Research Articles (University of Pretoria)

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Patterns of mature woody plant species encroachment on vegetation structure, density, and diversity of the understory layer across the Marikana Thornveld
(Frontiers Media, 2025-05) Mangwane, Mziwanda; Madakadze, Ignacio Casper; Tjelele, Tlou Julius; Ramoelo, Abel; u14387027@tuks.co.za
INTRODUCTION : Bush encroachment has a negative impact on the vegetation structure, ecosystem functions, and services of savanna rangelands. Woody plant encroachment creates an imbalance in the grass-to-tree ratio, leading to a decline in ecosystem services, including grazing capacity and soil nutrients. METHODS : This study aimed to evaluate the vegetation structure, diversity, and relationships of tree species across four different growth stages in the Marikana Thornveld. Three sites were identified at the Roodelpaat experimental farm, where six 1-hectare plots were established. In each plot, nine 10 m × 10 m subplots were set up to identify mature woody plants, shrubs, and saplings. Seedlings were identified within three 1.69 m² quadrats nested within each subplot. RESULTS AND DISCUSSION : The study identified a total of 9,028 individual woody plants, including 158 seedling species, 161 saplings, 159 shrubs, and 154 mature woody plant species. The regression line plotted seedling density against the densities of mature trees, shrubs, and saplings, with b values significantly less than 1, indicating a negative impact of mature trees, shrubs, and saplings on the seedling layer. Seedling abundance displayed a non-linear relationship with mature trees, indicating a 4.75% representation of seedling abundance within the mature tree layer. Woody seedling species exhibited the highest abundance across four growth stages. Overall, across all woody plant species at different growth stages, there was a general decline in the woody density class, resulting in a J-shaped curve pattern. Seedlings and mature trees exhibited the highest diameter at breast height (dbh) proportions among individual woody plants from the first to the third DBH size classes, followed by a decline. CONCLUSION : Generally, these results highlight a weak relationship between mature woody plant species and the understory layer, including shrubs, saplings, and seedlings. Consequently, mature woody plants cannot predict the establishment of understory woody plants or the recruitment of seedlings as a cause of bush encroachment.
The development of a CBT-informed approach to supporting type 2 diabetes self-management
(Frontiers Media, 2025-02) Visagie, Elne; Deacon, Elmari; Kok, Rumando; elne.visagie@up.ac.za
BACKGROUND : The self-management of adults with type 2 diabetes proves to be a continuous challenge. Within the South African context, socio-economic disparities, unequal access to healthcare and varying healthcare beliefs augment these challenges. CBT is a time-sensitive and structured intervention that has been effectively implemented for chronic diseases. CBT has been employed to improve psychological outcomes in adults with type 2 diabetes, but there is limited research on how this therapeutic intervention can enhance self-management outcomes of type 2 diabetes. Adaptable CBT-based interventions are needed to promote a holistic approach to type 2 diabetes self-management and empower a broader range of healthcare professionals to provide targeted interventions. Flexible interventions can promote patient engagement and be integrated into various healthcare settings where patients already access services. METHOD : The study employed document analysis to develop CBT-informed guidelines. Data was analysed by means of content analysis. Two research studies formed the dataset, and categories and subcategories were identified. The categories were integrated and used to develop the CBT-informed guidelines. RESULTS : These guidelines were based on core CBT components and divided into the introduction, working, and consolidation phases. The guidelines specified the roles of healthcare practitioners who would implement them and provided skills and techniques for healthcare professionals and patients within each phase. CONCLUSION : The CBT-based interventions aimed to provide a tool for healthcare practitioners and patients in terms of flexibility, accessibility, and personalisation.
Simulation of the African ITCZ during austral summer seasons and ENSO phases : application of an RCM derived from stretched grid ESM
(Frontiers Media, 2025-07) Ramotubei, Teke Solomon; Landman, Willem Adolf; Mateyisi, Mohau J.; Nangombe, Shingirai S.; Beraki, Asmerom Fissehatsion
INTRODUCTION : Climate predictability across timescales in a changing climate presents a unique opportunity and challenges for state-of-the-art climate models. The use of regional climate models (RCMs) forced with interactively coupled Earth System Models (ESMs) for the sub-seasonal, seasonal, and decadal predictions is an actively growing research area. METHODS : The study explores a stretched-grid RCM constrained with an ESM which integrates a climate change signature. Spectral relaxation paradigm is applied to limit the climate drift within the range of the multi-model sea-surface temperature (SST) and sea-ice concentration (SIC) variability. The model retroactive ensemble simulations for November initialization are evaluated on the seasonal migration of the ITCZ during El-Niño and La-Niña phases, exploring both the spatial and zonal positions. The model is also evaluated on the ITCZ process’ characteristics that include the Hadley cell (HC), stream function and the subtropical jet stream (STJ) using quantitative methods. RESULTS : The RCM and the driving ESM demonstrate skillful performance in identifying the seasonal trajectory of both the spatial and zonal migration of the ITCZ during El-Niño and La-Niña. Moreover, the RCM also demonstrates a good skill in determining both the descending edge of the HC and the STJ with the highest mean percentage error of 16.3 and 7.5% for the HC and STJ latitudes, respectively. CONCLUSIONS : The November initialization of the RCM skillfully simulates the seasonal migration of the ITCZ (and related characteristics) aligned to the observations and reanalysis datasets. Notwithstanding, the RCM manifests a tendency of more dynamic error growth relative to its driving ESM as the lead time increases. Furthermore, the RCM is also out of phase with a southerly shift of the stream function compared to the 500 hPa reanalysis stream function. The modeling framework offers process oriented and teleconnection studies. It also provides great potential for climate applications with suitable bias corrections techniques, albeit the source and mechanism of its dynamic error growth deserve further investigation.
Research progress on climate change adaptation strategies to control invasive crop pest in sub-Saharan Africa : a bibliometric and systematic review
(Frontiers Media, 2025-02) Assede, Emeline Sessi Pelagie; Othoo, Calvince Ouko; Ly, Ahmadou; Bayisa, Gobena; Tarkegn, Temesgen Gashaw; Zohoun, Megnisse; N'goran, Anje-Jokebed
This bibliometric and systematic review assesses research progress and climate change adaptation strategies to control invasive crop pests in sub-Saharan Africa. Scientific publications on crop pest management in sub-Saharan Africa in a context of climate change adaptation were extracted from papers published between 1991 and 2024. A literature search was conducted on Scopus, dimension, and google scholar, followed by screening and data extraction in compliance with ROSES standards. Findings indicated that pests such as armyworms, fruit flies and coffee berry borer cause huge losses. Communities are adopting integrated pest management, water harvesting, drip irrigation, resistant varieties, and improving production efficiency. Agro-ecological practices reduce pest invasions while preserving the environment. Meanwhile, chemical insecticide use remains an emergency solution as its effects on pest control would be more efficient. However, promising approaches emerge around biocontrol, agroforestry integrating pest management, and gender-tailored strategies. Nevertheless, regional disparities persist in scientific output. In conclusion, while invasive pests represent a major plant health crisis in sub-Saharan Africa, this review highlights innovative adaptation strategies. Their development will require coordinated mobilization to catalyze the sustainable agro-ecological transition that sub-Saharan Africa needs to address these multidimensional challenges. Future research should assess farmer’s perception on the effectiveness of the existing pest management practices for invasive crop pests.
