Research Articles (Animal and Wildlife Sciences)

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This collection contains some of the full text peer-reviewed/ refereed articles published by researchers from the Department of Animal and Wildlife Sciences

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Differential metabolomic effects of progestagen-based estrus synchronisation in South African Dohne Merino ewes
Shingange, Rimbilana N'wa-Nghondzweni; Visser, Carina; Wooding, Madelien; Webb, E.C. (Edward Cottington) (Springer, 2026-07-10)
This study represents one of the first to comprehensively profile the homeostatic cervicovaginal metabolome of South African Dohne Merino ewes using liquid chromatography high resolution mass spectrophotometry (LC-HRMS) and compare that metabolome immediately after estrus synchronisation using progestagen intravaginal pessaries. As the use of assisted reproductive technologies gains traction in various livestock production systems, characterising their effects using novel omics approaches is crucial to physiology, welfare and production. An ewe has well-developed metabolomic cascades that are homeorhetically responsive to the stress caused by assisted reproductive treatments in order to maintain homeostasis. The cervicovaginal fluid of sixty ewes was sampled by transvaginal FLOQSwabs before pessary insertion as well as immediately post-pessary removal. These swabs, along with field, solvent and swab blanks, underwent extraction in acetonitrile and drying under nitrogen prior to reconstitution. Using one-way ANOVA with Tukey's HSD post-hoc analysis and PERMANOVA, this study found no significant metabolomic features prior to treatment (P > 0.05). However, after pessary removal, 32 features were reported to be different between the CIDR-, sponge-treated and control group (P < 0.005 and False Discovery Rate < 0.05). Features were identified at four levels including at verification with pure chemical standards. Progesterone was found to be highest in the CIDR-treated group (P < 5.0 × 10- 48) while linolenic acid, an immune modulator, was highest in the sponge-treated group (P < 5.0 × 10- 3). These findings present a novel understanding of the metabolomic fluctuations that occur within the cervicovaginal microenvironment in response to progestagen synchronisation protocols, which are a routine part of management in the production systems of sheep and various other species of livestock. These stark metabolomic differences highlight endocrine and immune changes that are triggered by the CIDR or sponge and warrant further characterisation of the physiological and welfare implications of these technologies.
Possible factors affecting the bioavailability of copper and the copper requirements of wild, free-ranging African herbivores : a review
Van Ryssen, J.B.J.; Bath, Gareth F. (South African Society for Animal Science, 2025-11-12)
Free-ranging wild herbivores in Africa comprise 78 species of ruminants and several species of monogastric hindgut fermenters, and are classified as grazers, mixed feeders, and browsers. The objective of this review is to provide guidance to wildlife nutrition advisers by outlining key metabolic principles relevant to assessing copper nutrition in herbivores. In domestic species, copper bioavailability is influenced by dietary copper antagonists, copper solubility at absorption sites, and the homeostatic regulation of copper metabolism. Differences in the homeostatic control of copper absorption and metabolism in the liver between ruminants and monogastric species have a major effect on their tolerance to excessive copper exposure. As some elements in the diet are antagonistic to copper solubility in the digestive tract, dietary copper concentration alone has limited diagnostic value for assessing the potential copper nutrition status of a ruminant. Dietary copper is most soluble in acidic environments and factors influencing rumen pH, such as the effect of diet type on rumination and saliva flow, could thus influence copper solubility. In monogastric species, the solubility of dietary copper in the stomach can be high (up to 80% in vitro) because of the acidic environment of the stomach. Consequently, in domestic species, the bioavailability of copper varies from 1% to 10% in mature ruminants, compared with an estimated >30% for non-ruminants. This suggests that for wild species with similar body weights and diets, dietary copper requirements per kilogram of feed intake for maintenance should be substantially lower for monogastric species than for ruminants.
