The inflammatory immunity and gut microbiota are associated with fear response differences in laying hens

The fear response is a crucial adaptive mechanism for coping with environmental changes, and the individuals have different levels of fearfulness. The purpose of this study was to determine the status of the immune response and gut health in hens with different fear responses. A total of 80 healthy 75-wk-old native Lindian chickens were individually housed in conventional cages and categorized into high (TH) and low (TL) levels of fearfulness using the tonic immobility (TI) test. The immunological status and intestinal health of the laying hens were assessed, and the intestinal microbial community was sequenced using 16S rRNA testing. The results showed that the immune-related genes of interleukin (IL)-1β, IL-4, IL-6, and IgG were significantly upregulated in the spleen of TH hens compared with hens in the TL group (P < 0.01). The inflammatory immune-related genes Toll-like receptor (TLR)2, TLR4, nuclear factor (NF)-κB, inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, IL-10, and IgG were significantly increased in the intestinal tract, whereas IL-4, IgA, and the intestinal barrier gene claudin-4 were significantly decreased in TH hens (P < 0.05). In addition, serum concentrations of IL-1β, IL-6, IL-10, interferon (IFN)-α and IgG were significantly higher in TH hens (P < 0.01). A high fear response also led to changes in gut microbial diversity, with a higher Simpson's index and lower β-diversity similarity than hens with a low-fear response (P < 0.05). The TH group showed an increase in 8 genera, including Bacillaceae and Coprococcus, whereas the genus Anaerorhabdus decreased (P < 0.05). The gut microbiota has also been associated with gut barrier genes, and inflammatory cytokines. Bartonella stimulates IL-1β and IgG secretion, whereas Lactobacillus inhibits IL-6 secretion, and Coprococcus and Subdoligranulum are associated with the maintenance of intestinal barrier function. The results of this study suggest that laying hens with high fear response levels have a more sensitive immune response and a more enriched gut microbiota, which may have positive effects on adapting to a complex environment.

The Reality of Tonic Immobility in Victims of Sexual Violence: "I was Paralyzed, I Couldn't Move"

Tonic immobility (TI) is a state of temporary, involuntary motor inhibition that occurs in states of intense fear and has been studied among victims of sexual violence. Studies on TI are scarce and mainly focus on rape victims. The present study is a literature review of research that has examined TI in women victims of sexual violence. A database search was carried out using the Preferred data elements for systematic reviews and meta-analyses (PRISMA) method. In order to be included in the analysis, the manuscripts had to deal exclusively with research involving samples of subjects and the study analyzed TI in victims of sexual violence. In all, 11 manuscripts met the above criteria and were included in the review. Research describes that TI is characterized by two factors: fear and immobility. Quantitative research was conclusive in affirming the presence of a state of paralysis and fear in TI. The immobility factor is the determining factor in explaining the victim's lack of defense or resistance and causes effects such as trembling, physical and mental paralysis, inability to vocalize, and eye closure. In addition, TI has been correlated with long-term negative clinical manifestations as victims are more likely to suffer from post-traumatic stress disorder. These findings contribute to an understanding of TI in victims of sexual violence. Therefore, legal and care practitioners must be able to recognize TI to understand the victim's behavior, differentiate it from consent, and to be able to assist in their recovery.

BLAME-LESS STUDY: a two-arm randomized controlled trial evaluating the effects of an online psychoeducation programme for adolescents who have experienced physical/sexual violence or sexual abuse. Rationale, study design, and methods

Background: Victims of physical/sexual violence or sexual abuse commonly experience defense responses that result in feelings of guilt and shame. Although trauma-focused interventions are effective in treating post-traumatic stress disorder symptoms, the presence of trauma-related shame and guilt can potentially hinder the process of disclosure during treatment, thus diminishing their overall effectiveness. It is hypothesized that providing psychoeducation about common defense responses will reduce feelings of shame and guilt, thereby increasing receptivity to trauma-focused treatment.Objective: This paper describes the rationale, study design, and methods of the BLAME-LESS study. The effects of a brief online psychoeducation program will be compared with a waiting-list control group. The intervention aims to reduce feelings of trauma-related shame and guilt that adolescents experience regarding their own defense responses during and after physical/sexual violence or sexual abuse.Methods: Adolescents (12 - 18 years old) with a history of physical/sexual violence or sexual abuse who suffer from trauma-related feelings of shame and guilt can participate in the study. The study follows a two-arm RCT that includes 34 participants. The primary outcomes includes trauma-related feelings of shame and guilt. The secondary outcomes includes PTSD symptoms, anxiety and depression symptoms, traumatic cognitions, readiness to disclose details of memories of the trauma, and motivation to engage in trauma-focused therapy. Assessments take place after screening, at baseline, two weeks after allocation to the intervention or waiting-list, and, only for the waiting-list participants, seven weeks after allocation to the intervention.Conclusions: There is a need for treatment approaches that target trauma-related feelings of shame and guilt. A recently developed brief online psychoeducation program on defense responses during and after trauma offers victims of physical/sexual violence or sexual abuse a free and accessible way to obtain reliable and valid information. The proposed RCT will evaluate the effectiveness of this online psychoeducation program.Trial Registration: Request is pending.

The Behavioral and Productive Characteristics of Japanese Quails (Coturnix japonica) Exposed to Different Monochromatic Lighting

The purpose of this study is to examine the impact of monochromatic illuminations at wavelengths of white (400-700 nm), green (560 nm), yellow (580 nm), blue (480 nm), and red (660 nm) on the performance and behavioral traits of Japanese quails throughout their fattening period. A total of 300 quails in five lighting experimental groups were housed in their conventional rearing cages. Weekly live weights of quails were measured individually, developmental stability was determined, and behavior and fear tests were performed. The body weight averages of quails exposed to blue, green, and yellow light were determined to be greater than those exposed to white and red light (p < 0.05). In terms of the mature weight parameter and the weight of the inflection point of the Gompertz growth model, the averages of the quails exposed to green and blue monochromatic lighting were higher (p < 0.05). The most negative findings on aggressive behavior were observed in birds exposed to monochromatic yellow and red light. Although the body weight of quails exposed to yellow monochromatic lighting was similar to that of quails exposed to green and blue monochromatic lighting, green and blue monochromatic lighting produced the best results in terms of growth, behavior, and developmental stability characteristics. Consequently, it is believed that consistently using green or blue monochromatic lighting programs when raising Japanese quails may provide economic advantages to the producers.