Multisystemic resilience and its impact on youth mental health : reflections on co-designing a multi-disciplinary, participatory study
(Frontiers Media, 2025-03) Theron, Linda C.; Bergamini, Matteo; Chambers, Cassey; Choi, Karmel; Fawole, Olufunmilayo I.; Fyneface, Fyneface Dumnamene; Höltge, Jan; Kapwata, Thandi; Levine, Diane T.; Mai Bornu, Zainab; Makape, Makananelo; Matross, Celeste; McGrath, Brian; Olaniyan, Olanrewaju; Stekel, Dov J.; Hey, Josh Vande; Wright, Caradee Yael; Zion, Ameh Abba; Ungar, Michael; linda.theron@up.ac.za
Youth depression is a global emergency. Redressing this emergency requires a sophisticated understanding of the multisystemic risks and biopsychosocial, economic, and environmental resources associated with young people's experiences of no/limited versus severe depression. Too often, however, personal risks and a focus on individual-level protective resources dominate accounts of young people's trajectories towards depression. Further, studies of depression in high-income countries (i.e., “western”) typically inform these accounts. This article corrects these oversights. It reports on the methodology of the Wellcome-funded R-NEET study: a multidisciplinary, multisystemic, mixed method longitudinal study of resilience among African youth whose status as “not in education, employment or training” (NEET) makes them disproportionately vulnerable to depression. Co-designed by academics, community-based service providers and youth in South Africa and Nigeria, with partnerships in the United Kingdom, Canada and the United States, the R-NEET study is identifying the physiological, psychological, social, economic, institutional, and environmental risks and resources associated with distinct trajectories of depression. Using the methodology of the R-NEET study as exemplar, this article advances an argument for understanding resilience as a contextually and culturally rooted capacity that draws on the multiple, co-occurring systems that young people depend upon to support their wellbeing. Acknowledging and harnessing the multiple systems implicated in resilience is critical to researchers and mental health providers who seek to support young people to thrive, and to young people themselves when protecting or promoting their mental wellbeing.
Characterization and risk stratification of coronary artery disease in people living with HIV : a global systematic review
(Frontiers Media, 2025-08) Nweke, Martins C.; Ibeneme, Sam; Pillay, Julian D.; Mshunqane, Nombeko
BACKGROUND : Coronary artery disease (CAD) is a leading cause of mortality among people living with HIV (PLWH). Risk stratification remains inconsistent due to geographic disparities, ART-related metabolic effects, and overreliance on strength of association. This review synthesizes global evidence to classify CAD risk factors in PLWH, aiming to improve predictive models and preventative strategies. METHODS : Following the PRISMA 2020 guidelines, a systematic review was conducted across six databases: PubMed, Scopus, Web of Science, Medline, CINAHL, and African Journals (SABINET). Two independent reviewers screened studies and extracted data. Narrative synthesis and meta-analysis were conducted. Risk factors were classified using Rw, causality index (CI), and public health priority (PHP). FINDINGS : Twenty-two studies involving 103,370 participants were included. First-class risk factors (CI: 7–10) included hypertension (OR: 4.9; p < 0.05; Rw: 4.5), advanced age (≥50 years) (OR: 4.96, p < 0.05, Rw: 3.58), dyslipidemia (OR: 2.15, p < 0.04, Rw: 2.15), and overweight/obesity (OR: 1.81, p < 0.05, Rw: 1.36). Second-class risk factors (CI: 5–6) included family history of CVD (OR: 3.25, p < 0.05; Rw: 2. 24). Third-class risk factors (CI ≤4) included diabetes (OR: 2.64, p < 0.05, Rw: 1.32), antiretroviral therapy exposure (OR: 1.68, p < 0.05, Rw: 0.63), and homosexuality (OR: 1.82, p < 0.05, Rw: 0.62). Critical thresholds (cumulative Rw: 14.8 and 8.0) were set at 75th and 50th percentiles of cumulative Rw. At GTT value of 0.50, the parsimonious global clinical prediction model for HIV-related CAD included age, hypertension, dyslipidemia, family history of CVD, diabetes, and overweight/obesity (Rw: 15.5, GTT: 4.05). For primary prevention, the optimal model comprised hypertension, dyslipidemia, and obesity (Rw: 8.01, GTT: 2.07). Advanced age and hypertension were “necessary causes” of CAD among PLWH. CONCLUSION : Association strength alone cannot determine CAD risk. Cumulative risk indexing and responsiveness provide a robust framework. Prevention should prioritize hypertension and dyslipidemia management, with interventions for obesity, smoking, and virological failure. Age and hypertension should prompt cardiovascular screening. Standardized risk definitions, accounting for the role of protective factors and integrating evidence with domain knowledge are vital for improved CAD risk stratification and prediction in PLWH. Routine cardiovascular screening in HIV care remains essential.
