technology system of oil and gas production system is conducive to the safe construction in the field of oil and gas production, which will not only provide technical support for the realization of trouble-free oil and gas production system, but also provide reference for the intelligent development of the world oil and gas industry.

Drivers and frictions of workplace accidents: an empirical investigation of cross-country European heterogeneity

ABSTRACT This paper presents an empirical investigation on the determinants of workplace accidents across Europe and focuses on the extent to which production-system characteristics (employment sectoral risk, size of firms, temporary contracts), business cycle and socio-economic factors (GDP, level of investments, unemployment, education) and other territorial controls (crime index) might account for cross-country heterogeneity. We use Eurostat data, and our panel is composed of 27 European countries over the period 2010–2018. Implementing different functional forms and estimation methodologies (pooled OLS, panel fixed and random effects models, system-GMM and semiparametric fixed effects model), we find robust evidence that productive-system structural characteristics, business cycle controls and the other territorial variables are effective in explaining European cross-country heterogeneity. Moreover, we find evidence of a nonlinear relationship between GDP and occupational accidents.

Factors influencing concentrate feeding: dairy farmers' perceptions of dairy production system characteristics and market relations

This study aimed to investigate factors that influence the use of concentrate in dairy farms based on farmers' perceptions of dairy system characteristics and relationships with the dairy industry. Data were collected through questionnaires administered on-site to 155 dairy farmers in Paraná State, Brazil. Partial least squares structural equation modeling was used to analyze the data. Dairy farmers' perceptions were measured by the theoretical constructs, concentrate feeding, forage, genetics, management, and market. The results revealed that dairy farmers' decision to adopt concentrate feeding was mainly determined by the genetic construct (defined by herd genetics and breeding technology) and the market construct (defined by the ability of farmers to negotiate milk prices with the industry and the number of interested buyers). Concentrate feeding was also found to be influenced by farmers' perceptions of the management construct (management of costs and animal performance) and the forage construct (forage source and farmers' self-confidence in providing forage to cows throughout the year). These findings suggest that strategies aimed at stimulating concentrate feeding in dairy farms should focus on the following factors (listed in order of importance): genetic improvement, farmer–industry relations, financial and herd management, and forage supply and availability.

Electromechanical dynamic analysis for powertrain of off-grid switched-reluctance wind turbine hydrogen production system

Research on hydrogen production from wind power is important for improving wind energy utilization and hydrogen production efficiency; however, research on switched-reluctance hydrogen production from wind power has been relatively limited, and its system operation characteristics are unclear. Therefore, it is necessary to conduct research on the electromechanical coupling characteristics of switched-reluctance wind turbine hydrogen production systems (WTHPSs). An electromechanical dynamic model was established for the powertrain of an off-grid switched-reluctance WTHPS, including wind turbine, gear transmission system, switched-reluctance generator (SRG), and hydrogen production devices (HPDs). The model considers the detailed characteristics of the gear system, the nonlinear physical details of the HPD, and the electromagnetic characteristics of the generator. An improved control strategy was also developed for the SRG to reduce torque fluctuation. The steady- and transient-state electromechanical characteristics were simulated and analyzed, and the influences of the SRG control strategy and HPD switching on the system dynamic characteristics and hydrogen production rate were investigated. First, with respect to the improved SRG control strategy, the results show that SRG torque fluctuation can be reduced. The influence of the SRG electromagnetic torque on the transmission system gradually decreases from the high-speed stage to the low-speed stage. However, for a sudden decrease in wind speed, the SRG with the improved control strategy tracks the reference speed more slowly. Second, with respect to the hydrogen production rate, almost no difference can be observed between the two SRG control strategies. Single and multiple HPDs have a slight effect on the dynamic characteristics of the system when the HPDs can consume all the generated power. The production rate of HPDs in a parallel connection is higher than that with a single device at the same power, and the difference increases with an increase in power.

Soil Census of Kentucky High Tunnels Reveals Statewide Distribution of Two Meloidogyne Species

High tunnels are passively heated and cooled structures used for specialty crop production that can increase marketable yields, extend the growing season, and protect crops from harsh weather. Kentucky has more than 1,500 high tunnels, and although there are many benefits, production still has several challenges. High soil temperatures, lack of rotation and sanitation, and intensive and continuous cropping make high tunnels hospitable environments for the root-knot nematode (RKN; Meloidogyne spp.). This plant parasite infects roots, causing chlorosis, wilting, stunting, and yield loss. Determining the presence, population density, and species of RKN is important to inform management strategies. To our knowledge, this is the first research aimed at determining the presence and distribution of RKN across Kentucky. From 2019 to 2022, we sampled the soil in 175 high tunnels in 62 counties. The characteristics of production system, soil type, crop rotation, and high tunnel age were collected to analyze with RKN presence, species, and soil population density. Of the soil samples collected, 45% had no presence of RKN. Among those samples where RKNs were observed, 55% were identified as M. incognita, 39% as M. hapla, and 4% as M. arenaria. RKN presence was dependent on production system and crop rotation, whereas RKN species was dependent on production system and soil type. With over half of the sampled high tunnels infested with RKN, this project justifies further research for management strategies for RKN, especially those that are sustainable species-specific options and appropriate for commercial high tunnels.

