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Cryptosporidium prevalence in calves and its effect on local water quality prior to abstraction and treatment
Get PDFCryptosporidium spp., particularly Cryptosporidium parvum, pose a significant threat to raw water quality and public health. Cryptosporidiosis, a gastrointestinal zoonotic disease, causes diarrhoea in dairy and beef production systems worldwide. Infected calves shed Cryptosporidium spp. oocysts in faeces, posing risks of contaminating surface water sources. Understanding the dynamics of Cryptosporidium contamination is crucial for effective water quality management. This study investigated Cryptosporidium spp. prevalence in neonatal calves and its potential impact on water quality before abstraction and treatment. The study analysed faecal samples from 1–3-week-old calves on two English dairy farms upstream of a water abstraction point. Initial screening used C. parvum immune chromatographic assays (ICT) on 47 faecal samples. This was followed by DNA extraction and species identification, with gp60 subtyping. Raw and treated water quality data were analysed to determine Cryptosporidium oocyst counts. Cryptosporidium parvum was the predominant species in calves at both farms, with gp60 subtype IIaA17G2R1 being the only subtype detected. Some calf samples revealed mixed infections with C. parvum and C. ryanae. Raw-water samples (n = 214) revealed a 50.00% positivity rate for Cryptosporidium oocysts, with 22.43% (24/107) containing C. parvum/C. hominis and the remainder 77.57% (83/107) C. andersoni. Water treatment significantly reduced oocyst counts (P < 0.001); however, due to the increase in popularity of bathing in rivers, oocysts present in raw river water may still prove a public health risk
How to manage sustainability compliance in multi-tier crop agrifood supply chains through intermediaries?
Get PDFThis study investigates sustainability challenges in Pakistan’s rice multi-tier supply chain (MTSC), focusing on the socio-cultural and religious factors that sustain modern slavery and hinder sustainability efforts. A two-stage systematic literature review, incorporating mapping and evidence synthesis, established the theoretical foundation and guided the empirical investigation. The qualitative analysis reveals how cultural values, social hierarchies, and religious beliefs perpetuate exploitative labour practices in the MTSCs of Pakistan's rice industry. The study highlights how Agri Processing Company Limited (APCL), operating as a first-tier intermediary, effectively launched and managed different levels of intermediaries through ‘multi-actor’ and ‘multi-level’ management approaches to extend sustainability upstream in the rice supply chain, particularly in the lower tiers previously considered ‘commodities with no value’. Social networking and progressive farmers played inclusive roles as change agents in bringing all stakeholders of a traditional and fragmented supply chain into a coordinated platform. The bottom-up strategic management approach of APCL gained the trust of local stakeholders and buying firms, resulting in a sustainable business strategy. Increased collaboration at different levels of farming communities led to a transformed methodology for sustainable development through intermediaries. The transformed business structure and mediated governance of ‘multi actors' supply chains revamped socio-ecological outcomes for the lower-tiers and improved local living conditions through economic fairness and equal opportunities. This transformation has contributed significantly to advances in Pakistan's rice industry towards sustainable development. By demonstrating how intermediaries bridge institutional voids and mitigate socio-cultural resistance, this study broadens the understanding of sustainability in MTSCs. Future research should investigate the applicability of intermediary-driven management models across various industries and socioeconomic contexts. Investigating intermediary roles in global supply chains beyond agriculture could further reveal how socio-cultural and economic factors influence supply chain resilience and ethical labour practices
Price Transmission & Dynamic Connectedness: Consequences of US-China Trade War and the Ukrainian-Russian War in the International Agricultural Commodity Markets
Get PDFGlobal agricultural markets face unprecedented challenges from geopolitical tensions, raising concerns about food security and market efficiency. This dissertation examines how the international soybean market's resilience and
dynamics respond to major disruptions—specifically the US-China trade war and the Russian-Ukrainian conflict. The research investigates changes in market efficiency, price transmission, and global market integration within the soybean industry during these periods of stress.
The study employs multiple econometric approaches to capture both linear and non-linear market relationships. Methods include Vector Error Correction Models (VECM), Time-Varying Parameter Vector Autoregressive (TVP-VAR) models,
Quantile Vector Autoregression (QVAR), Threshold Autoregressive (TAR) and Momentum TAR models, alongside the Diebold and Yilmaz connectedness approach. Monthly time-series data (September 2009–May 2019 (ECI,ECII,ECII)
and January 2011–January 2023(ECIII)) from key soybean markets were analysed: Chicago Futures, Rotterdam Port, Paranaguá Port, Rosario markets, and Chinese
domestic and futures markets. Moreover, a range of agricultural and energy commodities were studied.