Forecasting South African grain prices and assessing the non-linear impact of inflation and rainfall using a dynamic Bayesian generalized additive model
(Frontiers Media, 2025-07) Antwi, Albert; Kammies, Emelia Thembile; Chaka, Lyson; Arasomwan, Martins Akugbe
INTRODUCTION : Accurate price forecasts and the evaluation of some of the factors that affect the prices of grains are crucial for proper planning and food security. Various methods have been designed to model and forecast grain prices and other time-stamped data. However, due to some inherent limitations, some of these models do not produce accurate forecasts or are not easily interpretable. Although dynamic Bayesian generalized additive models (GAMs) offer potential to overcome some of these problems, they do not explicitly model local trends. This may lead to biased fixed effects estimates and forecasts, thus highlighting a significant gap in literature. METHODS : To address this, we propose the use of random intercepts to capture localized trends within the dynamic Bayesian GAM framework to forecast South African wheat and maize prices. Furthermore, we examine the complex underlying relationships of the prices with inflation and rainfall. RESULTS : Evidence from the study suggests that the proposed method is able to adequately capture the dynamic localized trends consistent with the underlying local trends in the prices. It was observed that the estimated localized variations are significant, which led to improved and efficient fixed-effect parameter estimates. This led to better posterior predictions and forecasts. A comparison to the static trend Bayesian GAMs and the autoregressive integrated moving average (ARMA) models indicates a general superiority of the proposed approach for the posterior predictions and long-term posterior forecasts and has potential for short-term forecasts. The static trend Bayesian GAMs were found to generally outperform the ARMA models in long-term posterior forecasts and also have potential for short-term forecasts. However, for 1-step ahead posterior forecasts, the ARMA models consistently outperformed all the Bayesian models. The study also unveiled a significant direct nonlinear impact of inflation on wheat and maize prices. Although the impacts of rainfall on wheat and maize prices are indirect and nonlinear, only the impact on maize prices is significant. DISCUSSION : The improved efficiency and forecasts of our proposed method suggest that researchers and practitioners may consider the approach when modelling and forecasting long-term prices of grains, other agricultural commodities, speculative assets and general single-subject time series data exhibiting non-stationarity.
A new mathematical model for water uptake during soaking of grains
(World Scientific Publishing, 2025-06) Rostamirad, Sholeh; Duodu, Kwaku Gyebi; Meyer, Josua P.; Sharifpur, Mohsen; gyebi.duodu@up.ac.za
There are very few models in the open literature for predicting the water uptake characteristics of grains. Peleg’s equation (1988) is a widely used empirical model that does not involve important soaking parameters to describe water uptake. Other existing models have been developed based on the diffusion theory. However, these existing models are strongly connected to experimental data for predicting the equilibrium moisture of the grain (maximum water uptake with time). In practice, the soaking of grain involves many physical parameters such as time, temperature, the viscosity of the soaking medium, the density of grain and soaking medium, diffusion coefficient, and solid loss from the grain (for example alpha-galactosides). However, there is no documentation of a model involving these physical parameters. This present work proposed a generalized mathematical model for predicting water uptake of grain (cowpeas) using non-dimensional analysis. The proposed model was successively applied to predict the soaking of cowpeas via the simplification of the model using six data points from experimental works in the literature. In predicting the soaking characteristics of different cowpeas, a good agreement was observed when the proposed model was compared with existing experimental data in the literature. This work presents a novel way of predicting water uptake in cowpeas using non-dimensional analysis which can be applied by food scientists and food engineers to model the water uptake for other grains. However, the physics of soaking, particularly as the porous structure of the grain evolves, could be analyzed using fractal mathematics. This approach should be considered for future studies to capture the complex, irregular dynamics of the process more accurately.
Cryphonectria Canker on Eucalyptus in Florida reconsidered
(Wiley, 2025-08) Pham, Nam Q.; Wingfield, Brenda D.; Marincowitz, Seonju; Brawner, Jeremy T.; Hulcr, Jiri; Wingfield, Michael J.; nam.pham@fabi.up.ac.za
Cryphonectria canker is one of the most important diseases of plantation-grown Eucalyptus spp. in the tropics and Southern Hemisphere. The disease has been known in Florida, USA, for many years, and the causal agents are attributed to two known canker pathogens, Chrysoporthe cubensis (≡ Cryphonectria cubensis) and Microthia havanensis (≡ Endothia havanensis). These identifications were based on morphological characteristics, which are inadequate to recognise cryptic species in the Cryphonectriaceae. In this study, we visited various sites in Florida where Eucalyptus grandis and E. amplifolia trees are cultivated and investigated the presence of cankers. Isolations were made from fungal structures on symptomatic tissues associated with cankers. A total of 41 cultures resembling Cryphonectriaceae spp. were isolated. The isolates were identified based on DNA sequences for the ITS region of the rRNA and sections of the β-tubulin gene, and confirmed as the three species of Cryphonectriaceae, namely Microthia havanensis, Chrysoporthe cubensis and Chrysoporthe doradensis. Of these, Chrysoporthe doradensis was discovered for the first time in the USA. In addition, this study represents the first record of any Cryphonectriaceae on E. amplifolia , a Eucalyptus species that is poorly studied in terms of disease. Pathogenicity trials on Eucalyptus showed that all three Cryphonectriaceae species could cause disease on these trees, with Chrysoporthe spp. being more aggressive. These findings highlight the importance of continuous monitoring and surveillance to detect emerging pathogens and safeguard the sustainability of Eucalyptus in non-native forestry systems.
Next generation sequencing : a possible answer to sudden unexplained deaths in a young South African cohort?
(Springer, 2025-09) Van Deventer, Barbara Stroh; Du Toit-Prinsloo, Lorraine; Van Niekerk, Chantal; u26376645@tuks.co.za
Sudden cardiac death (SCD) is a major public health concern. In sub-Saharan Africa (SSA), including South Africa, there is a lack of reliable statistics on the incidence of SCD, even though there has been a fourfold increase in noncommunicable diseases (NCD), particularly cardiovascular diseases (CVD). Sudden cardiac death contributes to an estimated 50% of all cardiovascular deaths, which highlights South Africa’s need for research into better detection, treatment and prevention. This study aimed to identify an inherited cardiac arrhythmogenic disorder, linked to variants in cardiomyopathy- and arrhythmia-related genes, as a potential contributing factor to sudden cardiac deaths. DNA was extracted from blood samples collected at autopsy of 51 sudden unexpected death (SUD) cases, and subjected to next-generation sequencing (NGS) of 49 genes linked to inherited cardiac arrhythmogenic disorders. Variants were annotated and interpretated for clinical significance using the Galaxy bioinformatic platform. In total, 175 different missense variants were identified in the study population (n = 51). Of these, 92.5% (162/175) were known, documented variants, and the remaining 7.4% (13/175) were considered novel. Of the known variants, 78.4% (127/162) were of benign/likely benign significance, 20.4% (33/162) were variants of unknown significance (VUS), and 1.2% (2/162) was pathogenic. The 13 novel variants were analysed using online prediction software, with 92.3% (12/13) predicted to be likely benign and 7.7% (1/13) grouped into the VUS category. Post-mortem genetic testing provided evidence of a genetic arrhythmic/cardiac conduction disorder as the probable pathogenic basis for approximately 4% (2/51) of sudden unexpected death (SUD) cases.
