Journal Articles
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Item Seasonal Effects and Heritability of Litter Size at Birth and Weaning in Commercial Rabbits in Central Mexico (2015–2021)(MDPI (Basel, Switzerland), 2025-11-01) Parra-Bracamonte GM; Becerril-Martínez L; Sánchez-Dávila F; Esparza-Jiménez S; Albarrán-Portillo B; García-Martínez A; López-Villalobos N; Vázquez-Armijo JF; Mancini SReproductive performance in rabbits is highly sensitive to seasonal environmental variation and management practices, while the proportion of variance attributable to additive genetics for litter-level traits is typically low. The objective of this study was to evaluate the effects of year and season on litter size at birth (BR), litter size at weaning (WR), and weaning rate (WT), and to estimate the heritability of these traits in a commercial rabbit farm. A total of 770 kindling events recorded between 2015 and 2021 were analyzed. The mixed model for BR included the fixed effects of year and season, and the random effects of sire and residual error. The model for WR included the same structure, with BR added as a covariate. Least-squares means for fixed effects were used for pairwise comparisons using Tukey’s test. Year and season effects were significant for BR (p < 0.005), and the year effect was also significant for WR (p < 0.021). Litter size at birth ranged from 7.80 (dry season) to 9.21 (year 2020), with higher means observed during the semi-dry (8.52) and humid (8.56) seasons compared to the dry season (7.80). Litter size at weaning varied between 4.65 and 5.81 kits depending on the year. Weaning rate showed interannual variation (56.1–68.2%), but seasonal differences did not reach statistical significance (p < 0.075). Heritability estimates from the sire variance component were low: 0.01 for BR, 0.04 for WR, and 0.05 for WT. These results indicate that phenotypic variation in prolificacy in this population was predominantly driven by interannual and seasonal environmental factors, as well as perinatal management practices, while the additive genetic contribution was marginal.Item Mathematical models of the colonic microbiota: an evaluation of accuracy using in vitro fecal fermentation data(Frontiers Media S A, 2025-09-25) Geniselli da Silva V; Smith NW; Mullaney JA; Roy NC; Wall C; McNabb WC; Huang HTraditional approaches for studying diet-colonic microbiota interactions are time-consuming, resource-intensive, and often hindered by technical and ethical concerns. Metagenome-scale community metabolic models show promise as complementary tools to overcome these limitations. However, their experimental validation is challenging, and their accuracy in predicting colonic microbial function under realistic dietary conditions remains unclear. This study assessed the accuracy of the Microbial Community model (MICOM) in predicting major short-chain fatty acid (SCFA) production by the colonic microbiota of weaning infants, using fecal samples as a proxy. Model predictions were compared with experimental SCFA production using in vitro fecal fermentation data at the genus level. The model exhibited overall poor accuracy, with only a weak, significant correlation between measured and predicted acetate production (r = 0.17, p = 0.03). However, agreement between predicted and measured SCFA production improved for samples primarily composed of plant-based foods: acetate exhibited a moderate positive correlation (r = 0.31, p = 0.005), and butyrate a trend toward a weak positive correlation (r = 0.21, p = 0.06). These findings suggest that the model is better suited for predicting the influence of complex carbohydrates on the colonic microbiota than for other dietary compounds. Our study demonstrates that, given current limitations, modeling approaches for diet-colonic microbiota interactions should complement rather than replace traditional experimental methods. Further refinement of computational models for microbial communities is essential to advance research on dietary compound-colonic microbiota interactions in weaning infants.Item Sensitivity analysis of global food and nutrition modelling(Springer Nature B V on behalf of the International Society for Plant Pathology, 2025-10-18) Shippey D; Vignes M; McNabb WC; Smith NWComputational models are often used to explore the future of the global food system, including the implications for human nutrition, an essential aspect of sustainability. However, the confidence that can be placed in the outputs of these models is often poorly quantified. Here, a sensitivity analysis of the DELTA Model® - a linear mass balance model calculating global nutrient supply using global and regional food balance sheet, processing, waste, inedible portion, composition, and bioavailability datasets - is conducted. First, a one-at-a-time analysis, varying 4019 underpinning datapoints from the above