Search Results (906)

Accurate body weight monitoring is essential for efficient sheep production, yet conventional weighing methods are labor-intensive and require frequent animal handling. Computer vision provides a promising non-invasive alternative; however, many published studies rely on validation strategies that may overestimate predictive performance because repeated observations from the same animals are simultaneously included in training and testing datasets. This study developed and evaluated an integrated analytical framework for image-based body weight estimation in ewes that combines standardized image processing, robust frame-level quality control, longitudinal statistical modeling, and strict leakage-controlled validation. A longitudinal dataset comprising 20 Dorper ewes monitored over six sampling periods was acquired using top-view depth imaging synchronized with body weight measurements under semi-arid conditions. The analytical framework integrated three complementary modules: longitudinal mixed-effects modeling, early prediction of final body weight, and contemporaneous body weight estimation. Predictive analyses were evaluated using nested leave-one-animal-out cross-validation, in which all preprocessing, correlation filtering, feature selection, model optimization, and model selection were performed exclusively within the training animals of each outer fold. The longitudinal mixed-effects model accurately characterized individual growth trajectories (conditional R² = 0.98). Initial body weight remained the strongest predictor of final body weight (R² = 0.770), whereas image-derived morphometric descriptors alone showed limited predictive performance under strict animal-level validation (R² = −0.899 to −0.031). Combining baseline body weight with selected morphometric descriptors produced modest but biologically informative improvements, achieving a maximum R² of 0.839. Contemporaneous body weight estimation achieved moderate predictive performance (maximum R² = 0.332) and revealed temporal changes in the importance of morphometric descriptors throughout growth. Overall, the proposed framework provides a reproducible methodology for evaluating image-derived phenotypes under rigorous animal-level validation, contributing to the development of more robust, interpretable, and biologically grounded computer vision systems for Precision Livestock Farming. Full article

Nitrites and nitrates are admitted into the body through the consumption of various foods, primarily cured meat products. These nitrites and nitrates are precursors of reactive nitrogen species NO and NO₂, which, in excess, promote nitrosative stress. Attempts have been made to combat oxidative and nitrosative stress through C₆₀ fullerenols in animal models. Furthermore, experimental and theoretical studies have shown that the use of carbon nanomaterials such as defective or doped graphene and C₆₀ metallofullerenes facilitates the capture of NO_x pollutants contained in the air. This leads us to propose that the inclusion of metals in C₆₀ fullerenols may have the potential to capture these reactive nitrogen species and be considered in nitrosative stress tests in animal models. Alternatively, viewed from another perspective, a certain grade of hydroxylation of metallofullerenes could enhance the capture of atmospheric nitrogen pollutants. Therefore, Li, Ca and Y metals were included in C₆₀ fullerenols at different coating grades. Using density functional theory (DFT), we analyzed the antiradical character of these metallofullerenols, and the adsorption energies of the free radicals (NO_x) were calculated to evaluate the ability of these metallofullerenols to adsorb these nitrogen species. Although both fullerenols and endohedral metallofullerenes have individually shown promise as radical scavengers, a systematic understanding of how the encapsulated metal and the grade of hydroxylation jointly govern the capture of nitrogen species is still lacking. In particular, it remains unclear whether increasing the number of hydroxyl groups monotonically enhances the capture capacity or whether optimal combinations of metal identity and surface functionalization exist. Addressing this gap is crucial, since excessive hydroxylation may alter the electronic structure, stability, and mechanism of interaction with NO_x radicals, potentially compromising capture capacity. Therefore, a rational evaluation that simultaneously considers electronic donor–acceptor properties, local reactivity, and adsorption thermodynamics is required to identify metallofullerenols with possible potential to sense or scavenge NO_x. Full article