Insect succession patterns on pig carrion in southern Nigeria
(Springer, 2025-06) Etoniru, Izuchukwu Stanley; Brits, Desire; Myburgh, Jolandie; Steyn, Maryna; Hill, Lawrence
In analyzing decomposing human remains in cases of unattended death, observing insect succession patterns to aid in estimating the post-mortem interval (PMI) based on carrion insects is one of the tasks of the forensic entomologist. The purpose of this study is to provide baseline data in order to improve PMI estimates using carrion insects. The lingering armed conflict in Nigeria creates a situation where unidentified human remains overwhelm law enforcement agencies. A common challenge is the lack of affordable, easy-to-use, and locally derived methods. This study aims to describe the succession patterns of arthropods, including insects, in pig carcasses in the wet and dry seasons in southern Nigeria as a baseline to aid in PMI estimation. Arthropods were observed and collected (all life cycle stages) in a total of 20 freshly-killed pigs (10 pigs for each season) which were deployed to study sites within 3 h of humane killing and at various times during the two seasons over 14 months. The time of appearance, activity, and disappearance of the arthropods were noted and related to the stages of decomposition to create succession patterns. Three classes, six orders, and 16 families of arthropods were collected. Musca domestica was the first to arrive, followed by Chrysomya marginalis, visiting within 10 min after placement. An ant species (Family Formicidae) had the widest presence through decomposition stages. There was an increase in the absolute number and species richness of arthropods in the wet season. Some arthropods, like the black soldier fly (Hermetia illucens), were exclusively present in the wet season. The observed succession patterns can be used as a reference for forensic scientists to aid in PMI assessment in Nigeria. Arthropods found exclusively in a season could be used to establish the season of death.
Biovaluation of Cucurbitaceae fruit byproducts as potential ruminant meat tenderizers : a scoping review and process conceptual framework
(Elsevier, 2025-10) Mashele, Grace; Semwogerere, Farouk; Mushi, Daniel; Kayitesi, Eugenie; Chimphango, Annie; Mapiye, Cletos
Current tropical ruminant production systems, which are based on natural pasture, indigenous breeds and marketing of older animals produce less tender meat with limited economic value and low consumer acceptance. While plant cysteine proteases offer natural and potentially safer alternatives to chemical and mechanical meat tenderizers, challenges remain, particularly enzyme stability and over-tenderization. Interestingly, serine proteases derived from byproducts of the Cucurbitaceae family, one of the most widespread, abundant and genetically diverse indigenous fruit plants in the tropics exhibit significant stability and substrate specificity suggesting greater potential for application in meat tenderization but remain underexploited. The current review explored the potential of serine proteases containing extracts derived from tropical Cucurbitaceae fruits byproducts (CFB) as meat tenderizers and customized a process conceptual framework for their biovaluation. Many in vitro studies indicated that CFB-derived serine proteases have wider substrate specificity and greater stability over a broad range of pH, thermal and oxidative environments. Evidence from the few available in producto studies on cucumisin-like serine proteases derived from Cucumis trigonus species in the Cucurbitaceae family suggests that they may possess collagenolytic activity and meat texture enhancing properties comparable to those of cysteine proteases. A transdisciplinary research approach was recommended to further explore purification, efficacy, underlying mechanisms of action, application conditions, safety and cost-effectiveness of novel CFB-based serine proteases as meat tenderizers. A process conceptual framework was customized to guide the biovaluation research of CFBs and promote innovative utilization and entrepreneurship along ruminant meat value chains. HIGHLIGHTS • Cucurbit serine proteases (CSPs) exhibit higher stability than cysteine proteases. • CSPs seem to display comparable collagenolytic activity to cysteine proteases. • Cucurbit fruit byproducts (CFB) have meat preservative and flavoring properties. • CFB-extracts appear to have potential as meat tenderizers and quality enhancers.
Infection rates of Fasciola spp. in cattle slaughtered at 13 abattoirs in six of nine provinces of South Africa
(Elsevier, 2025-06) Nukeri, Sophy; Malatji, Mokgadi Pulane; Sithole, Msawenkosi I.; Ngcamphalala, Philile I.; Nyagura, Ignore; Tembe, Danisile; Ndlovu, Innocent Siyanda; Chaisi, Mamohale E.; Mukaratirwa, Samson
Fasciolosis or liver fluke infection is a snail-borne disease that affects the productivity of domestic ruminants including liver condemnation especially in cattle. However, there is paucity of information on the burden of infection due to lack of accurate data on liver condemnation related to correct geographical origin of infected animals. This distorts perception of the geographical occurrence of fasciolosis, particularly in South Africa among other countries. We aimed to determine the infection rates of Fasciola spp. in cattle slaughtered at selected abattoirs in South Africa. A total of 13 abattoirs consisting of 10 high throughput and three low throughput abattoirs across six provinces, were visited to screen for liver fluke infection in slaughtered cattle including tracing of the animals' geographical origin. A total of 57 livers from 673 slaughtered cattle (8.5 %) from 10 abattoirs were infected with Fasciola spp.. The highest infection rate from the study sites was 37 % and the lowest 4.5 %. Tracing of infected cattle showed that some abattoirs slaughtered cattle originating from other provinces. Forty-nine percent (29/57) of infected cattle had moderate body condition score (BCS) and recorded the highest intensity of fluke infection (>100 flukes per liver). Furthermore, young animals had high infection rates (51 %; 29/57) compared to adults (49 %; 28/57) and females (54 %; 31/57) compared to males (46 %; 26/57). The overall results highlighted the presence of Fasciola spp. in five provinces of South Africa, represented by more than four agro-ecological zones. Fasciola hepatica occurred in all six provinces while both Fasciola spp. co-occurred in one province. Furthermore, F. hepatica constituted the highest percentage (74 %; 710/960) of Fasciola spp. specimens collected. Fasciola gigantica were collected from abattoirs in one province and constituted 26 % (250/960) of the total collected flukes. Results from the study provide information on the burden of fasciolosis in cattle. This is based on abattoir surveys in South Africa, considering the traced geographical origin of animals slaughtered. Using data from surveys of this nature might support efforts to map the geographical distribution of fasciolosis in South Africa. Thus, contribute towards the development of effective control and treatment programs of fasciolosis to mitigate the burden of the disease in cattle. HIGHLIGHTS • Fasciolosis is prevalent in cattle slaughtered at abattoirs from six provinces of South Africa. • Cattle movement for slaughter distorts the true prevalence at provincial level. • Cattle movement may contribute to introduction of infections to new areas. • Fasciola hepatica was recorded in all six provinces. • Fasciola gigantica co-occurred with F. hepatica in the Limpopo province.
