Phaidra - University of Veterinary Medicine Vienna
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Behavioural responses of brown bears to helicopter capture
No full textUnderstanding the effects of capture and handling on wild animals is crucial in evaluating ethical practices in ecological research, and in avoiding biased conclusions from misinterpreting biologging data potentially affected by capture. The aim of this study was to assess the effects of helicopter capture on the behaviour of Scandinavian brown bears by comparing the expression of specific behavioural states between captured bears in spring and bears of a control group that were not captured during the same time period. We identified three different behavioural states: stationary, walking/foraging and transit. Our study revealed that captured bears were more stationary for up to four days after capture compared to bears of the control group, depending on their reproductive state. We found higher doses of the immobilizing drug, as well as abdominal surgery, to negatively impact the bears\u27 movement after capture, highlighting the importance of careful consideration of drug doses and invasive procedures during wildlife capture. This study advances our understanding of the impact of helicopter capture and surgery on the movement of brown bears and helps to refine capture and handling protocols to ensure well-being and welfare during wildlife capture
Autophosphorylation of conserved yeast and human casein kinase 1 isozymes regulates Elongator-dependent tRNA modifications
No full textCasein kinase 1 (CK1) family members are crucial for ER-Golgi trafficking, calcium signalling, DNA repair, transfer RNA (tRNA) modifications, and circadian rhythmicity. Whether and how substrate interactions and kinase autophosphorylation contribute to CK1 plasticity remains largely unknown. Here, we undertake a comprehensive phylogenetic, cellular, and molecular characterization of budding yeast CK1 Hrr25 and identify human CK1 epsilon (CK1ϵ) as its ortholog. We analyse the effect of Hrr25 depletion and catalytically inactive mutants in vivo and show that perturbations in CK1 activity lead to stress-induced growth defects, morphological abnormalities, and loss of Elongator-dependent tRNA modification. We use purified Hrr25 protein to identify distinct autophosphorylation patterns and phospho-sites on several physiological substrates in vitro and find only human isozyme CK1ϵ can replace yeast Hrr25 functions essential for tRNA modification and cell proliferation in vivo. Furthermore, we demonstrate that human and yeast CK1 orthologs share conserved autophosphorylation sites within the kinase domains, which regulate their activities and mutually exclusive interactions with Elongator subunit Elp1 and Sit4, a phosphatase antagonist of Hrr25. Thus, autophosphorylation controls CK1 activity and regulates the tRNA modification pathway. Our data offer mechanistic insights into regulatory roles of CK1 that are conserved between yeast and human cells and reveal a complex phosphorylation network behind CK1 plasticity
AI for One Welfare: the role of animal welfare scientists in developing valid and ethical AI-based welfare assessment tools
No full textThe increasing use of artificial intelligence (AI) in livestock farming is accelerating the development of automated welfare assessment tools, particularly with advancement in generative AI such as large multimodal models (LMMs). Yet, animal welfare scientists have rarely been involved in the development process of these tools or their subsequent adaptation within the field. Here, we discuss possible roles for animal welfare scientists in the development and validation of AI-based welfare assessment tools. We first examine key uncertainties that emerge during development, including the selection of relevant, valid and reliable welfare indicators and gold standards, hardware and software solutions for data collection, methods for integrating multiple welfare indicators, and the real-world impact of automated welfare assessment tools. Second, we demonstrate the use of LMMs to assess welfare based on a case study using dairy cow cleanliness. Finally, we consider the practical implementation of AI-based welfare assessment and discuss potential tensions around (1) embedded values in LMMs, (2) AI’s influence on decision-making on farms, (3) the integration of AI in current knowledge systems by human-AI collaboration, and (4) the economics of AI-based welfare assessment and improvement. We conclude that LMMs could help automate welfare assessment and communicate results to humans in accessible formats, but outcomes depend on which stakeholders are involved in the development process. We advocate for developing AI-based welfare assessment tools through the One Welfare framework, recognizing that AI deployment affects humans, animals, and the environment simultaneously, and suggest potential pathways for animal welfare scientists to engage in the process
Accurate identification of bovine deltapapillomavirus in equine sarcoids by ddPCR
No full textSarcoids are benign and locally aggressive skin lesions that commonly affect horses and other equid species. Sarcoids are generally considered to be caused by bovine delta-papillomaviruses (delta PVs) types 1 and 2 (BPV1 and BPV2, respectively). Moreover, while bovine delta PV types 13 and 14 (BPV13 and BPV14, respectively) are also suspected to induce sarcoids, information regarding this possibility and the occurrence of multiple bovine delta PV infections in sarcoids is scarce. This study aimed, for the first time, to assess BPV1, BPV2, BPV13, and BPV14 infections and co-infections in equine sarcoid samples of Austrian provenance, and to determine the intralesional DNA loads of the detected bovine delta PV types using highly sensitive droplet digital polymerase chain reaction (ddPCR). BPV DNA was detected in 93 sarcoid samples. The analyses revealed that BPV1 was the predominant bovine delta PV type in sarcoids from Austria, with 83/93 lesions testing BPV1-positive. Importantly, 66 tumors also contained BPV2 DNA. In six cases, a triple infection including BPV13 or BPV14 was noted, and one lesion showed a quadruple infection. This is the first ddPCR-based study to show multiple infections by all four bovine delta PVs in equine sarcoids. Clinical data suggest that BPV1/2 co-infection may be associated with more severe and therapy-resistant disease. In-depth studies are required to investigate this possibility in greater detail
