Applied Animal Behaviour Science最新文献

{"title":"Development of experimental parameters for conditioned place aversion testing in neonatal goat kids","authors":"Erica Schmidt ,&nbsp;Beth A. Ventura ,&nbsp;Benjamin Lecorps ,&nbsp;Whitney A. Knauer","doi":"10.1016/j.applanim.2025.106749","DOIUrl":"10.1016/j.applanim.2025.106749","url":null,"abstract":"<div><div>Conditioned place aversion (CPA) is a behavioral assay used to investigate animals’ affective responses. Animals are typically conditioned to differing experiences in different places, whereupon they are expected to avoid the place where they experienced the most negative (or least positive) experience based on their memory of the events. This approach has been used to assess the affective component of pain in farm animals but has not yet been applied to neonatal goat kids. As animals’ preferences for different environments may be affected by several environmental factors, our objectives were to assess 1) whether side (left or right) and color (red, white, yellow, or blue) influenced kids' preferences and 2) whether kids should be acclimated to the CPA test apparatus alone or in pairs based on their exploratory and vocalization responses (used as proxy measures of stress). 96 goat kids (8 ± 4d) were randomly allocated to testing in pairs (n = 24 pairs) or alone (n = 48 kids) for a 15-minute acclimation test in a three-compartment pen (two colored side compartments linked by a middle neutral compartment). Kids spent more time in the blue compartment compared to yellow but showed no statistical difference in time spent in blue compared to white or red compartments. Additionally, kids displayed a preference for the right compartment compared to the left, regardless of compartment/color combination. When tested alone as compared to in pairs, kids vocalized five times more and halved their number of visits to side compartments. We suggest that of the color combinations examined in the current study, blue and white appear to be suitable choices for use in future CPA experiments, but side preference must be accounted for in experimental design. Further, acclimating kids to CPA tests in pairs, rather than alone, is recommended to reduce stress and promote exploration. Further work is needed to confirm whether the side bias found here persists in other testing contexts (e.g., after conditioning), and to clarify the impact of testing conditioned place aversion in individual goat kids.</div></div>","PeriodicalId":8222,"journal":{"name":"Applied Animal Behaviour Science","volume":"292 ","pages":"Article 106749"},"PeriodicalIF":2.2,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144679169","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hold your horses: The effect of play behaviour in horses (Equus caballus) under imposed stress","authors":"Jodi Anne Howard,&nbsp;Neville Pillay","doi":"10.1016/j.applanim.2025.106752","DOIUrl":"10.1016/j.applanim.2025.106752","url":null,"abstract":"<div><div>Horses (<em>Equus caballus</em>) are prone to acute and chronic stress, particularly in equestrian sports, raising significant welfare concerns. We investigated whether and how play can mitigate acute acoustic stress and enhance decision-making in horses. We studied horses in two different stabling and working conditions (intensively vs. extensively managed) and recorded their behaviours in a Y maze for a food reward in three sequential treatments: baseline (no stressor), stress (exposure to a short-term acoustic stressor) and solitary object play with a large ball (exposure to the stressor followed by play). We recorded behavioural diversity, latency to approach the decision point (before choice) and food reward arm, behaviours associated with positive and negative emotional state and overall choices made (decisions) in the maze. Decision-making was significantly better in the play treatment than in both the baseline and stress treatments. Horses in the stress treatment exhibited a greater diversity of behaviours associated with negative emotional states and poorer decision-making compared to the play and baseline treatments. Additionally, intensively managed horses under more constrained conditions, were more stressed than those extensively managed. Our findings suggest that play can effectively reduce stress and improve decision-making in horses, depending on their housing conditions, and highlight the importance of play for equine welfare.