Livestock and climate change: impact of livestock on climate and mitigation strategies

Suitable fermentation temperature of forage sorghum silage increases greenhouse gas production: Exploring the relationship between temperature, microbial community, and gas production

Silage is an excellent method of feed preservation; however, carbon dioxide, methane and nitrous oxide produced during fermentation are significant sources of agricultural greenhouse gases. Therefore, determining a specific production method is crucial for reducing global warming. The effects of four temperatures (10 °C, 20 °C, 30 °C, and 40 °C) on silage quality, greenhouse gas yield and microbial community composition of forage sorghum were investigated. At 20 °C and 30 °C, the silage has a lower pH value and a higher lactic acid content, resulting in higher silage quality and higher total gas production. In the first five days of ensiling, there was a significant increase in the production of carbon dioxide, methane, and nitrous oxide. After that, the output remained relatively stable, and their production at 20 °C and 30 °C was significantly higher than that at 10 °C and 40 °C. Firmicutes and Proteobacteria were the predominant silage microorganisms at the phylum level. Under the treatment of 20 °C, 30 °C, and 40 °C, Lactobacillus had already dominated on the second day of silage. However, low temperatures under 10 °C slowed down the microbial community succession, allowing, bad microorganisms such as Chryseobacterium, Pantoea and Pseudomonas dominate the fermentation, in the early stage of ensiling, which also resulted in the highest bacterial network complexity. According to random forest and structural equation model analysis, the production of carbon dioxide, methane and nitrous oxide is mainly affected by microorganisms such as Lactobacillus, Klebsiella and Enterobacter, and temperature influences the activity of these microorganisms to mediate gas production in silage. This study helps reveal the relationship between temperature, microbial community and greenhouse gas production during silage fermentation, providing a reference for clean silage fermentation.

The DairyPrint Model: A Decision-Support Model to Help Dairy Farmers and Other Stakeholders Towards Improved Sustainability

Dairy farmers face increasing pressure to reduce greenhouse gas (GHG) emissions [i.e., carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O)], but measuring on-farm GHG emissions directly is costly or impractical. Therefore, the dairy industry has relied upon mathematical models to estimate those emissions. However, current models tend to be not user-friendly, difficult to access or sometimes very research-focused, limiting their practical use. To address this, we introduce the DairyPrint model, a user-friendly tool designed to estimate GHG emissions from dairy farming. The model integrates herd dynamics, manure management, crop, and feed costs considerations, simplifying the estimation process while providing comprehensive insights. The herd module simulates monthly herd dynamics based on inputs as total cows, calving interval, and culling rate, outputting average annual demographics and estimating various animal related variables (i.e., dry matter intake, milk yield, manure excretion, and enteric CH4 emissions). These outputs feed into other modules, such as the manure module, which calculates emissions based on manure, weather data, and facility type. The manure module processes manure according to farm practices, and the crop module accounts for GHG emissions from manure, fertilizers, and limestone application, also estimating nutrient balances. The DairyPrint model was developed using the Shiny framework and the Golem package for robust production-grade shiny applications in the R programming language. We evaluated the model across 32 simulation scenarios by combining various factors and considering a standard free-stall system with 1000 dairy cows averaging 40 kg/day of milk production. These factors included 2 levels of NDF-ADF in the diet (28-22.8% and 24-19.5%), the presence or absence of 3-NOP dietary addition (yes or no) at an average dose of 70 mg/kg DM per cow daily, the type of bedding used (sawdust or sand), the frequency of manure pond emptying [once (only Fall) or twice a year (Fall and Spring)], and the utilization or non-utilization of a biodigester plus solid-liquid separator (Biod + SL). In our results across the 32 scenarios simulated, the average GHG emission was 0.811 kgCO2eq/kg of milk corrected for fat and protein contents (4% and 3.3%, respectively), ranging from 0.644 to 1.082. Notably, the scenario yielding the lowest GHG emission (i.e., 0.644 kgCO2eq/kg) involved a combination of factors, including a lower level of NDF-ADF in the diet in addition to incorporation of 3-NOP, utilization of sand as bedding, application of Biod + SL, and strategic manure pond emptying in both Fall and Spring. Conversely, the scenario that resulted in the highest GHG emission (i.e., 1.082 kgCO2eq/kg) involved a combination of higher level of NDF-ADF in the diet and excluded the incorporation of 3-NOP, utilization of sawdust as bedding, no application of Biod + SL, and manure pond emptying only in Fall. All these scenarios can be easily simulated in the DairyPrint model and results obtained immediately for user evaluation. Therefore, the DairyPrint model can help farmers move toward improved sustainability, providing a user-friendly and intuitive graphical user interface allowing the user to ask what-if questions.

Local and Global Public Health and Emissions from Concentrated Animal Feeding Operations in the USA: A Scoping Review

Up to 1.6 million tons of waste is produced annually by each of more than 21,000 concentrated animal feeding operations (CAFOs) located in the United States (USA). These operations give rise to externalities, including adverse local and global health impacts from CAFO waste emissions, which can potentially outweigh their economic viability. However, a shortage of evidence synthesis research exclusively on the impacts of USA-based CAFO waste emissions may hinder effective policy development. This scoping review (ScR) study, adhering to the guidelines from the Joanna Briggs Institute, conducted a search in databases including Scopus, Web of Science, PubMed, and Embase in May 2020, resulting in ten publications that met the inclusion criteria. The results suggest possible exposure of CAFO workers to multidrug-resistant Staphylococcus aureus (MDRSA), campylobacteriosis, and cryptosporidiosis. Communities near CAFOs experienced higher rates of adverse health impacts compared to those in non-CAFO areas, with patterns suggesting that proximity may correlate with increased odds of detrimental health effects. Implicit global health threats include methicillin-resistant Staphylococcus aureus (MRSA), MDRSA, campylobacteriosis, tuberculosis, and cryptosporidiosis. These studies provide foundational insights into CAFO proximity, density patterns, and adverse public health effects, indicating a need for evidence-informed environmental health policies to minimize local and global risks.

Cleaner anaerobic fermentation and greenhouse gas reduction of crop straw

Rice anaerobic fermentation is a significant source of greenhouse gas (GHG) emissions, and in order to efficiently utilize crop residue resources to reduce GHG emissions, rice straw anaerobic fermentation was regulated using lactic acid bacteria (LAB) inoculants (FG1 and TH14), grass medium (GM) to culture LAB, and Acremonim cellulolyticus (AC). Microbial community, GHG emission, dry matter (DM) loss, and anaerobic fermentation were analyzed using PacBio single-molecule real-time and anaerobic fermentation system. The epiphytic microbial diversity of fresh rice straw was extremely rich and contained certain nutrients and minerals. During ensiling, large amounts of GHG such as carbon dioxide are produced due to plant respiration, enzymatic hydrolysis reactions, and proliferation of aerobic bacteria, resulting in energy and DM loss. Addition of FG1, TH14, and AC alone improved anaerobic fermentation by decreasing pH and ammonia nitrogen content (P < 0.05) and increased lactic acid content (P < 0.05) when compared to the control, and GM showed the same additive effect as LAB inoculants. Microbial additives formed a co-occurrence microbial network system dominated by LAB, enhanced the biosynthesis of secondary metabolites, diversified the microbial metabolic environment and carbohydrate metabolic pathways, weakened the amino acid metabolic pathways, and made the anaerobic fermentation cleaner. This study is of great significance for the effective utilization of crop straw resources, the promotion of sustainable livestock production, and the reduction of GHG emissions.IMPORTANCETo effectively utilize crop by-product resources, we applied microbial additives to silage fermentation of fresh rice straw. Fresh rice straw is extremely rich in microbial diversity, which was significantly reduced after silage fermentation, and its nutrients were well preserved. Silage fermentation was improved by microbial additives, where the combination of cellulase and lactic acid bacteria acted as enzyme-bacteria synergists to promote lactic acid fermentation and inhibit the proliferation of harmful bacteria, such as protein degradation and gas production, thereby reducing GHG emissions and DM losses. The microbial additives accelerated the formation of a symbiotic microbial network system dominated by lactic acid bacteria, which regulated silage fermentation and improved microbial metabolic pathways for carbohydrates and amino acids, as well as biosynthesis of secondary metabolites.

