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The objective was to evaluate the effect of 3-nitrooxypropanol (3-NOP) in combination with different feed additives on growth performance, carcass traits, meat quality, enteric methane (CH4) emissions, nutrient intake and digestibility, and blood parameters in feedlot beef cattle. In experiment (Exp.) 1, one hundred sixty-eight Nellore bulls (initial bodyweight (BW) 410 ± 8 kg) were allocated to 24 pens in a completely randomized block design. In Exp. 2, thirty Nellore bulls (Initial BW 410 ± 3 kg) were allocated to a collective pen in a completely randomized design. Three treatments were applied: Control (CTL): Sodium monensin (26 mg/kg of dry matter, DM), M3NOP: CTL with 3-NOP (100 mg/kg DM) and Combo: 3-NOP (100 mg/kg DM) with essential oils (100 mg/kg DM), 25-Hydroxy-Vitamin-D3 (0.10 mg/kg DM), organic chromium (4 mg/kg DM), and zinc (60 mg/kg DM). In Exp 1, bulls in Combo had greater (P<0.01) dry matter intake (DMI) at d 28 compared with CTL and M3NOP. During d 0 to 102, bulls final BW and average daily gain (ADG) were greater (P≤0.03) for Combo compared with CTL. Bulls in Combo and M3NOP had better (P<0.01) feed conversion (FC) and feed efficiency (FE) compared with CTL. Hot carcass weight (HCW), carcass ADG and carcass yield were greater (P≤0.05) for bulls from Combo compared with CTL and M3NOP. Bulls in Combo had greater (P=0.01) dressing compared with M3NOP. Combo bulls had better (P=0.02) biological efficiency compared with CTL. Bulls in Combo had lower (P<0.01) carcass pH compared to CTL and M3NOP. In Exp. 2, bulls in Combo had greater (P=0.04) DMI at d 28 compared with CTL and had greater (P<0.01) DMI at d 102 compared with CTL and M3NOP. Bulls in Combo had greater (P=0.04) HCW compared with CTL and M3NOP and carcass ADG was greater (P=0.04) for bulls Combo compared with M3NOP. Bulls in Combo and M3NOP had lower (P<0.01) CH4 production (38.8%, g/d), yield (41.1%, g/kg DMI), intensity (40.8%, g/kg carcass ADG) and increased (P<0.01) H2 emissions (291%, g/d) compared with CTL. Combo bulls had lower (P<0.01) blood glucose and insulin, and higher nutrient intake and digestibility (P≤0.05) compared with CTL and M3NOP. Combining 3-NOP with different feed additives improved FC, FE, and reduced enteric CH4 emissions. Combo treatment improved growth performance, carcass traits, nutrient intake and digestibility, and improved glucose and insulin responses in feedlot beef cattle on a high-concentrate finishing diet.

Abstract Biochar has the potential to increase crop yields on degraded, tropical soils. It can be readily produced in rural community settings using low-cost technology and is most economically feasible if produced from local biomass or waste residues. Biochar was produced from Leucaena biomass using low-cost pyrolysis and sequential pot experiments were then conducted in Malaysia on three degraded soils. We first evaluated the effect of Leucaena biochar on yields of Amaranthus, a leafy vegetable crop and measured changes to soil pH and nutrient availability over two growth cycles. We then tested whether any yield response to biochar was dependent upon the rate of biochar or fertilizer application. We found that biochar application at 30 t ha−1 with maximal fertilizer increased yields between 17 and 53% on very strongly acidic soil. Biochar added at 15 t ha−1 with maximal fertilizer increased yield by 54% on strongly acidic soil whilst there was no significant yield response on fertilized, slightly acidic soil. Unfertilized biochar treatments showed small yield responses across all soils over 2 growth cycles (9–11%), but yields were much lower than in fertilized treatments. Biochar also decreased short-term N availability when applied with fertilizers, which may improve nitrogen retention and substantially increased soil pH. This may reduce mobility of Fe, Mn and Al ions, which were negatively associated with yield. Our results suggest that Leucaena biochar can elicit a positive crop yield response but only when combined with fertilizer additions on very strongly to strongly acidic tropical soils.

AbstractDesigning crop ideotypes in silico is a powerful tool to explore the crop yield potential and yield gap. We defined yield gap as the difference between yield potential of a crop ideotype optimized under local environment and yield of an existing cultivar under optimal management. Wheat ideotypes were designed for the current climate using the Sirius model for both water-limited and irrigated conditions in two high wheat-productive countries viz. the United Kingdom (UK) and New Zealand (NZ) with the objective of estimating yield gap. The mean ideotype yields of 15.0–19.0 t ha−1 were achieved in water-limited conditions in the UK and NZ, whereas 15.6–19.5 t ha−1 under irrigated conditions. Substantial yield gaps were found in both water-limited, 28–31% (4–6 t ha−1), and irrigated conditions, 30–32% (5–6 t ha−1) in the UK and NZ. Both yield potential (25–27%) and yield gap (32–38%) were greater in NZ than the UK. Ideotype design is generic and could apply globally for estimating yield gap. Despite wheat breeding efforts, the considerable yield gap still potentially exists in high productive countries such as the UK and NZ. To accelerate breeding, wheat ideotypes can provide the key traits for wheat improvement and closing the yield gap.