</div></div>","PeriodicalId":8222,"journal":{"name":"Applied Animal Behaviour Science","volume":"292 ","pages":"Article 106752"},"PeriodicalIF":2.2,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144654872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The duration of urbanization influences avian escape behaviour","authors":"Shuang Yang ,&nbsp;Yuran Liu ,&nbsp;Wei Liang","doi":"10.1016/j.applanim.2025.106747","DOIUrl":"10.1016/j.applanim.2025.106747","url":null,"abstract":"<div><div>The increasing pace and scale of urbanization may have a significant impact on the birds that live within it, forcing them to adapt their behaviour to cope with the opportunities and challenges of urbanization. Understanding the impact of urbanization on bird behaviour and the process of behaviour adaptation to human disturbance is crucial for conservation and management of urban-dwelling birds. It also helps to further understand how wildlife responds to human-induced environmental changes and promotes the coexistence of wildlife and human beings. In this study, we selected urban areas with significant different initiation times of urbanization as research sites, and flight initiation distance (FID) was observed for common ground-foraging birds in these cities. The results showed that the duration of urbanization significantly affected the FIDs of birds to human in cities. Birds living in areas with longer periods of urbanization were more tolerant to human disturbance. Our study suggests that the duration of urbanization has an important influence on the escape behavior of birds to human disturbance.</div></div>","PeriodicalId":8222,"journal":{"name":"Applied Animal Behaviour Science","volume":"292 ","pages":"Article 106747"},"PeriodicalIF":2.2,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144633913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Short- or long-term affect? Disentangling the effects of emotion and mood on pigs’ decisions on a Judgement Bias Task","authors":"Sara Hintze ,&nbsp;Katharine Creagh ,&nbsp;Lorenz Gygax ,&nbsp;Jean-Loup Rault","doi":"10.1016/j.applanim.2025.106748","DOIUrl":"10.1016/j.applanim.2025.106748","url":null,"abstract":"<div><div>The Judgement Bias Task (JBT) is a promising proxy measure of animals’ affective states, a growing field in animal welfare science and beyond. However, it remains unclear if judgement biases are predominantly affected by long-term mood, short-term emotions or a combination of both. This study aimed to systematically disentangle the effect of mood- and emotion-inducing treatments on pigs’ decisions on a JBT using positive human-pig interactions as affect manipulation. Across three batches, thirty-six pigs were trained on a spatial Go/No-go task with active trial initiation. During the three weeks of training and during testing, 12 pigs were administered five minutes of positive interactions daily with a familiar human (MoodPlus), whereas the remaining 24 pigs did not receive such treatment (MoodMinus). When pigs were tested on the JBT, all 12 MoodPlus and 12 of the MoodMinus pigs received three test sessions that were preceded by five minutes of positive interactions (EmoPlus) and three test sessions without positive interaction before (EmoMinus). The remaining 12 MoodMinus pigs were allocated to a control group, which did not receive any specific positive interaction treatment. Thirty pigs (83 %) reached the learning criterion and were tested across six test sessions. Pigs from all treatment groups showed highly “optimistic” responses to all ambiguous cues, leading to a ceiling effect, which may have overshadowed potential treatment differences (all effects apart from cue type: <span><math><msubsup><mrow><mi>χ</mi></mrow><mrow><mn>1</mn></mrow><mrow><mn>2</mn></mrow></msubsup></math></span> ≤ 1.75, p ≥ 0.19). Results from Human Approach and Avoidance Tests at the end of the study and the analysis of the behaviour of pigs during EmoPlus sessions indicated that all pigs, independent of treatment, had developed a positive relationship with the experimenter over the course of the study. These results suggest that positive human-animal interactions may not be an ideal treatment in the context of JBT when training requires regular contact with humans. MoodMinus pigs tended to respond more “optimistically” in EmoMinus sessions than Control pigs (χ²₁ = 3.58, p = 0.06), which may indicate a carry-over effect from EmoPlus to EmoMinus sessions. We call for future studies with a different treatment than human-animal interactions that implements both long- and short-term interventions in a systematic way to disentangle the effect of mood and/or emotion on judgement biases.