Amino acids, UPLC-MS phenolic metabolites and multivariate approach for elucidating the effect of two growing conditions on growth and yield attributes in okra pods and leaves
(Elsevier, 2025-03) Mokgalabone, Tyson T.; Mpai, Semakaleng; Nyakudya, Trevor Tapiwa; Ndhlala, Ashwell R.
Okra is one of the highly nutritious indigenised food crops in Southern Africa. The study intended to evaluate plant growth, yield, amino acids, and untargeted semi-targeted phenolic metabolites grown concurrently at greenhouse and micro-plot under open-field conditions. Yield and growth attributes: stem diameter, plant height, number of branches per plant, number of pods per plant, pod weight, pod length and pod diameter were higher in the micro-plot under open-field conditions. Sixteen amino acids were quantified and arginine, serine, glycine, aspartate, glutamate, alanine, proline, histidine, threonine, methionine, lysine, tyrosine, leucine, valine, and isoleucine were higher in leaf samples grown in micro-plots under open-field than greenhouse samples. UPLC-MS phenolic metabolites associated with the two growth conditions were quercetin 3-galactoside, succinyl adenosine, quercetin 3-lathyroside, isotan b and icariside F2b which were either highly upregulated or downregulated. Growth conditions can be used to manipulate the accumulation of free amino acids and phenolic metabolites. HIGHLIGHTS • Effect of growing conditions on plant growth, yield and chemical composition of okra. • Open field growing condition improved growth and yield attributes of okra. • Open field condition enhanced the accumulation of sixteen amino acid in the studied okra. • Phenolic acids and flavonoids were predominant in the studied okra samples. • Growth Conditions in okra affected presence of key metabolites.
Nutritional and functional properties of decorticated and microwave heat moisture treated white sorghum meal with added non-tannin and tannin phenolic extract
(Elsevier, 2025-05) Baah, Rose Otema; Duodu, Kwaku Gyebi; Harasym, Joanna; Emmambux, Mohammad Naushad; naushad.emmambux@up.ac.za
Emerging technologies, particularly microwave energy, have proven to be more efficient for heat moisture treatment to enhance starch functionality. In a sorghum food system, interactions between starch-phenolics and protein-phenolics significantly influence the nutritional properties of the food. Microwave heat moisture treatment decreased the starch hydrolysis index of sorghum meals from 69.89 % to 54.33 % in samples without phenolic extracts. The hydrolysis index was further reduced from 59.27 to 35.99 % and 54.74 to 36.18 % in samples containing non-tannin and tannin phenolic extracts. The addition of phenolics led to increased resistant starch content, characterized by higher levels of slowly digestible starch and a lower glycaemic index. The interactions between phenolic compounds, protein, starch, and the α-amylase enzyme contribute to the increased resistant starch content. Specifically, phenolics and proteins form barriers around starch granules that hinder digestion. Furthermore, interactions between phenolics and amylose further decrease digestibility while inhibiting α-amylase activity. HIGHLIGHTS • Microwave heat moisture treatment of sorghum meal slows down starch hydrolysis • Adding phenolic extracts further reduces starch digestibility • Phenolic addition and heat moisture treatment increases resistant starch
Techno-functional properties of protein-rich flours from different species of edible insects as affected by drying methods
(Elsevier, 2025-12) Yisa Njowe, Kieran Bong; Duodu, Kwaku Gyebi; Emmambux, Mohammad Naushad; naushad.emmambux@up.ac.za
Food-based ingredients from insects can circumvent the challenging disgust factor of consuming edible insects as food. The functional properties of dried edible insect flour could guide the use of edible insects as food ingredients in familiar foods. This study investigated the effect of freeze drying, oven drying, sun drying, solar cabinet drying, boiled before either sun drying or solar cabinet drying techniques on the functional properties of protein-rich flours from edible grasshoppers, crickets, and caterpillars. The Nitrogen solubility indices (NSI), water solubility indices (WSI) and β-sheets for all boiled solar-dried grasshopper, cricket, and caterpillar protein concentrates decreased compared to the other dried forms of grasshopper, cricket and caterpillars. The insect protein concentrates had lower foaming (32–49 %) and emulsion capacities (65–78 %) compared to commercial soy (FC: 55.9 %, EC: 94.3 %) and whey (FC: 52.9–55.6 % EC: 93.7–96.3 %) protein ingredients but exhibited higher foam stability (43.2–52.8 %) and good emulsion stability (83.4–93.0 %). Defatted insect flour could have proteins with intermediate molecular weight (≈100 kDa) that denature and aggregate at air-water interface to form thick viscous films that stabilise the foam. The high foaming and emulsion properties of these protein concentrates suggest they could be good ingredients in bread and sausages, respectively. HIGHLIGHTS • Functional properties of edible insect protein concentrate depend on the species. • Heat treatment before drying changes secondary structure of edible insect proteins. • Edible insect protein concentrates have potential applications in the food industry.
Comparative analysis of five African traditional multipurpose crops using a food systems approach
(Taylor and Francis, 2025) Munialo, Sussy; Madzorera, Isabel; Lartey, Anna; Abdallah Noor, Ramadhani; Thiam, Aboubacry; Covic, Namukolo; Amos, Laar; Adelheid, Onyango; Baye, Kaleab; Nikiema, Laetitia Ouedraogo; Wafaie, Fawzi; Sibanda, Lindiwe Majele; sussy.munialo@up.ac.za
Diversifying food systems with traditional multi-purpose crops like sorghum, cassava, and amaranth is key to improving food security and nutrition. However, studies focusing on a variety of nutrient-dense crops, addressing research, policy, and practice, are missing. Most research focuses on cereals like sorghum, overlooking other crops such as vegetables, root crops, legumes, and nuts, limiting nutrient diversity in food system. A review of five traditional crops—sorghum, amaranth, cassava, cowpea, and cashew nuts—assessed research, policy, and practice, aiming to enhance food systems. The review found that existing initiatives on traditional crops are mainly production-focused and region-specific, with gaps in processing, value addition, marketing, nutrition, consumption, and transport. Limited policies and stakeholder involvement has hindered commercialization. Key recommendations should be implemented across research, practice, and policy along the food systems. Research actions include improving taxonomic classification, developing modern breeding programs, researching yield gaps, and enhancing understanding of transport and logistics. Practical strategies involve improving field management through training, integrating informal and formal seed systems, and promoting commercial use. Policies should address all food system aspects including processing, consumption, marketing, and transportation. Increased stakeholder engagement across the value chain is essential for unlocking the potential of traditional crops.