Results reveal a highly efficient and integrated global soybean market with rapid adjustments to long-term equilibrium despite geopolitical disruptions. Chicago
Futures emerges as the primary price leader, though traditional methods struggled to detect structural breaks during market shocks. Overall price transmission is
symmetric in these studied markets. The TVP-VAR analysis uncovered evolving market hierarchies, with Paranaguá and Rosario Futures emerging as new price leaders alongside Chicago. The multi-commodity QVAR analysis demonstrated that
soybeans consistently drive price spillovers across agricultural, energy, and input markets.
This research offers crucial insights for policymakers and market participants navigating an increasingly volatile global commodity landscape. The findings indicate that, although established market mechanisms remain resilient even in the face of trade disputes or armed conflict, the geographic centres of price discovery are shifting. Consequently, it is necessary to adopt adaptive risk management strategies to maintain market stability amid ongoing geopolitical uncertainties
Linking geographical, agricultural, and dietary factors to human selenium intake and rice selenium concentration: a Taiwanese case study
No full textSelenium (Se) deficiency amongst human populations is common globally, especially among vegetarians and vegans relying solely on soil-uptake by plants. This study aims to evaluate the potential of Se deficiency in plant-based diets and investigate the relationship between Se in locally-grown vegetative food and soil properties. Representative market food produced in different seasons and locations and paddy field rice and soil samples across Taiwan were collected and Se analyzed. Results showed that the vegetative foods in Taiwan generally have higher Se than those in the U.S., but rice Se levels are significantly lower than those reported in the U.S., India, and mainland China. Food type and cultivation location exert greater influence on Se content than seasonal variation. Rice from Northwest Taiwan (Hsinchu and Taoyuan) contains four times more Se than Southeast regions, likely due to lower soil phosphorus (P) and higher iron/aluminum hydroxides, which enhance Se uptake. Over-application of P fertilizers (over 50 % of rice fields have soil M3-P >50 mg kg−1) correlates with reduced Se absorption in rice, as higher soil total P (>1500 mg kg−1) or M3-extractable P (>150 mg kg−1) decreased Se uptake. For vegans in Taiwan, dietary Se intake should be increased roughly fourfold to meet the recommended 55 μg day−1 and stay below toxicity limits of 400 μg day−1. This can be used as a reference for future Se biofortification research for Taiwanese and/or recommendations for inclusion of seaweeds or supplements, ensuring adequate Se intake across dietary preferences, thus improving public health outcomes
An agroecological assessment of uncrewed aerial vehicle spraying in Greek viticulture
Get PDFSpraying pesticides with uncrewed aerial vehicles (UAVs) in European viticulture is currently only allowed when there are no viable alternatives or if it provides environmental and human health benefits. Using Greece as a case study, this analysis investigated the agroecological performance of UAV spraying in comparison with land-based pesticide application. A multi-objective linear programming model assessed farmer preferences for spraying pesticides with ground equipment or a UAV. Farmers concerned with non-economic goals preferred UAV targeted pesticide application, while production-orientated farmers favoured ground spraying. Depending on disease pressure, UAV spraying generated annual savings of €278–377 ha-1 on a flat vineyard compared to a trailed vine sprayer and €367–538 ha-1 on a steep-slope vineyard compared to a backpack sprayer. However, the estimated costs of custom-hiring UAVs in Greece made UAV spraying less profitable except in conditions of simultaneous extreme labour scarcity and high disease pressure on the steep-slope vineyard. UAV aerial broadcast had an environmental impact comparable to ground spraying, but UAV spot-spraying mitigated ecotoxicological risks of pesticide use by 46–50 %. Both UAV spraying methods substantially reduced human exposure to pesticides. In current regulation, UAV aerial broadcast would only be allowed in steep-slope viticulture if seasonal labour was unavailable. UAV spot-spraying could be permitted on both vineyards, but it would be economically feasible if hiring fees were €43–49 ha-1. The study concludes with recommendations to promote UAV spraying adoption among European farmers thereby contributing to the EU objectives to halve pesticide use and risk while potentially resolving labour availability challenges on abandonment-prone vineyards
Resilience of food supply systems to sudden shocks: A global review and narrative synthesis