Effects of postpartum energy balance, body condition score, and insemination time on conception rates of Bonsmara cows bred using timed artificial insemination
Webb, E.C. (Edward Cottington); Demont, Kaylee Jade; De la Rey, M.; Theron, H.E. (South African Society for Animal Science, 2025-10-10)
Fertility management of extensively farmed beef cattle in South Africa is essential to ensure the economic viability of such production systems. However, the success of timed artificial insemination (TAI) programmes varies, affecting cattle farmers’ adoption of this reproductive technique. This study investigated the effects of postpartum energy balance (∆M), body condition score (BCS), time of artificial insemination (morning or afternoon), and any interactions on the conception rates of Bonsmara cows (N = 72, second to ninth parity, BCS ≥2.25) in the Limpopo Province of South Africa. The cows were synchronised in the morning or afternoon using the seven-day CO-Synch synchronisation protocol. Cow live weight and BCS were recorded at synchronisation, TAI, and pregnancy determination, and the data were used to calculate the ∆M. Cows that did not conceive from TAI were naturally mated, and the number of cows that did not conceive was recorded. The average conception rate of cows bred by both TAI and natural mating was 76.7 ± 5.60%. The ∆M and time of artificial insemination did not influence the conception rate. The BCS and duration of the postpartum period influenced the conception rates of cows bred by TAI and cows bred by combined TAI and natural mating. Cows that conceived from TAI tended to have higher estimated breeding values for fertility than those that conceived from natural mating or did not conceive. Cows with a BCS of 3.00–3.75 had the highest conception rates, followed by those with a BCS >3.75, with cows with a BCS <2.75 having the lowest rates.
Response of broiler chickens offered choices of feeds varying in calcium and phosphorus concentration from 0 to 21 days of age
Backhouse, Dean; Cowieson, A.J.; Gous, R.M.; Jansen van Rensburg, Christine (Taylor and Francis, 2026-02-05)
1. This study tested the ability of broiler chickens to regulate dietary calcium (Ca) and retainable phosphorus (rP) intake when offered choices of complete diets varying in Ca and rP concentration from 0 to 21 d of age. 2. Males and females were reared separately under standard conditions and offered either a singlediet in some treatments, or in other treatments, a choice of two diets varying in Ca and reconcentration, resulting in 10 dietary treatments. Body weight and feed intake were measured at 7,14 and 21 d. For each choice treatment, the intake of each diet as a proportion of the total intake was determined. Tibial ash concentration, Ca concentration, phosphorus (P) concentration and breaking strength were determined at 21 d. 3. For the choice treatments, in which one diet was low in rP and the other high in rP, feed intake significantly favoured high rP concentration. Body weight gain responded positively to increasing rPintake, apparently regardless of Ca intake, although bone density and structural integrity were maximised when rP and Ca intake were both high. 4. The principle that broiler chickens can select between feedstuffs to achieve intake that maximises growth, and, arguably, fitness, was seen in the diet choice of broiler chickens in the current experiment, at least for dietary Ca and rP.
Starter phase broiler response to Moringa oleifera leaf meal, a three-strain Bacillus probiotic, or butyric organic acid as alternatives to antibiotic growth promoters
Nduku, Xola; Nkukwana, Thobela T. (Taylor and Francis, 2026)
This study investigated the effects of replacing in-feed AGPs with either Moringa oleifera leaf meal (MOLM), a three-strain Bacillus probiotic, or a coated butyric acid on the growth performance, digestive organ size and intestinal morphology of broiler chicks during the starter phase (0–14 days). Day-old, mixed-sex Cobb 500 broiler chicks (n = 300) were randomly allocated to experimental pelleted basal starter diets containing (1) 300 g/ton zinc bacitracin and 500 g/ton salinomycin (positive control; PC), (2) 1000 g/ton MOLM, (3) 500 g/ton three-strain Bacillus probiotic (PROB), (4) 1000 g/ton coated butyric acid (ORGA) and (5) no additives (negative control; NC). At d7 and d14, PC birds had higher bodyweights and FCR, followed by ORGA and PROB fed birds. MOLM fed birds had the heaviest small intestines (p < 0.05), while the NC group had the lightest; with heaviest (p < 0.05; 9.67) caecum in both the MOLM and NC birds compared to those in the PC (9.33), ORGA (7.00) and PROB (7.00). Jejunal villi length was significantly longer (p < 0.05) in the NC birds (511.37) then MOLM (505) and PC had the shortest (348.75). The three AGP alternatives tested showed optimum response in production parameters and beneficial effects on intestinal development, highlighting their potential as a functional feed additive in early broiler growth. Additionally, with high hygienic-biosecurity standards, NC treatment can be just as effective.