Fungal Planet description sheets : 1697–1780
(Westerdijk Fungal Biodiversity Institute, 2024-12-06) Crous, Pedro W.; Wingfield, Michael J.; Jurjević, Ž.; Balashov, S.; Osieck, E.R.; Marin-Felix, Y.; Luangsa-ard, J.J.; Mejía, L.C.; Cappelli, A.; Parra, L.A.; Lucchini, G.; Chen, J.; Moreno, G.; Faraoni, M.; Zhao, R.L.; Weholt, Ø.; Borovička, J.; Jansen, G.M.; Shivas, R.G.; Tan, Y.P.; Akulov, A.; Alfenas, A.C.; Alfenas, R.F.; Altés, A.; Avchar, R.; Barreto, R.W.; Catcheside, D.E.A.; Chi, T.Y.; Esteve-Raventós, F.; Fryar, S.C.; Hanh, L.T.M.; Larsbrink, J.; Oberlies, N.H.; Olsson, L.; Pancorbo, F.; Raja, H.A.; Thanh, V.N.; Thuy, N.T.; Ajithkumar, K.; Akram, W.; Alvarado, P.; Angeletti, B.; Arumugam, E.; Atashi Khalilabad, A.; Bandini, D.; Baroni, T.J.; Barreto, G.G.; Boertmann, D.; Akram, W.; Alvarado, P.; Angeletti, B.; Arumugam, E.; Atashi Khalilabad, A.; Bandini, D.; Baroni, T.J.; Barreto, G.G.; Boertmann, D.; Bose, Tanay; Castañeda Ruiz, R.F.; Couceiro, A.; Cykowska-Marzencka, B.; Dai, Y.C.; Darmostuk, V.; Da Silva, S.B.G.; Dearnaley, J.D.W.; De Azevedo Santiago, A.L.C.M.; Declercq, B.; De Freitas G. , L.W.S.; De la Peña-Lastra, S.; Delgado, G.; De Lima, C.L.F.; Dhotre, D.; Dirks, A.C.; Eisvand, P.; Erhard, A.; Ferro, L.O.; García, D.; García-Martín, A.; Garrido-Benavent, I.; Gené, J.; Ghobad-Nejhad, M.; Gore, G.; Gunaseelan, S.; Gusmão, L.F.P.; Hammerbacher, Almuth; Hernández-Perez, A.T.; Hernández-Restrepo, M.; Hofmann, T.A.; Hubka, V.; Jiya, N.; Kaliyaperumal, M.; Keerthana, K.S.; Ketabchi, M.; Kezo , K.; Knoppersen, Rosa; Kolarczyková, D.; Kumar, T.K.A.; Læssøe, T.; Langer, E.; Larsson, E.; Lodge, D.J.; Lynch, M.J.; Maciá-Vicente, J.G.; Mahadevakumar, S.; Mateos, A.; Mehrabi-Koushki, M.; Miglio, B.V.; Noor, A.; Oliveira, J.A.; Pereira, O.L.; Piątek, M.; Pinto, A.; Ramírez, G.H.; Raphael, B.; Rawat, G.; Renuka, M.; Reschke, K.; Ruiz Mateo, A.; Saar, I.; Saba, M.; Safi, A.; Sánchez, R.M.; Sandoval-Denis, M.; Savitha, A.S.; Sharma, A.; Shelke, D.; Sonawane, H.; Souza, M.G.A.P.; Stryjak-Bogacka, M.; Thines, M.; Thomas, A.; Torres-Garcia, D.; Traba, J.M.; Vauras, J.; Vermaas, M.; Villarreal, M.; Vu, D.; Whiteside, E.J.; Zafari, D.; Starink-Willemse, M.; Groenewald, J.Z.; Akram
Novel species of fungi described in this study include those from various countries as follows: Antarctica, Leuconeurospora bharatiensis from accumulated snow sediment sample. Argentina, Pseudocercospora quetri on leaf spots of Luma apiculata. Australia, Polychaetomyces verrucosus on submerged decaying wood in sea water, Ustilaginoidea cookiorum on Scleria levis, Xylaria guardiae as endophyte from healthy leaves of Macaranga tanarius. Belgium, Iodophanus taxi on leaf of Taxus baccata. Belize, Hygrocybe mirabilis on soil. Brazil, Gongronella irregularis from soil, Linodochium splendidum on decaying sheath of Euterpe oleracea, Nothophysalospora agapanthi (incl. Nothophysalospora gen. nov.) on flower stalks of Agapanthus praecox, Phaeosphaeria tabebuiae on leaf of Tabebuia sp., Verrucohypha endophytica (incl. Verrucohypha gen. nov.) from healthy roots of Acrocomia aculeata. Estonia, Inosperma apricum on soil under Quercus robur. Greece, Monosporascus solitarius isolated from surface-sterilised, asymptomatic roots of Microthlaspi perfoliatum. India, Diaporthe neocapsici on young seedling stems of Capsicum annuum, Fuscoporia naditirana on dead wood, Sebacina spongicarpa on soil, Torula kanvae from the gut of a Copris signatus beetle. Iran, Sarcinomyces pruni from twig and petiole tissues of Prunus persica and Prunus armeniaca, Xenodidymella quercicola from leaf spots of Quercus brantii. Italy, Agaricus aereiceps on grass, Agaricus bellui in meadows, Agaricus fabrianensis in urban grasslands, Beaucarneamyces muscorum on moss growing in forest, Xenoanthostomella quercus on leaf litter of Quercus ilex. Netherlands, Alfaria neerlandica on stem lesions of Cortaderia selloana, Neodictyosporium juncicola on culms of Juncus maritimus, Penicillium geertdesnooi from soil under Papaver rhoeas, Russula abscondita on rich calcareous soil with Quercus, Russula multiseptata on rich clay soil with Quercus, Russula purpureopallescens on soil with Populus, Sarocladium caricicola on leaves of Carex riparia. Pakistan, Circinaria shimlaensis on limestone rocks. Panama, Acrocalymma philodendri on leaf spots of Philodendron sp., Caligospora panamaensis on leaf litter, Chlamydocillium simulans associated with a Xylaria sp., Corynesporina panamaensis on leaf litter, Cylindromonium panamaense on twig litter of angiosperm, Cyphellophora panamaensis on twig litter of angiosperm, Microcera panamensis on leaf litter of fern, Pseudotricholoma pusillum in tropical montane forest dominated by Quercus spp., Striaticonidium panamaense on leaf litter, Yunnanomyces panamaensis on leaf litter. Poland, Albocremella abscondita (incl. Albocremella gen. nov.) from rhizoids of liverwort Conocephalum salebrosum. Portugal, Agaricus occidualis in meadows. South Africa, Alternaria elsarustiae on culms of unidentified Poaceae, Capronia capensis on dead twig of unidentified angiosperm, Codinaeella bulbinicola on dead leaves of Bulbine frutescens, Cytospora carpobroticola on leaf of Carpobrotus quadrifidus, Neophaeomoniella watsoniae on leaf of Watsonia sp., Neoplatysporoides aloigena on leaf of Aloe khamiesensis, Nothodactylaria comitabilis on living leaf of Itea rhamnoides, Nothopenidiella beaucarneae (incl. Nothopenidiella gen. nov.) on dead leaves of Beaucarnea stricta, Orbilia kirstenboschensis on dead flower stalks of Agapanthus