datasets individually by ± 50% was conducted to identify those with the greatest impact on calculated global nutrient supply. The most influential values from this initial analysis were then carried forward into a multiple value sensitivity analysis, where all possible combinations of ± 50% variations were simulated. Values related to cereals supply, waste, and nutritional value were the most influential on model output, with selenium, cystine, and carbohydrate supply the most sensitive nutrients. When compared to global nutrient requirements, variations in the calculated supply of some nutrients led to qualitative changes from a sufficient global supply to an insufficient supply. These results, while indicative rather than precise estimates of uncertainty, emphasise the critical importance of accurate cereals data in food system models, provide insight on the degree of sensitivity of similar linear models, and should encourage broader application of sensitivity analysis in the field.Item Harvesting optimization and Omega-3 recovery improvement from Schizochytrium DT3 using surfactant-aided dispersed air flotation: Response surface methodology(Elsevier B.V., 2024-06) Alhattab M; Puri MMicroalgae's potential to produce high value bioactives is contingent on the cost-effective harvesting of algal biomass. The use of CTAB (cetyl trimethylammonium bromide) assisted dispersed air flotation as a harvesting technique for Schizochytrium biomass, was optimized as a cost-effective means for recovery (R) and concentration factor (CF) using Response Surface Methodology. To the best of our knowledge, this is the first study to employ surfactant assisted dispersed air flotation (SDAF) in the recovery of a heterotrophic thraustochytrid strain. A Box-Behnken design of experiment investigating the operating parameters of CTAB amount, air flow rate and volume on Schizochytrium was employed. Initially, both responses were analyzed individually and then used to simultaneously maximize both variables. The optimized conditions of CTAB (500 mg/L), air flow of 2 L/min and volume of 600 mL resulted in a R of 91 % and CF of 19 times. Although a secondary step is necessary for further concentration, this technique utilizes 70 times less energy as compared to conventional centrifugation techniques which are used to recover Schizochytrium sp. This is significant as this technique can be easily adapted to existing bioreactors, as they are already equipped with gas spargers. In addition, the presence of surfactant carried through demonstrated an improvement in the recovery of long chain poly unsaturated fatty acid (PUFA) by 6 %, particularly in DHA and DPA which was not observed in washed biomass.Item Nutritive value of fodder beet for broilers chickens(Elsevier B V, 2026-01-15) Ganraj K; David LS; Morel PCHAn experiment was conducted to determine the apparent metabolisable energy (AME), nitrogen-corrected AME (AMEn) and the standardised ileal digestible content of amino acids in fodder beet (FB). Three maize-soybean-based diets were formulated, a basal diet (FB0), the basal diet supplemented with 12.5 % of FB (FB12.5), and the basal diet supplemented with 25 % of FB (FB25). Each diet was randomly allocated to six replicate cages with six birds per cage and fed from days 14–21. Titanium dioxide (4 g/kg) was included in all diets as an indigestible marker for the measurement of marker-based AME and ileal nutrient digestibility. The total collection (TC) method was also used for the measurement of AME. A regression method was used to determine the nutritive value of FB. The AME and AMEn of FB were determined to be 9.63 MJ/kg and 9.36 MJ/kg, respectively, using the TC method, and 7.97 MJ/kg, 7.79 MJ/kg, respectively, using the marker method. The apparent ileal crude protein (CP) and gross energy (GE) content of FB were 56.4 g/kg and 11.2 MJ/kg, respectively. Standardised ileal digestible amino acid content was higher for glutamic acid (21.1 g/kg) while it was lower for sulfur containing amino acids (-0.1 to −0.4 g/kg). In conclusion, nutritive value of FB was determined for 14–21 day old broilers using regression method. Further studies are needed to validate the current findings, and to determine the optimal inclusion level of FB in poultry diets.Item Modeling the role of institutional trust to improve vaccine confidence: The New Zealand case(Taylor and Francis Group, 2025-07-03) Diers-Lawson A; Ashwell D; Murray NThis study explores how institutional trust influences vaccine confidence during public health crises, using New Zealand’s COVID-19 response as a high-trust case study. Applying the Stakeholder Relationship Management (SRM) framework, the research investigates how demographic, value-based, health, institutional, and informational factors shape vaccine attitudes across varying levels of institutional trust. Results demonstrate that