Research Articles (Paraclinical Sciences)

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Eradicating infectious disease : can we and should we : a critical examination
Mitchell, Emily P.; Pathirannehalage, Sunil-Chandra Narapity (Elsevier, 2025-12)
To highlight the possible consequences of eradicating disease, relevant literature on the intended and unintended consequences of disease eradication was reviewed. Though resource-intensive, eradication is often more cost-effective than long-term control. Global health leaders pursue eradication when the benefits promise lasting public health gains and transformative impact, as in the case of smallpox, guinea worm, and rinderpest. Competitive release, where other pathogens with similar transmission modes or tissue tropism expand into the vacated niche, is discussed. One underlying principle of the One Health approach to understanding emerging infectious diseases is that human, animal, and environmental health are driven by a complex interplay of ecological, behavioral, and socioeconomic factors. The law of unintended consequences means that whenever humans alter one factor, a completely unexpected event may occur. This complexity should be kept in mind in the formulation of any disease eradication or control program.
Comparative genomics of diverse Escherichia coli O157:H7 strains to characterize plasmids, prophages, virulence, and antimicrobial resistance genes
Gambushe, Sydney Menzeko; Idowu, Peter Ayodeji; Zishiri, Oliver Tendayi (Elsevier, 2026-12)
Plasmids play a critical role in bacterial evolution and represent major drivers of the emergence and dissemination of antimicrobial resistance. As primary mobile genetic elements (MGEs), plasmids facilitate the horizontal transfer of resistance determinants alongside genes associated with virulence, metabolic functions, and broader adaptive advantages. Recent studies have further highlighted the importance of conjugative plasmids, such as IncI1-like elements, in mediating the spread of extended-spectrum β-lactamase (ESBL) genes and other clinically relevant traits across diverse bacterial populations. Whether the recurrent detection of these plasmids is coincidental or reflects unique genetic features that enhance their capacity for transmission remains an important question in microbial genomics. In this context, the present study analyses complete genome sequences and whole-genome maps of Escherichia coli O157:H7 strains to characterize their antimicrobial resistance genes, virulence-associated loci, prophage content, and plasmid profiles. Publicly available sequences from the NCBI GenBank repository were examined using comparative genomic tools, including BRIG, VirulenceFinder, ResFinder, PlasmidFinder, and PHASTEST. This work also underscores the limited availability of whole-genome data for E. coli O157:H7 and O157:H7NM in developing regions, particularly within African countries, highlighting the need for expanded genomic surveillance. Comparative analyses revealed that most strains displayed high genomic similarity to the reference Sakai strain, with relatively few missing regions, although a subset exhibited reduced homology marked by numerous gaps. Prophages, bacteriophages integrated into the bacterial genome, were found to contribute substantially to genomic diversity, influencing virulence potential, antimicrobial resistance, and patterns of horizontal gene transfer. These findings emphasize the complex role of mobile genetic elements in shaping the evolution of E. coli O157:H7 and reinforce the importance of continued genomic sequencing to further elucidate the pathogen's diversity and adaptive mechanisms. HIGHLIGHTS • Comparative genomics was used to analyze diverse E. coli O157:H7 strains. • Plasmid, prophage, virulence, and antimicrobial resistance profiles were characterized. • IncI1-like and other plasmids carrying key AMR and virulence genes were identified. • Prophages contributed substantially to genomic diversity and adaptive potential.
Pathological findings in 61 free-ranging leopards (Panthera pardus) from the Greater Kruger National Park, South Africa. Part One : parasites
Mitchell, Emily P.; De Klerk-Lorist, Lin-Mari; Buss, Peter; Reininghaus, Bjorn; Bengis, Roy (Elsevier, 2026-04)
The Kruger National Park and surrounding protected areas in South Africa are home to a core unmanaged population of approximately 1,200 free-ranging leopards (Panthera pardus). Leopard populations outside of protected areas are in decline due to trophy hunting, habitat fragmentation and human-wildlife conflict. Apart from single descriptions of parasites detected by faecal or necropsy examinations and serology, very little information is available on parasitic conditions in free-ranging leopards. This paper provides baseline information on parasites in free-ranging leopards that may be relevant to the management of threatened populations of leopards outside of the Greater Kruger National Park (GKNP). Opportunistic field necropsies with routine histological examination of formalin-fixed tissues and, where possible, identification of helminths preserved in ethanol or by histology were performed on 61 free-ranging leopards in the GKNP between 1998 and 2023 for long-term disease monitoring. Most (52/61, 85%) of these leopards were euthanized because they attacked or killed a person or had severe traumatic injuries or disease. Five leopards died during anaesthesia performed to evaluate traumatic injuries or tuberculosis status. Three animals died naturally due to traumatic injuries and one due to electrocution on an electric fence. Parasitic disease was seen in similar numbers of males (n = 29) and females (n = 23) and in animals ranging from 1 to 16 years old. Common conditions included myocardial hepatozoonosis (34/61, 56%), gastroduodenitis due to Cylicospirura pardalis (31/61, 51%), verminous pneumonia attributed to metastrongyles (14/61, 23%) and skeletal muscle sarcocystosis (17/61, 28%). Single cases of infestation with Dirofilaria sudanensis, Armillifer armillatus and Linguatula serrata were recorded. In the majority of these free-ranging leopards, even heavy parasitic infestations were associated with minimal inflammation and were likely subclinical. However, two leopards had gastric outflow obstruction due to C. pardalis lesions, two had severe mange and one had severe myocarditis due to hepatozoonosis, which may have significantly affected the health of the affected animals. The factors that trigger the transformation of common subclinical parasitic conditions to potentially life-threatening disease require further elucidation.