Drop dead! Female mate avoidance in an explosively breeding frog

Males' and females' reproductive strategies may differ, potentially leading to sexual conflict. Increased efforts by males (harassment, forced copulation, intimidation) to gain access to females could even negatively affect female survival and thus lead to reproductive failure for both individuals. In anurans, a higher mortality risk of mating females has been reported in explosive breeding species. During these mating events, several males cling to a female, which are mostly unable to get rid of the unwanted males. This can lead to the female's death. From the literature, it seems that females of explosive breeding frogs have no means to reject unwanted males. Here we describe female mate avoidance behaviours in the European common frog. We observed three female avoidance behaviours, namely 'rotation', 'release call(s)' and tonic immobility (death feigning). These behaviours were significantly associated with smaller female body size, and smaller females were more successful in escaping amplexus. Tonic immobility as a tactic to avoid mating or male harassment has only been observed in a handful of species and only in one other amphibian. Our observations show that females in explosive breeding frogs may not be as passive and helpless as previously thought.

Influence of Perch-Provision Timing on Anxiety and Fearfulness in Laying Hens

Perches can enhance laying hen welfare, but their effectiveness might be age-dependent. We investigated early and late perch access effects on anxiety and fear in pullets through attention bias (AB) and tonic immobility (TI) tests. Pullets (n = 728) were raised with or without multi-level perches: CP (continuous perch access: 0-37 weeks), EP (early perch access: 0-17 weeks), LP (late perch access: 17-37 weeks), and NP (no perch access). AB was conducted in weeks 21 and 37 (n = 84/week), and TI was performed in weeks 20, 25, and 37 (n = 112/week). CP hens fed quicker than EP, LP, and NP in AB at weeks 21 and 37 (p ≤ 0.05). CP and NP feeding latencies were stable, while EP and LP fed faster at week 37 (p ≤ 0.05). CP had the shortest TI at week 20 (p < 0.05). CP and LP had the shortest TI in weeks 25 and 37 (all p ≤ 0.05). Unlike NP, CP reduced anxiety and fear. Adding perches during laying (LP) raised anxiety at week 21, adapting by week 37, and removing pre-laying perches (EP) worsened fear at weeks 20 and 25 and anxiety at week 21, recovering by week 37. Adding or removing perches prior to the lay phase increased fear and anxiety, an effect that disappeared by week 37 of age. Our study indicates that continuous perch access benefits animal welfare compared to no perch access at all.

Increased dietary 5-hydroxytryptophan reduces fearfulness in red junglefowl hens (Gallus gallus)

Our production animals typically suffer poor welfare, which can be revealed by measuring the affective state these animals are in. Negative affective state is linked to poorer welfare, and can be measured as fearfulness. While continuing to research how to improve animal welfare, a compliment to reduce negative affective state could therefore be to reduce individuals' fearfulness, similar to how negative affective states are medicated in humans. A proposed mechanism for this is via the monoaminergic systems. This is based on previous studies across species that have linked the serotonergic system and fear-related behaviour. We here aimed to experimentally manipulate the serotonergic system in red junglefowl hens (Gallus gallus), the main ancestor of all domesticated chickens. We measured fearfulness as latency remaining immobile in a tonic immobility test, and did so both before and after our experimental manipulation. We set out to experimentally manipulate the serotonergic system via sub-chronic dietary treatment of 5-hydroxytryptophan (the precursor to serotonin). Our dietary manipulation of 5-hydroxytryptophan significantly reduced measured fearfulness in the manipulated hens, while latency in tonic immobility did not significantly change in our unmanipulated, control hens. This finding is promising since it indicates that increased tryptophan levels can be used to reduce fearfulness. Additionally, our result suggests that this can be done non-invasively via food (instead of injections), thus presenting a potentially feasible manipulation also for larger settings. Nevertheless, the serotonergic system is complex and its role in modulating behaviour in the fowl should be explored further to evaluate our findings, and more directly explored also in a production setting.

Using shame to extend Martin Conway's self-memory system

We extend Conway's self-memory system by adding theory and data from shame, an emotion that disrupts the internalised ideals of society needed for a positive self-concept. The event that caused 273 undergraduates their greatest amount of shame was analyzed; 66% were not very negative except for producing shame. Ratings of post-event effects, including two measure of self (self-perceived weakness, and centrality to identity) and four clinical symptoms (intrusions, avoidance, anxiety, and depression), were attributed separately to the remembered event, behaviour during the event, and shame from the event. The effects of shame were generally as large as the those of the event and larger than those of the behaviour, demonstrating the importance of shame's effects. The Tonic Immobility Scale (TIS), which measures tonic immobility (i.e., freezing), was obtained for the event that produced the most tonic immobility but that was not the event that caused the most shame. The post-event symptoms measured on the event that caused the most shame and the TIS correlated highly, suggesting that shame and tonic immobility may belong to a cluster of phylogenetically conserved submissive defensive mechanisms that could account for effects currently attributed to goals in self-memory systems.

Why fake death? Environmental and genetic control of tonic immobility in larval lacewings (Neuroptera: Chrysopidae)

Tonic immobility is a passive antipredator strategy employed late in the predation sequence that may decrease individual mortality in prey animals. Here, we investigate how energetic state and genetic predisposition influence antipredator decision-making in green lacewing larvae, Chrysoperla plorabunda (Fitch), using simulated predatory encounters. We demonstrate that tonic immobility is a plastic response influenced by energetic resource limitation. Larvae exposed to 1 or 2 days of food deprivation initiate tonic immobility more often and with less physical provocation than individuals fed ad libitum. Recently molted individuals exposed to food deprivation, the individuals most energetically challenged, engage in tonic immobility at a higher rate than any other group. We also find that variation in antipredator strategy between individuals is partly the result of within-population genetic variation. We estimate the propensity to enter tonic immobility to have a broad-sense heritability of 0.502. Taken together our results suggest that larval lacewings under energetic stress are more likely to engage in tonic immobility. Yet, energetic state does not explain all within-population variation, as individuals can have a genetic predisposition for tonic immobility.