</div></div>","PeriodicalId":8222,"journal":{"name":"Applied Animal Behaviour Science","volume":"292 ","pages":"Article 106748"},"PeriodicalIF":2.2,"publicationDate":"2025-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144694460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of selection for divergent levels of social motivation on behavioral repertoire and synchronization in Japanese quail (Coturnix japonica)","authors":"Jeanne Seressia ,&nbsp;Marie Gellé ,&nbsp;Fabien Cornilleau ,&nbsp;Julie Lemarchand ,&nbsp;Léa Lansade ,&nbsp;Per Jensen ,&nbsp;Ludovic Calandreau ,&nbsp;Vitor Hugo Bessa Ferreira","doi":"10.1016/j.applanim.2025.106750","DOIUrl":"10.1016/j.applanim.2025.106750","url":null,"abstract":"<div><div>Behavioral synchronization occurs when individuals perform the same behavior simultaneously and in close proximity. It is widely recognized as a key mechanism that fosters social cohesion, coordination, and cooperation within groups, providing substantial adaptive benefits. However, since individuals within a group often exhibit inter-individual differences in social tendencies, these variations may influence group organization and the extent to which synchronization occurs. Here, we investigated how genetic selection for social motivation (i.e., an individual’s internal drive to seek contact, approach and remain close to a group of conspecifics) in Japanese quail (<em>Coturnix japonica</em>) impacts their behavioral repertoire and their behavioral synchronization, by comparing 10 trios (groups of three) constituted of individuals selected for high social motivation (S+) and 10 trios constituted of individuals selected for low social motivation (S-). For this purpose, trios were placed for 24 consecutive hours in an arena filled with wood shavings and providing <em>ad libitum</em> access to feed and water. Birds’ behaviors were recorded and analyzed during four one-hour time windows (hour 1: 8:30–9:30 am, hour 2: 11:00–12:00 am, hour 3: 1:30–2:30 pm and hour 4: 4:00–5:00 pm). Results revealed that S- quail exhibited more locomotion behaviors, while S+ quail displayed more inactivity behaviors and particularly \"sit relaxed\" behaviors. Also, S+ individuals had a longer total synchronization duration than S- individuals. Specifically, S+ quail performed more synchronized \"sit relaxed\" behaviors, spent more time in this state and remained synchronized longer during a \"sit relaxed\" bout compared to S- quail. The S+ group also exhibited a significantly higher overall Kappa coefficient, as well as a higher Kappa coefficient for the behavior \"Sit relaxed\", both of which significantly differed from 0, indicating a structured pattern of behavioral synchronization consistent with coordinated group dynamics. Notably, during synchronization bouts of the behavior \"Sit relaxed\", birds reduced inter-individual distances, indicating an active preference for staying closer together during this activity. Overall, these findings suggest that individuals with higher social motivation are more likely to engage in synchronized behaviors, particularly during resting behaviors, which may promote close proximity and strengthen social bonds. Such synchronization may foster social cohesion and lead to more harmonious and stable group dynamics. Further studies will be necessary to better elucidate these effects and confirm these different hypotheses. This research highlights the critical role of individual differences in social motivation in shaping collective behavior. These insights enhance our understanding of animal social dynamics and could contribute to more effective management strategies in animal husbandry.</div></div>","PeriodicalId":8222,"journal":{"name":"Applied Animal Behaviour Science","volume":"292 ","pages":"Article 106750"},"PeriodicalIF":2.2,"publicationDate":"2025-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144665973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A keypoint detection-based approach for real-time aggressive behavior identification in goats","authors":"Hongchun Qu ,&nbsp;Ansong Leng ,&nbsp;Yutong Deng ,&nbsp;Xiuping Yin ,&nbsp;Xiaoming Tang ,&nbsp;Shidong Zhai","doi":"10.1016/j.applanim.2025.106745","DOIUrl":"10.1016/j.applanim.2025.106745","url":null,"abstract":"<div><div>This study addresses the existing challenges in animal aggression behavior detection by proposing a real-time recognition method based on keypoint detection. Traditional detection methods based on static whole-frame images are limited in their ability to analyze dynamic processes, often leading to false positives, where non-aggressive behaviors are misclassified as aggression. While algorithms incorporating Long Short-Term Memory (LSTM) networks improve accuracy, they suffer from poor real-time performance due to the need for