praecox, Phragmocephala agapanthi on dead flower stalks of Agapanthus praecox, Podocarpigena hagahagaensis (incl. Podocarpigena gen. nov.) on leaf spots of Podocarpus falcatus, Sporisorium enterogonipteri from the gut of Gonipterus sp., Synnemapestaloides searsiae on leaf of Searsia populifolia, Xenophragmocapnias diospyri (incl. Xenophragmocapnias gen. nov.) on leaf spots of Diospyros sp., Yunnanomyces hagahagaensis on leaf spots of Sideroxylon inerme. Spain, Agaricus basicinctus in meadows, Agaricus quercetorum among leaf litter in oak forests, Coprinopsis palaciosii on degraded woody debris, Inocybe complutensis in calcareous loamy soil, Inocybe tanitiae in calcareous sandy soil, Mycena subfragosa on dead leaves of Salix atrocinerea, Pseudobaeospora cortegadensis in laurel forests, Trichoderma sedimenticola from fluvial sediments. Sweden, Inocybe badjelanndana on calcareous soil. Ukraine, Beaucarneamyces lupini on overwintered stems of Lupinus polyphyllus, Protocreopsis globulosa on thallus and apothecia of Lecania cyrtella on bark of Populus sp., Thyridium tiliae on dead twigs of Tilia sp. USA, Cladosporium louisianense, Cyphellophora americana from a bedroom vent, Extremus massachusettsianus from lyse buffer, Myxotrichum tapetae on carpet in basement, Neospissiomyces floridanus (incl. Neospissiomyces gen. nov.) on swab from hospital, Polychaetomyces marinus (incl. Polychaetomyces gen. nov.) on submerged driftwood in sea water, Steccherinum fragrans on hardwood fallen on the beach, Steinbeckomyces carnegieae (incl. Steinbeckomyces gen. nov.) on Carnegiea gigantea, Tolypocladium pennsylvanicum from air sampled in basement. Vietnam, Acidomyces ducanhii from Aglaia flowers, Acidomyces paludis from dead bark of Acacia sp., Phakopsora sageretiae on Sageretia theezans, Puccinia stixis on Stixis scandens. Morphological and culture characteristics are supported by DNA barcodes
Trends and levels of the global, regional, and national burden of appendicitis between 1990 and 2021 : findings from the Global Burden of Disease Study 2021
(Elsevier, 2024-09) Han, Hannah; Letourneau, Ian D.; Abate, Yohannes Habtegiorgis; Abdelmasseh, Michael; Abu-Gharbieh, Eman; Adane, Tigist Demssew; Ahinkorah, Bright Opoku; Ahmad, Aqeel; Ahmadi, Ali; Ahmed, Ayman; Alhalaiqa, Fadwa Naji; Al-Sabah, Salman Khalifah; Al-Worafi, Yaser Mohammed; Amu, Hubert; Andrei, Catalina Liliana; noushiravani, Amir A.; Arabloo, Jalal; Aravkin, Aleksandr Y.; Ashraf, Tahira; Azadnajafabad, Sina; Baghcheghi, Nayereh; Bagherieh, Sara; Bantie, Berihun Bantie; Bardhan, Mainak; Basile, Guido; Bayleyegn, Nebiyou Simegnew; Behnoush, Amir Hossein; Bekele, Alehegn; Bhojaraja, Vijayalakshmi S.; Bijani, Ali; Biondi, Antonio; Burkart, Katrin; Chu, Dinh-Toi; Chukwu, Isaac Sunday; Cruz-Martins, Natalia; Dai, Xiaochen; Demessa, Berecha Hundessa; Dhali, Arkadeep; Diaz, Daniel; Do, Thanh Chi; Dodangeh, Milad; Dongarwar, Deepa; Dsouza, Haneil Larson; Ekholuenetale, Michael; Ekundayo, Temitope Cyrus; El Sayed, Iman; Elhadi, Muhammed; Fagbamigbe, Adeniyi Francis; Fakhradiyev, Ildar Ravisovich; Ferrara, Pietro; Fetensa, Getahun; Fischer, Florian; Gebrehiwot, Mesfin; Getachew, Melaku; Golechha, Mahaveer; Gupta, Vivek Kumar; Habib, Joseph R.; Hadi, Najah R.; Haep, Nils; Haile, Teklehaimanot Gereziher; Hamilton, Erin B.; Hasan, Ikramul; Hasani, Hamidreza; Hassanzadeh, Sara; Haubold, Johannes; Hay, Simon I.; Hayat, Khezar; Ilesanmi, Olayinka Stephen; Inamdar, Sumant; Iwu, Chidozie Declan; Iyasu, Assefa N.; Jayarajah, Umesh; Jayaram, Shubha; Jokar, Mohammad; Jomehzadeh, Nabi; Joseph, Abel; Joseph, Nitin; Joshua, Charity Ehimwenma; Kabir, Ali; Kandel, Himal; Kauppila, Joonas H.; Kemp Bohan, Phillip M.; Khajuria, Himanshu; Khan, Maseer; Khatatbeh, Haitham; Kim, Min Seo; Kisa, Adnan; Kompani, Farzad; Koohestani, Hamid Reza; Kumar, Rakesh; Le, Thao Thi Thu; Lee, Munjae; Lee, Seung Won; Li, Ming-Chieh; Lim, Stephen S.; Lo, Chun-Han; Lunevicius, Raimundas; Malhotra, Kashish; Maugeri, Andrea; Mediratta, Rishi P.; Meretoja, Tuomo J.; Mestrovic, Tomislav; Mirza-Aghazadeh-Attari, Mohammad; Mohamed, Nouh Saad; Mokdad, Ali H.; Monasta, Lorenzo; Moni, Mohammad Ali; Moradi, Maryam; Mougin, Vincent; Mukoro, George Duke; Murillo-Zamora, Efren; Murray, Christopher J.L.; Naimzada, Mukhammad David; Najmuldeen, Hastyar Hama Rashid; Natto, Zuhair S.; Negoi, Ionut; Nguyen, Hien Quang; Nikolouzakis, Taxiarchis Konstantinos; Olufadewa, Isaac Iyinoluwa; Padubidri, Jagadish Rao; Pandey, Ashok; Parikh, Romil R.; Pham, Hoang Tran; Pollok, Richard C.G.; Rahimi, Mehran; Rahimi-Movaghar, Vafa; Rahman, Mosiur; Rahmani, Shayan; Rashidi; Rawaf, Salman; Rickard, Jennifer; Rouientan, Hamidreza; Roy, Simanta; Saddik, Basema Ahmad; Saeed, Umar; Saleh, Mohamed A.; Salehi, Sana; Samy, Abdallah M.; Sanabria, Juan; Sankararaman, Senthilkumar; Schumacher, Austin E.; Senthilkumaran, Subramanian; Shah, Pritik A.; Shool, Sina; Sibhat, Migbar Mekonnen; Sidamo, Negussie Boti; Singh, Jasvinder A; Socea, Bogdan; Solomon, Yonatan; Sreeram, Saraswathy; Tabatabaei, Seyyed Mohammad; Tan, Ker-Kan; Tavangar, Seyed Mohammad; Tefera, Yibekal Manaye; Thomas, Nikhil Kenny; Ticoalu, Jansje Henny Vera; Tsegay, Guesh Mebrahtom; Tsegaye, Dejen; Ullah, Sana; Usman, Abachebissa Nuru; Valizadeh, Rohollah; Veroux, Massimiliano; Verras, Georgios-Ioannis; Vos, Theo; Wang, Mei; Wang, Song; Wickramasinghe, Dakshitha Praneeth; Yahya, Galal; Zare, Iman; Zarrintan, Armin; Zhang, Zhi-Jiang; Dirac, M Ashworth