A Study on the Postposition of “Original Lao Qi Da”

This article tries to study the characteristics of the postposition system of Original Lao Qi Da from the perspective of the contact between Chinese and Mongolian, By comparing it with modern Chinese Mandarin and the Ganqing dialects that are also influenced by the Altaic language, this paper conducts a comprehensive analysis of the characteristics, usage and formation motivation of the postposition system in Original Lao Qi Da from the perspective of language contact. The language contact level of Original Lao Qi Da with Mongolian is relatively not too deep. It is mainly produced by literal translation of semantically related words and Mongolian through the process of “grammar borrowing”, which is not finalized and completely digested. It is similar to the northwest dialect, but there are obvious differences in the production mechanism and system characteristics.

69 Animal Sourced Foods Role in Sustainable Nutrition

Abstract Amid growing concern regarding the food system are calls to reduce or eliminate animal sourced foods (ASF) from human diets. Despite the green revolution and consequent increase in crop yields, nutrient deficiencies are still problematic, particularly in developing regions. In the US, ASF provide 24% of energy, 48% of protein, approximately 50% of the essential amino acids and essential fatty acids as well as the micronutrients (White and Hall, 2017). This presentation introduces a framework for evaluation and discusses remaining knowledge gaps regarding the role of ASF in sustainable food systems that provide nutritious diets. Lifecycle assessment (LCA) was used to provide an accounting of environmental and sustainability characteristics of food production systems. LCA has an explicit goal the identification of tradeoffs between stages in the supply chain and tradeoffs across environmental dimensions. In a published study (Kim et al., 2020) using a hybrid lifecycle assessment technique, it was shown that while vegetarian diets resulted in lower environmental impacts across several environmental categories, that the US non-vegetarian recommended dietary guidelines led to increases for many categories. This is driven by the increased consumption of less calorically dense foods and changes in the patterns of food loss and waste. Ongoing studies of US beef production systems are providing insight into factors behind the variability in sustainability driven by practice and location. One management practice receiving attention is Adaptively Managed Paddocks (AMP). Sequestration estimates were combined with process model simulations of cow calf finishing operations. One system used conventional grain finishing and the other used grass finishing. The potential mitigation of GHG emissions from the potential sequestration is significant. Complete assessment of the role of ASF in healthy diets from sustainable food systems requires a full understanding of the benefits and costs of alternatives and informed decisions based on understanding of tradeoffs.

140 Redefining gut Barrier Function for Beef and Dairy Cattle

Abstract Of the many roles that the gastrointestinal tract (GIT) must facilitate, coordinated regulation of molecule movement across the gastrointestinal is key. This coordinated regulation allows for nutrient absorption while limiting permeation of non-desired molecules and is referred to as barrier function. Barrier function of the GIT includes intrinsic, extrinsic, and immunological factors, but generally permeability assessments are conducted to evaluate the whole-animal response and most studies focus on the extrinsic components of GIT barrier function. Common approaches to evaluate GIT permeability include the use of inert external markers varying in size and their measurement in blood or urine. Methodology exists for ex vivo, in vitro, and in vivo assessment; however, only in ex vivo and in vitro methods currently allow regionally specific information. Moreover, ex vivo studies have been essential to further elucidate factors that affect permeability such as osmolality, pH, and bioactive components such as histamine and lipopolysaccharides. For ruminants, extensive microbial degradation challenges the use of fermentable substrates as markers when assessing permeability and there is interest to compartmentalize permeability by region of the GIT. Recent research using dual markers to allow for total GIT and post-ruminal permeability have highlighted that regional permeability responses may be affected by production system, environmental conditions, and dietary characteristics. Future research is needed to improve the understanding of factors that affect GIT permeability, the regions involved, and strategies to support regulation of permeability.

Economic, social, and environmental assessment of farming Nile tilapia in net-cages in a reservoir in hot semi-arid region during an extended drought event.

Water reservoirs have been constructed in hot semi-arid regions, which may be used to produce fish. The present study described major features of the economic, social, and environmental characteristics of a net-cage Nile tilapia production system, stocked with 100 and 120 fish/m3, implemented in a reservoir in the hot semi-arid region of Brazil during an extended drought event. The production cycle was reduced from 6-8 to 4 months because of the lack of water in the reservoir. This resulted in the harvest of small fish weighting ~300-350 g that reached a low value in the market. As a consequence, indicators of financial feasibility showed low values, which were not attractive for entrepreneurs. Nevertheless, for both stocking densities, the monthly income was about US$ 1,500.00, which is 5-fold the minimum wage in the region. In general, the activity has a positive social impact, despite the low contribution to development of the local economy and food security because most supply came from outside and fish were sold to distant regions. Various age and ethnic groups were represented among the employees, but the enterprise was operated only by men. Phosphorus accumulations in the reservoir were 2.1 and 2.0 kg/t of fish produced and particulate material accumulations of 110 and 100 kg/t of fish production for 125 fish/m3 and 100 fish/m3, respectively. The study indicated that the Nile tilapia culture in hot semi-arid region is strongly affected by long drought events and adaptations in the planning and management should be done when implementing the systems. However, it seems that the activity has some resilience to still provide food, generate wealth, and promote social development for local population with low environmental impact.