comprehensive analysis of sequential video data, resulting in a high computational burden and an inability to pinpoint specific aggression events. Furthermore, many existing approaches require artificial interventions during the data collection phase, such as increasing animal density to provoke aggression, which can induce stress responses in the animals and generate data that deviate from natural behaviors, thus failing to accurately reflect authentic social interactions and conflict mechanisms. To overcome these challenges, this study introduces a novel method that detects keypoints on the head and body of goats, analyzing the movement relationships between these keypoints in real-time to identify aggressive behavior without the need for artificial intervention. Experimental results demonstrate that this approach outperforms existing methods in terms of accuracy, recall rate, and false positive rate, while offering superior real-time performance and robustness. Moreover, the proposed method is highly extensible, not only applicable to aggression detection but also capable of analyzing other daily behaviors of goats through keypoint data. To contribute to the advancement of the field of animal behavior studies, we have made publicly available a dataset containing keypoint information of goats, providing valuable resources for future research.</div></div>","PeriodicalId":8222,"journal":{"name":"Applied Animal Behaviour Science","volume":"292 ","pages":"Article 106745"},"PeriodicalIF":2.2,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144614779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Usage of outdoor run and health aspects of fattening pigs fed whole plant vetch silage or straw as roughage","authors":"Marie-Theres Machner,&nbsp;Karen Aulrich,&nbsp;Ralf Bussemas,&nbsp;Julika Wiskandt,&nbsp;Stephanie Witten","doi":"10.1016/j.applanim.2025.106742","DOIUrl":"10.1016/j.applanim.2025.106742","url":null,"abstract":"<div><div>Advantages of feeding protein-rich whole plant silages in pig fattening, such as clover-grass silage, have been investigated in the past. However, vetch whole plant silage has not yet been under investigation. Vetch has many advantages from a crop production perspective and is a potential fibre- and protein-rich feedstuff for pigs. This study aimed to investigate if a) vetch silage compared to straw as roughage has positive effects on the outdoor run usage and the occurrence of foraging behaviour in the outdoor run, b) the duration of roughage intake and the amount of roughage consumed depends on the vetch species, and c) health aspects (skin lesions and lameness) are affected by the vetch silage compared to straw. A total of 120 mixed-sex fattening pigs [(Landrace × Large White) × Pietrain] were studied over two trials conducted throughout 11 months. In each trial, three dietary treatments were tested: silage made from <em>Vicia sativa</em>, silage made from <em>Vicia pannonica</em>, and straw as a control roughage. Each treatment included two groups of ten pigs per trial, resulting in 40 pigs per treatment. The roughage was offered to the animals in all groups from a rack in the outdoor run. The observation based on interval photos from video recordings of the outdoor runs. The usage of the outdoor runs and the display of different behaviours were determined on pen-basis by instantaneous scan sampling. Additionally, the time period until the silage was totally consumed was evaluated and twice a week silage leftovers were collected to estimate amounts of silage intake. The skin lesions of each pig were scored every week during the trial period according to the Welfare Quality® Assessment protocol.</div><div>In December, the outdoor runs were used significantly more often in experimental groups, which were provided silage, than in the control groups, which were provided straw (p &lt; 0.05). In May, the animals of the groups that received <em>Vicia pannonica</em> showed more frequent foraging behaviour than the animals of the control groups (p &lt; 0.05). Neither the duration of silage intake nor the amount of consumed silage differed between the two experimental groups. Feeding vetch silage to fattening pigs had no effect on body lesions or the occurrence of lameness. The positive effect of vetch whole plant silage on outdoor run usage and foraging behaviour indicate that pigs are interested in this feedstuff, which can thus be an enrichment.