Biology subjects

Riemer, S.

Publications and source records attributed to Riemer, S..

6 recordsLinked to original sources

bioRxiv2025

Automated Facial Landmark Analysis vs. Manual Coding: Accuracy in Dog Emotional Expression Classification

Emotional expression in dogs is central to dog-human interactions. Reliable indicators are essential for interpreting animal emotions; however, their predictive value remains debated. Fireworks, which elicit fear in many dogs, provide a real-world context for examining affective states. We used machine learning to classify firework vs. non-firework situations from dogs behaviour and expressions using two approaches: (1) ethogram-based manual coding of behaviours and (2) automated analysis of facial landmarks. The Random Forest model based on manual coding achieved a high accuracy (0.83) and 1.0 predictive validity, identifying backwards-directed ears and blinking as key fear indicators. The best automated facial landmark model reached up to 0.80 accuracy and 0.77 predictive validity. Manual coding performed better, likely due to richer semantic content and full-body observations. Our findings demonstrate that machine learning can classify canine emotional states from both manually coded and automated methods, offering potential for future automated welfare monitoring. HighlightsO_LIMachine learning approaches classify firework-related fear in dogs reliably C_LIO_LIEar position and blinking are key indicators C_LIO_LIEthogram-based coding yielded stronger predictions than automatically detected facial landmarks C_LIO_LIAutomated landmark analysis shows potential for scalable welfare monitoring C_LI O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=160 SRC="FIGDIR/small/683931v1_ufig1.gif" ALT="Figure 1"> View larger version (48K): org.highwire.dtl.DTLVardef@ec9ab8org.highwire.dtl.DTLVardef@1a1bc0corg.highwire.dtl.DTLVardef@140c1e5org.highwire.dtl.DTLVardef@79d23e_HPS_FORMAT_FIGEXP M_FIG Graphical abstract C_FIG Subject areasEmotional expression {middle dot} Behavioural classification {middle dot} Machine learning {middle dot} Facial landmarks {middle dot} Facial expressions

animal behavior and cognition↗

bioRxiv2024

Interferon-induced activation state of circulating dendritic cells and monocytes triggered by yellow fever vaccination correlates with early protective antibody responses

Yellow fever vaccination provides long-lasting protection and is a unique model for studying the immune response to an acute RNA virus infection in humans. To elucidate the early innate immune events preceding the rapid generation of protective immunity, we performed transcriptome analysis of human blood dendritic cell (DC) and monocyte subpopulations before and 3, 7, 14 and 28 days after vaccination. We detected temporary upregulation of IFN-stimulated genes (ISG) in all DC and monocyte subsets on day 3 and 7 after vaccination as well as cell type specific responses and temporal dynamics. Single cell RNA sequencing revealed rapid appearance of activated DC and monocyte clusters dominated by ISGs, inflammatory chemokines and genes involved in antigen processing and presentation. This was confirmed by flow cytometric analysis in a large cohort of vaccinees. We identified SIGLEC1/CD169 upregulation as a sensitive indicator of the transient IFN-induced activation state elicited in DCs and monocytes by YF17D vaccination correlating with early protective IgM antibody responses.

immunology↗

bioRxiv2021

Germ plasm anchors at tight junctions in the early zebrafish embryo

The zebrafish germline is specified during early embryogenesis by inherited maternal RNAs and proteins collectively called germ plasm. Only the cells containing germ plasm will become part of the germline, whereas other cells will commit to somatic cell fates. Therefore, proper localization of germ plasm is key for germ cell specification and its removal is critical for the development of soma. The molecular mechanism underlying this process in vertebrates is largely unknown. Here we show that germ plasm localization in zebrafish is similar to Xenopus and amniotes but distinct from Drosophila. We identified non muscle myosin II (NMII) and tight junction (TJ) components as interaction candidates of Bucky ball (Buc), which is the germ plasm organizer in zebrafish. Remarkably, we also found that TJ protein ZO1 colocalizes with germ plasm and electron microscopy (EM) of zebrafish embryos uncovered TJ like structures at early cleavage furrows. In addition, injection of the TJ-receptor Claudin-d (Cldn-d) produced extra germ plasm aggregates. Our findings discover for the first time a role of TJs in germ plasm localization.

developmental biology↗

bioRxiv2019

Effects of breed, management and personality on cortisol reactivity in sport horses