Greenhouse gas emissions in the Indian agriculture sector and mitigation by best management practices and smart farming technologies-a review

The growing demand for agricultural products, driven by the Green Revolution, has led to a significant increase in food production. However, the demand is surpassing production, making food security a major concern, especially under climatic variation. The Indian agriculture sector is highly vulnerable to extreme rainfall, drought, pests, and diseases in the present climate change scenario. Nonetheless, the key agriculture sub-sectors such as livestock, rice cultivation, and biomass burning also significantly contribute to greenhouse gas (GHG) emissions, a driver of global climate change. Agriculture activities alone account for 10-12% of global GHG emissions. India is an agrarian economy and a hub for global food production, which is met by intensive agricultural inputs leading to the deterioration of natural resources. It further contributes to 14% of the country's total GHG emissions. Identifying the drivers and best mitigation strategies in the sector is thus crucial for rigorous GHG mitigation. Therefore, this review aims to identify and expound the key drivers of GHG emissions in Indian agriculture and present the best strategies available in the existing literature. This will help the scientific community, policymakers, and stakeholders to evaluate the current agricultural practices and uphold the best approach available. We also discussed the socio-economic, and environmental implications to understand the impacts that may arise from intensive agriculture. Finally, we examined the current national climate policies, areas for further research, and policy amendments to help bridge the knowledge gap among researchers, policymakers, and the public in the national interest toward GHG reduction goals.

The impacts of animal agriculture on One Health-Bacterial zoonosis, antimicrobial resistance, and beyond

The industrialization of animal agriculture has undoubtedly contributed to the improvement of human well-being by increasing the efficiency of food animal production. At the same time, it has also drastically impacted the natural environment and human society. The One Health initiative emphasizes the interdependency of the health of ecosystems, animals, and humans. In this paper, we discuss some of the most profound consequences of animal agriculture practices from a One Health perspective. More specifically, we focus on impacts to host-microbe interactions by elaborating on how modern animal agriculture affects zoonotic infections, specifically those of bacterial origin, and the concomitant emergence of antimicrobial resistance (AMR). A key question underlying these deeply interconnected issues is how to better prevent, monitor, and manage infections in animal agriculture. To address this, we outline approaches to mitigate the impacts of agricultural bacterial zoonoses and AMR, including the development of novel treatments as well as non-drug approaches comprising integrated surveillance programs and policy and education regarding agricultural practices and antimicrobial stewardship. Finally, we touch upon additional major environmental and health factors impacted by animal agriculture within the One Health context, including animal welfare, food security, food safety, and climate change. Charting how these issues are interwoven to comprise the complex web of animal agriculture's broad impacts on One Health will allow for the development of concerted, multidisciplinary interventions which are truly necessary to tackle these issues from a One Health perspective.

Development strategy of non-GMO organism for increased hemoproteins in Corynebacterium glutamicum: a growth-acceleration-targeted evolution

Heme, found in hemoproteins, is a valuable source of iron, an essential mineral. The need for an alternative hemoprotein source has emerged due to the inherent risks of large-scale livestock farming and animal proteins. Corynebacterium glutamicum, regarded for Qualified Presumption of Safety or Generally Recognized as Safe, can biosynthesize hemoproteins. C. glutamicum single-cell protein (SCP) can be a valuable alternative hemoprotein for supplying heme iron without adversely affecting blood fat levels. We constructed the chemostat culture system to increase hemoprotein content in C. glutamicum SCP. Through adaptive evolution, hemoprotein levels could be naturally increased to address oxidative stress resulting from enhanced growth rate. In addition, we used several specific plasmids containing growth-accelerating genes and the hemA promoter to expedite the evolutionary process. Following chemostat culture for 15 days, the plasmid in selected descendants was cured. The evolved strains showed improved specific growth rates from 0.59 h-1 to 0.62 h-1, 20% enhanced resistance to oxidative stress, and increased heme concentration from 12.95 µg/g-DCW to 14.22-15.24 µg/g-DCW. Notably, the putative peptidyl-tRNA hydrolase-based evolved strain manifested the most significant increase (30%) of hemoproteins. This is the first report presenting the potential of a growth-acceleration-targeted evolution (GATE) strategy for developing non-GMO industrial strains with increased bio-product productivity.

The impact of slaughter weight and sex on the carbon footprint of pig feed intake

The impact of pork production on global livestock's greenhouse gas emissions is substantial. Understanding the factors influencing these emissions is crucial in achieving a more sustainable pig husbandry. In two independent experiments, the impact of slaughter weight on the carbon footprint (CFP) of pig feed intake (CFPFI) was evaluated for growing-finishing pigs of different sexes (entire males (EM), barrows (BA), immunocastrates (IC) and gilts (GI)). In experiment 1 118 animals were raised individually in experimental conditions. In experiment 2 384 animals were housed in group (four pigs per pen), in controlled commercial farm circumstances. All animals were fed ad libitum in a three-phase feeding regime and slaughtered at different BW, ranging from 110 to 148 kg (experiment 1) and from 99 to 138 kg (experiment 2). When only the fattening period was considered, the CFPFI was expressed per kg carcass growth. When the production of piglets was also taken into account, the CFPFI was calculated per kg carcass weight. For all sexes, the heavier the pig, the higher the CFPFI per kg carcass growth (P < 0.05, experiment 1; P < 0.001, experiment 2) and per kg carcass weight (P < 0.05, experiment 1; P < 0.01, experiment 2). In addition, BA had a significantly higher CFPFI per kg carcass growth and per kg carcass weight compared to EM and IC and to EM, IC and GI in respectively experiments 1 and 2 (P < 0.001). When performing a desk study with a soy-free (i.e. reduced CFP) feed in the third phase of experiment 2, slaughter weight no longer affected the CFPFI per kg carcass growth (P = 0.133) and per kg carcass weight (P = 0.856). A higher slaughter weight thus implies a lower sustainability, unless a sufficiently low-CFP feed is provided in the finisher phase.

Multi-omics analyses reveal rumen microbes and secondary metabolites that are unique to livestock species

Ruminant livestock, including cattle, sheep, goats, and camels, possess a distinctive digestive system with complex microbiota communities critical for feed conversion and secondary metabolite production, including greenhouse gases. Yet, there is limited knowledge regarding the diversity of rumen microbes and metabolites benefiting livestock physiology, productivity, climate impact, and defense mechanisms across ruminant species. In this study, we utilized metataxonomics and metabolomics data from four evolutionarily distinct livestock species, which had fed on diverse plant materials like grass, shrubs, and acacia trees, to uncover the unique signature microbes and secondary metabolites. We established the presence of a distinctive anaerobic fungus called Oontomyces in camels, while cattle exhibited a higher prevalence of unique microbes like Psychrobacter, Anaeromyces, Cyllamyces, and Orpinomyces. Goats hosted Cleistothelebolus, and Liebetanzomyces was unique to sheep. Furthermore, we identified a set of conserved core microbes, including Prevotella, Rickenellaceae, Cladosporium, and Pecoramyces, present in all the ruminants, irrespective of host genetics and dietary composition. This underscores their indispensable role in maintaining crucial physiological functions. Regarding secondary metabolites, camel's rumen is rich in organic acids, goat's rumen is rich in alcohols and hydrocarbons, sheep's rumen is rich in indoles, and cattle's rumen is rich in sesquiterpenes. Additionally, linalool propionate and terpinolene were uniquely found in sheep rumen, while valencene was exclusive to cattle. This may suggest the existence of species-specific microbes and metabolites that require host rumen-microbes' environment balance. These results have implications for manipulating the rumen environment to target specific microbes and secondary metabolite networks, thereby enhancing livestock productivity, resilience, reducing susceptibility to vectors, and environmentally preferred livestock husbandry.IMPORTANCERumen fermentation, which depends on feed components and rumen microbes, plays a crucial role in feed conversion and the production of various metabolites important for the physiological functions, health, and environmental smartness of ruminant livestock, in addition to providing food for humans. However, given the complexity and variation of the rumen ecosystem and feed of these various livestock species, combined with inter-individual differences between gut microbial communities, how they influence the rumen secondary metabolites remains elusive. Using metagenomics and metabolomics approaches, we show that each livestock species has a signature microbe(s) and secondary metabolites. These findings may contribute toward understanding the rumen ecosystem, microbiome and metabolite networks, which may provide a gateway to manipulating rumen ecosystem pathways toward making livestock production efficient, sustainable, and environmentally friendly.