Tonic Immobility as a Defensive Trauma Response to Rape: Bridging Public Health and Law

There is widespread scientific evidence that validates tonic immobility (TI) as part of the trauma response in victims of rape, and criminal justice practitioners are increasingly trained in trauma-informed approaches. Yet, legal and policy definitions of consent do not fully recognize TI during the incident as evidence of nonconsent. Using a systematic review of U.S. law and policy regarding sexual violence and consent, this paper analyzes the substantial legal reform of rape law and definitions of consent, suggesting ways to further integrate TI into existing law and legal practices to improve public health approaches and justice responses for victims.

Differences in innate fear behaviour in native Japanese chickens

1. Comprehensive knowledge of innate fear in chickens has important implications for understanding the adaptation of native Japanese chickens in modern production and behavioural changes caused by modern breeding goals. Innate fear behaviour seen in chicks from six native Japanese chicken breeds;, Ingie (IG), Nagoya (NAG), Oh-Shamo (OSM), Tosa-Jidori (TJI), Tosa-Kukin (TKU) and Ukokkei (UK), were compared with those in two lines of White Leghorn (WL-G and WL-T) in tonic immobility (TI) and open field (OF) tests.2. TI and OF tests were conducted for 267 chicks at 0-1 days of age in the eight breeds. Raw data for four TI traits and 13 OF traits were corrected for environmental factors. Breed differences were analysed by the Kruskal-Wallis test followed by the Steel Dwass post hoc test. Principal component (PC) analyses were conducted.3. The results showed that OSM was the least sensitive to fear in both the TI and OF tests. The WL-G birds showed higher sensitivity to TI fear but lower sensitivity to OF fear. The PC analysis of OF traits classified the tested breeds into three groups: least (OSM and WL-G), moderate (IG, WL-T, NAG, TJI and TKU) and most sensitive (UK).

Tonic immobility (freezing) during sexual and physical assaults produces stronger memory effects than other characteristics of the assaults

Tonic immobility (TI) is a phylogenetically conserved, passive, obligatory defense mechanism commonly engaged during sexual and physical assaults. During TI, people become immobile while remaining conscious and later reexperience intrusive memories of both their assault and of its accompanying immobility. Here we show that this well-studied biological process has powerful effects on memory and other processes. Participants had experienced either a serious sexual (n = 234) or physical (n = 137) assault. For both the assault and its accompanying immobility, the standard measure of the peritraumatic severity of TI correlated between .40 and .65 with post-assault effects on memory, including memory of the assault and memory of the immobility, the two memory-based self-concept measures of self-blame and event centrality, and post-assault anxiety and depression. The correlations with TI were much higher than other peritraumatic characteristics commonly used to predict and describe posttraumatic effects in assaults and other traumas. The results suggest that TI should be considered for a broader, more biologically based and ecologically valid understanding of the effects of trauma on memory and memory-based reactions.

Investment Trade-Off between Mating Behavior and Tonic Immobility in the Sweetpotato Weevil Cylas formicarius (Coleoptera: Brentidae)

Numerous studies have confirmed that the trade-off between anti-predator behavior and mating behavior occurs in certain insect species. This suggests that insects invest more in anti-predator behavior, and fewer resources or time can be used in mating behavior. However, few studies focus on tonic immobility, an important anti-predator behavior in nature, and different stages in mating behavior. Tonic immobility (TI) is considered to be an important anti-predator behavior. Herein, we investigated the relationship between TI and mating behavior in the sweetpotato weevil (SPW), Cylas formicarius. As the first step, we artificially selected SPWs for the longer duration of TI (L-strain) and the shorter duration of TI (S-strain). The effect of courtship and copulation on the duration of TI in two artificial selection strains was tested. Furthermore, we compared the frequency and duration of two mating behaviors in four kinds of pairs (LF×LM, LF×SM, SF×LM, and SF×SM: LM-L-strain male; SM-S-strain male; LF-L-strain female; SF-S-strain female). Finally, we tested insemination success in four kinds of pairs (male and female SPWs from the L-strain or the S-strain). The courtship and copulation significantly reduced the duration of TI. Pairs with males from the L-strain showed lower frequency and longer duration of courtship than pairs with males from the S-strain. Similarly, males from L-strain pairs showed a longer period of copulation than pairs with males from the S-strain. However, there is no significant difference in the frequency of copulation and the success of insemination. These results support that there was a significant trade-off between TI and courtship as well as copulation in the SPW.

Freezing or death feigning? Beetles selected for long death feigning showed different tactics against different predators

Prey evolve antipredator strategies against multiple enemies in nature. We examined how a prey species adopts different predation avoidance tactics against pursuit or sit-and-wait predators. As prey, we used three strains of Tribolium beetles artificially selected for short (short strain) or long (long strain) duration of death feigning, and a stock culture (base population). Death feigning is known to be effective for evading a jumping spider in the case of the long strains, while the present study showed that the long-strain beetles used freezing against a sit-and-wait type predator, Amphibolus venator, in this study. The short- strain beetles were more easily oriented toward predators. The time to predation was also shorter in the short strains compared to the long strains. The results showed that, as prey, the short strains displayed the same behavior, escaping, against both types of predators. Traditionally, death feigning has been thought to be the last resort in a series of antipredator avoidance behaviors. However, our results showed that freezing and death feigning were not parts of a series of behaviors, but independent strategies against different predators, at least for long-strain beetles. We also examined the relationship between a predator's starvation level and its predatory behavior. In addition, the orientation behavior toward and predation rate on the prey were observed to determine how often the predatory insect attacked the beetles.

Personality of hosts and their brood parasites

Brood parasites such as the common cuckoo Cuculus canorus exploit the parental abilities of their hosts, hosts avoid brood parasitism and predation by showing specific behavior such as loss of feathers, emission of fear screams and contact calls, displaying wriggle behavior to avoid hosts or potential prey, pecking at hosts and prey, and expressing tonic immobility (showing behavior like feigning death or rapid escape from predators and brood parasites). These aspects of escape behavior are consistent for individuals but also among sites, seasons, and years. Escape behavior expressed in response to a broad range of cuckoo hosts and prey are consistently used against capture by humans, but also hosts and brood parasites and predators and their prey. An interspecific comparative phylogenetic analysis of escape behavior by hosts and their brood parasites and prey and their predators revealed evidence of consistent behavior when encountering potential parasites or predators. We hypothesize that personality axes such as those ranging from fearfulness to being bold, and from neophobic to curiosity response in brood parasites constitute important components of defense against brood parasitism that reduces the overall risk of parasitism.