The cytotoxic effects of a single and combined exposure to the mycotoxins, deoxynivalenol and zearalenone, on a rat Leydig cell line (LC-540)
Ibrahim, Mohammed I.A.; Lensink, Antoinette, V.; Botha, C.J. (Christoffel Jacobus) (Elsevier, 2026-03)
Deoxynivalenol (DON) and zearalenone (ZEA) are among the most prevalent mycotoxins synthesized by Fusarium species, with 60 % and 80 % prevalence in grains containing mycotoxins, respectively. These mycotoxins often co-contaminate feedstuffs and induce male reproductive toxicity. This study investigated in vitro cytotoxicity, the structure of selected cytoskeletal proteins, mitochondrial morphology, lysosomal activity, and ultrastructural changes associated with individual and combined DON and ZEA exposure in rat Leydig cells (LC-540). Deoxynivalenol (IC50: 2.66, 0.50, and 0.44 μM) induced higher cytotoxicity than ZEA (IC50: 117.0, 69.1, and 34.4 μM) after 24, 48, and 72 h, respectively. Combined DON + ZEA exposure revealed concentration- and time-dependent cytotoxic effects that were synergistic at low concentrations (0.125 + 10 μM), but additive or antagonistic at higher concentrations (2 + 30 and 5 + 50 μM). Microscopic analysis revealed both mycotoxins disrupted F-actin and β-tubulin, impaired mitochondrial morphology, and increased lysosomal acidification. Ultrastructurally, marked cellular alterations included mitochondrial damage, autophagosome formation, and apoptosis. The observed cytotoxicity, disruption of cytoskeletal proteins, and mitochondrial damage in the Leydig cells may play a role in clarifying the male reproductive toxicity induced by DON and ZEA or their co-exposure. HIGHLIGHTS • DON and ZEA induced time- and concentration-dependent cytotoxicity in rat Leydig cells (LC-540). • Combined DON and ZEA exposure showed synergistic effects at low concentrations in LC-540 cells. • DON and ZEA disrupted F-actin and β-tubulin cytoskeletal proteins in LC-540 cells. • DON and ZEA exposure caused mitochondrial damage and increased lysosomal acidification in LC-540 cells. • Combined mycotoxin exposure induced autophagy and apoptosis in LC-540 cells.
The approximate subcutaneous LD50 and associated lesions induced by Ivalin, extracted and purified from Geigeria aspera Harv., in Sprague-Dawley rats
Locke, Sara Lindsey; Botha, Christo; Clift, Sarah Jane; Lensink, Antoinette V. (MDPI, 2026-02)
“Vomiting disease” in ruminants is one of the most economically significant phytotoxicities in South Africa and is caused by chronic ingestion of sesquiterpene lactone compounds present in plants of the Geigeria genus. Affected livestock demonstrate mortality due to actin and myosin damage in the striated musculature; however, a validated parental-exposure laboratory animal model would be useful for further study of the toxicodynamics. We exposed Sprague–Dawley rats to ivalin in a sequential dosing procedure and evaluated clinical signs, mortality, histopathology and muscle ultrastructure. Three of the five exposed rats died acutely, and a maximum likelihood estimate method was used to calculate a Median Lethality (LD50) of 135.4 mg/kg Body Weight (BW). Striated muscle in exposed rats showed only minimal and inconsistent histopathological and ultrastructural changes. Subcutaneous ivalin exposure causes acute mortality with minimal muscle pathology, contrasting with the more protracted muscular disease seen in ruminants after plant ingestion. This suggests toxicity by parenteral exposure is due to another mechanism, most likely mitochondrial energy pathway disturbances. Whilst subcutaneously exposed rats do not appear to provide a suitable model for oral sesquiterpene lactone exposure in ruminants, this study provides a starting dose for further investigation of plant extracts in both species.