Forecasting individual cattle live weight in herd-managed grazing systems remains challenging because automated weighing observations are irregular and environmental conditions vary seasonally. Evidence remains limited for live-weight forecasting across multiple forecasting periods under commercial grazing conditions. This study developed a machine learning (ML) framework for forecasting the live weight of individual cattle using automated observations from a managed herd. The framework incorporated demographic variables, historical live weights, and climatic lag predictors. The framework compared monthly, weekly, and rolling-window aggregations across forecasting periods of 1, 2, and 3 months. Quality control retained 494 of 1140 cattle (43.3%), yielding 4069 monthly aggregated records. The resulting dataset was more suitable for modelling cattle with regular voluntary weighing records. The respective forecasting datasets contained 3048, 2558, and 2068 records for one-, two-, and three-month periods. Gradient Boosting achieved the strongest testing performance. The corresponding coefficients of determination (R²) were 0.950, 0.935, and 0.902. Monthly aggregation achieved higher entropy retention, greater variance preservation, and stronger forecasting performance than alternative aggregation approaches. Feature-importance analysis identified animal age and historical live weight as the most important predictors across all forecasting periods. Lagged rainfall and temperature variables provided complementary predictive information for medium-term forecasting. The findings demonstrate that automated livestock monitoring, climatic information, and ML can support accurate live-weight forecasting. The framework produced forecasts across multiple periods for individual cattle in herd-managed grazing systems. Full article

Background: Veterinary autogenous vaccines (AVs) are emergency tools produced in a short timeframe from bacterial/viral/fungal isolates when commercial vaccines are not available and undergo strict quality assurance and safety tests before release. In accordance with the European Directive 2010/63/EU and the 3R principles, we evaluated for the first time the possible substitution of the final toxicity in vivo test (abnormal toxicity test) with an alternative cell-based and embryo-based assay. Methods: The five most requested different autogenous matrices (adopted to produce a customizable number of lots requested from customers) were tested in vitro in parallel for residual toxicity by in vitro fish embryo acute toxicity (FET) test and cytotoxicity assay (MTS) using serial dilutions, together with the authorized in vivo test. Results: Statistical analysis revealed different outcomes between the two in vitro methods, highlighting the greater discriminatory power of the MTS assay compared to the other, with results more like the observed in vivo ATT outcome (pass/negative). Conclusions: In this preliminary first dataset, FET appeared poorly compatible with several complex autogenous vaccine matrices, while the L929 MTS assay yielded interpretable viability thresholds for all tested matrices. These findings support further qualification of MTS as part of an integrated non-animal batch characterization strategy, but they do not yet establish replacement of the in vivo test for veterinary autogenous vaccine quality control. Full article

Salmonella Typhimurium is an important pathogen affecting both animal production and public health, with pigs representing a major reservoir. The increasing prevalence of antimicrobial resistance highlights the need for alternative or complementary therapeutic strategies. Carvacrol, a phenolic constituent of Origanum vulgare essential oil, has recognized antimicrobial activity and may contribute to the modulation of antimicrobial resistance mechanisms. The present study investigated the antimicrobial activity of carvacrol and tetracycline, individually and in combination, against swine-derived multidrug-resistant Salmonella Typhimurium strains. Minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) were determined by broth microdilution. Interactions between both compounds were assessed by checkerboard assays using the fractional inhibitory concentration index (FICI). In addition, the modulatory effect of carvacrol on the expression of the tetracycline resistance genes tetA and tetB was evaluated to provide preliminary insight into the molecular basis of these interactions. Relative expression of tetracycline resistance genes was analysed by quantitative real-time PCR in selected isolates exposed to tetracycline alone or combined with carvacrol. Carvacrol MIC values ranged from 0.5 to 16 mg/mL, with MIC₅₀ and MIC₉₀ values of 2 and 4 mg/mL, respectively. MBC and MIC values were identical in 84.9% of the isolates, indicating a strong bactericidal effect. Tetracycline MIC₅₀ and MIC₉₀ values were 256 and 512 µg/mL, respectively. Checkerboard assays showed synergistic interactions in 14.3% of strains, additive effects in 50.0%, indifferent responses in 28.6%, and antagonism in 7.1%. Combined exposure reduced tetA and tetB expression in most tested isolates compared with tetracycline alone, although responses were strain-dependent. These findings demonstrate that carvacrol exhibits antimicrobial activity against swine-derived multidrug-resistant Salmonella Typhimurium and may enhance tetracycline activity in a subset of isolates under the experimental conditions evaluated, while modulating resistance-associated gene expression. These findings provide a basis for future transcriptomic and proteomic studies aimed at further elucidating the molecular mechanisms underlying the interaction between carvacrol and tetracycline. Full article