Lateralized motor behaviour in the righting responses of the cane toad (Rhinella marina)

This paper reports a series of tests for fore- and hind-limb preferences used by cane toads, Rhinella marina, to assist returning to the righted position after being overturned. We confirm the strong and significant right-handedness reported in this species, which under certain conditions exceeded 90% right-hand preference at the group level. Toads were tested under a variety of conditions including horizontal and inclined surfaces, with and without the opportunity for the forelimbs to grasp a support, in order to assess the effects of different vestibular and proprioceptive input on the strength and direction of fore- and hind-limb preferences. A range of behavioural strategies indicated learning effects; however, the strength or direction of limb preferences did not increase significantly with experience, even in toads retested multiple times. Comparisons with the mammalian condition for limb preferences are discussed with relevance to practice effects and established limb preferences, and to effects associated with arousal or stress. In contrast to the expectation that handedness in toads represents intentional or voluntary preferences, the presence of lateralized central pattern generators in the toads is postulated to explain the different forms of lateralization revealed by our tests.

Characterisation of the Behavioural Effects of a Thoracic Squeeze in Healthy Newborn Piglets

Simple Summary

Firmly squeezing the chests of newborn foals and calves that are showing abnormal behaviours after birth causes them to enter a less-responsive state, characterised by lying down with eyes closed and no limb movements. Once the squeeze is removed, the newborns immediately ‘wake up’ and begin to display more normal behaviours. This response to the thoracic squeeze has also been observed in healthy, normally behaving foals. However, no studies have looked at the effects of the thoracic squeeze in healthy newborns of other mammalian species. We aimed to characterise the behavioural responses of healthy newborn piglets to a thoracic squeeze using the following two methods: a soft fabric rope, or a purpose-made inflation cuff. Behavioural data indicated that all piglets initially became less responsive, with reduced or absent reflex responses to a toe pinch or touch of the eyelid observed in over half of the piglets. The piglets squeezed with the inflation cuff appeared to enter a less-responsive state faster than the piglets squeezed with the rope. These findings suggest that the piglets responded to the thoracic squeeze in a similar way to healthy foals and that this may be a response conserved across multiple precocial mammalian species. Furthermore, the squeeze was found to be safe for inducing a less-responsive state in healthy piglets. This study provides a foundation for exploring the mechanisms underlying the responses to the thoracic squeeze and potential applications whilst performing husbandry procedures.

Abstract

A thoracic squeeze has been observed to cause both healthy and low vigour neonatal foals to enter a ‘less-responsive state’, characterised by loss of posture, eye closure and cessation of movement, from which they rapidly recover to express normal healthy behaviours when the squeeze is released. To date, there have been no systematic studies characterising the responses of healthy neonates of other mammalian species to a thoracic squeeze. We describe the responses of healthy newborn piglets (n = 17) to a standardised application of the thoracic squeeze and evaluate the effect of the method of squeeze application on the response. Neonatal piglets were squeezed around the chest with either a soft fabric rope as has been used in foals (n = 8) or a novel purpose-made inflation cuff (n = 9). Both methods were effective at inducing a less-responsive behavioural state in all piglets, with neural reflexes reduced or absent in over half of them. The inflation cuff appeared to induce the less-responsive state faster than the rope, and more piglets squeezed with the cuff remained in this state for the full 10-min squeeze. These findings suggest that the behavioural response of foals to thoracic squeezing can be generalised to neonates of other precocial mammalian species. This initial study provides a foundation for further research using the inflation cuff to explore mechanisms underlying the thoracic squeeze and ways in which it may be applied whilst performing husbandry procedures.

Effect of Environmental Complexity and Stocking Density on Fear and Anxiety in Broiler Chickens

Barren housing and high stocking densities may contribute to negative affective states in broiler chickens, reducing their welfare. We investigated the effects of environmental complexity and stocking density on broilers' attention bias (measure of anxiety) and tonic immobility (measure of fear). In Experiment 1, individual birds were tested for attention bias (n = 60) and in Experiment 2, groups of three birds were tested (n = 144). Tonic immobility testing was performed on days 12 and 26 (n = 36) in Experiment 1, and on day 19 (n = 72) in Experiment 2. In Experiment 1, no differences were observed in the attention bias test. In Experiment 2, birds from high-complexity pens began feeding faster and more birds resumed feeding than from low-complexity pens following playback of an alarm call, suggesting that birds housed in the complex environment were less anxious. Furthermore, birds housed in high-density or high-complexity pens had shorter tonic immobility durations on day 12 compared to day 26 in Experiment 1. In Experiment 2, birds from high-density pens had shorter tonic immobility durations than birds housed in low-density pens, which is contrary to expectations. Our results suggest that birds at 3 weeks of age were less fearful under high stocking density conditions than low density conditions. In addition, results indicated that the complex environment improved welfare of broilers through reduced anxiety.

The evolutionary origin of near-death experiences: a systematic investigation

Near-death experiences are known from all parts of the world, various times and numerous cultural backgrounds. This universality suggests that near-death experiences may have a biological origin and purpose. Adhering to a preregistered protocol, we investigate the hypothesis that thanatosis, aka death-feigning, a last-resort defense mechanism in animals, is the evolutionary origin of near-death experiences. We first show that thanatosis is a highly preserved survival strategy occurring at all major nodes in a cladogram ranging from insects to humans. We then show that humans under attack by animal, human and ‘modern’ predators can experience both thanatosis and near-death experiences, and we further show that the phenomenology and the effects of the two overlap. In summary, we build a line of evidence suggesting that thanatosis is the evolutionary foundation of near-death experiences and that their shared biological purpose is the benefit of survival. We propose that the acquisition of language enabled humans to transform these events from relatively stereotyped death-feigning under predatory attacks into the rich perceptions that form near-death experiences and extend to non-predatory situations.