institutional trust is a critical predictor of both vaccine confidence and skepticism, with trust in science and reliance on official sources driving confidence, and social media reliance correlating with skepticism. Segmenting participants by trust levels revealed distinct patterns, highlighting the importance of tailoring communication strategies to trust-based subgroups. The findings reposition vaccine hesitancy as a crisis and risk communication challenge—rooted not solely in individual traits but in institutional relationships and the complex information environment. The study advocates for integrating strategic communication principles into public health risk communication, emphasizing long-term trust-building, credibility, and message alignment across platforms. This research offers a model for cross-contextual testing and underscores the need for governments and health authorities to engage low-trust communities more effectively, particularly through strategic use of social media during health emergencies.Item Testing and adapting dietary habits and food security questions for a national nutrition survey using cognitive interviews and expert consultation(Cambridge University Press on behalf of The Nutrition Society, 2025-10-06) Follong B; Haliburton C; Grey J; Maiquez M; Mackay S; Te Morenga L; Mhurchu CNObjective: To cognitively test questions for inclusion in a national nutrition survey, ensuring the questions are interpreted as intended and to inform further improvements. Design: A draft nutrition survey questionnaire was developed based on existing questionnaires and expert input. Twelve questions on dietary habits and food security were selected for cognitive testing as these were newly developed, amended from existing questions, or identified to no longer reflect the current food environment or concepts. Cognitive interviews were conducted using both think-aloud and probing techniques to capture respondents’ thought processes used to arrive at an answer. Interviews were audio recorded and transcribed verbatim. Qualitative data were analysed for recurring patterns and unique discoveries across the survey questions. Setting: New Zealand. Participants: Sixty-eight participants aged 11 years and older representing diverse sociodemographics including gender, ethnicity, and education level. Results: Three main cognitive challenges were identified: 1) interpreting ambiguous terms, 2) understanding of dietary or technical terms, and 3) following complex or unclear instructions. Questions were refined based on the study findings and further advice from experts in nutrition and survey design to enhance participant understanding and accuracy. Conclusion: The cognitive testing findings and expert input led to the refinement and potential improvement of selected questions for inclusion in a national nutrition survey. Changes included simplified terminology, clearer instructions, improved examples, and better question order. Our methodological approach and findings may be valuable for those designing similar questions for dietary surveys.Item Data-driven progress prediction in construction: a multi-project portfolio management approach(Frontiers Media S A, 2025-12-16) Tagharobi M; Babaeian Jelodar M; Susnjak T; Mahdiyar AIntroduction: Construction projects often experience delays and cost overruns, particularly in regions like New Zealand, where natural hazards and climate change exacerbate these risks. Despite extensive research on forecasting overall construction timelines, limited attention has been given to stage-wise progress across the project lifecycle, constraining project managers’ ability to monitor performance and respond to risks. Methods: To address this gap, the study develops a stage-based forecasting model using Multinomial Logistic Regression, which was identified as the most suitable method after comparison with selected machine learning approaches within the study’s scope and assumptions. A stepwise comparative framework was employed to assess combinations of duration, value, type, and contractor involvement, measuring accuracy, log-loss, and Cohen’s kappa using 10 years of New Zealand construction data. Model reliability was further examined using confusion matrices to derive sensitivity, specificity, predictive values, and balanced accuracy. Validation was conducted through cross-validation, ROC/AUC, and temporal hold-out testing. Results: The results show that while all models performed reasonably well, the model using only project duration and value achieved the highest accuracy. The validation procedures confirmed the framework’s robustness and generalisability. Visualisations further illustrated milestone-specific progress predictions (5%–100%), making stage-wise forecasts easy to interpret. Discussion: The model provides project managers with practical insights for planning, monitoring, risk