Peanuts and peanut butter consumption patterns and consumer perceptions among mid and lower income urban South Africans
Muller, Carmen; Pretorius, Beulah; Schonfeldt, H.C. (Hettie Carina) (Springer Nature, 2026-06-21)
Peanuts (Arachis hypogaea) are a nutrient-dense, affordable food with the potential to support nutrition security and mitigate diet-related health risks in South Africa. Despite their widespread availability, little is known about consumer knowledge, attitudes, and practices regarding peanut consumption among lower- and mid -income urban populations. This cross-sectional study assessed peanut and peanut butter consumption patterns, purchasing drivers, cultural perceptions, and product knowledge among 214 adults (≥ 21 years) in Gauteng province. Data were collected via a pre-tested, face-to-face questionnaire and analysed using descriptive statistics, thematic coding, and Pearson’s chi-square tests. Peanut butter was identified as a widely consumed household staple, driven by taste, affordability, convenience, and perceived health benefits. Whole peanuts were consumed in roasted or boiled forms and predominantly sourced from informal vendors, while peanut butter was primarily purchased from supermarkets, highlighting retail segmentation. Taste and price were the main drivers of consumption, whereas textural preferences and eating experience influenced non-consumption of certain peanut forms. Although peanuts were frequently consumed across age groups, many participants did not perceive them as part of their cultural eating patterns, despite intergenerational exposure during childhood. Consumer awareness of nutritional information and food safety issues, including aflatoxins, was limited, and exposure to marketing or educational messaging was low. These findings underscore the potential of peanuts as a culturally familiar, affordable, and nutritionally valuable food that can contribute to public health objectives. Targeted interventions, including culturally relevant messaging, recipe-based guidance, and nutrition education, could enhance consumer knowledge, support healthier dietary practices, and strengthen food system engagement within economically vulnerable urban populations.
A narrative review of the implementation and monitoring of the food-based dietary guidelines within the healthcare sector in South Africa
Dimo, Raisibe P.; Muchiri, Jane Wanjiku; Shirinde, Joyce; Schonfeldt, H.C. (Hettie Carina) (Springer Nature, 2026-06-18)
BACKGROUND : Food-based dietary guidelines (FBDGs) are a public health nutrition intervention that plays a crucial role in promoting healthy eating habits and preventing nutrition-related diseases in the population. OBJECTIVES : To synthesise evidence on the implementation and monitoring of FBDGs with respect to nutrition education in healthcare settings and the influence on dietary patterns and behaviour in South Africa (SA). DESIGN AND SETTINGS : A narrative review was conducted. A comprehensive search strategy was used to identify relevant literature tailored to Africa-Wide Information, CINAHL, MEDLINE via EBSCOHOST, PubMed and ScienceDirect. The selection criteria were based on the Population, Intervention, Control, Outcome and Time (PICOT) framework. The search was focused on SA (97 literature). After removing 43 duplicates, a total of 54 research articles were screened. In the data extraction phase, six articles and six reports were selected. The results of these studies were compared and narratively described in relation to the objectives. RESULTS AND DISCUSSION : The review revealed a few studies focusing on the implementation and monitoring of FBDGs in SA. Despite improved dissemination of FBDGs, gaps posed by the lack of monitoring persist. After nearly 25 years of SA adopting FBDGs, and more than 10 years of adopting a revised version of FBDGs, the implementation and impact of FBDGs remain uneven and under-evaluated. There is a notable lack of a standardised FBDGs monitoring tool and reporting. CONCLUSION AND IMPLICATIONS : Given the identified gaps in both implementation and monitoring, there is a need for a structured and context-specific monitoring framework that integrates clear indicators, standardised data collection systems, and accountability mechanisms within the South African health sector.
Remote sensing for forage ratio estimation : a systematic review
Rapiya, Monde; Ngcoliso, Nasiphi; Truter, Wayne; Ramoelo, Abel (Taylor and Francis, 2026)
Remote sensing has emerged as a vital technology for monitoring vegetation dynamics and ecosystem health, particularly in assessing forage quality and quantity. This study investigates the application of remote sensing tools for forage ratio estimation. A bibliometric analysis was conducted in RStudio (v4.0.4), biblioshiny using datasets obtained from the Dimensions, Scopus and Web of Science (WoS) databases, covering the period from 2005 to 02/2025 and guided by the PRISMA approach. The analysis indicates a generally low but steadily increasing research output, with notable peaks observed in 2014, 2020 and 2023. Notably, significant progress in remote sensing technologies particularly hyperspectral and multispectral imagery has enhanced the capacity to accurately estimate key forage quality parameters, including Carbon:Nitrogen (C:N) and Nitrogen:Phosphorus (N:P) ratios. Machine learning algorithms, especially random forest models, have proven effective in improving predictive accuracy for forage quality assessments. Despite these technological strides, research remains concentrated in the Northern Hemisphere, with limited contributions from developing nations, particularly in the Southern Hemisphere, highlighting a critical geographic disparity. Our keyword analysis further underscores a growing trend towards integrating machine learning with remote sensing to monitor forage ecosystems. This review calls for enhanced international collaboration and investment in underrepresented regions, emphasizing the necessity for equitable access to remote sensing technologies. As ecological challenges intensify, the continued exploration of remote sensing methodologies for forage ratio assessment is crucial for promoting sustainable land management practices and wildlife conservation efforts. Future research should focus on refining predictive models and expanding applications across diverse ecosystems, thereby maximizing the potential of remote sensing in effective forage ecosystem management.