Design thinking for engaged learning in animal science: lessons from five semesters of a senior capstone course

This study presents a design-based research approach involving five iterations (semester) of implementing design thinking for engaged learning (DTEL) in an animal science capstone course. DTEL scaffolds design thinking into 10 stages for collaborative project-based learning to foster skills like problem solving and teamwork. Across five semesters (spring 2021 to spring 2023), student reflections (n = 276) were analyzed to identify aspects that worked well or were challenging. Network analysis visualized relationships (P < 0.05; Q > 0.4) between codes representing strengths, struggles, and alignment with principles from learning theories. Utilizing the relationships between strengths and theory-based principles to address struggles, resulted in changes to the design of the capstone course each iteration (time that the course was taught). The complexity of maps increased over iterations. Initially, struggles were prominent but decreased as responsive design refinements were made. Alignment of student experiences with principles from learning theories grew substantially from the first iteration to the last (theory-related nodes representing 11.4% vs. 24.4% in each network map, respectively), with learning theories also occupying more central positions in the last map (iteration five) compared to earlier ones (iterations one through four). These changes suggest student experiences increasingly aligned with principles of cognitive constructivism, social constructivism, constructionism, situated learning, and transformative learning. Design principles derived from the five-iteration study include: (1) allocating most time to hands-on lab work vs. lecture, (2) designating a coordinator faculty, (3) scaffolding for instructors unfamiliar with DTEL, (4) emphasizing consistency in processes over grades, and (5) intentionally developing teamwork skills. The study demonstrates the value of design-based research for iteratively refining and studying learning experiences to foster critical skills for undergraduate students in animal science.

Climate change and dairy farming sustainability; a causal loop paradox and its mitigation scenario

It is arguable at this time whether climate change is a cause or effect of the disruption in dairy farming. Climate change drastically affects the productive performance of livestock, including milk and meat production, and this could be attributed to the deviation of energy resources towards adaptive mechanisms. However, livestock farming also contributes substantially to the existing greenhouse gas pool, which is the causal of the climate change. We gathered relevant information from the recent publication and reviewed it to elaborate on sustainable dairy farming management in a changing climatic scenario, and efforts are needed to gather this material to develop methods that could help to overcome the adversities associated with livestock industries. We summarize the intervention points to reverse these adversities, such as application of genetic technology, nutrition intervention, utilization of chemical inhibitors, immunization, and application of metagenomics, which may help to sustain farm animal production in the changing climate scenario.

Monomodular and multifunctional processive endocellulases: implications for swine nutrition and gut microbiome

Poor efficiency of dietary fibre utilization not only limits global pork production profit margin but also adversely affects utilization of various dietary nutrients. Poor efficiency of dietary nutrient utilization further leads to excessive excretion of swine manure nutrients and results in environmental impacts of emission of major greenhouse gases (GHG), odor, nitrate leaching and surface-water eutrophication. Emission of the major GHG from intensive pork production contributes to global warming and deteriorates heat stress to pigs in tropical and sub-tropical swine production. Exogenous fibre enzymes of various microbial cellulases, hemicellulases and pectinases have been well studied and used in swine production as the non-nutritive gut modifier feed enzyme additives in the past over two decades. These research efforts have aimed to improve growth performance, nutrient utilization, intestinal fermentation as well as gut physiology, microbiome and health via complementing the porcine gut symbiotic microbial fibrolytic activities towards dietary fibre degradation. The widely reported exogenous fibre enzymes include the singular use of respective cellulases, hemicellulases and pectinases as well as their multienzyme cocktails. The currently applied exogenous fibre enzymes are largely limited by their inconsistent in vivo efficacy likely due to their less defined enzyme stability and limited biochemical property. More recently characterized monomodular, multifunctional and processive endoglucanases have the potential to be more efficaciously used as the next-generation designer fibre biocatalysts. These newly emerging multifunctional and processive endoglucanases have the potential to unleash dietary fibre sugar constituents as metabolic fuels and prebiotics, to optimize gut microbiome, to maintain gut permeability and to enhance performance in pigs under a challenged environment as well as to parallelly unlock biomass to manufacture biofuels and biomaterials.

Effects of herd management decisions on dairy cow longevity, farm profitability, and emissions of enteric methane - a simulation study of milk and beef production

Sustainable dairy and beef production provides environmental, economic, and social values that can potentially be maximized by optimizing herd management strategies. The length of a dairy cow's life is affected by, and affects, all three pillars of sustainability. Longevity in dairy cows is multifactorial and strongly dependent on herd management. Despite genetic improvements, the average time of culling for Swedish cows has barely changed and is currently at 2.6 lactations. This culling rate requires a high number of replacement heifers, generating high rearing costs for farmers. This study evaluated different herd management strategies to improve cow longevity and assessed the effects on enteric methane (CH4) emissions from the herd and the profitability of milk production and beef production from the dairy cows and their offspring. The base scenario, an average Swedish Holstein herd of 100 cows, was compared with seven scenarios simulated using a stochastic herd simulation model (SimHerd). Two of these scenarios involved improved health and survival of cows in the herd, three involved improved reproduction, one considered the consequences of keeping all surplus heifers in the herd, and one considered maximizing the use of X-sorted dairy semen and inseminating the rest of the herd with unsorted beef semen, to avoid surplus replacement heifers. Improved fertility had the greatest effect in increasing the productive life per cow, to 3.8 years compared with 2.8 in the base scenario, allowed for more use of beef semen, reduced the number of replacement heifers, and generated the highest herd profit (€98 per cow-year higher than base scenario). Keeping all surplus heifers instead of producing beef × dairy cross calves decreased the number of productive years by 0.8 and reduced profit by €22 per cow-year. The profit was highly associated with costs related to replacement heifers. The highest beef output (3 369 kg per year more than base scenario) was achieved by keeping all heifers and culling a high share of dairy cows, but this scenario also generated much higher enteric CH4 emissions (+1 257 kg per year). Improving health, survival, or fertility reduced enteric CH4 emissions by 90-255 kg per year, while total yearly beef production ranged from 59 kg less to 556 kg more than in the base scenario. Reducing the number of replacement heifers needed by improving cow reproductive performance is thus key to increasing cow longevity and profitability, while reducing enteric CH4 emissions from the herd without compromising milk and meat production.

Plant-based meat substitute analysis using microextraction with deep eutectic solvent followed by LC-MS/MS to determine acrylamide, 5-hydroxymethylfurfural and furaneol

For the analysis of plant-based meat substitutes and the determination of Maillard reaction products such as acrylamide, 5-hydroxymethylfurfural and furaneol, a novel and effective procedure based on hydrophobic natural deep eutectic solvent and liquid chromatography coupled with tandem mass spectrometry was developed for the first time. The 49 compositions of the deep eutectic solvents were designed and screened to select the most suitable option. The terpenoids eugenol and thymol in a molar ratio of 2:1 were selected as precursors for solvent formation, allowing effective extraction of the target analytes. The developed procedure comprised two main steps: extraction - in which the analytes are isolated from the solid sample due to the salting-out effect and pre-concentrated in the deep eutectic solvent, and back-extraction - in which the analytes are re-extracted into the formic acid solution for subsequent mass spectrometric detection. As the density of the aqueous phases changed during the extraction and back-extraction steps, the phenomenon of inversion of the coalesced organic phase was observed, which simplified the withdrawing of the phases. The linear range was 1-50 ng/mL for acrylamide, 10-1000 ng/mL for 5-hydroxymethylfurfural and 200-1000 ng/mL for furaneol with coefficients of determination above 0.9952. The developed method was fully validated and found recoveries were in the range 83-120%, with CVs not exceeding 4.9%. The method was applied to real sample analysis of pea-based meat substitutes.

Ammonia and greenhouse gas emissions from beef feedlot surface material treated with aluminum sulfate (alum) or microbial amendments

A lab-scale study evaluated ammonia (NH3 ) and greenhouse gases, emissions when aluminum sulfate (alum) or a microbial product were added to beef feedlot surface material (FSM). Three kilograms of FSM and 1.5 kg of water were added to stainless steel pans (50 cm × 30 cm × 6.5 cm). Treatments included a control (no amendment), 450 g alum, or 0.5 g microbial product. The pans were placed in an environmental chamber that was maintained at 23°C and 50%-60% humidity. Emissions were measured three times weekly for 3 weeks. Ammonia, N2 O, and CH4 were lower (p < 0.01) from pans with amendments compared to the control pans; emissions from the FSM that received the microbial treatment were lower than the FSM treated with alum. Methane emissions were similar for the control and alum-treated FSM but lower (p < 0.01) for the FSM that was treated with the microbial product. Nitrate-N was lower, and NH4+ -N and total sulfur concentrations were higher in FSM treated with alum compared to no treatment or the microbial treatment (p < 0.01). Results indicate that both alum and microbial amendments have benefits in reducing emissions from the feedlot surface, with the microbial product providing additional reductions in emissions compared to the alum.