The use of behavioral tests of fearfulness in chicks to distinguish between the Japanese native chicken breeds, Tosa-Kukin and Yakido

The aim of this study was to investigate the differences in fearfulness between two Japanese native chicken breeds, Tosa-Kukin (TOK) and Yakido (YKD). In a tonic immobility test, TOK breed chicks showed longer duration and lower induction number compared with YKD. The number of peeps in YKD in an isolation test was lower than that in TOK, whereas there were more bouts of peeping in YKD than in TOK. In a manual restraint test, YKD showed more active responses and initiated peeps and struggling earlier than TOK. The three behavioral tests all indicated that YKD are less fearful than TOK chickens. A latent structures discriminant (OPLS-DA) analysis was used to identify behavioral parameters that contributed to the differences between the breeds. The major parameters were duration and number of inductions in the tonic immobility test and number of struggle in the manual restraint test. These results suggest that three behavioral tests can be used together to evaluate fearfulness of Japanese native breeds of chickens.

Relationship between Range Use and Fearfulness in Free-Range Hens from Different Rearing Enrichments

Inconsistency between the environments of indoor pullet rearing and adult outdoor housing may increase the fearfulness in free-range hens. Rearing enrichments and/or range use may reduce adult fearfulness. Hy-Line Brown^® chicks (n = 1700) were reared inside across 16 weeks with three enrichment treatments: weekly changing novel objects, custom-designed perching/navigation structures, or no additional enrichments. Pullets were transferred to a free-range system at 16 weeks of age, with range access provided from 25 weeks. At 62 weeks, 135 hens were selected from the three rearing treatments and two ranging groups (indoor: no ranging and outdoor: daily ranging) based on individual radio-frequency identification tracking. Individual behavioural tests of tonic immobility, emergence, open field, and novel object (pen level) were carried out on hens. Spectrograms of vocalisations were analysed for the open field test, as well as computer vision tracking of hen locomotion. The results showed few effects of rearing treatments, with outdoor rangers less fearful than indoor hens. The latency to step in the open field test negatively correlated with hen feather coverage. These results show that individual variation in ranging behaviours is present even following rearing enrichment treatments, and subsequent range use might be an indicator of bird fearfulness.

Are memories of sexual trauma fragmented?

Alarmingly high rates of sexual assault on campus have motivated American colleges and universities to take steps to address this serious problem. Yet university administrators have often felt ill-equipped to assess allegations of sexual assault. Unsurprisingly, they have sought the expertise of psychologists who can educate administrative staff about the complexities of traumatic memory. Dr. Rebecca Campbell is among the most influential figures teaching university administrators about sexual trauma and memory. The purpose of this article is to review research pertinent to her views on fragmentation of traumatic memories, and the possible roles of tonic immobility and alcohol consumption on how survivors of sexual assault recall their experience.

Case Report: GABAergic and Serotoninergic Agents for the Treatment and Prevention of Prolonged Dissociative Stupor

Dissociative stupor is a common psychiatric disease lacking an established standard treatment. The lack of therapeutic options may be due to the spontaneous and quick complete remission of most patients. However, since some patients experience multiple relapses and prolonged stupor, investigating potential prevention and treatment options is critical. We reported the case of a 61-year-old Japanese woman who presented with intermittent dissociative stupor for several months. Despite her prolonged symptoms, the administration of lorazepam, escitalopram, and aripiprazole, which selectively enhance GABAergic and serotoninergic activity, improved her stupor and prevented relapse. These findings may help with the treatment of persistent dissociative stupor.

Anti-predator behaviour depends on male weapon size

Tonic immobility and escape are adaptive anti-predator tactics used by many animals. Escape requires movement, whereas tonic immobility does not. If anti-predator tactics relate to weapon size, males with larger weapons may adopt tonic immobility, whereas males with smaller weapons may adopt escape. However, no study has investigated the relationship between weapon size and anti-predator tactics. In this study, we investigated the relationship between male weapon size and tonic immobility in the beetle Gnathocerus cornutus. The results showed that tonic immobility was more frequent in males with larger weapons. Although most studies of tonic immobility in beetles have focused on the duration, rather than the frequency, tonic immobility duration was not affected by weapon size in G. cornutus. Therefore, this study is the first, to our knowledge, to suggest that the male weapon trait affects anti-predator tactics.

Death feigning as an adaptive anti-predator behaviour: Further evidence for its evolution from artificial selection and natural populations

Death feigning is considered to be an adaptive antipredator behaviour. Previous studies on Tribolium castaneum have shown that prey which death feign have a fitness advantage over those that do not when using a jumping spider as the predator. Whether these effects are repeatable across species or whether they can be seen in nature is, however, unknown. Therefore, the present study involved two experiments: (a) divergent artificial selection for the duration of death feigning using a related species T. freemani as prey and a predatory bug as predator, demonstrating that previous results are repeatable across both prey and predator species, and (b) comparison of the death-feigning duration of T. castaneum populations collected from field sites with and without predatory bugs. In the first experiment, T. freemani adults from established selection regimes with longer durations of death feigning had higher survival rates and longer latency to being preyed on when they were placed with predatory bugs than the adults from regimes selected for shorter durations of death feigning. As a result, the adaptive significance of death-feigning behaviour was demonstrated in another prey-predator system. In the second experiment, wild T. castaneum beetles from populations with predators feigned death longer than wild beetles from predator-free populations. Combining the results from these two experiments with those from previous studies provided strong evidence that predators drive the evolution of longer death feigning.

Tonic Immobility and Open Field Responses in Nagoya, White Leghorn, and White Plymouth Rock Chicks

Innate fear responses to tonic immobility (TI) and open field (OF) were evaluated in newly hatched chicks of three breeds with distinct breed origin and genetic relationships. The breeds studied were Nagoya (NAG), a native Japanese breed; White Leghorn (WL), a representative of layers; and White Plymouth Rock (WPR), a parental breed of common broilers. The TI test revealed that WL was the most sensitive to extensive fear evoked by the TI test among the three breeds, followed in order by WPR, and NAG. In contrast, the OF test revealed that NAG was the most sensitive to mild fear evoked by the OF test, followed in order by WPR, and WL. The different fear responses between NAG and WL were supported by minimal phenotypic correlations between TI and OF traits in each breed. These results demonstrated that NAG and WL breeds exhibit extreme and opposite responses to TI and OF fears.

