Behavioral Indicators Of Stress Research Articles

The behavioral effects of walking on a collar and harness in domestic dogs (Canis familiaris)

Dogs are a popular pet in the United Kingdom, and walking a dog is widely recognized as an important part of dog ownership. A number of different restraints can be used when walking dogs on leashes, such as collars and harnesses. Previous research has examined the behavioral effects of walking dogs on head and neck collars. Harnesses are often anecdotally proposed to be more beneficial to dog welfare than other alternative restraints; however, to date, the effects of walking dogs on harnesses have not been investigated. The aim of this study was to determine the behavioral responses of dogs walked on neck collars or harnesses. The broader purpose of this study was to examine if the type of restraint worn causes stress in dogs. To explore this, a within-subject counterbalanced design was used. Thirty privately owned dogs were recruited within 2 groups (each group: n = 15); those previously walked on a harness and those previously walked on a neck collar. Dogs were walked for 20 minutes each while behavioral indicators of stress were recorded. After this trial, owners were given the alternative walking restraint and returned a week later to perform a second 20-minute walk. Behavioral indicators were again recorded. No significant differences were found between behaviors shown by dogs when walked on either collar or harness. However, dogs with a history of being walked on a collar showed increased low ear position. This may suggest that these dogs are more stressed; however, because of the lack of support from the other stress indicators, motivations, such as indicating appeasement toward their owners, should also be considered. These findings suggest that, at least for the specific harness and collar trialed, neither neck collars nor harnesses are eliciting stress in dogs. However, future research determining the long-term effects of neck collar and harness use would be beneficial.

Into the pressure cooker: Student stress in college preparatory high schools

PurposeThe goals of this study were to (1) measure psychological, physiological, and behavioral indicators of stress, (2) assess the relationship between stress and student attitudes, and (3) explore coping behaviors in response to stress, among a sample of students in two academically high-achieving environments. MethodThree hundred thirty-three students in grades 9 through 12 from two college-preparatory high schools completed a cross-sectional online survey that included the Students' Life Satisfaction Scale, School Attitude Assessment Questionnaire-Revised, and assessments for stress-related indicators, including eating, sleeping and exercise, and strategies they utilized for coping with stress. ResultsStudents reported a high prevalence of physical and psychological correlates of stress, and related unhealthy behaviors such as widespread and chronic sleep deprivation and rushed meals. ConclusionsThe results suggest areas to focus attention for identifying and addressing maladaptive responses to stress among high-achieving student populations.

Stereotypic behaviours in Melopsittacus undulatus: Behavioural consequences of social and spatial limitations

The demand for parrots for pet and scientific purposes is an increasing phenomenon. Yet, the cognitive complexity of these animals makes it difficult to fully satisfy their eco-ethological needs in captivity, and strategies commonly adopted for their husbandry are often unsuccessful in guaranteeing their wellbeing. In this study, we investigated the effects of environmental restrictions on the behavioural repertoire of budgerigars, the most common parrot in captivity. Specifically, stereotypies and other behavioural indicators of stress were analyzed with respect to social and spatial housing conditions, that is, the number of individuals per housing unit and the size of the cages. In the first experiment, we compared the behavioural response of budgerigars maintained in three different housing conditions and we observed that levels of stereotypic and non-stereotypic behaviours increased from mild to severe captive restrictions. We also found that this response varied between males and females. In the second experiment, we investigated the behavioural repertoire of budgerigars when rearranged in their housing units. We observed that some of the previously observed stereotypic behaviours were significantly reduced soon after individuals were allowed to interact with multiple social partners.