Investigating the effect of supplementing different levels of Isochrysis galbana on in vitro rumen fermentation parameters

This study aimed to investigate the effect of supplementing Isochrysis galbana (I. galbana) at levels of 0 (control), 1, 2, 3, 4, and 5 (g/100 g DM) of the diet on the gas production kinetics, methane production, rumen fermentation parameters, and relative microbial population in vitro. Supplementation of I. galbana at high level (5 g/100 g DM) caused a significant decrease in total gas production (p < 0.05). High supplementation rates (4 and 5 g/100 g DM) decreased CH4 production relative to the control by 18.4% and 23.2%, respectively. Although rumen ammonia nitrogen (N-NH3) and total volatile fatty acids (VFA) concentrations were affected by dietary treatments, but the VFA profile did not changed. The relative proportion of protozoa and methanogenic archaea as well as Anaerovibrio lipolytica, Prevotella spp., Ruminococcus flavefaciens, and Fibrobacter succinogenes were decreased significantly as a result of microalgae supplementation. However, the relative abundance of Ruminococcus albus, Butyrivibrio fibrisolvens and Selenomonas ruminantium were significantly increased (p < 0.05), related to the control group. As well, the pH was not affected by dietary treatments. It was concluded that I. galbana reduced in vitro CH4 production and methanogenic archaea that its worth to be investigated further in in vivo studies.

Legumes: A Vehicle for Transition to Sustainability

Legumes are an excellent source of protein and have been used in the human diet for centuries. Consumption of legumes has been linked to several health benefits, including a lower risk of cardiovascular diseases, type 2 diabetes mellitus, and certain types of cancer, while legumes' high fiber content promotes digestive health. Aside from the positive health benefits, one of the most significant advantages of legumes is the low environmental footprint of their cultivation. They can be grown in a variety of climates and soil types, and they require less water and fertilizer than other crops, making them a sustainable option for farmers. Thanks to their nutritional and physicochemical properties, they are widely used by the food industry since the growing popularity of plant-based diets and the increasing demand for alternatives to meat offers the opportunity to develop legume-based meat substitutes. As the use of legumes as a source of protein becomes widespread, new market opportunities could be created for farmers and food industries, while the reduction in healthcare costs could have a potential economic impact. Achieving widespread adoption of legumes as a sustainable source of protein requires coordinated efforts by individuals, governments, and the private sector. The objective of this narrative review is to present the benefits coming from legume consumption in terms of health and environmental sustainability, and underline the importance of promoting their inclusion in the daily dietary pattern as well as their use as functional ingredients and plant-based alternatives to animal products.

Assessing consumers' preferences for beef and lamb meat linked to wildfire prevention services

Meat from silvopastoral systems, due to its provision of numerous ecosystem services such as wildfire risk reduction in Mediterranean forests, can address societal growing demands for meat produced with lower environmental impacts. Differentiation of meat from these systems may contribute to their economic sustainability and hence to reverse their decline in the Mediterranean. This study investigated consumer preferences and willingness-to-pay (WTP) for beef and lamb meat from silvopastoral systems associated to the provision of wildfire prevention service and explored two alternative ways of labelling this service. Through a choice experiment survey considering type of pasture, length of grazing period, production distance and price, we gathered data from 1209 meat consumers in two Spanish cities. We considered forest grazing with a target purpose as a level in the type of pasture attribute and it was presented either as grazing to prevent wildfires or grazing to reduce biomass in two alternative versions of the valuation survey. The random parameter logit model revealed the highest preferences and WTP towards nearby production distances, followed by targeted grazing and forest grazing, while the length of grazing period was less relevant. No significant differences in consumers WTP were found between conveying targeted grazing either as fire prevention or biomass reduction. Our findings also suggest that consumers' preferences varied with location, attitudes towards local food and environmental role of grazing and consumption habits. Knowledge gathered in our work contributes to understand consumers perceptions on the beneficial environmental impacts of meat production.

Effects of environmental and housing system factors on ammonia and greenhouse gas emissions from cattle barns: A meta-analysis of a global data collation

This study provides a meta-analysis on the relationships between cattle barn CH4, NH3 and N2O emission rates and their key drivers (i.e., housing type, floor type, environmental conditions). Understanding these relationships is essential to reduce uncertainties in emission inventories and suggest targeted mitigation measures. The total number of daily emission rates included in the analysis was 139 for CH4, 293 for NH3 and 100 for N2O emissions. Emission rates in the database showed a large variation with 45-803.5 g/LU d-1 for CH4, 0.036-146.7 gN LU-1 d-1 for NH3, and 0.002-18 gN LU-1 d-1 for N2O emissions. Despite the high emission variability, significant effects were identified·NH3 showed positive correlation with air temperature; NH3 emissions differed between housing types but not between floor types·NH3 emissions from tied stalls were lower than the ones from cubicle housing regardless of the floor type. Additionally, NH3 emissions from loose housings were lower than the ones from cubicle housing·NH3 and N2O emission rates from temperate wet zones were lower than the ones from temperate dry zones. CH4 emission rates were affected by environmental factors only and not by housing and floor type, showing negative correlation with air temperature and humidity. The factors investigated can be suggested as ancillary variables and descriptors when cattle barn emissions are measured, in order to make best use of emission data. Country-specific data of these key drivers can be included into national inventories to adapt them to different agroecosystems and support targeted policies.

Sustainable animal production: exploring the benefits of sperm sexing technologies in addressing critical industry challenges

The sex of the animals is of paramount importance in many animal production systems. This is particularly evident in the production of milk or in breeding programs focused on the production of female animals. In some cases, slaughter or euthanasia of animals of the unwanted sex becomes the only solution, highlighting ethical and economic concerns. As global demand for food continues to rise, the importance of addressing these issues becomes more evident. Reproductive technologies, such as sperm sexing techniques, may hold the key to addressing both animal welfare and the sustainability of animal production. The use of semen enriched with sperm capable of producing offspring of the desired sex can serve as a valuable tool for producers to exert greater control over production outcomes, not only helping to mitigate welfare issues related to the unnecessary premature death of unwanted offspring but also providing a possible ally in the face of stricter animal welfare guidelines. In addition, sexed semen can also contribute to financial gains and reduce greenhouse gas emissions and food waste associated with the less profitable part of the herd. This paper explores the positive impacts that sperm sexing can have on animal welfare, economy, and environment. It also discusses currently available options and strategies for more successful implementation of sexed semen. Partnerships between companies and scientists will be essential to find innovative ways to adapt current production systems and develop sperm sexing technologies that apply to most livestock industries.

Innovative Applications of Tenebrio molitor Larvae in Food Product Development: A Comprehensive Review

The utilization of alternative and sustainable food sources has garnered significant interest as a means to address the challenges of food security and environmental sustainability. Tenebrio molitor larvae, commonly known as mealworms, have emerged as a promising candidate in this context, as they are a rich source of nutrients and can be reared with relatively low resource input. This review article presents an in-depth analysis of the diverse range of food products developed using T. molitor larvae and the distinctive properties they bestow on these products. The review encompasses an exploration of the nutritional composition of the larvae, emphasizing their rich protein content, balanced amino acid profile, fatty acids with health benefits, vitamins, and minerals. It delves into how these attributes have been harnessed to enhance the nutritional value of a variety of food items, ranging from protein-rich snacks and energy bars to pasta, bakery goods, etc. Each of these applications is discussed with regard to how T. molitor larvae contribute to the nutritional content and sensory characteristics of the final product. Furthermore, this review sheds light on the innovative techniques and processing methods employed to incorporate T. molitor larvae into different food matrices. It addresses challenges related to taste, texture, and appearance that have been encountered and the strategies devised to overcome related problems. Overall, this comprehensive review elucidates the diverse food products that have been developed utilizing T. molitor larvae as a key ingredient. Highlighting the nutritional, sensory, and sustainability aspects of these products, this review offers valuable insights to harness the potential of this alternative protein source to meet the evolving needs of modern food systems.

Establishment of porcine fecal-derived ex vivo microbial communities to evaluate the impact of livestock feed on gut microbiome

Sustainable livestock production requires reducing competition for food and feed resources and increasing the utilization of food by-products in livestock feed. This study describes the establishment of an anaerobic batch culture model to simulate pig microbiota and evaluate the effects of a food by-product, wakame seaweed stalks, on ex vivo microbial communities. We selected one of the nine media to support the growth of a bacterial community most similar in composition and diversity to that observed in pig donor feces. Supplementation with wakame altered the microbial profile and short-chain fatty acid composition in the ex vivo model, and a similar trajectory was observed in the in vivo pig experimental validation. Notably, the presence of wakame increased the abundance of Lactobacillus species, which may have been due to cross-feeding with Bacteroides. These results suggest the potential of wakame as a livestock feed capable of modulating the pig microbiome. Collectively, this study highlights the ability to estimate the microbiome changes that occur when pigs are fed a specific feed using an ex vivo culture model.