Physicochemical, microbiological and sensory evaluation of plant-based meat analogs supplemented with phenolic extracts from olive mill by-products
Nichita , Adina; Sordini, Beatrice; Al-Olayan, Ebtsam; Esposto, Sonia; Costanzi, Egidia; Cenci-Goga, Beniamino Terzo; Popa , Mona Elena; Servili , Maurizio; Veneziani, Gianluca (MDPI, 2025-09-26)
The bioactive properties of a phenolic extract (PE) obtained from olive mill vegetation water (OVW) in powder formulation were utilized to enrich a meat analog composed of lentils and champignon mushrooms. The primary phenolic compounds in this extract were oleacein, verbascoside, and hydroxytyrosol. The effects on the final product were assessed over eight days of storage at 4 °C ± 2 under 12 h of light. The control samples were compared with two meat analogs enriched with ascorbic acid (AA) at 5 g kg−1 and one enriched with PE at 30 g kg−1. The physicochemical parameters (pH, aw, color, texture, and total phenol content), antioxidant activity, microbial assessment, and sensory evaluations of meat analog samples were evaluated at three different time points (T0, T4, T8) during shelf life. The PE-enriched meat analogs maintained a relatively high and stable phenolic concentration throughout their shelf life, significantly enhancing the antioxidant activities of the final product. The addition of PE also influenced the growth of Enterococcus spp., Lactococcus spp., and Lactobacillus spp. during storage. The results of the triangular test indicated perceptible differences between AA and PE meat analogs. Meanwhile, the quantitative descriptive analysis (QDA) emphasized notable enhancements in odor and texture characteristics for PE-enriched samples. Plant-based meat analogs can benefit from the effective use of PE (antioxidant and sensory properties), supporting the sustainable reuse of olive oil by-products.
Euthanasia methods in invertebrates : a critical narrative review of methodological and welfare standards
Bakker, Jaco; De la Garza, Melissa A.; Morel, Margot; Outwater, Anne H.; Chipangura, John Kudakwashe; Stumpel, Job B.G.; Vercammen, Francis; Lewbart, Gregory A.; Nederlof, Remco A. (MDPI, 2026-01)
Invertebrates are increasingly consumed and kept as pets, research models, and in zoological exhibits, creating a growing need to better understand their clinical management and welfare. However, the knowledge regarding nociception, pain perception, and euthanasia in invertebrates remains limited, and standardized protocols are largely absent. Current guidelines are incomplete, often anecdotal, and omit several major invertebrate phyla. To address this gap, we conducted a narrative review of the literature, aiming to critically evaluate existing euthanasia methods, associated welfare implications, and opportunities for refinement. The amount of peer-reviewed species-specific literature is limited and scattered. In addition, most described methods are insufficiently studied and/or do not align with our definition of euthanasia. Based on the available literature, and to provide practical guidance despite these limitations, we propose a two-step approach to invertebrate euthanasia. The first step consists of inducing anesthesia to achieve loss of responsiveness, followed by a second step; a terminal procedure involving physical or chemical destruction of the brain or major ganglia. Our review focuses on the application of this two-step approach. The effectiveness and humaneness of euthanasia techniques vary considerably across taxa and life stages. Substantial further research is required to validate and optimize humane end-of-life procedures for diverse invertebrate species. SIMPLE SUMMARY Euthanasia is an inevitability in the veterinary profession. The method of euthanasia used must rapidly induce loss of consciousness and death, be effective, and minimize the pain, fear, and distress experienced by the animal. Interference with euthanasia objectives, e.g., research, should be avoided if possible. Moreover, the method of euthanasia should be simple enough to be performed effectively by competent individuals. The availability of peer-reviewed literature specific to invertebrates is scattered and limited. Based on the available scientific evidence, the most effective methods of invertebrate euthanasia entail a two-step approach. Here, the first step consists of the induction of anesthesia to achieve loss of responsiveness, followed by a terminal second step, involving physical or chemical destruction of the brain or major ganglia. The effectiveness and perceived humaneness of euthanasia techniques vary considerably across taxa and life stages.