Under current trends, 60% of India's population (>10% of people on Earth) will experience severe food deficiencies by 2050. Increased production is urgently needed, but high costs and volatile prices are driving farmers into debt. Zero budget natural farming (ZBNF) is a grassroots movement that aims to improve farm viability by reducing costs. In Andhra Pradesh alone, 523,000 farmers have converted 13% of productive agricultural area to ZBNF. However, sustainability of ZBNF is questioned because external nutrient inputs are limited, which could cause a crash in food production. Here, we show that ZBNF is likely to reduce soil degradation and could provide yield benefits for low-input farmers. Nitrogen fixation, either by free-living nitrogen fixers in soil or symbiotic nitrogen fixers in legumes, is likely to provide the major portion of nitrogen available to crops. However, even with maximum potential nitrogen fixation and release, only 52-80% of the national average nitrogen applied as fertilizer is expected to be supplied. Therefore, in higher-input systems, yield penalties are likely. Since biological fixation from the atmosphere is possible only with nitrogen, ZBNF could limit the supply of other nutrients. Further research is needed in higher-input systems to ensure that mass conversion to ZBNF does not limit India's capacity to feed itself.

Organic farming, which is deeply rooted in traditional agricultural practices, has witnessed a profound evolution over the last century. Transitioning from a grassroots initiative resisting the industrialization of agriculture to a global industry, organic farming now plays a pivotal role in addressing contemporary challenges related to environmental health, sustainability, and food safety. Despite the growing consumer demand for organic products and market access, organic farming has its challenges. This paper discusses the origin and evolution of organic farming with an emphasis on different types of organic fertilizers, benefits, and challenges. Nutrient variability and the slow-release nature of organic fertilizer often do not meet crop demands and can substantially reduce yield. Some organic fertilizers, like manure and biosolids, can provide a higher yield benefit, but there are environmental and health risks associated with them. Weed and pest management in organic farming can be labor-intensive and increase costs. Inefficient planning of organic farming and rapid transition can also create food insecurity. This paper also gives a brief account of the current certification process for organic fertilizers and their technicalities. It showcases how the holistic approach of organic farming extends beyond production, including strategies like reducing food waste and building self-sufficient farming communities. These practices contribute to a more sustainable agricultural system, reducing environmental impacts and supporting local economies. Future technological innovations, especially in precision agriculture and bio-physicochemical models, can help in formulating targeted organic fertilizers.

A sustainable livestock economy depends on both production and consumption, inextricably linked in local, national and global markets. At each scale, technical innovation and production practices need to respond to evolving demand for both market and non-market attributes of livestock systems. This review considers recent and evolving demand-side challenges focussing on emerging preferences related to environmental, dietary and health impacts, arising from both production and consumption. It suggests that these attributes need to be integral to any definition of high-producing animal systems. This discussion is mostly framed using neoclassical economic theory, which highlights market failure and the role of negative and positive external effects or social costs. It examines how our understanding of the demand for these attributes is evolving, leading to market segmentation in some cases, and an existential threat to livestock production as consumption decisions change, investors seek to avoid potential liabilities related to greenhouse gas emissions and potentially antimicrobial resistance, and governments intervene to control other undesirable social costs. The discussion distinguishes between market imperatives in high- and lower-income countries, and how income and consumption trajectories may be less deterministic in a more hyperlinked world where product information may accelerate the evolution of preferences towards and away from livestock products. The review acknowledges the limits of a neoclassical approach, drawing attention to more fundamental concepts of biophysical limits to growth and value pluralism, which indicates values (e.g. intrinsic) that lie beyond the neoclassical framing of demand and value.

The recent discourse on food sovereignty places much emphasis on democracy in determining localized food systems, and whether the food is culturally appropriate while leaning heavily on sustainable agricultural practices such as organic agriculture, ecological intensification, agroecology, nature-based solutions, and regenerative agriculture. Sustainable agricultural practices are intended to ensure that the land is managed without the use of synthetic fertilizers and pesticides, while going further by focusing on improvements on soil and land health. However, what are the practicalities of food activism and relying entirely on nature while yields are still very low in much of sub-Saharan Africa (SSA)? We attempt to answer this question in four main sections: (a) we start by defining the concept of food sovereignty and the associated practices, (b) we highlight some of the main socio-ecological conditions that are common in SSA, and (c) we present evidence of some of the limitations of food sovereignty due to the diversity in ecological, political, cultural, and socio-economic contexts that characterize SSA; finally, (d) we focus on food preferences, marketing and certification aspects. We conclude that agroecology alone cannot solve the multiple objectives of increasing crop productivity and replenishing soil nutrients especially on small farms and relying on natural rainfall. There is an urgent need to combine superior crop varieties and judicious use of external inputs in tandem with the manipulation of the agroecological processes to increase the efficiency of input use and achieve higher food productivity, resilience to climate change, and preservation of the natural resource base in specific locations.