Post-contact immobility and half-lives that save lives

A wide variety of animals become completely immobile after initial contact with a potential predator. This behaviour is considered to be a last-ditch escape strategy. Here, we test the hypothesis that such immobility should have an extremely unpredictable duration. We find that it spans more than three orders of magnitude in antlion larvae. We also analyse the second period of immobility that follows the first bout of immobility, and consider the distributions of both first and second immobility periods within the context of the intermittence that characterizes the movement of most organisms. Both immobility durations were fitted best by exponential distributions. Therefore, both were characterized by high variability and hence, unpredictability. The immobility half-life, its mean duration and standard deviation were greater for the first than the second immobility. Furthermore, individual consistency was weak or absent in repeated measures of the first immobility and between the first and second immobilities. Our quantitative approach can be replicated across taxa and would help link an understanding of immobility after an initial predator contact in both vertebrates and invertebrates. To facilitate this, we contend that the terminology should be simplified, and we advocate the use of the term post-contact immobility (PCI).

Strange-face illusions during eye-to-eye gazing in dyads: specific effects on derealization, depersonalization and dissociative identity

Experimentally induced strange-face illusions can be perceived when two individuals look at each other in the eyes under low illumination for about 10 minutes. This task of subject-other eye-to-eye gazing produces the following perceptions by the subject: (i) mild to huge deformations and color/shape changes of face and facial features; (ii) lifeless, unmoving faces and immaterial presences akin to out-of-body experiences; (iii) pseudo-hallucinations, enlightened 'idealized' faces and personalities - rather than the other's actual face. Dissociative phenomena seem to be involved, whereas the effects of non-pathological dissociation on strange-face illusions have not yet been directly investigated. In the present study, dissociative perceptions and strange-face illusions were measured through self-report questionnaires on a large sample (N = 90) of healthy young individuals. Results of correlation and factor analyses suggest that strange-face illusions can involve, respectively: (i) strange-face illusions correlated to derealization; (ii) strange-face illusions correlated to depersonalization; and (iii) strange-face illusions of identity, which are supposedly correlated to identity dissociation. The findings support the separation between detachment and compartmentalization in dissociative processes. Effects of gender show that strange-face illusions are more frequent in men with respect to women if dyads are composed of individuals of different-gender. Furthermore, drawings of strange-faces, which were perceived by portrait artists in place the others' faces, allowed a direct illustration of examples of dissociative identities. Findings are discussed in relation to the three-level model of self-referential processing.

Tonic Immobility in PTSD: Exacerbation of Emotional Cardiac Defense Response

Among defensive behaviors, tonic immobility (TI) is considered the last defensive resort when life is at extreme risk. Post-Traumatic Stress Disorder (PTSD) is the main psychiatric consequence resulting from exposure to traumatic events. Increasing evidence indicate an association between peritraumatic tonic immobilility and severity of PTSD. Cardiac defense response, a reactivity to perceived danger or threat, has been studied by recording heart rate changes that follows the presentation of an unpredictable intense auditory aversive stimulus. The aim of this study was to investigate potential distinctiveness in cardiac defense response among PTSD patients who presented – compared to those that did not – TI reaction in the laboratory setting. Patients (N = 17) completed the TI questionnaire for signs of immobility elicited by passive listening to their autobiographical trauma script. After a while, they were exposed to an intense white noise, while electrocardiogram was recorded. The heart rate during the 80 s after the noise, subtracted from baseline, was analyzed. Higher reports of TI to the trauma script were associated with stronger and sustained heart rate accelerations after the noise. The effects on cardiac defense response add to increasing evidence that some PTSD patients are prone to repeated re-experiences of TI, which may implicate in a potentially distinct pathophysiology and even a new PTSD subtype.

Genetical Genomics of Tonic Immobility in the Chicken

Identifying the molecular mechanisms of animal behaviour is an enduring goal for researchers. Gaining insight into these mechanisms enables us to gain a greater understanding of behaviour and their genetic control. In this paper, we perform Quantitative Trait Loci (QTL) mapping of tonic immobility behaviour in an advanced intercross line between wild and domestic chickens. Genes located within the QTL interval were further investigated using global expression QTL (eQTL) mapping from hypothalamus tissue, as well as causality analysis. This identified five candidate genes, with the genes PRDX4 and ACOT9 emerging as the best supported candidates. In addition, we also investigated the connection between tonic immobility, meat pH and struggling behaviour, as the two candidate genes PRDX4 and ACOT9 have previously been implicated in controlling muscle pH at slaughter. We did not find any phenotypic correlations between tonic immobility, struggling behaviour and muscle pH in a smaller additional cohort, despite these behaviours being repeatable within-test.

Assessing Post-Traumatic Tonic Immobility Responses: The Scale for Tonic Immobility Occurring Post-Trauma

BACKGROUND

Peri-traumatic tonic immobility has been associated with the development and course of post-traumatic stress disorder. Despite serving as an adaptive late-stage defense response, tonic immobility that continues in response to post-traumatic reminders may lead to reduced functioning and a diminished sense of well-being. At present, no validated self-report measures assess post-traumatic tonic immobility responses specifically.

METHODS

The primary objective of the present study was to evaluate the Scale for Tonic immobility Occurring Post-trauma (STOP), the first self-report measure developed to assess for the presence and severity of tonic immobility responses that persist following trauma exposure as part of post-traumatic symptomatology. Trauma-exposed clinical and non-clinical participants (N = 462) with a history of tonic immobility completed a demographic questionnaire, the STOP, and measures of post-traumatic symptoms, dissociation, anxiety, and depression.

RESULTS

STOP assessed four latent constructs, which were interpreted following the human defense cascade model. Together, these factors capture the sensorimotor and perceptual alterations, and dissociative experiences, associated with post-traumatic tonic immobility as a trauma-related altered state. Residual symptoms and the experience of negative affect following this response (including guilt and shame) are also represented. STOP scores demonstrated excellent reliability, as well as good construct and convergent validity, with other measures of dissociation and post-traumatic stress disorder. Results from the present study suggest tonic immobility is most consistent with other dissociative post-traumatic symptomatology.