Piglet birth weight predicts grow-finish performance despite dietary lysine adjustment
Akuru, Eunice Amaka; Nel, Cara; Steyn, Willem Johannes; Jansen van Rensburg, Christine (Elsevier, 2026-06)
Piglet birth weight is a key determinant of postnatal growth performance and carcass quality in commercial pig production. This study evaluated whether piglet birth weight predicts grow–finish performance and whether low-birth-weight (LBW) pigs respond differently to dietary standard ileal digestible (SID) lysine levels, compared with heavy-birth-weight (HBW) pigs. A total of 144 pigs (72 LBW: 0.9–1.2 kg; 72 HBW: 1.7–2.0 kg at birth) were selected at 70 days of age and allocated to a 3 × 2 × 2 factorial design, including three dietary SID lysine levels (control, +10%, and −10%), two birth weight categories, and two sexes. Pigs were fed isocaloric maize-soybean-based diets during a 77-day grow–finish period. Growth performance was recorded weekly, and carcass traits were measured at slaughter (147 days of age). Birth weight significantly influenced body weight and average daily gain, with HBW pigs remaining heavier throughout the experimental period up to slaughter. Dietary SID lysine did not influence growth performance or carcass traits within birth weight groups. During the finisher phase, HBW pigs increased feed intake when fed the low-lysine diet, whereas LBW pigs reduced intake and exhibited improved feed conversion ratio without affecting growth rate. HBW pigs produced heavier carcasses with greater backfat thickness, while lean meat percentage was unaffected by birth weight or dietary lysine level. Sex effects on carcass traits were observed primarily under low-lysine conditions. These findings confirm that piglet birth weight remains a strong predictor of finishing performance, indicating that moderate adjustments in dietary lysine supply from 70 days of age are insufficient to overcome growth limitations associated with low birth weight. HIGHLIGHTS • Piglet birth weight consistently predicted, grow-finish growth performance. • Dietary lysine adjustment did not improve the performance of LBW pigs. • LBW pigs showed limited feed intake response to reduced dietary lysine. • HBW pigs compensated for low lysine diets by increasing feed intake. • Early-life constraints limit the effectiveness of nutritional intervention.
Influence of dietary non-essential amino acids to lysine ratio on egg performance and body composition of brown-egg layers from 20 to 35 weeks of age
Coertze, Gerhard; Kwakkel, Rene; Star, Laura; Jansen van Rensburg, Christine (Public Library of Science, 2025-11-07)
Limited published data are available on the ratio of digestible non-essential amino acid (DNEAA) to digestible lysine (DLys) for layers. The effect of different DNEAA-to-DLys ratios on performance parameters of Hy-Line Silver-Brown layers was studied from 20 to 35 weeks. Experimental design was randomized with ten dietary treatments of increasing concentrations of DNEAA-to-DLys ratio (10.61, 10.84, 11.08, 11.31, 11.54, 11.77, 12.00, 12.23, 12.46, 12.69). Average daily feed intake, total feed intake, laying rate, cumulative egg number, egg weight, hen body weight, feed conversion ratio, egg mass output, albumen weight, eggshell weight, yolk weight, eggshell breaking strength, eggshell thickness, carcass and feather weight, carcass protein, carcass fat, liver weight, and liver fat were recorded. Changing the DNEAA/DLys ratio did not affect production parameters. Yolk and yolk-to-egg weight decreased with an increase in DNEAA/DLys ratio, while albumen-to-yolk and albumen-to-egg weight increased. The DNEAA/DLys ratio did not affect carcass or liver composition, but liver and liver-to-body weight (%) decreased as the DNEAA/DLys ratio increased. Hy-Line Silver-Brown layers during peak production sustained egg production and quality even on the lowest ratio in this study. Low DNEAA/DLys ratios increased liver fat deposition.