Behavioural and physiological indicators of shelter dogs' welfare: Reflections on the no-kill policy on free-ranging dogs in Italy revisited on the basis of 15 years of implementation

The Italian National Law 281 of 1991 forbids the euthanatization of free-ranging dogs, unless they have an incurable illness or are proved to be dangerous. Without neglecting the undeniable benefits of the “no-kill” policy, nevertheless it has brought about a chronic overpopulation in shelters and, as a result, higher costs of management and welfare problems since some dogs remain in the shelter for life. In 2004–2008, the Istituto Zooprofilattico Sperimentale of the Lazio and Tuscany regions carried out a survey in the Lazio Region to verify the effects of the Italian National Law 281/91 on free-ranging dog management following 15years from its implementation. One of the aims of the study was an assessment of the welfare of dogs in a shelter sample (8 shelters out of 47 censused in the Lazio Region). 97 mixed-breed dogs were selected, their behaviour was studied and a blood sample was taken for each dog in order to determine the individual blood concentration of cortisol and the amount of oxidative damage (level of dRoms), as well as the amount of antioxidants to cope with it. Moreover, the total leukocyte count (leukogram) was accomplished. We ran general backward stepwise regression models using “level of antioxidant”, “level of dRoms” and “level of serum cortisol” as dependent variables respectively. The results showed that the most important variable that improved the level of welfare of dogs consisted in having the opportunity to regularly go out of the cage for a walk, whereas other variables like gender, size of the cage (small, medium, large), being alone in the cage, and being neutered/entire, had no significant effect on the physiological indicators of welfare. Dogs that enjoyed the regular walk had a higher total antioxidant capacity, and performed a lower frequency of displacing activities and stereotyped behaviour. Moreover, oxidative stress parameters seem to be indicators well matched with behavioural indicators of stress. Thus, for the first time, markers of oxidative status are utilised for the welfare evaluation in the domestic dog. Furthermore, the results of this paper give some suggestion about how small steps can help to improve shelters and, furthermore, this paper intends to solicit the debate on the no-kill policy.

The Effect of Fission–Fusion Zoo Housing on Hormonal and Behavioral Indicators of Stress in Bornean Orangutans (Pongo pygmaeus)

The welfare of captive animals could be improved if zoos were to place more emphasis on their species-specific needs. In the wild, orangutans live in a fission–fusion social system and have a semisolitary lifestyle. However, most zoos keep orangutans in permanent groups, which may be stressful for them. Apenheul Primate Park in Apeldoorn, Netherlands, houses 14 Bornean orangutans in a simulated fission–fusion social system. To assess how this housing system affects indicators of stress, we measured fecal glucocorticoid metabolites (fGCM) and determined proportions of self-directed behavior (scratching and autogrooming). We compared fGCM concentrations of the Apenheul animals to those of zoo orangutans kept in permanent groups. In addition, we tested the effect of group size, visitor number, sex, age, and change of group composition on fGCM concentrations and proportions of self-directed behavior in the Apenheul orangutans. In contrast to Bornean orangutans housed in permanent groups, we did not find a group size effect on fGCM or on self-directed behavior in Apenheul’s fission–fusion housing system. In addition, fGCM concentrations in Apenheul orangutans increased significantly with visitor numbers. Visitor number also affected proportions of self-directed behavior, and mean proportions of scratching were positively correlated with mean values of fGCM concentrations. Although these results suggest that the fission–fusion housing system in Apenheul reduces the group size effect leading to social stress in Bornean orangutans, they also show that visitors are an important factor that needs to be mitigated if the well-being of captive primates and other zoo animals is to be improved.

Effects of social housing on hippocampal dendrites and behavior in ovariectomized rats

Social stress is both species and gender specific. For female rats, individual housing and social instability housing conditions are associated with behavioral indicators of stress and depression. The present study directly compared the effects of six weeks of individual housing, social instability and mixed sex, semi-crowded housing in a visible burrow system (VBS) on ovariectomized female rats. Paired, stable housing was used as the control. Behavioral tests were conducted two, four and six weeks into the housing manipulations and included sucrose consumption, social interest, and activity in the open field. Following a series of four behavioral tests, animals were sacrificed and brains were processed for Golgi impregnation. Basal dendrites of CA3 hippocampal neurons were measured. Results indicate that the individual housing and social instability groups were comparable to the control group for all measures. In contrast, the rats housed in the VBS exhibited reduced activity in open field testing, and alterations in social interest. Dendritic lengths were also reduced in those animals living in the VBS in comparison to the animals housed in pairs. To our knowledge, this is the first report of behavioral and neural effects of VBS housing on female rats. Further research is necessary to determine what facets of the VBS housing are responsible for the behavioral and neural changes. This article is part of a Special Issue entitled 'Animal Models'.