Background/Objectives: Alzheimer’s disease (AD) is associated with progressive hippocampal circuit dysfunction, but electrophysiological measures of state-dependent abnormalities and treatment responsiveness remain incompletely characterized. We examined hippocampal theta–gamma coupling in 5xFAD mice across behavioral states and after donepezil. Methods: Local field potentials were recorded from CA1 in freely behaving wild-type (WT) and 5xFAD mice during home-cage activity, open-field exploration, and Y-maze testing. Power spectral density and theta–gamma phase–amplitude coupling (PAC) were quantified at the animal level at baseline and after seven days of donepezil. Results: Untreated 5xFAD mice showed reduced theta–low-gamma coupling during home-cage and open-field activity, but not Y-maze exploration, and elevated theta–high-gamma coupling in all three contexts. Donepezil increased theta–low-gamma coupling during open-field and Y-maze exploration and produced a partial numerical shift toward WT levels in the home cage. For theta–high-gamma coupling, the treated group did not differ significantly from either comparator. Untreated 5xFAD mice also showed reduced center exploration and distance traveled in the open field, while Y-maze spontaneous alternation was unchanged. Theta–high-gamma coupling correlated positively with open-field center time in WT mice only. Conclusions: Hippocampal theta–gamma coupling shows frequency- and context-dependent abnormalities in 5xFAD mice. Theta–low-gamma coupling is sensitive to short-term cholinergic modulation during exploration, whereas donepezil’s effect on theta–high-gamma coupling remains inconclusive. Animal-level PAC may provide a candidate functional readout, but longitudinal and cross-model validation is required before biomarker claims are justified. Full article

Background: Bacillus clausii SKB/BCL21 (MCC 0569) is a novel strain that shows promise as a probiotic for both human and animal healthcare. Objectives: The objective is to evaluate the safety profile of B. clausii SKB/BCL21 through genomic and toxicity assessments in Wistar rats, as well as to assess its efficacy as a probiotic in broiler chickens challenged with Clostridium perfringens. Methods: The identification of genus and species was performed using 16S rRNA and whole genome sequencing (WGS). A genomic analysis was conducted through bioinformatic screening of the B. clausii SKB/BCL21 genome to identify virulence factors, genes encoding toxins, mobile genetic elements, and antibiotic resistance genes. In vitro biosafety assays were conducted to evaluate mucin degradation, gelatinase, hemolytic activity, and DNase activity. The in vivo safety evaluation was performed by acute and subacute oral toxicity studies as per the OECD 423 guidelines. In efficacy testing broilers challenged with C. perfringens were administered with low dose (1 × 10⁸ cfu/kg of feed) and high dose (1 × 10⁹ cfu/kg of feed) of B. clausii SKB/BCL21. Performance metrics, such as average weight gain, feed conversion ratio (FCR), and mortality rates, were evaluated in comparison to a positive control group that received Virginiamycin 50% (15 ppm). Results: The isolate SKB/BCL21 was identified as Bacillus clausii based on 16S rRNA and whole genome sequencing (WGS). The bioinformatic analysis of the B. clausii SKB/BCL21 genome reveals that it lacks genes associated with toxins, mobile genetic elements, and virulence factors. However, it does contain intrinsic and non-transferable antibiotic resistance genes within its chromosomal DNA. In the acute toxicity study, an oral dose of 2000 mg/kg (400 billion cfu/kg) body weight was found to be nontoxic. The No Observed Adverse Effect Level (NOAEL) for B. clausii SKB/BCL21 was found to be 1000 mg/kg (200 billion cfu) body weight/day by oral route in the subacute toxicity study. The findings of in vivo toxicity studies indicate that there were no treatment-related changes in any of the endpoints assessed. The effects of low (1 × 10⁸ cfu/kg of feed) and high (1 × 10⁹ cfu/kg of feed) doses of B. clausii SKB/BCL21 on the growth performance metrics, including average weight gain, feed conversion ratio, and mortality rates in broiler chickens infected with C. perfringens, showed results similar to those of the positive control (Virginiamycin 50%, 15 ppm). Conclusions: Based on these preliminary studies, B. clausii SKB/BCL21 can serve as a potential alternative to antibiotic growth promotors in broiler production. These results suggest that the B. clausii SKB/BCL21 is safe and could be a potential probiotic for animal feed supplements. Full article