</div></div>","PeriodicalId":8222,"journal":{"name":"Applied Animal Behaviour Science","volume":"292 ","pages":"Article 106742"},"PeriodicalIF":2.2,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144662333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"I spy with my little eye: Humans follow a horse-specific visual search pattern when examining facial expressions of horses with different levels of pain","authors":"Debby D.M. Gudden ,&nbsp;Inga A. Wolframm ,&nbsp;Johannes P.A.M. van Loon ,&nbsp;Elizabeth M. van Grevenhof ,&nbsp;Madita Everding ,&nbsp;Marion Y. Ballast ,&nbsp;Peter R. Reuter ,&nbsp;P. René van Weeren ,&nbsp;Saskia S. Arndt","doi":"10.1016/j.applanim.2025.106744","DOIUrl":"10.1016/j.applanim.2025.106744","url":null,"abstract":"<div><div>In daily interaction with horses, humans primarily rely on facial expression as a non-verbal equine cue for emotional information. Difficulties in correctly recognizing these signals might arise due to the species-specificity of facial cues, possibly leading to diminished equine welfare and health. This study aimed to explore human visual search patterns when assessing equine facial expressions indicative of various pain levels, utilizing eye-tracking technology. Hundred and eight individuals (N = 108), classified into three groups (affinity with horses (N = 60), pet owners with no affinity with horses (N = 32), and individuals with no affinity with animals (N = 16)) participated in the study; with their eye movements recorded using eye tracking glasses they evaluated four photos of horses with different levels of pain. Error score, calculated by comparing participant scores to Gold Standard Visual Analogue Score levels and fixation metrics (number of fixations and duration of fixations) were analysed across the four photos, participant group and Areas of Interest (AOIs): eyes, ears, nostrils, and mouth. Statistical analysis utilized linear mixed models. Highlighting the critical role of the eyes as key indicators of pain, findings showed that the eyes played a significant role in assessing equine emotional states, as all groups focused on them for a longer time and more frequently compared to other facial features. Also, participants showed a consistent pattern in how they looked at a horse's face, first focusing on the eyes, then the ears, and finally the nose/mouth region, indicating a horse-specific pattern. Moderate pain was assessed with similar accuracy across all groups, indicating that these signals are broadly recognizable. Nevertheless, non-equestrians faced challenges with recognizing the absence of pain, possibly highlighting the role of experience in interpreting subtle equine expressions. The study's limitations, such as variability in assessment conditions may have impacted findings. Future work could further investigate why humans follow this visual search pattern and whether they recognize the significance of a horse's ears. Additionally, emphasis should be placed on developing targeted training interventions to improve equine pain recognition, possibly benefiting equine welfare and health.</div></div>","PeriodicalId":8222,"journal":{"name":"Applied Animal Behaviour Science","volume":"292 ","pages":"Article 106744"},"PeriodicalIF":2.2,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144605901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The impact of delaying behavior rehabilitation onset on fear and outcome measures in dogs in a shelter setting","authors":"Kristen Collins,&nbsp;Katherine Miller,&nbsp;Bailey H. Eagan,&nbsp;Emily Patterson-Kane,&nbsp;Tristan Rehner-Fleurant,&nbsp;Victoria Cussen,&nbsp;Pamela Reid","doi":"10.1016/j.applanim.2025.106743","DOIUrl":"10.1016/j.applanim.2025.106743","url":null,"abstract":"<div><div>Undersocialized domestic dogs (<em>Canis lupus familiaris</em>) often experience moderate to severe fear in response to everyday stimuli, and their welfare may suffer. In an animal shelter setting, fearful behavior can also reduce dogs’ chances of adoption and, thus, increase the risk of humane euthanasia. Given that dogs are commonly relinquished to shelters as a result of fear-related behaviors, research is needed to assess the efficacy of behavior modification treatment for undersocialized fearful dogs in the shelter environment. Because dogs may demonstrate behavior change as they acclimate to the shelter after intake, such research must parse out the effects of acclimation from those of a structured treatment protocol. This experimental study examined the change in the fearful behavior of dogs that had behavior modification treatment beginshortly after intake with that of dogs that experienced a two or four-week “settling in” period before treatment began. We also compared the delayed treatment groups by key outcome measures including weeks in treatment (WIT), overall time to graduation from the behavior modification program (TTG), proportion of dogs graduated, and proportion of dogs adopted.