Sport horses need to fulfill high physical and psychological requirements during training and competition. These as well as certain conditions of modern husbandry may affect their wellbeing. Here we aimed to (1) evaluate effects of demographic and management factors as well as personality traits on stress reactivity of sport horses, (2) investigate if elite sport horses have elevated stress levels compared to amateur sport horses, and (3) assess whether different equestrian disciplines differentially influence horses adrenal cortex responsiveness. For this purpose, we visited 149 healthy elite (n=94) and amateur (n=54) sport horses in Switzerland and performed an adrenocorticotropic hormone (ACTH) stimulation test. Additionally, a person who was familiar with the horse completed a questionnaire about demographic and management factors and horses personality traits. Linear models were calculated to assess associations between the questionnaire data and salivary cortisol 60 and 90 minutes after ACTH stimulation. While the model at T90 was not significant, post-stimulatory cortisol after 60 min appears most informative in line with a previous study and was significantly affected by the horses breed and by three management factors: "number of riders", "hours spent outside" and "group housing" (adjusted r2 =15%, p<0.001). Thoroughbred and Warmblood horses displayed an increased adrenal response compared to Franches-Montagnes horses. Horses with several riders had a less pronounced reaction than horses with one rider, and horses that spent more time outside had a decreased response compared to horses that were stabled most of the time. Horses living in groups showed higher post-stimulatory cortisol values than horses that were housed singly. However, no significant associations of cortisol responsiveness with personality traits were found, and neither the horses use as elite or as amateur sport horses nor the discipline had an effect on the cortisol response. This suggests that optimizing husbandry conditions may be more important for improving horses welfare than changing their use.

animal behavior and cognition↗

bioRxiv2019

Effectiveness of treatments for firework fears in dogs

An online questionnaire survey investigated (1) management and (2) treatment methods for firework fears in dogs employed by dog owners and their (perceived) effectiveness. A PCA on data from 1225 respondents revealed four management strategies (i.e. interventions during firework exposure): the principal components "Environmental modification" (e.g. providing a hiding place, keeping windows and blinds closed, and playing music), "Feed/Play" (providing the dog with chews, play and food during fireworks in general, as well as contingent on loud bangs), "Alternative" (use of calming nutraceuticals, pheromones, herbal products, homeopathic products, Bach flowers, and essential oils) and "Interaction" (allowing body contact, petting and talking to the dog when loud bangs occurred). To explore possible effects of these management methods on fear development, the components were correlated with a score for fear progression. Of the four components, only "Feed/Play" was statistically associated with an improvement in fear responses to fireworks. To evaluate the effectiveness of various treatment strategies, owners were asked to select from a range of options which interventions they had used and whether they considered them as effective. With prescription medication (N=202), improvements were noted by 69% of owners, with high success rates reported for the most frequently prescribed drugs, alprazolam (91%) and Sileo(R) (74%). While individual products were not evaluated, the reported success rates for the categories "pheromones" (N=316), "herbal products" (N=282), "nutraceuticals" (N=211), "essential oils" (N=183), "homeopathic remedies" (N=250) and "Bach flowers" (N=281) were all in the range of 27-35%, which is not higher than would be expected based on a placebo effect. Pressure vests were deemed as effective by 44% of respondents (N=300). Counterconditioning (providing desirable stimuli after the occurrence of noises) was the most successful training technique according to the owners (N=694), with a reported effectiveness of over 70%. Relaxation training (N=433) was reported to be almost as successful at 69%, while noise CDs (N=377) were effective in 55% of cases. Thus, counterconditioning, relaxation training and anxiolytic medication appear to be the most effective strategies in the treatment of firework fears in dogs. On this basis it is recommended that ad-hoc counterconditioning and relaxation training should complement the standard behavioral technique of desensitization/ counterconditioning with noise recordings. HighlightsO_LIAn online survey on treatment options for firework fears in dogs was performed C_LIO_LIFeeding or playing with dogs during fireworks was associated with fear improvement C_LIO_LISuccess was highest for ad-hoc counterconditioning, relaxation training and medication C_LIO_LISuccess was similar for pheromones, nutraceuticals and other alternative products C_LIO_LISuccess rates for these alternative products are consistent with a placebo effect C_LI

animal behavior and cognition↗

bioRxiv2019

Not a one-way road - severity, progression and prevention of firework fears in dogs

Noise fears represent a highly prevalent welfare problem in dogs. An online survey was performed to explore severity and progression of firework fears in dogs, and relationships with demographics, health, behaviour problems, and owners training efforts to prevent or alleviate firework fears. 1225 responses were analysed. Fifty-two percent of dogs were at least partially affected by firework fears, and the great majority developed a fear of fireworks in the first year of life, with a decreasing frequency of new occurrences up until seven years, and only few newly affected dogs beyond this age. While almost three quarters of fearful dogs had recovered by the next morning, recovery took up to one day in 10%, up to one week in 12%, and several weeks or even months in >3%. Univariate analyses indicated a significant effect of breed group, age, sex, neuter status, origin and age at acquisition on severity of firework fears in dogs. However, binomial models including multiple predictors of presence/ absence of firework fears identified only age, breed group (mixed breeds being most affected), health problems, and an interaction between health problems and age as significant predictors. This discrepancy might be explained by collinearities of predictors and underlying differences between mixed-breed dogs and purebreds, such as mixed breeds being acquired from shelters more often, being adopted at higher ages, and being neutered more often. Firework fears are highly correlated with fears of gunshots and thunder, and to a low extent with fears of other noises, but not with any other behavioural problems. Both improvement and deterioration of firework fears were frequently reported. While an early age of onset and breed differences point to a strong genetic contribution to firework fears, training puppies or non-fearful adults to associate the noise with positive stimuli is highly effective in preventing later development of firework fears.

animal behavior and cognition↗