Get PDFGlobal food supply systems (FSS) are increasingly tested by sudden shocks such as pandemics, geopolitical conflicts, and extreme weather events, that demand adaptive and transformative responses. This systematic review analyses 26 empirical studies published between 2016 and 2023, each examining an abrupt disruption in FSS. Of these, 22 focus on exposure to COVID-19 and four on natural disasters. Findings reveal that the most resilient food supply systems are those that combine strong operational, relational, and structural attributes with well-developed capacities at each shock phase (pre-, during-, and post-). These elements, taken together, not only enable effective recovery (returning to near-normal function) but also foster adaptation (dynamic adjustments to new conditions) and transformational shifts (permanent, beneficial reconfigurations) whenever disruptive events strike. However, many studies indicate that the capacity to “bounce forward” remains limited: short-term coping actions are often not converted into long-term structural reforms. This gap is particularly noticeable in settings with weak policy frameworks or resource constraints, undermining broader resilience gains. Although FSS often exhibit significant adaptability during disruptions, deeper transformation requires sustained efforts and alignment among governmental, private-sector, and community actors. The integrated framework of resilience proposed in this review clarifies how attributes underpin capacities that, when activated through concrete actions, shape resilience outcomes. By emphasising both short-term coping and long-term systemic change, stakeholders can strengthen future resilience strategies across diverse FSS contexts. Enhanced conceptual clarity, multi-scalar approaches, and expanded empirical evidence are crucial for guiding policy and practice, ultimately enabling FSS to withstand and learn from sudden shocks
Performance, metabolism and nitrogen use efficiency in dairy cows fed low protein, legume silage-based diets: a systematic review and meta-analysis
Get PDFThe primary focus of low CP diets and the inclusion of legume silages for dairy cows is to decrease feed costs and mitigate the environmental impact of milk production. This systematic review and meta-analysis were conducted to evaluate the effects of dietary CP level on the performance, metabolism, and N use efficiency (NUE; g milk N output/kg N intake) of dairy cows fed legume-based rations. A total of 36 production trials with 102 treatment means were included, and the effect of dietary CP level was estimated using the raw-mean difference between control (high CP) and low CP diets. Publication bias was examined using Begg’s and Egger’s tests. Meta-regression and subgroup analyses were performed to explore the heterogeneity of the response variables. Reducing dietary CP from 171 g/kg DM to 145 g/kg DM in forage legume-based diets resulted in decreased DM intake (−0.62 kg/d), milk yield (−1.41 kg/d), milk protein (−0.22 g/kg), milk urea N (MUN; −3.47 mg/dL), plasma urea N (−1.85 mmol/L) and condition score (−0.03) in dairy cows. Similarly, nutrient intake, diet digestibility, total urine output, N excretion through milk, urine and faeces, urine N/total N intake, rumen ammonia-N and molar proportion of butyrate were decreased (P < 0.05) in cows receiving low CP diets compared with those fed the control. In contrast, low CP diets increased (P < 0.05) the faecal N/total N intake, NUE, and plasma content of non-esterified fatty acids. Subgroup analyses revealed that the effect size of DM intake, milk yield, MUN, urinary N excretion and rumen ammonia-N content had less of a negative impact (P < 0.05) when cows received dietary CP levels of 140–155 g/kg DM than < 140 g/kg DM. The inclusion of rumen-protected methionine in low CP diets increased (P = 0.04) DM intake and tended to improve (P = 0.08) the milk protein content of dairy cows. Feeding lucerne silage-based low CP diets showed an improvement (P < 0.05) in apparent diet digestibility but reduced milk yield (−1.46 kg/d) relative to red clover silage-based rations. The inclusion rate of legume silages in low-CP diets beyond 40% of the forage DM reduced (P < 0.01) DM intake and milk protein content. We conclude that legume silage-based low CP diets enhance NUE but have adverse effects on dairy cow performance that can partially be mitigated by including rumen-protected methionine and limiting their proportion in the forage component of the diet
Inflorescence size predicts host–symbiont conflict in monoecious fig–wasp mutualisms