The study of the behavior of domestic animals: From aristotle through darwin to today

Over the past 50 years, biomedical research has established a strong linkage between psychosocial stress and disease risk in humans, which has transformed the understanding of stress and the role it plays in human lives. This research has led to personalized medicine where a reduction in daily life stress is a main goal for many people with debilitating illnesses. This review describes the supporting evidence that social stress also plays a critical role in farm animal disease prevention, and may be a mediator by which common management practices can increase disease risk.There is evidence that social factors, including deprivation of social contact (‘social isolation’), reducing space allowance (‘crowding’) and disturbing social order (‘social instability’) trigger physiological and behavioral indicators of stress in livestock. Less research exists, however, linking management practices that trigger social stress with higher disease risk. Suggestions are offered for future research opportunities, and practical, evidence-based recommendations are made for reducing the negative effects of social isolation, instability and crowding. The current evidence that social factors contribute to disease risk in farm animals is not as convincing as the human literature, but remains a promising and important area for future research.

A novel scale of behavioural indicators of stress for use with domestic horses

Behaviour scores (BS) offer non-invasive, objective and easy to use ways of assessing welfare in animals. Their development has, however, largely focused on behavioural reactions to stressful events (often induced), and little use of physiological measures has been made to underpin and validate the behavioural measures. This study aimed to develop a physiologically validated scale of behavioural indicators of stress for the purpose of welfare assessment in stabled domestic horses. To achieve this, behavioural and physiological data were collected from 32 horses that underwent routine husbandry procedures. Principal component analysis (PCA) of the behavioural and physiological data revealed three meaningful components that were used as the basis of the scale. Analysis of video clips of the horses’ responses to the husbandry procedures was undertaken by a panel of equestrian industry professionals using a free choice profiling (FCP) methodology. These results were added to the scale along with key definitions from relevant literature. Salivary cortisol levels were significantly correlated with the BS confirming the scale was meaningful and reflected physiological stress. The scale offers an easy to use ‘tool’ for rapid, reliable non-invasive welfare assessment in horses, and reduces the need for potentially invasive physiological measures.

The effects of repeated oral gavage on the health of male CD-1 mice

Oral gavage is a widely used method for administering substances to animals in pharmacological and toxicological studies. The authors evaluated whether oral gavage causes behavioral indicators of stress, increased mortality rate, alterations in food and water consumption and body weight or histological lesions in CD-1 mice. Gavage was carried out once per d for 5 d per week over 6 consecutive weeks. The mortality rate of mice in this study was 15%. Mice subjected to gavage did not undergo changes in food or water consumption during the study, and their mean body weights and relative organ weights were similar to those of mice in the control group. Serum cortisol levels at the time of euthanasia in mice in both groups were within the normal range. Histopathology showed acute esophagitis and pleurisy, indicative of perforation of the esophagus, in the two mice that died but no abnormalities in the other mice. The results suggest that animal stress and mortality related to oral gavage can be minimized when the procedure is carried out by an experienced technician.