Methionine, threonine and glutamic acid adapted pathways in captive cheetahs on a glycine-supplemented diet
Van Boom, Kathryn Merle; Kohn, Tertius Abraham; Tordiffe, Adrian Stephen Wolferstan (Springer, 2025-04-23)
BACKGROUND : Captive cheetahs are prone to a range of unusual diseases potentially linked to unnatural diets high in muscle meat and low in collagen-rich animal fibre. In the wild, cheetahs typically eat whole prey diets not easily replicated in a captive setting. Glycine is the most abundant amino acid in collagen with a key role in several metabolic pathways such as collagen biosynthesis. Several recent studies suggest that endogenous glycine production may be limited in several species. OBJECTIVES : Using untargeted 1H- nuclear magnetic resonance, the metabolic changes in the urine and serum of 10 adult captive cheetahs on a glycine-supplemented diet were investigated. METHODS : Cheetahs were fed either a meat only (control) or glycine-supplemented meat diet (30 g glycine per 1 kg meat) for four weeks, followed by a four-week cross-over. Urine and blood samples were collected at baseline and after each intervention. RESULTS : A total of 151 and 60 metabolites were identified in the urine and serum, respectively. Specifically, dimethylsulphone, proline, fructose, dimethylamine, trimethylamine, pyroglutamic acid, 1,3-diaminopropane, dihydrothymine, methylmalonic acid and pimelic acid contributed to metabolome differences in the urine. In serum, glutamic acid, threonine, α-aminobutyric acid, glucose-6-phosphate, ethanolamine, methionine and propionic acid were highlighted. These metabolites play various metabolic roles in energy production, immune function, protein and collagen biosynthesis or as products of gut microbiome fermentation. CONCLUSION : Glycine supplementation influenced threonine sparing, pyrimidine biosynthesis pathways and bacterial fermentation products, although the implications of these findings on the health of captive cheetahs is unknown. Future studies should use a targeted approach to further elaborate on these pathways.
Probiotics as sustainable alternatives to antibiotic growth promoters : mechanisms, applications, and future perspectives in livestock production
Idowu, Peter Ayodeji; Mbambalala, Lwando; Idowu, Adeola Patience (Dr. Nasir Akbar Mir, 2025-11-21)
This narrative review systematically summarizes the current knowledge about probiotics as scientifically defined alternatives to conventional antibiotic growth promoters (AGPs) in modern livestock farming. Globally, there is an increase in demand for AGP-free livestock due to growing threat of antimicrobial resistance. Although ample literature is available on efficacy of probiotics as AGP alternatives, there is a paucity of comprehensive data on strain-specific modes of action, effective dose regimens, and standardized application protocols across wide variety of livestock species. Probiotics exert complex antimicrobial mechanisms, including direct pathogen antagonism, gut microbiome modulation, intestinal barrier enhancement, immune system stimulation, and metabolic optimisation. In ruminants, poultry, pig, and rabbits, the application of probiotics has repeatedly shown improved growth performance, increased resistance to disease, better breeding performance and so on. Most of the literature available shows positive results on rumen fermentation, caecal microbiota composition, nutrient digestibility, and immunological responses. Nonetheless, knowledge gaps remain in the areas of interaction with the environment, production standardisation, and long-term effects of sustainability. Sustainability elements include less development of antimicrobial resistance, reduced environmental impact due to more efficient resource use, and improved economic viability. However, variations in strain-specific probiotic efficacy, environment-dependent outcomes of probiotic applications, and lack of production standardisation remain the challenges. Emerging innovations, such as postbiotics, precision livestock farming integration using AI, Internet of Things, and multi-strain synbiotic formulations offer promising solutions. This review summarises opportunities and challenges associated with probiotic use in livestock production systems and underscores their potential to revolutionise sustainable animal agriculture, as well as deal with serious public health concern of antimicrobial resistance.
The optimisation and application of a novel baseScope™ RNA-ISH assay for the detection of foot-and-mouth disease virus in carrier African buffalo (Syncerus caffer) from South Africa
Henning, Alischa; Odendaal, Lieza; Loots, Angelika Katrin; Quan, Melvyn (Elsevier, 2025-12)
The detection of foot-and-mouth disease is limited to BSL-3 laboratories and its detection in carrier animals require increased test sensitivity. In-situ-hybridisation utilises the propensity of a labelled single-stranded sequence of DNA or RNA to anneal to a complementary target. It can be performed on formalin-fixed tissues and with some of the most recent advances, show an increased test sensitivity. BaseScope™ incorporates an additional signal amplification step, which makes it possible to detect RNA splicing variants, point mutations, small insertions or deletions, and short RNA targets (50–300 nucleotides). This study aimed to adjust and optimise the BaseScope™ assay to detect foot-and-mouth disease virus in a novel, carrier wildlife species, i.e., buffalo. Specific steps were adjusted to attempt to address some of the rigidity involved in the workflow. However, none of the in-house reagents or equipment attempted as an alternative to the original and prescribed workflow was successful. This demonstrates the fastidious nature of this diagnostic modality and the synergistic characteristics of a commercial assay. However, keeping tissues in formalin for up to 7 days and storing cut sections for up to 3 months did not have a negative impact on the results. This further demonstrated the reliability of BaseScope™.