Using Faecal Cortisol Metabolites to Assess Adrenocortical Activity in Wild-Living Alpine Marmot Marmota marmota: A Biological Validation Experiment
No full textFaecal cortisol/corticosterone metabolites (FCMs) have become increasingly popular as an easy-to-sample, non-invasive and feedback-free alternative to assess glucocorticoid (GC) levels, key components of the neuroendocrine stress response and other physiological processes. While FCMs can be a powerful aid, for instance, for gaining insights into ecological and evolutionary processes, as well as to assess animal welfare or impacts of anthropogenic stressors on wildlife populations, this method comes with specific challenges. Because GCs are heavily metabolised before excretion, it is critical to validate the enzyme immunoassays (EIAs) used to measure FCMs. Additionally, because species may differ in metabolite profiles, assay validation must be performed separately for each focal species. Despite this, the use of unvalidated assays remains widespread. We performed a biological validation experiment to test a set of EIAs to measure FCMs and adrenocortical activity in free-living Alpine marmots Marmot marmota. We capitalised on capture and handling as part of a relocation project of marmots under the assumption that capture, and handling represent a stressful event and tracked changes in FCM levels over the following 48 h. Faeces samples collected at capture were assumed to return baseline FCM levels. Of the three EIAs tested, only the 11-oxoetiocholanolone ‘72T’ EIA detected an increase in FCM levels about 18 h after capture. This result paves the way for future studies using FCMs to investigate the adrenocortical activity in this species
A consensus on the definition of positive animal welfare
No full textThe concept of animal welfare is evolving due to progress in our scientific understanding of animal biology and changing societal expectations. Animal welfare science has been primarily concerned with minimizing suffering, but there is growing interest in also promoting positive experiences, grouped under the term positive animal welfare (PAW). However, there are discrepancies in the use of the term PAW. An interdisciplinary group arrived at a consensus that \u27PAW can be defined as the animal flourishing through the experience of predominantly positive mental states and the development of competence and resilience. PAW goes beyond ensuring good physical health and the prevention and alleviation of suffering. It encompasses animals experiencing positive mental states resulting from rewarding experiences, including having choices and opportunities to actively pursue goals and achieve desired outcomes\u27. The definition also considers individual and species-specific differences. It provides a framework for researchers to investigate PAW and thereby generate innovative, informative and reproducible science. Studies of PAW can contribute to a richer picture of an animal\u27s life and may elucidate the biological foundations of happiness. The definition creates opportunities to inspire scientific progress in animal biology and to align animal care practices, legislation and markets with societal expectations
Locus-specific chromatin proteomics using dCas-guided proximity labelling in aspergillus nidulans
No full textProximity labelling that uses promiscuous biotin ligases (BirA) fused to a bait protein is a powerful tool to identify protein interaction partners in vivo under different metabolic or developmental conditions. BirA can also be used to determine protein composition and interaction partners at specific chromatin locations when it is fused with enzymatically-disabled Cas9 (dCas9) and then guided to the location of interest by sgRNAs. We adapted this method (called CasID) for fungal cells using the nitrate assimilation gene cluster of A. nidulans as a model locus and estrogen-inducible expression of the dCas9-BirA fusion to improve condition-specific labelling. For method establishment, we first verified the presence of dCas-BirA and a known transcription factor at the nitrate locus by chromatin immunoprecipitation (ChIP). Results show that both dCas-BirA and the AreA transcription factor are present at the locus of interest under the conditions used for biotinylation. We then optimized the CasID procedure for efficient labelling and background reduction using the CasID-sgRNA strain and two control strains, one lacking the sgRNA and another one lacking the whole CasID system. Here we provide proof-of-concept for the suitability of the method by showing that biotinylated proteins are enriched in the CasID strains in comparison to the controls. After background reduction, 32 proteins remained in two independent experiments exclusively enriched in the Cas-ID-sgRNA strain. Among these proteins was NmrA, an AreA-interacting regulator, and we also found several chromatin-associated proteins. Overall, our results demonstrate that CasID is suitable for locus-specific labelling and identification of chromatin-associated proteins and transcription factors in A. nidulans. However, the high background of proteins that are biotinylated out of chromatin context or unspecifically attach to the affinity purification matrix needs to be addressed by implementing a set of rigorous controls. In summary, we herewith provide a detailed protocol for application of the method that proved to be useful for the identification of novel chromatin-associated proteins and their interaction partners at a specific genomic locus in divers metabolic and developmental conditions. AUTHOR SUMMARY: This study demonstrates that locus-specific proteomics can be carried out by dCas-BirA guided proximity labelling in Aspergillus nidulans. For establishment, we targeted the well-described bidirectional promoter region between niaD, a nitrate reductase, and niiA, a nitrite reductase. At this locus we could test by chromatin immunoprecipitation (ChIP) in combination with qPCR if both, the dCas9-BirA fusion as well as a central transcription factor are at the locus under