Perception of dogs’ stress by their owners

Abstract Questionnaires potentially have a broad applicability in measuring stress levels in dogs, as owners know their dogs' behavior and personality better than anyone else. The aim of this research was to evaluate how owners perceive stress in their dogs through understanding of displayed behaviors. The survey was carried out using 1,190 questionnaires completed by dog owners. More than half of respondents were able to correctly identify stress as a short- or long-term alteration of the psychophysical equilibrium that can develop into illness. This ability was higher with higher educational levels. The behavioral indicators of stress most frequently identified by owners were trembling and whining, followed by aggressiveness, excessive barking, and panting. More subtle behaviors such as looking elsewhere, turning head, yawning, and nose licking were more rarely reported, suggesting that few owners are able to correctly interpret and intervene in early stages of stress. The vast majority of respondents indicated that dogs were stressed seldom or only in specific situations. Men generally considered their dogs as experiencing low stress more often than did women, whereas women considered their dogs as being moderately stressed more often than did men. An owner's ability to recognize behavioral signs of stress is important, as it enables the owner to help the animal to avoid welfare problems, such as stressful situations, and favors a rapid recovery of psychophysical homeostasis by interrupting the progression to overstress and distress. The results show that some owners can help in protecting the welfare of their dogs, but that many owners would benefit from educational efforts to improve their ability to interpret their dogs' behavior.

Acoustic features to arousal and identity in disturbance calls of tree shrews ( Tupaia belangeri)

Across mammalian species, comparable morphological and physiological constraints in the production of airborne vocalisations are suggested to lead to commonalities in the vocal conveyance of acoustic features to specific attributes of callers, such as arousal and individual identity. To explore this hypothesis we examined intra- and interindividual acoustic variation in chatter calls of tree shrews ( Tupaia belangeri). The calls were induced experimentally by a disturbance paradigm and related to two defined arousal states of a subject. The arousal state of an animal was primarily operationalised by the habituation of the subject to a new environment and additionally determined by behavioural indicators of stress in tree shrews (tail-position and piloerection). We investigated whether the arousal state and indexical features of the caller, namely individual identity and sex, are conveyed acoustically. Frame-by-frame videographic and multiparametric sound analyses revealed that arousal and identity, but not sex of a caller reliably predicted spectral–temporal variation in sound structure. Furthermore, there was no effect of age or body weight on individual-specific acoustic features. Similar results in another call type of tree shrews and comparable findings in other mammalian lineages provide evidence that comparable physiological and morphological constraints in the production of airborne vocalisations across mammals lead to commonalities in acoustic features conveying arousal and identity, respectively.

Efficacy of dog appeasing pheromone in reducing stress and fear related behaviour in shelter dogs

The behavioural effects of dog appeasing pheromone (DAP) continuously administered over a 7-day period, were evaluated in adult dogs housed in a public animal shelter. Barking amplitude (dB) and the frequency of discrete behavioural responses to two temperament tests associated with fear, separation and excitable behaviour (Arrowsmith, unpublished data) were recorded in 37 treatment and 17 control dogs. Mean barking amplitude ( L eq) and barking frequency were significantly reduced in dogs subject to DAP exposure for 7 days ( P < 0.001, <0.04, respectively), though peak values ( L peak) were not significantly altered. There was also some reduction in the barking amplitude of dogs during the 1 min recovery period, following a distraction. Following 7 days of DAP exposure, there were significant differences in resting ( P = 0.03), barking ( P < 0.04) and sniffing frequency ( P = 0.01) in response to a friendly stranger. There were no highly significant differences in response to a neutral stranger. The preliminary tests indicate that DAP is a useful palliative tool for reducing some behavioural indicators of stress in dogs. Further tests are necessary to investigate the use of DAP in canine stress reduction in conjunction with traditional behavioural therapy programmes.

Reproductive traits of female rabbits as affected by heat stress and lighting regime under subtropical conditions of Egypt