Effects of increasing levels of orange peel extract on kit growth, feed utilization, and some blood metabolites in the doe rabbits under heat stress conditions

One of the most severe consequences of climate change on the rabbit production sector is heat stress. Dietary supplementation of phytochemicals could alleviate the negative impact of heat stress on rabbits. Thirty-six V-line rabbit does with average live body weight (LBW) of 2.672 ± 0.031 kg were randomly allocated into three experimental groups as follows: the control group (OPE0) and the OPE2.5 and OPE5 groups were orally administered orange peel extract (OPE) at doses of 2.5 and 5 mL/doe. The increasing OPE levels significantly improved LBW at partum (p = 0.002) and weaning (p = 0.004), daily and total feed intake from pregnancy until weaning (p = 0.007), daily milk yield per doe at 7th and 14th days (p ≤ 0.05), and milk efficiency (p = 0.001). Litter size at 1st-28th days, litter weight gain, survival rate, and kit weight gain at 21st-28th days of heat-stressed doe rabbits were significantly improved with OPE treatments. The treatment of OPE5 significantly decreased serum glucose, triglycerides, and very-low-density lipoprotein-cholesterol levels of rabbits. The increasing OPE levels decreased significantly total lipid and low-density lipoprotein-cholesterol levels and increased (p = 0.001) high-density lipoprotein-cholesterol concentration in heat-stressed rabbits. In conclusion, the treatment of OPE improved feed utilization, milk efficiency, and reproductive performance and alleviated the drastic impacts of heat stress on rabbits.

Quantitative assessment, spatial and temporal characteristics, and dynamic evolution of carbon emissions from animal husbandry in China: 2001-2020

Carbon emissions from animal agriculture are a major source of global greenhouse gases. This paper measures the spatial and temporal characteristics and evolution patterns of carbon emissions from livestock farming in China and 31 provinces from 2001 to 2020 based on IPCC coefficients. The paper also uses Moran's I index, kernel density estimation, and spatial Markov chains for the analysis. The results show that the total carbon emissions from China's livestock sector show a fluctuating downward trend. And livestock carbon emissions are concentrated in areas with better resource endowments, with grassland and grain-producing areas dominating China's livestock carbon emissions. The spatial analysis shows that the spatial correlation of the national livestock carbon emissions is increasing, showing prominent local aggregation characteristics, mainly in the form of high-high and low-low aggregation. The transfer of carbon emissions from China's livestock industry shows strong spatial and temporal dependence, and the transfer of regional carbon emissions is limited by the original type and stock of carbon emissions, showing growth inertia and path dependence. The findings of this paper can provide suggestions for planning and modifying policies to reduce carbon emissions in China's livestock industry.

Proposed solutions to anthropogenic climate change: A systematic literature review and a new way forward

Humanity is now facing what may be the biggest challenge to its existence: irreversible climate change brought about by human activity. Our planet is in a state of emergency, and we only have a short window of time (7-8 years) to enact meaningful change. The goal of this systematic literature review is to summarize the peer-reviewed literature on proposed solutions to climate change in the last 20 years (2002-2022), and to propose a framework for a unified approach to solving this climate change crisis. Solutions reviewed include a transition toward use of renewable energy resources, reduced energy consumption, rethinking the global transport sector, and nature-based solutions. This review highlights one of the most important but overlooked pieces in the puzzle of solving the climate change problem - the gradual shift to a plant-based diet and global phaseout of factory (industrialized animal) farming, the most damaging and prolific form of animal agriculture. The gradual global phaseout of industrialized animal farming can be achieved by increasingly replacing animal meat and other animal products with plant-based products, ending government subsidies for animal-based meat, dairy, and eggs, and initiating taxes on such products. Failure to act will ultimately result in a scenario of irreversible climate change with widespread famine and disease, global devastation, climate refugees, and warfare. We therefore suggest an "All Life" approach, invoking the interconnectedness of all life forms on our planet. The logistics for achieving this include a global standardization of Environmental, Social, and Governance (ESG) or similar measures and the introduction of a regulatory body for verification of such measures. These approaches will help deliver environmental and sustainability benefits for our planet far beyond an immediate reduction in global warming.

The ecological footprint of physicians: A survey of physicians in Canada, India, and USA

Combating climate change may be the greatest public health opportunity of the 21st century. While physicians play an important role in addressing climate change, given their affluence in society, they may be an important source of greenhouse gas emissions themselves. We sought to examine the size and nature of the ecological footprint of physicians and medical students. We conducted an online survey from December 2021-May 2022 examining resource consumption, changes in consumption patterns over time, and beliefs about climate change. Participants were medical students, residents, and staff physicians in Canada, India, or USA. Only 20 out of 162 valid respondents had a low ecological footprint (12%), defined as meat intake ≤2 times per week, living in an apartment or condominium, and using public transport, bicycle, motorcycle or walking to work. 14 of these 20 participants were from India. 91% of participants were open to reducing their own ecological footprint, though only 40% had made changes in that regard. 49% participants who discussed climate change at work and at home had decreased their ecological footprint, compared to 29% of participants who rarely engaged in such conversations (OR 2.39, 95% CI 1.24-4.63, P = 0.01). We conclude that physicians have a large ecological footprint, especially those from Canada and USA. A majority of physicians are interested in reducing their ecological footprint, and those who engage in conversations around climate change are more likely to have done so. Talking frequently about climate change, at work and at home, will likely increase climate change action amongst physicians.

Effect of Chitosan on Ruminal Fermentation and Microbial Communities, Methane Emissions, and Productive Performance of Dairy Cattle

This study aimed to expand the knowledge about the activity and mode of action of CHI on methanogenesis and rumen microbial populations in vivo. A total of 16 lactating dairy cows were distributed in two groups, one of them receiving 135 mg CHI/kg body weight daily. The effect on productive performance, milk composition, fermentation efficiency, methane emissions, microbial protein synthesis, and ruminal microbial communities was determined. Supplementation with CHI did not affect rumen microbial diversity but increased the relative abundance (RA) of the bacteria Anaeroplasma and decreased those of rumen ciliates and protozoa resulting in a shift towards a lower acetic to propionic ratio. However, no effect on milk yield or methane intensity was observed. In conclusion, supplementing 135 mg CHI/kg body weight increased the RA of Anaeroplasma and decreased those of rumen ciliates and protozoa, both being related to fiber degradation in the rumen in different ways and resulted in a shift of ruminal fermentation towards more propionate proportions, without affecting CH4 emissions, milk yield, or milk composition. Further research with higher doses would be necessary to assess the potential use of this additive as a methane inhibitor.

Marine Microalgae as a Nutritive Tool to Mitigate Ruminal Greenhouse Gas Production: In Vitro Fermentation Characteristics of Fresh and Ensiled Maize (Zea mays L.) Forage

The aim of the present study was to evaluate the effects of marine microalgae (Dunaliella salina) as a food additive on biogas (BG), methane (CH4), carbon monoxide (CO), and hydrogen sulfide (H2S) production kinetics, as well as in in vitro rumen fermentation and the CH4 conversion efficiency of different genotypes of maize (Zea mays L.) and states of forage. The treatments were characterized by the forage of five maize genotypes (Amarillo, Montesa, Olotillo, Tampiqueño, and Tuxpeño), two states of forage (fresh and ensiled), and the addition of 3% (on DM basis) of microalgae (with and without). The parameters (b = asymptotic production, c = production rate, and Lag = delay phase before gas production) of the production of BG, CH4, CO, and H2S showed an effect (p < 0.05) of the genotype, the state of the forage, the addition of the microalgae, or some of its interactions, except for the time in the CO delay phase (p > 0.05). Moreover, the addition of microalgae decreased (p < 0.05) the production of BG, CH4, and H2S in most of the genotypes and stages of the forage, but the production of CO increased (p < 0.05). In the case of fermentation characteristics, the microalgae increased (p < 0.05) the pH, DMD, SCFA, and ME in most genotypes and forage states. With the addition of the microalgae, the fresh forage from Olotillo obtained the highest pH (p < 0.05), and the ensiled from Amarillo, the highest (p < 0.05) DMD, SCFA, and ME. However, the ensiled forage produced more (p < 0.05) CH4 per unit of SFCA, ME, and OM, and the microalgae increased it (p < 0.05) even more, and the fresh forage from Amarillo presented the highest (p < 0.05) quantity of CH4 per unit of product. In conclusion, the D. salina microalga showed a potential to reduce the production of BG, CH4, and H2S in maize forage, but its effect depended on the chemical composition of the genotype and the state of the forage. Despite the above, the energy value of the forage (fresh and ensiled) improved, the DMD increased, and in some cases, SCFA and ME also increased, all without compromising CH4 conversion efficiency.