Brazilian hydropower plants have been facing increasing challenges during periods of hydrological instability associated with climate change, making adaptation imperative. One promising approach to achieving adaptation is to learn from nature, given its inherent capacity for adaptability and resilience to environmental change. Accordingly, this study proposes an integrated framework that combines Animal Decision-Making (ADM) theory with a successful example of natural adaptation, namely Amazon rainforest ant colonies. The proposed methodology comprises the following stages: (1) identification; (2) definition; (3) alternative generation; (4) solution selection; and (5) implementation and testing. A simulated case study and a real-world case study involving the Ponte de Pedra Hydropower Plant, located in the state of Mato Grosso, Brazil, were investigated. Human operators and ant colonies exhibited similar probabilities of shifting towards adaptation (human operators, p_R = 0.7088; ant colonies, p_R = 0.7091). However, the adaptation strategy adopted by the ant colonies proved to be more focused, concentrating on a smaller number of performance areas. Human operators identified Operation and Maintenance (O&M), Finance, and Plant as the most affected performance areas, with similar levels of importance (12%, 11%, and 11%, respectively). In contrast, the ant colonies prioritised O&M, Plant, and Environmental Impact, with corresponding importance levels of 18%, 13%, and 10%, respectively. Furthermore, the ant colonies demonstrated a dynamic and integrated decision-making strategy that prioritised different activities according to local environmental conditions. Future research should focus on evaluating, calibrating, and validating the proposed framework using historical data. Full article

Background: Adenoviral vectors are widely used in vaccine development; however, pre-existing immunity to common human adenovirus serotypes can limit their effectiveness. Canine adenovirus type 2 (CAV-2) is a non-human adenovirus with low seroprevalence in humans, making it a suitable alternative vector. Despite its promise, comprehensive preclinical safety data for CAV-2 vector-based vaccine platforms remain limited. In this study, we evaluated the safety profile of a replication-defective CAV-2 vector expressing the Omicron BA.4 SARS-CoV-2 spike immunogen in BALB/c mouse models. Methods: The SARS-CoV-2 CAV-2 vector-based vaccine was expressed and propagated in AD293 cells. The mice received intramuscular prime-boost immunisations with low (1 × 10⁶ PFU), moderate (0.5 × 10¹⁰ PFU), or high (1 × 10¹⁰ PFU) vaccine doses, alongside empty CAV-2 vector and physiological buffer control groups, and were monitored longitudinally up to Day 72. The mice were clinically assessed at days 0, 7, 21, 42, and 72 for any deviations from normal conditions in comparison to the control groups. Biochemical analyses were performed to evaluate liver and kidney function, as well as any tissue injury due to the vaccine candidate. Hematological parameters were assessed by conducting complete blood counts. Body temperature and weight changes were also monitored as an indicator of systemic toxicity. Results: The biochemical and haematological parameters remained within physiological reference ranges across all dose groups and timepoints, with no dose-related deviations, indicating that the vaccine candidate did not show evidence of hepatotoxicity, nephrotoxicity, tissue or haematological toxicity. Body temperatures remained within normal physiological ranges following both prime and booster immunisations, and body weights increased normally across all groups as the animals grew throughout the study period without any abnormal weight gain or loss. Conclusions: These results suggest that the replication-defective CAV-2-vectored SARS-CoV-2 vaccine candidate was well tolerated and did not demonstrate evidence of systemic toxicity under the conditions tested. These findings demonstrate that the CAV-2 vector exhibits a favourable safety profile in murine models when used as a vaccine delivery platform, supporting its translational potential as an alternative adenoviral vector-based vaccine platform. Further studies incorporating additional safety endpoints, including histopathological, vector persistence and shedding evaluation, are warranted to support continued development of the platform. Full article

