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Describing blood acid-base response in dogs with acute haemorrhagic diarrhoea syndrome using three different methods
Michaletos, Anthea Francis (University of Pretoria, 2025-09)
Objective: To describe blood acid-base response in dogs with acute haemorrhagic diarrhoea syndrome (AHDS) using three different methods of analysis. Hypothesis: Dogs with AHDS have increased unmeasured strong anions compared to healthy dogs. Design: Prospective, observational study. Setting: Private referral hospital. Animals: A total of 20 dogs used in two groups as follows: 10 healthy age-, weight- and breed-matched dogs and 10 dogs with AHDS. Interventions: Blood that was collected from healthy dogs were used to establish an expected normal range (minimum and maximum limits of the ranges were calculated as mean ± 2 standard deviations). Jugular venous blood, AHDS index scores (0 – 3: insignificant disease; 4 – 5: mild AHDS; 6 – 8: moderate AHDS; 9 – 18: severe AHDS) and intravenous fluid infusion volumes (mL/kg) were collected at presentation (0H) and then at set hour-intervals post presentation (4H, 8H, 12H, 16H, 20H, 24H, 36H, 48H and 60H). Blood was analysed to measure or calculate acid-base variables used in three different methods of analysis: 1) traditional, 2) Stewart theory, and 3) semi-quantitative theory approaches. Longitudinal data were compared using a general lineal mixed model with post-hoc comparisons using Dunnett's method (control variable: values at 0H) and significance was P < 0.05 and data were reported as median (minimum – maximum). Measurements and main results: The pH, at 0H, was 7.31 (7.22 – 7.49) and classified as acidaemic with a wide anion gap of 24.6 (13.1 – 27.6) mmol/L because of a raised venous carbon dioxide tension [48 (26 – 51) mmHg], negative base excess of extracellular fluid [-5.4((-8.0) – (-2.4)) mmol/L] and acidaemic lactate effect [-3.5 ((-5.4) – (-1.2)) mmol/L]. The pH normalised by 4H (P < 0.0001) in response to fluid administration where 37 (29 – 63) mL/kg was given over the 4-hour period. Whereas the AHDS clinical index score was classified as ‘insignificant disease’ by 48H. The pH remained within normal reference intervals until 60H and fluid rates were 3 mL/kg/hour from 8H onwards. The bicarbonate and haemoglobin buffer systems played a role in blood acid-base homeostasis. Conclusions: The acidaemia at presentation in dogs with AHDS was related to hypovolaemia and all derangements were corrected by fluid resuscitation. All three methods of analysis were useful in interpreting the complex interplay between acidifying and alkalinising effects and blood buffers.
Mycotoxins : an ongoing challenge to food safety and security
Yilmaz, Neriman; Verheecke-Vaessen, Carol; Ezekiel, Chibundu N. (Public Library of Science, 2025-11-10)
Mycotoxins have influenced human and animal health for centuries, often with serious and sometimes deadly consequences. The earliest known cases are outbreaks of ergotism in medieval Europe, caused by alkaloids from Claviceps purpurea growing on rye. These epidemics, called “St Anthony’s fire”, produced convulsions, gangrene and death. Ergot-infected grain has also been suggested as a possible factor behind the symptoms recorded during the Salem witch trials in 1692. During the Second World War, people in Russia consumed overwintered grain infected by trichothecene-producing Fusarium species. This led to the alimentary toxic aleukia epidemic, one of the best-documented examples of human mycotoxicosis. Such outbreaks demonstrate the longstanding impact of mycotoxins on societies.