A systematic review of the role of laboratory animal veterinarians in promoting One Welfare
Chipangura, John Kudakwashe; Kanengoni, Arnold Tapera; Nederlof, Remco A.; Bakker, Jaco; Naidoo, Vinny (Sage, 2026-01)
One Welfare is an emerging concept that seeks to integrate the welfare of animals, humans and the environment. This systematic review examines the role of laboratory animal veterinarians in promoting One Welfare within the context of animal use for scientific research. By analysing 65 publications, we explored the diverse roles of laboratory animal veterinarians in advancing animal welfare, supporting human health and promoting environmental sustainability. The reviewed literature described veterinarians’ involvement in areas such as animal welfare oversight, implementation of the Three Rs principles, regulatory compliance and ethical review processes. Several themes emerged that are related to the One Welfare framework, namely: veterinary oversight, welfare assessment and implementation, emotional wellbeing, professional support, and contribution to education and training. The literature highlights the potential need for specialised training in laboratory animal medicine, and outlines the challenges veterinarians encounter regarding ethical considerations and cognitive dissonance in research environments. Based on the identified gaps, we propose measures to reinforce the principles of One Welfare, including interdisciplinary collaboration and the adoption of strategies to safeguard the environment (e.g. the use of composting for minimally-infectious waste and digesters for high-impact waste). Additionally, we recommend establishing institutional sustainability committees to oversee governance and resource management across research institutions.
Definition of meat quality across different cattle breeds
Cenci-Goga, Beniamino Terzo; Costanzi, Egidia; Blasi, Francesca; Ianni, Federica; Tassinari, Marco; Truzzi, Claudio; Karama, Musafiri; El-Ashram , Saeed; Saraiva, Cristina; Martínez-Barbitta, Marcelo; García-Díez, Juan; Zerani, Massimo; Guelfi, Gabriella; Maranesi, Margherita; Grispoldi, Luca; Cossignani, Lina (MDPI, 2025-12-02)
This study investigates the impact of cattle breed on key quality attributes—color, marbling, and tenderness—central to consumer choice. Six different bovine breeds were taken into consideration: German Red Pied, Piemontese, Chianina, Angus, Holstein, and a Polish crossbreed. The muscle taken into consideration was the Longissimus thoracis et lumborum. Colorimetric assessments, marbling evaluations, fatty acid profiling, and tenderness measurements were conducted on meat cuts from each breed. The results revealed that Chianina, Holstein, and the Polish crossbreed exhibited distinct color characteristics, with Chianina displaying notably brighter meat. Angus emerged as the most marbled breed, while Chianina and Piemontese showed lower marbling. Total lipid content was correlated with visible marbling. Tenderness assessments identified Angus and Holstein as the most tender breeds. The study’s findings contribute to a proposed grading scale for color, marbling, and tenderness, offering potential labeling infographics to assist consumers in making informed choices based on individual preferences and needs. These insights underscore the importance of breed-specific information on labels to enhance consumer understanding and facilitate more informed purchasing decisions.
Adipose-specific cytokines as modulators of reproductive activity
Martinez-Barbitta, Marcelo; Biagini, Andrea; Costanzi, Egidia; Maranesi, Margherita; Garcia-Diez, Juan; Saraiva, Cristina; Cenci-Goga, Beniamino Terzo; Zerani, Massimo (MDPI, 2025-12)
Adipose tissue is characterized by specialized lipid handling cells called adipocytes, which function as the primary energy reservoir. Like many other cell types, adipocytes have highly plastic properties, such as the conversion of white adipocytes into brown or beige adipocytes, which produce heat, and pink adipocytes into mammary cells synthesizing and secreting milk. Highly specialized adipose tissue depots are present in various species, such as male orangutans with prominent fat-filled facial flanges indicating hierarchical status, or cetaceans with the melon, a specialized adipose tissue for echolocation. Adipose tissue is now considered a true endocrine organ that regulates various physiological mechanisms through the hormonal secretion of adipokines, which modulate systemic metabolism and physiological processes. In particular, the role of adipokines in the control of the reproductive axis and their participation in the regulation of fertility have been widely reported. This review summarizes the current state of research on the effects of adipose-specific cytokines on the male and female reproductive systems.