the conditions of our CasID experiment. After this first control step, we considered that unspecific labelling by dCas-BirA during the time from translation to landing at the targeted chromatin locus may be one of the most relevant drawbacks of the method. Therefore, we developed a number of control strains that would allow us to clearly discriminate between background and sgRNA-dependent specific labelling at the locus. Our protein MS results validated these estimates and only considering the results of these controls enabled us to distinguish the set of locus-specific proteins from a very high general background. Finally, enrichment of biotinylated proteins through affinity purification with streptavidin resin and subsequent LC-MS/MS analysis showed that more than 800 proteins were detected in each sample, emphasizing the high background of the purification method. After background reduction of the control samples, we were able to identify 32 proteins which were exclusively detected in the test strain in two independent measurements, including several chromatin-associated proteins and NmrA, a negative regulator of the nitrate locus transcription factor AreA
Stimulus enhancement in kea, Nestor notabilis, in an object choice task
No full textPrevious studies illustrated that kea, Nestor notabilis, can apply socially acquired information to solve both simple and complex tasks. However, evidence of which social learning mechanisms kea utilize is still vague. Therefore, in this study, we investigated the role of stimulus versus local enhancement as mechanisms of social learning in an object choice task. We presented 10 kea individuals with objects of four different shapes and nine different colours and tested whether observer kea would copy the object and/or apparatus choice of two demonstrator kea, which were given free choice. This experimental setup significantly decreased training rotations for demonstrators and led to randomization across trials, thus presenting a promising new technique for future studies. Overall, observer kea chose the same objects more often than expected by chance, suggesting some evidence for stimulus enhancement as the primary social learning mechanism. Meanwhile, we find no evidence for local enhancement. These results are in line with kea behavioural ecology as an inquisitive island species that spends a lot of time gathering information about objects (i.e. stimuli). Additionally, highly fluctuating resource availability and depletion rates in their natural environment could make the information of locality less valuable to them. This study helps explain ambiguous results from past experiments and supports distinguishing the different processes at play in the social learning of kea. To understand the full picture of social learning in kea, less complex mechanisms, such as stimulus enhancement, will need to be tested and excluded in future experiments
Vetmed : das Magazin der Veterinärmedizinischen Universität Wien und der Gesellschaft der Freunde der Veterinärmedizinischen Universität Wien 1/2025
No full textDas Universitätsmagazin berichtet über die vielfältigen Aktivitäten der Universität in Forschung, Studium und Universitätskliniken, informiert über Tiergesundheit, Tierhaltung und Tierschutz sowie Lebensmittelsicherheit und beschäftigt sich mit Fragen der Mensch-Tier-Beziehung.Schwerpunkt der Ausgabe: Rektoratswechse
Cofeeding at rich clumped food patches in free-ranging dogs: social tolerance or scramble competition?
No full textAnimals are generally expected to monopolize food patches whenever possible. However, cofeeding within a defendable range occurs in many species, particularly at larger food patches, but the mechanism behind that remains underexplored. In theory, it could be due to multiple, mutually non-exclusive processes. First, larger food patches may saturate multiple top-ranking individuals, enabling cofeeding even under pure contest competition. Second, cofeeding may result from social tolerance where dominant individuals provide cofeeding concessions to certain subordinates. Third, cofeeding may result from prevailing scramble competition (i.e., indirect competition through patch exploitation) caused by large numbers of individuals that prevent monopolization ("swamping"). To investigate and differentiate between these mechanisms, we applied feeding tests to free-ranging dogs in Morocco. We provided them with a large food patch plus a varying number of small food patches. Although the small food patches were virtually always monopolized by single individuals, the dogs typically cofed in large and very dense feeding groups at the large food patches. Controlling for alternative explanations using multivariate statistics, we found that access to feeding groups was independently predicted by rank and social relationship strength, suggesting that contest competition and social tolerance play a role. However, aggression rates by
top-rankers decreased with increasing feeding group size, suggesting decreasing monopolizability and increasing scramble competition. Our results underscore that social tolerance may not reduce competition but shifts it from contest to scramble competition. This can be due to active levelling, licensing more individuals access to the resource, but also to loss of control caused by swamping.Although animals are generally expected to fight for resources, they are sometimes observed to cofeed peacefully in large groups. Such peaceful cofeeding is typically ascribed to and taken as a measure of social tolerance, assuming that dominants overcome their impulse to monopolize and make concessions to lower-ranking group members. Alternatively, such large peaceful cofeeding groups may result from swamping where lower-ranking group members overrun dominants as a mob. In this scenario, the dominant individuals simply lose control. Fighting would be pointless and only make them lose feeding time and reduce their share while others are feeding. Studying feedings of free-ranging dogs, we show that aggression by dominants decreases with increasing feeding group size, which supports this alternative explanation and sheds new light on the emergence of cofeeding and social tolerance.The online version contains supplementary material available at 10.1007/s00265-025-03590-8