CONCLUSIONS

STOP demonstrates excellent preliminary psychometric properties and may be useful for researchers and clinicians wishing to assess chronic forms of tonic immobility across trauma-exposed, clinical and community samples.

Behavioural Type Affects Space Use in a Wild Population of Crows (Corvus corone)

While personality‐dependent dispersal is well studied, local space use has received surprisingly little attention in this context, despite the multiple consequences on survival and fitness. Regarding the coping style of individuals, recent studies on personality‐dependent space use within a habitat indicate that ‘proactive’ individuals are wider ranging than ‘reactive’ ones. However, such studies are still scarce and cover limited taxonomic diversity, and thus, more research is needed to explore whether this pattern generalises across species. We examined the link between coping style and space use in a population of crows (Corvus corone) freely inhabiting the urban zoo of Vienna, Austria. We used a binary docility rating (struggle during handling vs. no struggle) and a tonic immobility test to quantify individual coping style. Individual space use was quantified as the number of different sites at which each crow was observed, and we controlled for different number of sightings per individual by creating a space use index. Only the binary docility rating showed repeatability over time, and significantly predicted space use. In contrast to previous studies, we found that reactive crows (no struggle during handling) showed wider ranging space use within the study site than proactive individuals (who struggled during handling). The discrepancy from previous results suggests that the relationship between behavioural type and space use may vary between species, potentially reflecting differences in socioecology.

Antioxidants safeguard telomeres in bold chicks

Telomeres are sensitive to damage induced by oxidative stress, and thus it is expected that dietary antioxidants may support the maintenance of telomere length in animals, particularly those with a fast rate of life (e.g. fast metabolism, activity and growth). We tested experimentally the effect of antioxidant supplements on telomere length during early development in wild gull chicks with natural individual variations in behaviour pattern and growth rate. Proactive chicks had shorter telomeres than reactive chicks, but the penalty for the bold behaviour pattern was reduced by antioxidant supplementation. Chicks growing faster had longer telomeres during early growth, suggesting that inherited quality supports a fast life history.

Effects of Dark Brooders on Behavior and Fearfulness in Layers

Chicks require heat to maintain body temperature during the first weeks after hatch. This may be provided by dark brooders; i.e. , horizontal heating elements equipped with curtains. The objective was to test effects of rearing layer chicks with dark brooders on time budget and fearfulness. Behavioral observations were performed during the first six weeks of age. Three different fear tests were conducted when the birds were age 3-6, 14-15 and 26-28 weeks. During the first four days, brooder chicks rested more than control chicks whereas they spent less time drinking, feather pecking and on locomotion ( p ≤ 0.009). On days 16, 23, 30 and 42, brooder chicks spent less time on feather pecking, locomotion and fleeing ( p ≤ 0.01) whereas foraging and dust bathing occurred more often on day 42 ( p ≤ 0.032). Brooder birds had shorter durations of tonic immobility at all ages ( p = 0.0032), moved closer to the novel object at age 15 weeks ( p < 0.0001), and had shorter latencies to initiate locomotion in the open-field test at age 28 weeks ( p < 0.0001). Results support the suggestion that dark brooders can be a successful method of reducing or preventing fear and feather pecking in layers.

Personality over ontogeny in zebra finches: long-term repeatable traits but unstable behavioural syndromes

A crucial assumption of animal personality research is that behaviour is consistent over time, showing a high repeatability within individuals. This assumption is often made, sometimes tested using short time intervals between behavioural tests, but rarely thoroughly investigated across long time intervals crossing different stages of ontogeny. We performed such a longitudinal test across three life stages in zebra finches (Taeniopygia guttata), representing about 15-20% of their life span in captivity, and found repeatabilities ranging from 0.03 to 0.67. Fearlessness and exploration were the most repeatable traits both within and across life stages. Activity and aggression were repeatable across, but not or only partly within life stages. Boldness was not repeatable. Furthermore, we found no evidence for a consistent behavioural syndrome structure across ontogeny. Our results indicate that the consistency of behavioural traits and their correlations might be overestimated and suggest that life-long stability of animal personality should not simply be assumed.

The influence of mitonuclear genetic variation on personality in seed beetles

There is a growing awareness of the influence of mitochondrial genetic variation on life-history phenotypes, particularly via epistatic interactions with nuclear genes. Owing to their direct effect on traits such as metabolic and growth rates, mitonuclear interactions may also affect variation in behavioural types or personalities (i.e. behavioural variation that is consistent within individuals, but differs among individuals). However, this possibility is largely unexplored. We used mitonuclear introgression lines, where three mitochondrial genomes were introgressed into three nuclear genetic backgrounds, to disentangle genetic effects on behavioural variation in a seed beetle. We found within-individual consistency in a suite of activity-related behaviours, providing evidence for variation in personality. Composite measures of overall activity of individuals in behavioural assays were influenced by both nuclear genetic variation and by the interaction between nuclear and mitochondrial genomes. More importantly, the degree of expression of behavioural and life-history phenotypes was correlated and mitonuclear genetic variation affected expression of these concerted phenotypes. These results show that mitonuclear genetic variation affects both behavioural and life-history traits, and they provide novel insights into the maintenance of genetic variation in behaviour and personality.

Fear and the Defense Cascade: Clinical Implications and Management

Evolution has endowed all humans with a continuum of innate, hard-wired, automatically activated defense behaviors, termed the defense cascade. Arousal is the first step in activating the defense cascade; flight or fight is an active defense response for dealing with threat; freezing is a flight-or-fight response put on hold; tonic immobility and collapsed immobility are responses of last resort to inescapable threat, when active defense responses have failed; and quiescent immobility is a state of quiescence that promotes rest and healing. Each of these defense reactions has a distinctive neural pattern mediated by a common neural pathway: activation and inhibition of particular functional components in the amygdala, hypothalamus, periaqueductal gray, and sympathetic and vagal nuclei. Unlike animals, which generally are able to restore their standard mode of functioning once the danger is past, humans often are not, and they may find themselves locked into the same, recurring pattern of response tied in with the original danger or trauma. Understanding the signature patterns of these innate responses--the particular components that combine to yield the given pattern of defense-is important for developing treatment interventions. Effective interventions aim to activate or deactivate one or more components of the signature neural pattern, thereby producing a shift in the neural pattern and, with it, in mind-body state. The process of shifting the neural pattern is the necessary first step in unlocking the patient's trauma response, in breaking the cycle of suffering, and in helping the patient to adapt to, and overcome, past trauma.