First report of a Sporidesmin toxicity (facial eczema) outbreak in a South African dairy herd
Davis, Anthony John; Jordaan, Daniel Du Plessis Scheepers; Myburgh, Jan G. (Medpharm Publications, 2025-03)
Sporidesmin, a toxin released by a saprophytic fungus, Pseudopithomyces chartarum, causes hepatogenous photosensitivity in sheep and cattle, commonly known as Facial Eczema. A recent outbreak in the Eastern Cape Province of South Africa caused significant direct and indirect economic losses to a farmer in the area and highlighted the potential negative consequences of this mycotoxicosis to the dairy industry in this province. The milking herd consisted of 400 cross-bred Jersey/Friesian/Montbilliard cattle. The farmer identified 56 cows showing teat sensitivity/irritability during milking, hypersensitive skin, excessive licking and/or obvious skin lesions on non-pigmented skin areas. Three were culled due to the severity of their skin lesions. Grazing consisted of mixed kikuyu/perennial rye grass pasture under pivot irrigation, alternated with dryland kikuyu/Italian rye and sorghum. Typical clinical signs of severe secondary photosensitivity (skin inflammation and hypersensitivity to touch), very high serum concentrations of Gamma-Glutamyl Transferase (GGT 2143-5177 IU/L) and detection of large numbers of spores on grazed planted pastures supported the clinical diagnosis. Supplementation of zinc oxide (ZnO) powder at 12g per 500 kg cow dosed individually over the concentrates fed in the dairy, effectively reduced the incidence of new cases within two to three weeks. Weight loss, a decrease in milk volume and solids, and increased somatic cell counts were observed during this outbreak. One of these parameters, milk volume loss, was quantified by comparing the financial records of the four years preceding the outbreak to the production figures during the outbreak. The farmer lost approximately R1.5 million in milk volume during this outbreak (November 2020 - April 2021). Long term consequences were also apparent: the culling rate within the clinically affected group of 53 cows was more than 50% higher than the rest of the herd over the following two years. This case study highlights the urgent need to investigate the prevalence and potential economic impact of Sporidesmin Toxicity on the South African pasture-based dairy industry.
Phytochemical profiling and in silico prediction of interactions between Artemisia afra Jacq. ex-Wild, Catharanthus roseus (L.) G. Don and CYP2B6 enzyme
Nghilokwa, Emma T.; Petzer, Jacobus P.; Pheiffer, Wihan; Hassan, Ibrahim Zubairu; Hayeshi, Rose K. (Springer, 2025-10)
Understanding herb-drug interactions is important due to the increasing use of herbal medicines alongside conventional drugs. These interactions can alter the pharmacokinetic properties of drugs, potentially causing subtherapeutic effects or adverse reactions. Artemisia afra and Catharanthus roseus, two traditional African plants used separately to treat malaria, are rich in phytochemicals and may be co-administered with the antimalarial drug artemether. This study aimed to identify the phytochemical compounds present in the aqueous extracts of A. afra and C. roseus, and to use in silico methods to predict the potential of these phytochemicals to inhibit CYP2B6, the enzyme that metabolises artemether. Analysis of the aqueous extracts using UHPLC-QTOF-MS identified a diverse array of phytochemicals in both plants. Potential CYP2B6 inhibitors were identified by docking the phytochemicals into the enzyme’s active site using Discovery Studio software. This in silico method was validated against three metrics: root mean square deviation, enrichment factor, and receiver operating characteristic. Three docking algorithms (LibDock, LigandFit, and CDOCKER) with native scoring functions and ten additional scoring functions were assessed. The LibDock/Ludi 3 combination most effectively distinguished active inhibitors. Multiple compounds, including acacetin, isoscopoletin, and scopoletin, found in A. afra demonstrated strong binding affinities to the active site of CYP2B6, suggesting that phytochemicals from A. afra could inhibit CYP2B6-mediated metabolism, potentially affecting the pharmacokinetic profiles