Feeding practice and its association with nutritional status of infants aged 0–6 months in Endumeni sub-district, South Africa
Khosa, Thomson; Napoles, Lizeka; Pretorius, Beaulah (Elsevier, 2026-02)
BACKGROUND : Inappropriate infant feeding practices contribute significantly to malnutrition, which underlies approximately 54% of global infant mortality. This study examined feeding practices and their association with nutritional status among infants aged 0–6 months attending well-baby clinics in Endumeni, KwaZulu-Natal, South Africa. METHODOLOGY : A cross-sectional study was conducted in 2023 involving 329 mothers or primary caregivers (aged 18–40 years) of infants aged 0–6 months from nine clinics. Data were collected using structured questionnaires and analyzed using Stata. Associations between feeding practices and infant nutritional status were assessed using Chi-square tests. RESULTS : Among the infants, 49.9% were male and 50.1% female. Most (49.5%) were between 1–4 months old. Breastfeeding was reported in 72.0% of infants, with 36.8% exclusively breastfed. Formula feeding occurred in 28.0% (22.7% exclusively and 5.3% mixed-fed). Among those introduced to complementary feeding, common first foods included soft porridge (39.5%), commercial baby foods (10.9%), and water (3.0%). Nutritional assessments indicated that 59.3% had normal weight-for-age, while 26.8% were overweight, 4.6% obese, 4.6% underweight, and 4.3% severely underweight. A significant association was found between feeding practices and nutritional status (P < 0.05). Notably, 82.6% of breastfed infants had normal weight, whereas non-breastfed infants were overrepresented in both undernutrition and overweight categories. CONCLUSION : Breastfeeding was positively associated with optimal anthropometric outcomes in early infancy, suggesting a protective effect against both under- and overnutrition. Strengthening caregiver education and breastfeeding support should be prioritized in infant nutrition interventions and policy. HIGHLIGHTS • 63.5% of infants were currently breastfed; 36.8% exclusively breastfed. • Exclusive breastfeeding and formula feeding were nearly equally prevalent. • 56.5% of infants received early complementary foods, mainly porridge and water. • Non-breastfed infants showed higher rates of severe underweight or obesity. • 19.5% of caregivers lacked knowledge of appropriate complementary foods.
A bibliometric assessment of urban agriculture indexed in Scopus and Wos from 1978-2023
Idamokoro, Emrobowansan Monday; Niba, Augustine Suh; Akuru, Eunice Amaka (Science Publications, 2025-09)
Urban agriculture is a system of food production in and around urban settlements aimed at ameliorating the challenge of food shortage. The goal of this study is to explore emergent worldwide publication trends, contemporary focus and gaps in urban agriculture research over the last four decades (1978-2023). Despite the numerous research work on urban agriculture, gap existed in literatures on a research to qualitatively quantify the collective global outputs of studies done on urban agriculture. A Bibliometric approach was employed to analyse the research publications extracted from the combination of WoS and Scopus data banks. A total of 3817 articles were recovered from these two databanks with an average citations per doc and co-authors per document ratio of 18.34 and 3.29, respectively. Studies on urban agriculture researches were positively correlated with the number of years (R2 = 0.6507; y = 7.5651x - 95.562) suggesting a rise in the number of publications on the subject matter. The USA was ranked in the top position in terms of outputs and citation numbers (n = 605; 15612), followed by China (n = 284; 4648) and Germany (n = 181; 4786). The study indicated that urban agriculture is increasingly attracting global attention with an impressive rise in research publications from 2002 to 2023. The investigation on urban agriculture is mostly carried out in financially stable economies with minimal representations from developing nations and institutions. Some main emphasis and hotspot within the field of urban agriculture research is tailored towards food security, urban farming, urban gardening, sustainability, community gardening and climate change with minimal work on research in the aspects of policy and governance, thus signifying the direction for future investigations.