The development of next-generation organotypic platforms and disease models has proven crucial for the progress toward personalized therapeutic solutions in cancer. Fetal bovine serum (FBS) is a nutrient-rich cell culture supplement that contains essential factors for cell growth. However, in addition to ethical and environmental concerns, the manufacturing of tumor models requires a more standardized and controlled environment. This has led to the commercialization of several alternatives for the substitution of FBS, in the form of both animal-based and synthetic products. We here test the use of two alternatives for the culture of glioblastoma cells in the fabrication of organotypic tumor models, in combination with an insightful review of the existing literature, which allows for the elucidation of the most relevant challenges and potential solutions. We assess metabolic activity and cell proliferation in both 2D and 3D culture systems to determine the influence of serum on cell attachment and growth. The 3D culture systems are fabricated by photopolymerization of gelatin methacrylamide to achieve hydrogels that closely mimic the native tissue’s extracellular environment. We aim to advance our understanding of the role of culture media in these models and provide practical guidance to optimize experimental design and enhance reproducibility, thereby facilitating their broader adoption by the research community. These studies are key for the biofabrication of next-generation organoids and other advanced in vitro tumor models. Full article

Background/Objectives: Rabies remains a lethal vaccine-preventable disease in India, and physicians managing animal-bite cases are central to effective post-exposure prophylaxis (PEP). With the increasing use of rabies monoclonal antibodies (RmAbs) as alternatives to conventional rabies immunoglobulins, this study assessed physicians’ knowledge, attitude, and practice (KAP) regarding rabies PEP, including RmAb awareness and acceptance. Methods: This multi-state, cross-sectional retrospective KAP survey was conducted among 208 physicians across ten Indian states using a structured, self-administered Google Form. The 33-item questionnaire assessed Knowledge, Attitude, and Practice domains, with 11 items each, scored binarily according to NCDC guidelines. Descriptive statistics, Shapiro–Wilk normality testing, Kruskal–Wallis tests with post hoc corrections, and Spearman rank-order correlations were performed. Results: Mean domain scores were 8.00/11 for Knowledge (72.7%), 7.22/11 for Attitude (65.6%), and 8.64/11 for Practice (78.5%). Key gaps were identified in the intramuscular pre-exposure prophylaxis schedule, management of excess RIG/RmAb after wound infiltration, exposure categorization of animal contact, and vaccine administration site in young children. The Knowledge–Practice correlation was moderately strong and statistically significant (r = 0.520, p < 0.001). Acceptance of RmAbs was high, with 88.5% recognizing them as effective replacements for RIGs and 84.6% considering them safer than RIGs. Practice scores showed the most consistent improvement, Knowledge scores improved on most items but declined sharply for the pre-exposure prophylaxis schedule, and Attitude scores showed a mixed pattern of gains and losses compared with the 2013 benchmark survey. Conclusions: Overall KAP scores were adequate, with Practice scoring highest. Targeted continuing medical education focused on NCDC guidelines and practical PEP scenarios is needed among physicians managing rabies exposures. Full article

Foot-and-mouth disease (FMD) represents one of the most severe transboundary animal diseases globally. Although considered endemic in Ghana, recent data on circulating serotypes are limited. This study investigated and characterized FMD outbreaks occurring between July and December 2024, assessed the occurrence of the infection in seemingly healthy cattle imports, and explored alternative methods to enhance early diagnosis in livestock; using probang Sera, epithelial tissue and oral mucosal swabs were obtained from cattle exhibiting signs suggestive of FMD from farms, livestock markets and a slaughter facility. This was followed by a cross-sectional survey at two major points of entry (POE) to Ghana to obtain oropharyngeal samples using probang from healthy cattle to assess the possible role of imported cattle in the outbreaks in the northern and southern regions of the country. Samples were analysed for FMD virus (FMDV) and non-structural protein (NSP) antibodies to assess infection and exposure from the outbreak foci and POE. Positive samples were sequenced to characterize the virus serotypes. Outbreaks were reported in 38 kraals, three livestock markets, and one slaughter facility across 14 districts in nine regions. Morbidity rates ranged from 8% to 100% (median = 50%), with fatalities occurring in three kraals. Of the 247 samples from outbreak locations, FMD virus was detected in 49.4% (122/247). A majority of cattle (66.03%, 140/212) tested seropositive for FMD NSP antibodies. From healthy cattle at POE, 250 oropharyngeal (probang) samples were collected, with 62.4% testing positive, distributed between the north and south. Only 1.6% of the samples had FMDV RNA detected using PCR. Phylogenetic analysis identified serotypes O, A, and SAT2. These findings confirm the co-circulation of multiple FMDV serotypes in Ghana and highlight the necessity for enhanced molecular surveillance and coordinated cross-border control measures. Full article