of co-administered substrate drugs. Such inhibition could lead to increased drug plasma concentrations, increased levels of toxicity, or reduced therapeutic efficacy, underscoring a clinically relevant risk for herb-drug interactions in populations using these herbal remedies. HIGHLIGHTS • Prominent phytochemicals in extracts of Artemisia afra and Catharanthus roseus identified by UHPLC-QTOF-MS. • A structure-based in silico method was validated and used for molecular docking of phytochemicals identified. • Artemisia afra and Catharanthus roseus are rich in bioactive compounds; however, only A. afra phytochemicals successfully interacted with the target ligand, CYP2B6
Non-targeted metabolomics by 1H nuclear magnetic resonance spectroscopy; an interspecies comparison of milk between dromedary, giraffe and white rhinoceros with observations on blesbok
Osthoff, G.; Schmidt, L.; Tordiffe, Adrian Stephen Wolferstan; Deacon, F. (Elsevier, 2025-09)
Various researchers have shown that milk metabolomes differ between domestic species regarding metabolite composition as well as metabolic pathways of milk synthesis. We contribute to this knowledge by presenting data of wild mammals. Inter-species differences were noted; 3-fucosyllactose was only detected in the milk of dromedary, and N-phenylacetylglycine and UDP-N-acetylglucosamine only in giraffe. Hippurate and 2-oxaloacetate were absent from milk of dromedary; creatinine and glutamate from giraffe; nicotinamide from white rhinoceros; and dimethylamine, creatine, valine, acetone, fumarate and 2-oxaloacetate from blesbok. With MetaboAnalyst 6.0, 15 statistically important metabolites of dromedary, giraffe and white rhinoceros were identified for KEGG metabolic pathway enrichment. Twelve metabolic pathways were identified as important with a specialization within species. In the giraffe mammary cells, the amino sugar and nucleotide sugar metabolism was observed as active and the alanine, aspartate and glutamate metabolism as inactive. The glycerophospholipid metabolism seemed highly active in the white rhinoceros and the galactose metabolism active in both the dromedary and white rhinoceros. Milk was available from only two blesbok, but data is presented as observation.
Does cooling affect skeletal muscle glycogen replenishment after an acute bout of fear-induced exertional hyperthermia in blesbok (Damaliscus pygargus phillipsi)?
Kohn, Tertius Abraham; Martin, Mahmooda; Van Boom, Kathryn Merle; Donaldson, Byron; Blackhurst, Dee M.; Fitte, Agustina; Burroughs, Richard; Steyl, Johan Christian Abraham; Goddard, Amelia; Meyer, Leith Carl Rodney (Elsevier, 2025-11)
Rhabdomyolyses is a clinical sign of capture myopathy in wild animals and may be linked to glycogen metabolism. To study potential mechanisms, 26 wild blesbok were chased for 15 min and immobilised, whereafter 12 of these blesbok were doused with ice-water (n = 14 chased only group; n = 12 chased + cooled group). An additional 12 blesbok served as resting (not chased) uncooled controls. Vastus lateralis biopsies were obtained after immobilisation for biochemical analyses. Biopsies obtained at initial capture, 3- and 16-days post exercise were analysed for glycogen content. Blesbok muscles contained predominantly myosin heavy chain (MHC) IIA (∼50 ± 9 %), followed by IIX (32 ± 10 %) and MHC I (18 ± 5 %), with no difference between groups. Citrate synthase (mean: 87 ± 48), 3-hydroxyacetyl co A dehydrogenase (47 ± 17), lactate dehydrogenase (1567 ± 654), phosphorylase (162 ± 94), phosphofructokinase (250 ± 123) and creatine kinase (12,455 ± 6372) activities (in μmol/min/g prot) were not different between groups. Similarly, superoxide dismutase (7.9 ± 7 U/mg prot), catalase (8.8 ± 5.8 mmol/min/g prot), and overall antioxidant capacity (ORAC: 23055 ± 18,460 μmol/g prot) were not different between groups. Glycogen content was reduced in both chased groups and not replenished by day 3. Glycogen supercompensation was observed on day 16 in both chased groups (∼33 % higher than resting control group). The results confirm that blesbok have high muscle metabolic capacities, and that glycogen resynthesis is slow, which could lead to metabolite deficiency during prolonged chase events (>15 min).