Kinship and network analysis of two South African beef cattle breeds using pedigree and high-density SNP markers
Khanyile, Khulekani S.; Maiwashe, Azwihangwisi; Magagula, Nozipho A.; Van Marle-Koster, Este; Zwane, Avhashoni Agnes (MDPI, 2026-03-19)
Accurate genealogical records are essential in livestock breeding for maintaining genetic diversity, preventing inbreeding, and mapping of economically important traits in beef production. This study aimed to assess parent–offspring relationships within South African Bonsmara and Nguni cattle populations using both traditional pedigree records and genomic data. Hair samples from 119 Nguni and 311 Bonsmara cattle were genotyped using the BovineSNP50 array, and these were imputed to Illumina BovineHD BeadChip using updated SNP coordinates from the assembly genome (ARC—UCSD 1.2). Quality control and data filtering were performed using PLINK v1.9, while relationship inference was conducted using KING v2.2.8 and PLINK v1.9 software for principal component analysis, IBD metrics and Mendelian error-based exclusion. Categories of relatedness through network relationship analysis revealed a predominance of half-sibling relationships in both breeds, with 2317 such relationships identified in Nguni and 1221 in Bonsmara. Inference of parent–offspring pairs showed discrepancies with the recorded pedigrees, with 49 inferred pairs compared to 47 recorded pairs in Nguni, and 62 inferred pairs compared to 75 pairs recorded in Bonsmara. Relationships based on IBD using PLINK with a ‘PI-HAT’ threshold greater than 0.45 revealed unique parent–offspring inferences that differed from those obtained using KING v2.2.8. Phylogenetic network analysis assigned each individual’s genomic origin independent of the pedigree records, supporting the efficiency of SNP data for genetic assignment. These results demonstrated that SNP-based pedigree verification can accurately identify parent–offspring and half-sibling relationships, providing a reliable foundation for recombination analysis and supporting precise trait mapping and informed selection in breeding programs.
Measurement of pregnancy rate and foetal loss, and their associations with management practices on reproductive performance of smallholder beef cattle heifers in South Africa
Nkadimeng, Marble; Van Marle-Koster, Este; Nengovhela, Nkhanedzeni B.; Ramukhithi, Fhulufhelo V.; Rust, Johannes M.; Makgahlela, Mahlako L. (Springer, 2026-03)
Understanding reproductive performance of replacement heifers is pivotal for sustainable and profitable farming in any cattle production system. The study assessed reproductive performance of smallholder beef cattle heifers focusing on pregnancy rate (PR); and fetal and calf loss (FCL). Additionally, it investigated herd management factors that influence these traits. A total of 538 heifer records were collected from 40 herds representing five provinces between 2018 and 2019. A secondary application of established seasonal pregnancy diagnosis methods was used to measure PR and FCL. Management factors including body condition score (BCS), age at first mating and calving, breed type, heifer selection, record-keeping, frame size, breeding and calving season were recorded. The Kaplan-Meier method analysed reproductive outcomes, while the Cox proportional hazards model assessed management factors influencing PR and FCL. Results indicated an average of 47% PR and 11% FCL with achievable levels of 60% PR and 0.9% FCL. Majority of heifers conceived between ages four and five years. At three years, 96.19% of heifers had not experienced loss, however, the calf survival probability decreased to 68.17% by five years. The median age for first calving was four, by age five, 72.96% of heifers had calved. The results showed significant effects (P < 0.05) for breed type, breeding season, BCS, frame size and heifer selection on PR and FCL. Optimizing PR and FCL in smallholder heifers may depend on improving management practices including selection practices of heifers prior to breeding, maintaining optimum BCS and breeding during favourable environmental conditions.
Comparative proximate analysis and nutrient labelling compliance of cow milk and plant-based milk alternatives : implications for consumer choice and food policy
Pieterse, Elaine; Pretorius, Beulah; Schonfeldt, H.C. (Hettie Carina) (Elsevier, 2026-02)
This study compared the nutritional composition of cow milk and plant-based milk alternatives (PBMAs) available in South African retail markets and assessed nutrient labelling compliance. Proximate and mineral analysis was conducted on 60 PBMA samples (soy, almond, oat, rice, coconut) and 39 cow milk samples using standardised analytical methods. Results demonstrated significant nutritional differences between product categories (p < 0.05). Cow milk demonstrated significantly higher nutrient density, particularly for protein and key bone-building minerals including calcium, phosphorous, and zinc. Conversely, PBMAs showed higher iron, copper, and manganese levels, though bioavailability may be compromised by antinutrients. Labelling non-compliance was identified for calcium and dietary fibre overreporting for PBMAs, and sodium underreporting across both categories. These findings indicate that PBMAs are not nutritionally equivalent to cow milk and highlight the need for improved regulatory oversight of nutritional labelling to prevent consumer misinformation. HIGHLIGHTS • First comprehensive proximate analysis of South African retail PBMAs. • PBMA labels overreported calcium and dietary fibre, and underreported sodium. • A typical 200 ml serving of PBMAs provides less than 0.2 g fibre. • Cow milk maintains optimal Ca:P ratios (1.09–1.44) versus imbalanced ratios in PBMAs.