Dietary Ruminant Enteric Methane Mitigation Strategies: Current Findings, Potential Risks and Applicability

This review examines the current state of knowledge regarding the effectiveness of different dietary ruminant enteric methane mitigation strategies and their modes of action together with the issues discussed regarding the potential harms/risks and applicability of such strategies. By investigating these strategies, we can enhance our understanding of the mechanisms by which they influence methane production and identify promising approaches for sustainable mitigation of methane emissions. Out of all nutritional strategies, the use of 3-nitrooxypropanol, red seaweed, tannins, saponins, essential oils, nitrates, and sulfates demonstrates the potential to reduce emissions and receives a lot of attention from the scientific community. The use of certain additives as pure compounds is challenging under certain conditions, such as pasture-based systems, so the potential use of forages with sufficient amounts of plant secondary metabolites is also explored. Additionally, improved forage quality (maturity and nutrient composition) might help to further reduce emissions. Red seaweed, although proven to be very effective in reducing emissions, raises some questions regarding the volatility of the main active compound, bromoform, and challenges regarding the cultivation of the seaweed. Other relatively new methods of mitigation, such as the use of cyanogenic glycosides, are also discussed in this article. Together with nitrates, cyanogenic glycosides pose serious risks to animal health, but research has proven their efficacy and safety when control measures are taken. Furthermore, the risks of nitrate use can be minimized by using probiotics. Some of the discussed strategies, namely monensin or halogenated hydrocarbons (as pure compounds), demonstrate efficacy but are unlikely to be implemented widely because of legal restrictions.

Dual-Purpose Cattle Raised in Tropical Conditions: What Are Their Shortcomings in Sound Productive and Reproductive Function?

Dual-purpose husbandry might well be the most commonly employed cattle management system in tropical regions worldwide. The advantages of producing both meat and milk, although in reduced quantities, gives an edge to the farmer in coping with the volatile economic conditions that prevail in the region. Herein, we discuss the different methods of cattle management under tropical conditions based on the financial and social structure of this system. An account of the sanitary and nutritional conditions available to the farmers and how these factors affect the profitability of the enterprise will also be given. Finally, we will discuss how these systems can take advantage of several biotechnological procedures, and how these tools (such as controlled natural mating, artificial insemination, and embryo transfer) affect reproductive outcomes. The present review will mainly concentrate on production systems located less than 1000 m above sea level, as the problems and shortcomings of cattle raised above this arbitrary landmark are quite different.

Effect of Pelagic Sargassum on In Vitro Dry Matter and Organic Matter Degradation, Gas Production, and Protozoa Population

This study determined the effect of pelagic Sargassum on in vitro dry matter and organic matter degradation, total gas production (TGP), and protozoa population. The treatments were different levels of Sargassum inclusion on a basal substrate (Stargrass hay; Cynodon nlemfuensis) as follows: T0 (control treatment based on Stargrass hay), T10 (90% Stargrass hay + 10% Sargassum), T20 (80% Stargrass hay + 20% Sargassum), and T30 (70% Stargrass hay + 30% Sargassum). Ruminal fermentation kinetics and protozoa population were determined during 72 h of in vitro incubations. Compared to control, dry matter degradability at 48 and 72 h and organic matter degradability at 24 and 48 h were higher in Sargassum treatments. TGP was lower with T20 at 48 h. The total population of protozoa and the concentration of Entodinium spp. were lower at T20 at 48 h and T30 at 72 h. Cl, S, Ca, K, and Zn (103, 5.97, 88.73, 285.70 g/kg, and 15,900 mg/kg) were high in Sargassum, reaching twice or even nine times higher than the contents in Stargrass (11.37, 1.60, 43.53, 87.73 g/kg, and 866.67 mg/kg). Overall, up to 30% pelagic Sargassum could be included in hay-based substrates from tropical grasses without negative effects on in vitro dry matter and organic matter degradability.

Potential of Seaweeds to Mitigate Production of Greenhouse Gases during Production of Ruminant Proteins

The potential of seaweed to mitigate methane is real and studies with red seaweeds have found reductions in methane produced from ruminants fed red seaweeds in the region of 60-90% where the active compound responsible for this is bromoform. Other studies with brown and green seaweeds have observed reductions in methane production of between 20 and 45% in vitro and 10% in vivo. Benefits of feeding seaweeds to ruminants are seaweed specific and animal species-dependent. In some instances, positive effects on milk production and performance are observed where selected seaweeds are fed to ruminants while other studies note reductions in performance traits. A balance between reducing methane and maintaining animal health and food quality is necessary. Seaweeds are a source of essential amino acids and minerals however, and offer huge potential for use as feeds for animal health maintenance once formulations and doses are correctly prepared and administered. A negative aspect of seaweed use for animal feed currently is the cost associated with wild harvest and indeed aquaculture production and improvements must be made here if seaweed ingredients are to be used as a solution to control methane production from ruminants for continued production of animal/ruminant sourced proteins in the future. This review collates information concerning different seaweeds and how they and their constituents can reduce methane from ruminants and ensure sustainable production of ruminant proteins in an environmentally beneficial manner.

Enteric methane emission estimates for the Zimbabwean Sanga cattle breeds of Tuli and Mashona

The effectiveness of methane mitigation in ruminant livestock production systems depends on the accuracy of estimating methane emission factors and providing accurate emission inventories. Following the Paris Climate agreement, it is recommended that countries adopt the Tier-2 approach for estimating enteric methane emissions from ruminants instead of the Tier-1 approach currently used by most countries. This study sought to provide base line enteric methane emission estimates for the Tuli and Mashona Sanga cattle breeds in Zimbabwe using the IPCC Tier-2 model. Using animal characterization data collected from 412 cattle from Grasslands Research Institute and 406 cattle from Makoholi Research Institute, net energy requirements were estimated. From this and the estimate for digestibility, gross energy intake and dry matter intake were estimated. Gross energy intakes and the estimated methane conversion factor were used to estimate enteric methane emissions. Mean emission factors for Tuli were 45.1, 56, 28.5, 28.4 and 20.6 kg CH₄/head/year for cows, bulls, heifers, steers and calves, respectively. For Mashona, they were 47.8, 51.9, 29, 29.1 and 20.7 kgCH₄/head/year for cows, bulls, heifers, steers and calves, respectively. Generally, estimated Tier-2 emission factors were significantly different from the IPCC Tier-1 default emission factors. This study concluded that enteric methane emission factors estimated using the IPCC Tier-2 model offer insights into the controversial use of the default IPCC Tier-1 emission factors.

Sustainability of dairy systems through the lenses of the sustainable development goals

In this paper, we propose to view the sustainability of dairy farming as nested within the sustainability of agriculture, a subset of the sustainability of food systems, which in turn could be construed as a subset of the national commitments of a country to achieve the Sustainable Development Goals (SDGs). Disciplinary, multidisciplinary, and interdisciplinary research are essential to study bio-physical system components and their interactions. However, when dairy farming is viewed as nested within broader societal systems, the inclusion of human elements calls for transdisciplinary research. Few of the 17 SDGs are left untouched by the livestock sector. Research should aim at identifying relevant farm-level metrics that are in alignment with any of the 231 indicators supporting the SDGs. We used two examples to illustrate the approach. In the first, SDG 13 (Climate Action) is used as a reminder that despite the current emphasis on reducing milk carbon footprint (kg CO2-e/kg milk), the contribution of the sector to Climate Action depends on reducing its annual emission (kg CO2-e/year; indicator 13.2.2). In the second example, indicator 2.4.1 (land use for sustainable agriculture) of SDG 2 (Zero Hunger) is used to illustrate the potential tradeoffs between Milk N/Intake N as a metric of nitrogen use efficiency at the cow level and metrics such as the input:output ratio of human-edible protein (Milk N/Intake of human-edible N) that prioritize the use of human-inedible feed in dairy rations as a way to enhance efficiency and circularity at the food system level.