Building the future One Health workforce in Eastern and Southern Africa : gaps and opportunities
Wako, Buke Yussuf; Richards, Shauna; Grace , Delia; Mutie, Ianetta; Caron, Alex; De Nys, Helene; Goregena , Brighton; Kgosimore , Moatlhodi; Kimaro, Esther; Qekwana, Daniel Nenene; Tadesse, Yordanos; Knight-Jones, Theo; Mutua, Florence (CAB International, 2025-04-10)
The Quadripartite comprised of the Food and Agriculture Organization (FAO), World Health Organization (WHO), World Organisation for Animal Health (WOAH), the United Nations Environment Program (UNEP), and the One Health High Level Expert Panel collectively support enhancing the One Health (OH) capacities of the workforce addressing OH issues; however, competencies for this workforce are not generally agreed upon, applied uniformly, or always relevant in the global South. The objectives of this study were to (1) develop an inventory of OH education offered by higher education institutes in Eastern and Southern Africa, and (2) define OH competencies relevant for OH training in Eastern and Southern Africa. A survey in 11 Eastern and Southern African countries was conducted with OH key informants purposively selected from higher education institutes offering OH education (n = 1–3/higher education institutes). Snowball sampling was used to identify additional higher education institutes/individuals. Results were validated by OH country representatives. Data were collected using questionnaires, and descriptive statistics were used to present the results. Forty-two questionnaires were completed from 29 higher education institutes, and 166 OH education interventions were reported with 69% being courses contributing to a degree, 21% as degree/diploma awarding, and the remainder were missing data (n = 16). Masters were the most common OH degree program of which the highest number of students taught were from public health/OH, food safety, and applied epidemiology. There are many OH educational courses and activities on offer in Eastern and Southern Africa; however, their total breadth is difficult to assess due to limited awareness of the availability of OH education not only between higher education institutes in a country but also even within a higher education institute between faculties. Numerous cross-cutting and technical competencies were considered essential to work in OH; however, this level of expertise is rarely logistically possible to provide in any single degree program. For OH education to be consistently applied, competency frameworks that are relevant to a region are necessary. Technical competencies are important from a disciplinary context; however, necessary cross-cutting competencies should be a focus in developing the future OH workforce.
Etorphine induces pathophysiology in immobilized white rhinoceros through sympathomimesis that is attenuated by butorphanol
Boesch, Jordyn M.; Gleed, Robin D.; Buss, Peter Erik; Tordiffe, Adrian Stephen Wolferstan; Zeiler, Gareth Edward; Miller, Michele A.; Viljoen, Francois; Harvey, Brian H.; Parry, Stephen A.; Meyer, Leith Carl Rodney (Oxford University Press, 2025-04)
Please read abstract in the article. LAY SUMMARY White rhinoceros are a sentinel species for ecosystems in southern Africa. Their conservation is dependent on occasional immobilization with the ultra-potent opioid etorphine. Unfortunately, etorphine produces sympathetic nervous system upregulation and severe physiological perturbations that may cause morbidity and mortality. Attenuating its effects contributes to white rhinoceros conservation.
Co-production and conservation physiology : outcomes, challenges and opportunities arising from reflections on diverse co-produced projects
Cooke, Steven J.; Bett, Nolan N.; Hinch, Scott G.; Adolph, Chief Bonnie; Hasler, Caleb T.; Howell, Bradley E.; Schoen, Alexandra N.; Mullen, Eric J.; Fangue, Nann A.; Todgham, Anne E.; Cheung, Melanie J.; Johnson, Rachel C.; Olstad, Rebekah Sze-Tung; Sisk, Marine; Sisk, Chief Caleen; Franklin, Craig E.; Irwin, Robert C.; Irwin, Terri R.; Lewandrowski, Wolfgang; Tudor, Emily P.; Ajduk, Hayden; Tomlinson, Sean; Stevens, Jason C.; Wilcox, Alana A.E.; Giacinti, Jolene A.; Provencher, Jennifer F.; Dupuis-Smith, Reyd; Dwyer-Samuel, Frederic; Saunders, Michelle; Meyer, Leith Carl Rodney; Buss, Peter Erik; Rummer, Jodie L.; Bard, Brittany; Fuller, Andrea (Oxford University Press, 2025-07)
As a relatively nascent discipline, conservation physiology has struggled to deliver science that is relevant to decision-makers or directly useful to practitioners. A growing body of literature has revealed that co-produced research is more likely to generate knowledge that is not only relevant, but that is also embraced and actionable. Co-production broadly involves conducting research collaboratively, inclusively, and in a respectful and engaged manner—spanning all stages from identifying research needs to study design, data collection, interpretation and application. This approach aims to create actionable science and deliver meaningful benefits to all partners involved. Knowledge can be co-produced with practitioners/managers working for regulators or stewardship bodies, Indigenous communities and governments, industry (e.g. fishers, foresters, farmers) and other relevant actors. Using diverse case studies spanning issues, taxa and regions from around the globe, we explore examples of co-produced research related to conservation physiology. In doing so, we highlight benefits and challenges while also identifying lessons for others considering such an approach. Although co-production cannot guarantee the ultimate success of a project, for applied research (such as what conservation physiology purports to deliver), embracing co-production is increasingly regarded as the single-most important approach for generating actionable science to inform conservation. In that sense, the conservation physiology community would be more impactful and relevant if it became commonplace to embrace co-production as demonstrated by the case studies presented here. LAY SUMMARY This article aims to highlight successful applications of co-production within the realm of conservation physiology. Relying on the diverse experiences of co-authors, we also offer guidance to those embracing co-production in their conservation physiology projects.

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