management, and resource allocation. By offering a transparent and interpretable approach, it bridges statistical forecasting with real-world practice, supporting timely delivery and data-driven infrastructure development. Future research could incorporate additional factors, extend the model locally and internationally, and explore integration with digital twins or real-time adaptive systems.Item Organ and tissue accumulation of titanium dioxide after acute, subacute, subchronic, and chronic oral exposure in mice and rats: a systematic review(BioMed Central Ltd, 2026-12-01) Mohammadparast V; Khan J; Truman P; Kim ND; Kruger MC; Bromhead C; Mallard BLBackground Titanium dioxide (TiO2) is a compound that is often used as a white pigment. Commercial TiO2, such as the food additive E171, contains a mix of particle sizes, including a fraction in the nanoscale range (< 100 nm). It is an ingredient in everyday products such as toothpaste, dietary supplements, and pharmaceuticals. Although the oral and gastrointestinal (GIT) tracts are the initial sites of exposure, in vivo studies have shown that TiO2 can cross the intestinal epithelium, enter systemic circulation, and accumulate in vital organs, where elimination is slow. This accumulation has been associated with oxidative stress, inflammation, cytotoxicity, and altered cellular function. Main body This systematic review assesses titanium (Ti) accumulation in vital organs of rats and mice following oral TiO2 exposure, focusing on dose- and time-dependent patterns across acute, subacute, subchronic, and chronic durations. Following PRISMA guidelines, 3,012 records were identified and screened by title and abstract, with 54 studies meeting predefined inclusion criteria. The findings reveal that acute oral exposure to TiO2 consistently results in minimal titanium accumulation across all major organs, indicating limited gastrointestinal absorption and rapid excretion. In contrast, subacute and subchronic exposures lead to significant, dose-dependent titanium accumulation, especially in the liver, spleen, kidneys, gastrointestinal tract, and brain. Chronic exposure studies, though fewer, indicate persistent Ti presence, especially in the liver, kidneys, and colon. Ti was also found in the brain, pancreas, and reproductive tissues, with histopathological changes indicating broader systemic effects. A few studies reported negligible accumulation even at high doses. Conclusion This review highlights the organ-specific and exposure-dependent biodistribution of titanium following oral TiO2 intake in rodents. The evidence emphasizes the need for standardized reporting and experimental methodologies to improve data comparability across studies. Importantly, it underscores significant gaps in our understanding of chronic and low-dose exposures, conditions more reflective of real-world human scenarios, warranting further investigation to better assess long-term health risks.Item Perspectives on pasture establishment in New Zealand dairy systems: challenges, innovations, and agroecological implications(Frontiers Media S A, 2025-12-05) Cartmill AD; Rivero MJ; Cartmill DL; Donaghy DJ; Ye LThe productivity and persistence of pasture species in Aotearoa New Zealand (NZ) are crucial for pastoral systems including the dairy, sheep, and beef industries and are predominantly based on perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.). Increasingly, farmers are exploring other simple grass/legume mixtures and also incorporating mixed species swards. This perspective paper critically examines the methods and challenges associated with pasture establishment, focusing on seed germination, sowing techniques, and post-establishment management. It discusses the influence of environmental factors including soil type, moisture, and temperature on seed germination and seedling persistence, alongside the impact of grazing practices on pasture longevity. Economic considerations and environmental impacts of various establishment methods, including overgrazing, chemical termination, and direct drilling, are examined. This perspective paper also covers the integration of new technologies such as precision agriculture, robotics, and advanced seed genetics, noting barriers to their adoption. From an agroecological perspective, we argue for a systems-based approach that integrates biodiversity, farmer knowledge, and long-term resilience into pasture renewal strategies. We also identify research gaps related to species persistence, climate adaptation, and policy support, and call for collaborative innovation to ensure the future productivity and ecological integrity of NZ pastoral system. Lastly, the paper highlights the need for further research into long-term pasture performance, species persistence, and the effectiveness of emerging technologies to optimise pasture management in NZ changing climate.