The increasing prohibition of animal testing for cosmetic products has driven the development of alternative approaches to ensure consumer safety. Skin sensitization is one of the most critical toxicological endpoints to evaluate, requiring rigorous assessment to ensure the safety of cosmetic ingredients. This study proposes an Integrated Testing Strategy (ITS) that combines in chemico (Direct Peptide Reactivity Assay—DPRA) and in silico approaches (a six-platform computational panel) to evaluate the sensitization potential of substances. Initially, the in chemico methodology was validated through a partial proficiency demonstration to ensure experimental reliability. Subsequently, this ITS was applied to the Baccharis trimera extract and its major marker, 3-Caffeoylquinic acid (chlorogenic acid/3-CQA). Our results demonstrate that the DPRA alone is insufficient to classify the sensitization potential of complex mixtures, as recommended by OECD guidelines. The integration of in silico data proved essential to interpret the reactivity of the botanical matrix, revealing that the sensitization potential observed in the extract does not stem solely from 3-CQA, but likely results from the synergistic contribution of more lipophilic caffeoylquinic acid isomers. This approach demonstrates that integrating experimental and computational methods is fundamental for a robust safety assessment, offering an efficient, animal-free strategy for the early screening of cosmetic ingredients and for refining the interpretation of toxicological data in complex chemical environments. Full article

The escalating global concern regarding bacterial antibiotic resistance in animal production has intensified the search for sustainable and effective alternatives to conventional antimicrobials. In this study, two L. reuteri strains (LBM-Ti195 and LBM-Ti173) are isolated from broiler cecal microbiota that were characterized through an integrated approach, combining phenotypic assays with comparative genomic analysis. Both strains exhibited antibacterial activity against relevant veterinary and foodborne pathogens, including Listeria monocytogenes CECT 934, Staphylococcus aureus CECT 239, Clostridium perfringens Type A, and Campylobacter jejuni CCAMP 162. The inhibitory activity anti-S. aureus increased by more than 10% modifying cultivation conditions, while comparative genomic analysis identified an M23-family metallopeptidase as a potential candidate for pathogen inhibition. Phenotypically, both strains produced folate and metabolized fructooligosaccharides (FOS) and inulin, supporting their potential compatibility with synbiotic formulations. Genome reconstruction reinforces these functional findings by revealing a complete predicted de novo folate biosynthesis pathway. In addition, CAZyme annotation identified higher copy numbers of glycosyltransferases GT2 and GT4 compared with the reference strains, suggesting differences in cell-surface carbohydrate metabolism and exopolysaccharide (EPS)-associated traits. Safety profiling revealed no hemolytic activity or conserved virulence factors under the tested conditions. However, phenotypic tetracycline resistance was detected, and in silico analysis identified an acquired tetW gene in a putative plasmid-associated context, highlighting the importance of an in-depth evaluation of strains with probiotic potential. Collectively, these findings position LBM-Ti195 and LBM-Ti173 as promising avian-derived L. reuteri candidates for next-generation zootechnical probiotic development, while highlighting antimicrobial resistance (AMR) mitigation and further functional validation as essential steps toward safe application. Full article

Staphylococcus aureus is a major bacterial pathogen that can cause clinical infections and foodborne illnesses through the production of 25 exotoxin types. The most frequently implicated toxins in food poisoning outbreaks are Staphylococcal enterotoxins type A–E (SEA-SEE), which are the first enterotoxins discovered. While in vitro detection methods are available to identify the presence of enterotoxins, they cannot distinguish between biologically active and inactive forms of the toxins. Detection of biologically active enterotoxins currently relies on in vivo testing, using the emetic response in kittens or monkeys. Here, we show the development of an in vitro assay to detect the active forms of SEB, a potential biological warfare agent and leading cause of food poisoning, and SEC1, a frequent cause of staphylococcal food poisoning. The novel assay involves the implementation of a genetically engineered Jurkat T-cell line expressing TCR Vβ3, resulting in a dose response of IL-2 production when exposed to active toxin. We also show that at a concentration of 100 ng/mL, the biological activity of SEB is significantly decreased at temperatures over 70 °C, while pasteurization at 63 °C only slightly reduces the biological activity of the toxin. Our studies provide an alternative method to animal testing to determine the presence of active toxins and provide possible inactivation methods of the toxins. Full article