Whole-genome sequencing reveals genomic diversity and selection signatures for adaptation in South African Afrikaner and Bonsmara cattle
Alberts, Daniélle; Van Marle-Koster, Este; Joubert, F.; Berry, Donagh P. (Frontiers Media, 2026-02)
The indigenous Afrikaner and composite Bonsmara cattle breeds are hardy and adapted to the diverse South African climate and biomes. Both breeds have been successfully used in the South African stud and commercial industries. This study explored the genomic diversity and population structure, as well as identified selection signatures within and between the Afrikaner and Bonsmara breeds with a focus on signatures related to adaptation traits. Short-read whole genome sequencing data of 42 Afrikaner and 43 Bonsmara cattle were analysed. Diversity analysis revealed comparable nucleotide diversity levels in the Afrikaner and Bonsmara populations, with the Bonsmara having weaker average linkage disequilibrium between adjacent single nucleotide polymorphisms as well as having fewer runs of homozygosity. Furthermore, genetic structure analysis revealed distinct clustering of both populations, with the exception of a subset of Afrikaner individuals having been infused with Bonsmara genetics. Between and within breed selection signatures were detected using the fixation index and integrated haplotype score approaches, respectively. Several gene ontology terms were described based on the detected selection signatures, with the most significant being nervous system development and multicellular organismal processes. Finally, functional annotation of the candidate genes from the within-breed selection signature analysis revealed several genes (B3GLCT, HSPA2, HSPH1, STING1) relating to adaptive traits in both populations. The location of the within and between breed selection signatures in this study population is consistent with the performance and adaptive characteristics of both breeds and may enhance future breeding strategies with the inclusion of these breeds in crossbreeding programs. Furthermore, a comprehensive genomic characterization of these breeds through whole genome sequencing data is important as these adapted breeds are valuable reservoirs of genetic variation.
Phenotypic and genetic analyses of claw lesions in TMR Holstein herds in South Africa
Joubert, Robyn Clair; Mostert, Bernice Euodia; Masenge, Andries; Van Marle-Koster, Este (Copernicus Publications, 2026-01-07)
Claw lesions in dairy cattle pose a significant risk to dairy farmers worldwide in terms of animal welfare concerns and economic profitability. However, the use of different data sources, classification systems, and definitions of reference groups limits the comparison across herds and decreases the usability of the recordings for phenotypic and genetic analyses. In South Africa, information on claw lesions is not routinely collected by dairy farmers and data are limited to hoof trimmers recording lesions during preventative trimming or as needed by producers. Records of the most common claw lesions scored by a local hoof trimmer in five Holstein herds between January 2014 and December 2023 were used, including interdigital phlegmon (F), heel horn erosion (E), sole ulcers (SU), sole haemorrhage (SH), and two combined traits, one representing digital and interdigital dermatitis (DDID) and the other representing white line disease and white line separation (WLDS). The majority of lesions recorded were infectious (40.87 %), with DDID showing the highest incidence (39.58 %). Phenotypic associations may provide valuable information for hoof trimmers regarding the practical prevention, management, and treatment of lameness on-farm. A large, statistically significant odds ratio of 4.39 exists between DDID and E (95 % confidence interval: 3.55 to 5.43, P<0.0001). Within the non-infectious lesions, SH is moderately positively associated with total non-infectious lesions (|ϕ|=0.43, P<0.01) and the occurrences of SU and WLDS are both strongly positively associated with total non-infectious lesions (|ϕ|=0.54, P<0.01 and |ϕ|=0.58, P<0.01, respectively). In addition, the relationships observed among non-infectious lesions (SH, SU, and WLDS) are moderate to strong. The occurrence of DDID is moderately positively associated with the occurrence of infectious lesions in the front feet (|ϕ|=0.39, P<0.01) and strongly associated with the rear feet (|ϕ|=0.89, P<0.01). The occurrence of WLDS is moderately positively associated with the occurrence of total non-infectious lesions in the front feet (|ϕ|=0.37, P<0.01), with a stronger correlation with the occurrence of non-infectious lesions in the rear feet (|ϕ|=0.46, P<0.01). The occurrence of non-infectious lesions in the rear feet is moderately associated with the occurrence of SU (|ϕ|=0.42, P<0.01) but strongly associated with SH (|ϕ|=0.57, P<0.01). Heritability estimates ranged from 0.02 for DDID to 0.08 for the total lesions category (representing the presence or absence of at least one claw lesion on any foot). Phenotypic correlations and heritability estimates indicate that claw lesion data have the potential to be used for genetic evaluation of hoof health; therefore, the simplification and standardization of hoof lesion data collection should be encouraged.