BACKGROUND : Appendicitis is a common surgical emergency that poses a large clinical and economic burden. Understanding the global burden of appendicitis is crucial for evaluating unmet needs and implementing and scaling up intervention services to reduce adverse health outcomes. This study aims to provide a comprehensive assessment of the global, regional, and national burden of appendicitis, by age and sex, from 1990 to 2021. METHODS : Vital registration and verbal autopsy data, the Cause of Death Ensemble model (CODEm), and demographic estimates from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) were used to estimate cause-specific mortality rates (CSMRs) for appendicitis. Incidence data were extracted from insurance claims and inpatient discharge sources and analysed with disease modelling meta-regression, version 2.1 (DisMod-MR 2.1). Years of life lost (YLLs) were estimated by combining death counts with standard life expectancy at the age of death. Years lived with disability (YLDs) were estimated by multiplying incidence estimates by an average disease duration of 2 weeks and a disability weight for abdominal pain. YLLs and YLDs were summed to estimate disability-adjusted life-years (DALYs). FINDINGS : In 2021, the global age-standardised mortality rate of appendicitis was 0·358 (95% uncertainty interval [UI] 0·311-0·414) per 100 000. Mortality rates ranged from 1·01 (0·895-1·13) per 100 000 in central Latin America to 0·054 (0·0464-0·0617) per 100 000 in high-income Asia Pacific. The global age-standardised incidence rate of appendicitis in 2021 was 214 (174-274) per 100 000, corresponding to 17 million (13·8-21·6) new cases. The incidence rate was the highest in high-income Asia Pacific, at 364 (286-475) per 100 000 and the lowest in western sub-Saharan Africa, at 81·4 (63·9-109) per 100 000. The global age-standardised rates of mortality, incidence, YLLs, YLDs, and DALYs due to appendicitis decreased steadily between 1990 and 2021, with the largest reduction in mortality and YLL rates. The global annualised rate of decline in the DALY rate was greatest in children younger than the age of 10 years. Although mortality rates due to appendicitis decreased in all regions, there were large regional variations in the temporal trend in incidence. Although the global age-standardised incidence rate of appendicitis has steadily decreased between 1990 and 2021, almost half of GBD regions saw an increase of greater than 10% in their age-standardised incidence rates. INTERPRETATION : Slow but promising progress has been observed in reducing the overall burden of appendicitis in all regions. However, there are important geographical variations in appendicitis incidence and mortality, and the relationship between these measures suggests that many people still do not have access to quality health care. As the incidence of appendicitis is rising in many parts of the world, countries should prepare their health-care infrastructure for timely, high-quality diagnosis and treatment. Given the risk that improved diagnosis may counterintuitively drive apparent rising trends in incidence, these efforts should be coupled with improved data collection, which will also be crucial for understanding trends and developing targeted interventions.
Using secondary data analysis to compare core vocabulary lists and elicitation duration of two data sets of typically developing preschool Afrikaans-speaking children
(Karger Publishers, 2025) Winter, Petria; Van der Linde, Jeannie; De Wet, Febe; Graham, Marien Alet; Bornman, Juan; jeannie.vanderlinde@up.ac.za
INTRODUCTION : Core vocabulary lists provide an evidence-based method for describing the vocabulary of individuals across various age groups, categorised by different parts of speech. Despite its value, there is a paucity of core vocabulary lists in nonmainstream languages. Resource limitations contribute to this paucity; therefore, more efficient methods for developing core vocabulary lists are needed. This study aimed to compare two sets of previously collected language samples from typically developing 5–6-year-old Afrikaans-speaking children to compare two different elicitation methods for developing a core vocabulary list. We also compared the duration of the language samples to inform the duration required for accurate and representative language samples for the development of core vocabulary lists. METHODS : Using secondary data analysis, we compared the core vocabulary lists from two existing data sets in terms of the number of different words, the frequency of use of each of these words, type-token ratio, and parts of speech used by typically developing 5–6-year-old Afrikaans-speaking children. RESULTS : The average recording time for data set A was 60 min in a single session. The corresponding value for data set B was 250 min, recorded over a period of 1–3 days. A perfect positive Spearman correlation was observed between the results for the two data sets for all parts of speech except interjections and enclitics. Code switching formed part of data set B’s core words but did not appear in data set A’s core word list. CONCLUSION : The findings demonstrate that similar core vocabulary lists can be obtained for 5–6-year-old children using a less invasive and time-effective 60-min elicited method for language samples compared to naturalistic samples collected over 1–3 days. Proposing a more robust and less time- and resource-intensive method of developing vocabulary lists may further support the development of core word lists across ages and in other languages.

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