Biofortification of common bean (Phaseolus vulgaris L.) with iron and zinc: Achievements and challenges

Micronutrient deficiencies (hidden hunger), particularly in iron (Fe) and zinc (Zn), remain one of the most serious public health challenges, affecting more than three billion people globally. A number of strategies are used to ameliorate the problem of micronutrient deficiencies and to improve the nutritional profile of food products. These include (i) dietary diversification, (ii) industrial food fortification and supplements, (iii) agronomic approaches including soil mineral fertilisation, bioinoculants and crop rotations, and (iv) biofortification through the implementation of biotechnology including gene editing and plant breeding. These efforts must consider the dietary patterns and culinary preferences of the consumer and stakeholder acceptance of new biofortified varieties. Deficiencies in Zn and Fe are often linked to the poor nutritional status of agricultural soils, resulting in low amounts and/or poor availability of these nutrients in staple food crops such as common bean. This review describes the genes and processes associated with Fe and Zn accumulation in common bean, a significant food source in Africa that plays an important role in nutritional security. We discuss the conventional plant breeding, transgenic and gene editing approaches that are being deployed to improve Fe and Zn accumulation in beans. We also consider the requirements of successful bean biofortification programmes, highlighting gaps in current knowledge, possible solutions and future perspectives.

In Vitro Studies on Rumen Fermentation and Methanogenesis of Different Microalgae and Their Effects on Acidosis in Dairy Cows

Two in vitro studies were carried out on nonlactating dairy cows. Experiment 1 compared the methanogenesis and rumen fermentation parameters of various microalgae (Spirulina platensis, Chlorella vulgaris, and Schizochytrium spp.) and protein feeds (sunflower meal, soybean meal, and alfalfa hay) with monensin (MON). Rumen fermentation parameters were determined by an in vitro gas production system. Experiment 2 compared the ability of three microalgae to prevent acidosis. They were tested for 6 h against oat straw (100 mg) and MON (12 g/mL) to ameliorate ruminal acidosis caused by the addition of glucose (0.1 g/mL) as a fermentable carbohydrate with rumen fluid. In experiment 1, there were variations in the nutrient content of microalgae and protein sources. The dry matter content of the substrates ranged from 90 to 94%, and the organic matter content ranged from 82 to 88%, with Schizochytrium spp. having the highest. Protein content in algae and protein feeds ranged from 18–62% of dry matter (DM) to 16–48% DM, with S. platensis and C. vulgaris having the highest. The ether extract of Schizochytrium spp. (45.5% DM) was the highest of any substrate. In vitro rumen fermentation revealed that protein feeds increased the cumulative gas production at the highest level while MON caused a decrease. Ruminal pH was found to be higher in MON (6.95) and protein feeds (6.77–6.81) than in algae (6.37–6.50). In addition, in terms of metabolizable energy and digestible organic matter, protein feeds outperformed algae. The MON produced the least amount of methane (CH4) of any substrate, but Schizochytrium spp. demonstrated potential for CH4 reduction. In these groups, the decrease in CH4 production was accompanied by a decrease in total volatile fatty acids, acetate, and the acetate-to-propionate ratio, but an increase in propionate. Experiment 2 revealed MON as the most effective cure for controlling acidosis. However, C. vulgaris and Schizochytrium spp. had an effect on medium culture pH and demonstrated potential for acidosis prevention. This study found that algae can influence ruminal fermentation, have the potential to reduce CH4 production, and may reduce acidosis incidence rates. These assumptions, however, must be validated through in vivo studies.

Assessment of a 50:50 mixture of two Bacillus subtilis strains as growth promoters for finishing pigs: productivity improvement and noxious gas reduction

In this study, we aimed to assess the potential of a 50:50 mixture of two Bacillus subtilis strains in improving the productivity and health of finishing pigs and reducing noxious gases in their feces. These strains were found to abundantly secrete surfactin which has been shown to alleviate the effects of lipopolysaccharides in vitro. For the 10-wk experiment, 200 finishing pigs ([Landrace × Yorkshire] × Duroc) with an average body weight of 54.15 ± 1.70 kg were divided into four groups. Each group was fed with a basal diet supplemented with an equal amount of spores from the two B. subtilis strains at different levels: control group, no addition; treatment group 1, 0.5 × 109; treatment group 2, 1.0 × 109; treatment group 3, 1.5 × 109 cfu·kg-1 addition. During the 10-wk feeding period, dietary supplementation of 0.5 × 109, 1.0 × 109, and 1.5 × 109 cfu·kg-1 of the spore cells from these two strains resulted in a 0.9%, 1.9%, and 2.5% increase in body weight, respectively (linear P < 0.095). During the final 5 wk, the average daily gain (ADG) in weight was increased by the strains at amounts of 0.5 × 109, 1.0 × 109, and 1.5 × 109 cfu·kg-1 with a clear dosage effect (linear P < 0.05). However, neither the gain-to-feed ratio, the average daily feed intake, nor nutrient digestibility was affected by the supplementation. In blood, the endotoxin lipopolysaccharides, and two liver toxicity indicator enzymes; aspartate aminotransferase and lactate dehydrogenase were decreased (P < 0.05) in the 1.0 × 109 cfu·kg-1 spores-feeding group. Furthermore, four noxious gases were reduced by 8 to 20% in feces excreted by pigs fed with 1.5 × 109 cfu·kg-1 spores with a linear dosage effect (linear P < 0.001 to 0.05) during the final 5 wk. Our findings suggest that the mixture of B. subtilis strains may enhance the productivity of finishing pigs by reducing the risk of mild endotoxemia, rather than increasing digestibility or daily feed intake. Therefore, these Bacillus strains have the potential to act as growth promoters for pigs, leading to improved animal health and productivity. These results have significant implications for pig farmers seeking to optimize the health and growth of their animals.

Associative effects between Chlorella vulgaris microalgae and Moringa oleifera leaf silage used at different levels decreased in vitro ruminal greenhouse gas production and altered ruminal fermentation

Moringa oleifera leaf silage and Chlorella vulgaris microalgae mixture used at different levels replacing concentrate feed mixture in the diets of ruminant were evaluated using an in vitro gas production technique. C. vulgaris was included in rations at 1, 2, and 3% concentrations. The concentrate feed mixture was replaced by M. oleifera silage up to 100%. Productions of total gas, methane (CH₄), and carbon dioxide (CO₂) and ruminal fermentation were measured. Interactions between M. oleifera and C. vulgaris levels were observed for the rate of total gas production, lag time of CH₄ production, pH, and concentrations of ammonia-N (NH₃-N), total volatile fatty acid (VFA), and propionate. The lower level of C. vulgaris increased total gas production and decreased CH₄ and CO₂ production as well as improved nutrient degradability compared to the other levels of C. vulgaris which showed less improvement in these parameters. The replacement levels of concentrate at 10 to 40% with M. oleifera linearly increased the asymptotic total gas production and degradabilities of dry matter and acid detergent fiber (P<0.05), while the replacement levels of 80 to 100% lowered the asymptotic (P<0.01) for the ration containing 1% C. vulgaris. Rations containing M. oleifera linearly increased the lag time of total gas production (P<0.05), neutral detergent fiber degradability, and ruminal bacteria count and decreased the asymptotic CH₄ and CO₂ production and ruminal protozoal count (P<0.05). For the rations containing 2 and 3% C. vulgaris, M. oleifera linearly (P<0.01) decreased the asymptotic total gas, CH₄ and CO₂ production, and ruminal protozoal count. The lag time of CH₄ production was not affected at 1% C. vulgaris, but reduced linearly at 2% and 3% C. vulgaris. Ruminal pH was not affected by M. oleifera, but was increased by C. vulgaris at 3% level. Overall, M. oleifera in the ration containing C. vulgaris at all levels increased ruminal NH₃-N concentration; however, C. vulgaris at 2% level and M. oleifera at levels up to 40% lowered NH₃-N concentration. M. oleifera rations with 1% and 2% C. vulgaris increased the concentrations of total VFA and propionate, whereas these variables were not affected at 3% C. vulgaris level. In conclusion, replacement of concentrate mixture with M. oleifera at 30% level and C. vulgaris at 1% in the diet due to associative effects may improve ruminal fermentation and feed degradability while decreasing CH₄ production.