Exposure to trauma-relevant pictures is associated with tachycardia in victims who had experienced an intense peritraumatic defensive response: the tonic immobility

Tonic immobility is an involuntary, last-ditch defensive reaction characterized by physical inactivity in a context of inescapable threat that has been described in many species, including humans. The occurrence of this defensive response is a predictor of the severity of psychiatric disorders and may be considered as an index of an intense reaction to a traumatic event. Here, we investigated whether the retrospective reports of peritraumatic tonic immobility reaction in participants exposed to a traumatic event would modify their cardiac responses to pictures related to their trauma. Using a questionnaire of life-threating events, we selected students who experienced violent crime as their most intense trauma and students who had never experienced a violent crime trauma, but experienced other traumatic events. All participants completed a questionnaire that estimated the intensity of tonic immobility during their most intense trauma. Electrocardiographic recordings were collected during exposure to pictures. Participants viewed emotional pictures (human attack with guns) and neutral pictures. These emotional stimuli were selected to be trauma-relevant to the violent crime group and non trauma-relevant to the no violent crime trauma group. Violent crime group showed a positive correlation between heart rate changes after viewing trauma-related pictures and tonic immobility scores. We observed that low tonic immobility scores were associated with bradycardia and high scores with tachycardia in response to trauma-relevant pictures. For the no violent crime group, no significant correlation was detected. These results suggest that the relevance of the stimuli and the magnitude of the defensive response during a previous trauma event were important factors triggering more intense defensive responses.

Comparative proteomic analysis of the breast muscle response to chronic corticosterone administration in broiler chickens showing long or short tonic immobility

Broilers of the same genetic origin were classified as short or long tonic immobility duration (STI and LTI, respectively) phenotypes and treated chronically with vehicle (control) or corticosterone (CORT) dissolved in drinking water between 27 and 42 d of age. Differential expression of proteins and mRNA was examined using 2-dimensional gel electrophoresis and real-time PCR to elucidate the mechanism behind the severe retardation of broiler breast muscle growth caused by LTI and CORT. The majority of the 13 proteins found to be differentially expressed in breast muscle of STI and LTI broilers are involved in either glycolysis (5 proteins) or myofilament formation (5 proteins). Of the 16 proteins differentially expressed in breast muscle following CORT treatment, 6 are structural proteins, 5 are categorized as cellular defense and stress proteins, and 3 (pyruvate kinase, l-lactate dehydrogenase, and creatine kinase) are involved in responses to stress and muscle damage. Real-time PCR results indicated that expression of these proteins is transcriptionally and posttranscriptionally regulated. Protein synthesis capacity, estimated by the RNA-to-protein ratio, was significantly lower in the breast muscle of CORT-treated broilers than in untreated control broilers. The level of Leu, Gly, and Ser in serum was significantly higher in CORT-treated broilers than in the control birds. Therefore, we conclude that CORT treatment retards the growth of skeletal muscle by suppressing protein synthesis and augmenting protein catabolism, paralleling the response to severe stress and muscle damage, and the negative effect of LTI on muscle growth is likely mediated through glucose metabolism. No interaction was observed between CORT and tonic immobility affecting growth performance or any parameter examined in the current study.

Effects of tonic immobility (TI) and corticosterone (CORT) on energy status and protein metabolism in pectoralis major muscle of broiler chickens

Tonic immobility (TI), which can be divided into short (STI) or long (LTI) duration, is a character related to fear. Our previous study has demonstrated LTI phenotype and chronic corticosterone (CORT) administration retarded growth of breast muscle in broiler chickens. In order to investigate the mechanism behind the negative effects of LTI and CORT on growth, the level of mRNA transcription of several key genes linked to energy and protein metabolism was measured in muscle. LTI broilers showed lower levels of ATP, energy charge (EC) (p<0.01), and lower muscle glycogen content (p<0.05) but higher level of ADP (p = 0.08) than STI birds. CORT treatment elevated EC level (p<0.05) and reduced liver glycogen content (p<0.05). Real-time PCR results showed that STI chickens had higher mRNA expression of PPAR α (p = 0.06) and AMPK α (p = 0.09) than LTI. CORT significantly down-regulated α-enolase mRNA expression in breast muscle compared to control (p<0.05). Neither TI nor CORT altered gene expression in Akt/mTOR/p70s6k cascade pathway in muscle (p > 0.05). However, western blot results showed that LTI chickens exhibited higher protein content of total Akt (p = 0.05) and phosphorylated Akt (p = 0.06) than STI. CORT treatment decreased the total protein content of Akt (p = 0.09) and p70s6k (p = 0.08). These results suggest that the retardation of muscle growth by LTI and chronic CORT administration parallels a strong alternation in energy status but slight changes of Akt/mTOR/p70s6k cascade, indicating that a decrease in muscle growth induced by LTI and CORT might not be mediated through mTOR-dependent signaling pathways.

Differences in responses to repeated fear-relevant stimuli between Nagoya and White Leghorn chicks

Freezing responses to fearful stimuli are crucial for survival among all animal species within a prey-predator system. Generally, the degree of fearfulness correlates with intensity, duration, and frequency of freezing behaviours in response to fear-relevant stimuli. The present study examines innate fear responses to human handling in 144 newly hatched chicks through a tonic immobility (TI) test. Two fear responses-freezing duration and number of TI inductions-were examined. Individual variations in innate fear were investigated in chicks 1-2 days post-hatching when the restraint procedure was successively repeated 3 times within each day. Chicks showed sensitivity to fearful stimuli and considerable inter-individual variation in freezing duration and number of attempts required to induce TI. Moreover, differences were observed between breeds; White Leghorn chicks showed relatively low fear levels with gradual increases in TI duration, whereas Nagoya chicks showed extended TI duration and habituation to fearful stimuli. Our results suggest that TI reactions among newly hatched chicks are an innately determined behaviour specific to a breed or strain of chicken. Further, fearful responses among newborn chicks are not simple, but complex behaviours that involve multiple factors, such as breed-specific contextual fear learning and habituation/sensitisation processes.