Sustainable nutrient management strategies for enhancing potato production : the role of cover crops - a systematic review
Xaba, Sbonile; Bello, Zaid; Rapiya, Monde; Ngobese, Nomali Ziphorah (MDPI, 2025-09-03)
The global demand for agricultural products, like potatoes, is increasing due to population growth, so we must use more sustainable farming methods. Traditional potato farming often relies too much on synthetic fertilisers, which can harm the environment and lead to inefficiencies. This study examines how different cover crops (like legumes) affect potato yields and quality, and their benefits for soil health. It also explores why farmers do not always use cover crops. This study found that using leguminous cover crops can increase potato yields by 12–38%, improve soil structure, reduce erosion and greenhouse gas emissions, and help with water retention. Cover crops also increase soil organic matter and help with nutrient cycling, making farming more sustainable. However, some farmers are hesitant to adopt cover crops because of concerns about yield risks and higher labour costs. To overcome these barriers, this study suggests educating farmers about the long-term benefits, providing financial incentives to help with the costs, and creating region-specific guidelines for using cover crops. Policymakers and agricultural organisations should encourage farming practices that focus on soil health and using resources efficiently. By addressing these challenges, we can make sustainable potato farming more common, helping ensure food security and environmental sustainability, especially with climate change.
Beef tenderizing potential of Solanum dubium (Gubbain) protease
Biraima, Ahmed Dayain Abdalla; Webb, E.C. (Edward Cottington) (Iowa State University Digital Press, 2025)
This study aimed to evaluate the efficacy of Solanum dubium protease extract injection in tenderizing beef m. longissimus thoracis et lumborum (LTL). A total of 12 LTL muscles were obtained from 6 carcasses (from both left and right sides) at 24 h postmortem, and each muscle was divided into 2 equal samples to yield 24 samples (n = 12/treatment). Samples were then randomized to receive either an injection with S. dubium protease extract (at 10% of muscle weight) or no injection (control). After 24 h of incubation, the muscle was analyzed for color, sarcomere length (SL), myofibril fragment length (MFL), Warner-Bratzler shear force (WBSF), collagen solubility, quantification of meat degradation, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The injected muscles with the S. dubium protease extract yielded lower (P < .001) WBSF values with a better L* (P < .05) compared with samples of the control muscles. The results of MFL and the quantification of meat degradation reflected the great ability of the protease extract to degrade myofibrillar proteins. Collagen was hydrolyzed significantly by the protease extract. SDS-PAGE showed the presence of several new lower molecular weight bands after treating muscle with the protease extract. WBSF was significantly related to SL, MFL and collagen solubility. The protease enzyme from S. dubium seeds may be a novel and promising option as a meat tenderizer.
The effects of environmental and management factors on the quality of the corpus luteum and subsequent conception rates of beef and dairy cows in South Africa
Demont, Kaylee Jade; Webb, E.C. (Edward Cottington); Treadwell, Robert; Masenge, Andries (MDPI, 2025-10-30)
The corpus luteum (CL) controls the success of pregnancy. The current study investigated the effects of some environmental and management factors on the development of the CL and the subsequent impact on conception rates of beef and dairy cows in South Africa. Cows (Jersey, Holstein, Nguni, Bonsmara, Tuli, Ankole, Charolais and Angus crosses) receiving an embryo were synchronized based on the breed type and status. Standing estrus was observed from day 9 to day 12 after synchronization. Embryo transfer occurred on day 18. CLs were graded based on size and consistency of each CL by an experienced veterinarian. Production type (beef versus dairy types) was marginally associated with conception after the first synchronization cycle (p = 0.065). Cows were moved between groups, and this influenced the CL (p = 0.08). Climatological factors, maximum THI (p = 0.017) and precipitation (p = 0.061) influenced the quality of the CL in dairy cows. By contrast, precipitation (p = 0.067) influenced the quality of CLs in beef cows. More attention needs to be paid to the management of maximum THI and shelter from precipitation in dairy production systems, while precipitation alone was more important in beef cows. Climate affects the corpus luteum quality of cows of different production types differently.

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