</div><div>Two cohorts of dogs (New Jersey [NJ] facility n = 260, North Carolina [NC] facility n = 114) admitted to a behavioral rehabilitation center were pseudo-randomized into behavior modification treatment onset groups of immediate, two-, or four-week delay. All dogs received standard shelter care and in-kennel enrichment, behavior modification treatment, anxiety-reducing medication, and repeated behavior evaluations to assess their fear of several everyday stimuli that pet dogs encounter in home environments. Dogs in the immediate onset treatment group demonstrated a quicker reduction in measures of fear compared to dogs in the delay groups, suggesting that behavior modification, not acclimation to the shelter environment, resulted in the reduction in fear. Delaying treatment onset resulted in lower WIT for dogs in the NJ cohort, but not the NC cohort. No differences were observed in TTG between immediate treatment and delay groups. Treatment onset did not affect the proportion of dogs graduated or adopted. While WIT were slightly lower for dogs with delayed treatment onset, immediate treatment onset reduced dogs’ fear more expeditiously. Therefore, if shelter resources allow, starting behavior modification as soon as possible may be the most ethical option, with quality of life in mind.</div></div>","PeriodicalId":8222,"journal":{"name":"Applied Animal Behaviour Science","volume":"292 ","pages":"Article 106743"},"PeriodicalIF":2.2,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144605900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Social structure and interactions of laying hens: Limited differences between small and large groups","authors":"Klara J. Grethen ,&nbsp;Yamenah Gómez ,&nbsp;Michael J. Toscano","doi":"10.1016/j.applanim.2025.106741","DOIUrl":"10.1016/j.applanim.2025.106741","url":null,"abstract":"<div><div>As the egg-laying industry transitions from cages to cage-free housing, laying hens are increasingly housed in large groups. Cognitive limitations may impair recognition of conspecifics in such large groups, raising questions on the hens’ ability to form dominance hierarchies as in natural settings. While some studies suggest reduced aggression in larger groups and potential changes in assessment of conspecifics, systematic investigations of social structures and its impact on individuals are lacking. Therefore, we assessed social interactions and structure of 418 White Leghorn hens divided into six pens (three small groups of 20, three large groups of ∼120). From 10–12 and at 24 weeks of age (WoA), we observed social interactions across all hens within a pen and employed Elo ratings, a ranking approach suited for large groups, to assess dominance rank. Furthermore, using 14 focal hens from each group (N = 84), at 16 WoA we tested fear responses (latency to emerge; choice between food and conspecific) and at 26 WoA assessed recognition (choice between flockmate and non-flockmate) and measured body weight and comb size. Contrary to expectations, social structures seemed to be consistent across small and large groups. Within each group, steepness (&gt;0.79) and transitivity (&gt;0.70) were high, indicating hierarchical structures across both group sizes. Top-ranking individuals accounted for over 70 % of interactions in both group sizes and aggression followed a downward heuristic, demonstrating uniform aggression against lower-ranking individuals irrespective of group size. Group size did not significantly affect the number of aggressive interactions per individual or the fear responses. We also found no significant effect of weight or comb size on the rank in either group size. However, in the recognition test, hens from large groups tended to spend more time with the first individual encountered, regardless of flock-origin, whereas hens in small groups preferred the flockmate, suggesting that recognisability only influences social decisions in small groups. Taken together, our findings challenge the current notion of reduced aggression in large groups of chickens and suggest that hierarchical structures exist in large groups. The observed social dynamics may pose challenges for low-ranking hens in large flocks, due to the pecking pressure exerted by increased numbers of higher-ranking hens.</div></div>","PeriodicalId":8222,"journal":{"name":"Applied Animal Behaviour Science","volume":"291 ","pages":"Article 106741"},"PeriodicalIF":2.2,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144579886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}