Get PDFIn monoecious fig–wasp mutualisms (Ficus; ~350 spp.), tiny wasps obligately pollinate fig-tree inflorescences (‘figs’). Although pollination enables seed production, wasp symbionts also oviposit into flowers, replacing potential seeds with wasp offspring. Consistently across Ficus, ~40–60% of developed flowers produce seeds. Although several processes are probably involved, a general explanation for why wasps do not exploit more flowers has been elusive. However, interspecific scaling between host–symbiont reproductive traits suggests that as figs become larger across Ficus, the increase in wasp-eggs-per pollen-receptive fig will fail to match the increase in flower numbers. The potential for wasps to exploit hosts should thus decline due to an increasing excess of flowers. We tested these predictions, which were upheld, using data from 23 fig–wasp mutualisms from four continents. As fig size increases across Ficus, wasp egg-to-flower ratios, a measure of host–symbiont conflict of interest, declines, but the likelihood of a wasp egg successfully becoming an adult offspring increases. Host–symbiont conflict of interest thus varies systematically across Ficus due to variable relationships between key mutualist reproductive traits and fig size. We suggest that mutualism stability is more dependent upon mechanisms curtailing wasp flower exploitation in systems with small figs, and on preventing high foundress numbers in those with large figs
An Apple a Day Does Not Keep the Weevils Away: Enhancing Vine Weevil Monitoring With Fruit‐Based Volatiles
Get PDFVine weevil (Otiorhynchus sulcatus Fabricius; Coleoptera: Curculionidae) is an economically important pest of soft fruit and ornamental crops worldwide. Despite extensive research over three decades, the development of an effective semiochemical lure to improve monitoring for this pest remains a challenge. This study investigated the behavioural and electrophysiological responses of adult vine weevils to apple sauce volatiles under laboratory conditions, using Y‐tube olfactometer bioassays and headspace analysis using gas chromatography coupled to mass spectrometry (GC–MS) and GC coupled to electroantennographic detection (GC‐EAD). In Y‐tube bioassays, more adults selected the olfactometer arm containing apple sauce volatiles compared to the control arm at lower doses (0.1, 1 and 10 g) but not at higher doses (20 g). Thirteen compounds were identified in volatiles collected from apple sauce, with the major components being furfural and sorbic acid. Consistent electrophysiological responses were recorded to (E)‐2‐heptenal, 1‐hexanol, (Z)‐3‐hexenol and (E)‐2‐hexenol. The behavioural response of vine weevil adults to refuges baited with semiochemical lures was also tested under glasshouse conditions. In this scenario, a greater proportion of individuals were recorded in refuges baited with apple sauce compared to unbaited refuges. A similar behavioural response was also recorded when refuges were baited with a combination of apple sauce and Fortune's spindle ( Euonymus fortunei (Turcz.) Hand.‐Maz.; Celastrales: Celastraceae) compared to those that were unbaited or individually baited with Fortune's spindle or apple sauce. This study indicates that apple sauce positively influences positively vine weevil behaviour and could serve as a basis for developing a novel lure for improved monitoring
Autonomous regenerative agriculture: Swarm robotics to change farm economics
Get PDFRegenerative agriculture (RA) with mixed cropping is suggested to promote soil health. Combining crops with livestock adds another element of the RA paradigm. The simplest mixed cropping system is strip intercropping but use on conventional mechanized farms is limited by higher labour and capital investment. The objective of this study was to assess the comparative competitiveness of RA practices with and without livestock operated using conventional mechanized farm with human drivers and swarm robotics. Modelling livestock component considered intensive cattle feed using harvested forage because grazing in narrow strips is difficult. The profit maximizing optimization model of a 500 hectare (ha) British West Midlands farm found that per annum profitability of regenerative strip intercropping system was £56.88 ha−1 higher for farm operated using smaller swarm robotics than farm operated using smaller conventional mechanization with human drivers. The conventional whole field sole cropping system operated using larger machines with human drivers returned £128.36 ha−1 per annum less than regenerative strip intercropping operated using swarm robotics. Adding livestock component with crop only regenerative strip intercropping system resulted negative return per annum (- £26.72 ha−1). The added labour for livestock rearing, forage and manure transport, and higher machine costs challenged competitiveness of regenerative system with livestock. This reinforcing the need to more completely automate public road transport and intensive livestock rearing. Results indicate that swarm robotics have potential to change the cost calculus of RA practices, while livestock integration needs careful cost-effective designs to reinforce farm profitability