Trends in sustainable agricultural supply chain management
Bai, Yan; Jiang, Dongdon; Pretorius, Leon (Czestochowa University of Technology, 2025)
Sustainability in Agricultural Supply Chains (ASC) is an emerging interdisciplinary field that has recently garnered increasing attention from scholars. This paper provides a comprehensive review of the current state of research in sustainable ASC based on an extensive analysis of Scopus and Web of Science databases. The study maps the research landscape by examining key aspects such as time distribution, journal trends, research fields, quantitative methods, and other bibliometric factors. The paper highlights research hotspots and identifies future trends, with a particular focus on (1) sustainable dimensions in ASC, (2) intelligent ASC, (3) the traceability of agricultural products, and (4) the role of e-commerce in enhancing agricultural product distribution. The novelty of this study lies in its systematic approach to bridging the gap between research on sustainable supply chain systems and ASC, areas that have been largely studied independently. By analyzing a broad range of studies, this paper provides an integrated perspective that fosters a deeper understanding of sustainable ASC systems. The results show a significant upward trend in publications, indicating growing scholarly interest in sustainable ASC. The study also reveals a gradual shift towards focusing on sustainable value chains as critical for food security. Additionally, the paper synthesizes various sustainable dimensions, mathematical models, and solution approaches for ASC management. This review proposes emerging research trends in sustainable ASC management and offers suggestions for future studies. It aims to stimulate a more comprehensive and interdisciplinary research agenda, particularly in the integration of sustainability, technology, and traceability within ASC.
Strategies and responses to the effects of climate change on health systems in Sub-Saharan Africa : a scoping review protocol
Chimatiro, Chancy Skenard; Mianda, Solange; Hajison, Precious L.; Lembani, Martina (Public Library of Science, 2025-08-06)
BACKGROUND : Climate change is recognized as the greatest global health threat of the 21st century. Projections suggest that the Sub-Saharan African region will face more consequences of climate change than any other region globally. The health systems within the region have been affected by the negative effects of climate change. Mapping strategies and responses used in the region to address the effects of climate change on health systems in Sub-Saharan Africa could be a starting point for understanding evidence-based decision-making to inform best practices. METHODS : This scoping review will follow the methodological framework by Arksey & O'Malley. A wide range of databases will be searched to identify articles published on the strategies and responses to the effects of climate change on the health systems in Sub-Saharan Africa. Only peer-reviewed articles (original quantitative and qualitative studies, mixed methods, systematic reviews, editorials, and commentaries) published in English Language between 2010 and 2024 will be reviewed. All Book chapters and the grey literature (dissertations, conference proceedings, abstracts, reports) and publications primarily focusing on climate change strategies and responses without effects on health systems will be excluded. Covidence software will be used during study selection, data extraction, and summary. Deductive thematic analysis will be performed using predetermined themes from the objectives. DISSEMINATION : The results of this scoping review will be disseminated at local and international research conferences. Furthermore, the findings will be published in open-access journals targeting different audiences. The findings will also be shared with the Ministry of Health in Malawi for possible policy considerations.
Disposable diaper use and perception of health and environmental risks in a rural community from Bushbuckridge, South Africa
Lowe, Army L (University of Pretoria, 2024-10)
Littering of disposable diapers is a problem with One Health implications and has been identified as an issue within the Mnisi community, a rural area within Bushbuckridge, South Africa. Several environmental and public health related concerns arise from this, including contamination of waterways used by animals and people with human waste, scavenging by domestic and wild animals, and the aesthetic impact on the environment. The aim of this study was to gain an understanding of the use and sanitation practices associated with disposable diapers, with the ultimate goal of identifying possible community-led initiatives and solutions which can be used for training and education. Focus group discussions were conducted within the community which included a participatory mapping exercise used to map general diaper disposal sites. Focus group data was analyzed according to three themes: decisions and factors around diaper use and disposal, perceptions of impact and health risk of diaper use for people and animals, and barriers and solutions for proper disposal. Most participants used disposable diapers and disposed of them within the environment because they lacked access to municipal waste collection. Regarding decisions around diaper use, common factors discussed were convenience, social perception and beliefs, cost, water access, and diaper disposal logistics. Convenience and societal perception and beliefs were determined as key factors behind diapering choices, and both a gender and a generational divide was revealed. Participants express general understanding of negative impacts associated with diaper disposal, but knowledge gaps exist, notably regarding water pollution and pathogen spread, that could be a focus of educational campaigns. Regarding solutions, participants proposed the provision of a central collection point as well a return to reusable diapers, each of which has its own considerations and hurdles. Any interventions should retain the perceived convenience factor of disposable diapers and be implemented on a community rather than individual basis. Solutions should be multifaceted, involve opportunities for community collaboration amongst all ages and genders, and should also engage local leadership. Focus groups should be considered as the first steps towards continued discussions amongst stakeholders.