Predicting Site Energy Usage Intensity Using Machine Learning Models

Climate change is a shift in nature yet a devastating phenomenon, mainly caused by human activities, sometimes with the intent to generate usable energy required in humankind's daily life. Addressing this alarming issue requires an urge for energy consumption evaluation. Predicting energy consumption is essential for determining what factors affect a site's energy usage and in turn, making actionable suggestions to reduce wasteful energy consumption. Recently, a rising number of researchers have applied machine learning in various fields, such as wind turbine performance prediction, energy consumption prediction, thermal behavior analysis, and more. In this research study, using data publicly made available by the Women in Data Science (WiDS) Datathon 2022 (contains data on building characteristics and information collected by sensors), after appropriate data preparation, we experimented four main machine learning methods (random forest (RF), gradient boost decision tree (GBDT), support vector regressor (SVR), and decision tree for regression (DT)). The most performant model was selected using evaluation metrics: root mean square error (RMSE) and mean absolute error (MAE). The reported results proved the robustness of the proposed concept in capturing the insight and hidden patterns in the dataset, and effectively predicting the energy usage of buildings.

Rethinking efficiency: Growth curves as a proxy for inputs and impacts in finishing beef systems

Quantifying and improving efficiency within beef systems is essential for economic and environmental sustainability. The industry standard for assessing efficiency is liveweight gain per day, however, this metric is limited in that it values each day of a growing animal's life as equally costly, despite the increasing maintenance requirements, inputs, and emissions associated with increasing liveweight. Quantifying the area under the growth curve (AUC) considers both time and liveweight as a cost and therefore may hold potential as a better estimate of cost, impact, and efficiency in beef systems. Liveweight data was taken from 439 finishing beef cattle split across three herds grazing on different pastures, known as 'farmlets'. Analysis was conducted in three parts: [1] Validation of AUC as a proxy for costs using data from a sub-set of 87 animals that had been part of a previous life cycle assessment (LCA) study in which dry matter intake (DMI), methane emissions (CH₄), and nitrous oxide emissions (N₂O) were calculated. [2] Calculation of AUC relative to liveweight gain (LWG AUC^-1) and comparison of that metric against the industry standard of liveweight gain per day (LWG day^-1). [3] Assessment of how LWG AUC^-1 varied with breed, sex, and management. When comparing to LCA results, AUC correlated significantly with DMI (r = 0.886), CH₄ (r = 0.788) and N₂O (r = 0.575) emissions. Over the full dataset, there was a negative non-linear relationship between LWG AUC^-1 and slaughter age (r = -0.809). There was a significant difference in LWG AUC^-1 between breeds (p = 0.046) and farmlets (p = 0.028), but not sex (p = 0.388). LWG AUC^-1 has the potential to act as a proxy for feed intake and emissions. In that regard it is superior to LWG day^-1, whilst requiring no additional data. Results highlighted the decreasing efficiency of beef cattle over time and the potential benefits of earlier slaughter. The use of LWG AUC^-1 could allow farmers to improve their understanding of efficiency within their herds, aiding informed management decision making.

Enhancement of fruit byproducts through bioconversion by Hermetia illucens (Diptera: Stratiomyidae)

Bioconversion is a biological process by which organic materials are converted into products with higher biological and commercial value. During its larval stage the black soldier fly Hermetia illucens is extremely voracious and can feed on a wide variety of organic materials. To study the impact of different fruit byproducts on the insect's growth, final larval biomass, substrate reduction, bioconversion parameters, and larval nutritional composition, 10 000 black soldier fly larvae (BSFL) were reared on 7.0 kg of one of three substrates (strawberry, tangerine, or orange) or on a standard diet as a control. The results highlight that BSFL can successfully feed and grow on each of these diets, though their development time, growth rate, and final biomass were differently impacted by the substrates, with strawberry being the most suitable. The lipid and protein contents of BSFL were similar among larvae fed on different substrates; however, major differences were detected in ash, micronutrient, fiber, fatty acid, and amino acid contents. Overall, the results indicate that fruit waste management through the BSFL bioconversion process represents a commercially promising resource for regional and national agrifood companies. Our study offers new perspectives for sustainable and environmentally friendly industrial development by which fruit byproducts or waste might be disposed of or unconventionally enhanced to create secondary products of high biological and economic value, including BSFL biomass as animal feed or, in perspective, as alternative protein source for human nutrition.

Innovation in Alternative Food Sources: A Review of a Technological State-of-the-Art of Insects in Food Products

Insects present great potential for the food industry due to their easier rearing conditions and high nutritional value, in comparison with traditional livestock. However, there is a lack of evaluation of the technological status of food products developed with edible insects. Therefore, this study aims to analyze the emergent technological and scientific applications of edible insects in the food industry through a prospective study of patent documents and research articles. Espacenet was used as a research tool, applying the terms Insect, Pupa, Larva, or Nymph and the codes A23L33 and A23V2002. A total of 1139 documents were found-341 were related to the study. Orbit^® was used to evaluate technological domains and clusters of concepts. Scopus database research was performed to assess the prevalence of insect research, with the term "edible and insect*". The main insects used were silkworms, bees, beetles, mealworms, crickets, and cicadas. Protein isolates were the predominant technology, as they function as an ingredient in food products or supplements. A diverse application possibility for insects was found due to their nutritional composition. The insect market is expected to increase significantly in the next years, representing an opportunity to develop novel high-quality/sustainable products.

A preliminary evaluation on mixed probiotics as an antimicrobial spraying agent in growing pig barn

The purpose of this study is to examine whether spraying an anti-microbial agent into the slurry pit will reduce the noxious odor substances from piggery barns. For this, a total of 200 crossbred ([Landrace × Yorkshire] × Duroc) growing pigs with an initial average body weight (BW) of 23.58 ± 1.47 kg were selected and housed in two different rooms, i.e. control (CON) and treatment (TRT). Each room has 100 pigs (60 gilts and 40 borrows). For a period of 42 days, all pigs were fed with corn-soybean meal-based basal diet. Later the noxious odor substances were measured by the following methods. First, fecal samples were randomly collected and stored in sealed and unsealed containers, and sprayed with the non-anti-microbial agent (NAMA) (saline water) and multi-bacterial spraying (MBS) agent (200 :1, mixing ratio-fecal sample : probiotic), Second, the slurry pit of CON and TRT rooms were directly sprayed with NAMA and MBS, respectively. The fecal sample that was stored in sealed and un-sealed containers and sprayed with MBS significantly reduced NH3 and CO₂ concentration at the end of day 7. However, at the end of day 42, the fecal sample showed a lower H₂S, methyl mercaptans, acetic acid, and CO₂ concentration compared to the unsealed container. Moreover, at the end of days 7, 14, 21, 28, 35, and 42 compared to the CON room and TRT room slurry pit emits lower concentrations of NH₃, acetic acid, H₂S, and methyl mercaptans, and CO₂ into the atmosphere. Based on the current findings, we infer that spraying anti-microbial agents on pig dung would be one of the better approaches to suppress the odor emission from the barn in the future.

Climate change adaptation options to inform planning of agriculture and food systems in The Gambia: A systematic approach for stocktaking

Identifying and assessing adaptation options are key pre-requisite steps to adaptation prioritization and effective adaptation planning. In this paper, we presented a systematic approach for adaptation stocktaking, combining a systematic mapping and an outcome-oriented and evidence-based assessment, illustrated using the case of The Gambia. This study systematically mapped 24 adaptation options that can potentially inform adaptation planning in The Gambia agriculture and food systems and assessed how the identified options contribute to the pillars of Climate-Smart Agriculture. Because of the paucity of evidence sources from The Gambia, we collated evidence from both The Gambia and the West Africa region. We found that many of the documented options, such as climate-resilient crop varieties, crop diversification, climate information use, and weather indexed-based insurance have the potential to increase agricultural productivity and income while building resilience to climate change. While several options, such as soil and water conservation practices can positively contribute to climate change mitigation, others such as manure and inorganic fertilizers can have no or negative impacts on mitigation. Agroforestry practices and System of Rice Intensification have the potential to make a triple impact. The paucity of evidence from The Gambia and the highly contextual and differential impacts of the identified adaptation options underscore the importance of careful consideration of barriers and enablers when developing and deploying policy and interventions to sustainably increase productivity and income while building resilience to climate risks and reducing GHGs emissions. Stakeholder engagement and participatory research action are crucial in selecting and testing the priority adaptation options which can maximize their potentials in specific agricultural and food system contexts, such as in The Gambia. Because of the heterogeneity in household vulnerability and socioecological circumstances, targeting options to the right contexts will also be crucial to avoid maladaptation. We highlighted key knowledge gaps in the understanding of the effectiveness and feasibility of the identified adaptation options in The Gambia. Beyond The Gambia, the approach can also be useful for and replicated in other least developed countries in the West African region, that are currently developing their National Adaptation Plan.