AbstractThe present work was planned to study the effects of different lighting regimes in both mild and hot periods of the year on New Zealand White doe rabbit traits. The light regimes used were natural daylight as control, 16 h light and 8 h darkness, 12 h light and 12 h darkness, and 8 h light and 16 h darkness. The traits studied were thermoregulatory parameters (respiration rate and temperatures of ear, rectum and skin), type of mating necessary, conception rate, gestation period, fur plucking, behavioural indicators of stress, litter size, litter weight, kit body weight, kit daily gain in weight, milk yield, kit milk intake, efficiency of conversion of milk into live-weight gain and kit mortality, at weekly intervals between birth and weaning at 35 days. Estimation of temperature-humidity index indicated that the doe rabbits were exposed to very severe heat stress, during the hot period of the year. Period of the year (heat stress) affected adversely many of the doe traits studied. The effects were significant (P &lt; 0·001, 0·01 or 0·05) on thermoregulatory parameters (respiration rate and temperatures of ear, rectum and skin), litter weight at days 21 and 28 of age, kit body weight at birth, milk yield of the doe at day 7 of suckling and milk intake per kit at 7 and 14 days of age. Exposure of doe rabbits to a long daylight regime affected adversely many of the traits studied, while the contrary occurred with short daylight. The effects were significant (P &lt; 0·001, 0·01 or 0·05) on litter size at all ages except at birth, litter weight at 14, 21 and 28 days of age, milk yield on all days studied, efficiency of conversion of milk into live-weight gain at days 7, 21 and 28 and mortality at birth and pre-weaning. There was no significant interaction between period of the year and light regime on any of the traits examined. Therefore, only the main factors are reported.

Behavioral Evidence for the Cutaneous Expression Of Emotion in a Chimpanzee (Pan Troglodytes)

AbstractSelf-directed behaviors (SDBs) are behavioral indicators of stress, but have received relatively little experimental scrutiny. The present study reports the distribution of SDBs in a 14-year-old male chimpanzee in relation to performance on a matching-to-sample task of varying difficulty. The rate of rubbing behaviors (self-touching with the hand without any raking motion of the fingernails) was positively correlated with performance, whereas scratching rates were negatively correlated with performance. SDBs were displayed predominantly with the left hand during sessions of high performance (low task difficulty), with a shift toward the right hand during sessions of low performance (high task difficulty). SDBs were exhibited relatively more with the right hand after incorrect responses (and secondary negative reinforcer) than after correct responses (and secondary positive reinforcer). Rubs directed to the face were displayed relatively more often to the right side after incorrect responses, compared to rubs displayed after correct responses, whereas scratching was directed relatively more often to the left side of the body after incorrect responses, compared to scratching displayed after correct responses. Rough scratching was displayed more quickly after auditory feedback on performance than were rubs or gentle scratches. Rubs were directed more to the face (trigeminal) and scratches more to the body (spinothalamic). Taken together, these results suggest that there may be asymmetrical central nervous system processing of negative emotion by chimpanzees during cognitive tasks.

Cat Housing in Rescue Shelters: A Welfare Comparison Between Communal and Discrete-Unit Housing

AbstractCats living long-term (over one month) in shelters were assessed for behavioural indicators of stress, using a stress scoring method in combination with behavioural observation. It is hypothesised that because of the inappropriate social grouping of unrelated adult cats and group instability, communal housing creates more stress than discrete-unit housing. Seventy-two cats were observed: 36 were housed communally with unfamiliar conspecifics, and 36 were housed in discrete units, either alone or with other previously familiar conspecifics. The mean stress score was greater in communal housing than in discrete-unit housing. Stress scores range from 1 to 7, with 1 indicating no stress experienced, and 7 indicating extreme stress. Individual scores showed that cats in discrete units, in comparison to those in communal housing, gained a significantly higher percentage of observations in the score 2 category, indicating that no stress was being experienced. Cats in communal housing gained a significantly higher percentage in the score 4 category (stressed). Score 5 was found exclusively in communal housing, but only in 2% of instances. Extreme stress was not found in cats housed under either condition. Cats in the different types of housing differed in their frequencies of hiding, play, sleeping/resting in close contact with one another, and agonistic behaviour. There was no difference between housing types in frequency of eating, drinking, grooming, and toilet use. In this study, cats housed communally experienced moderately higher levels of stress than cats housed in discrete units. Further research is recommended to determine the effect on stress levels of longer shelter residence time and of changes in group size and/or density.

Acute Stress Hyperglycemia in Cats Is Associated with Struggling and Increased Concentrations of Lactate and Norepinephrine

We characterized the changes in blood glucose concentrations in healthy cats exposed to a short stressor and determined the associations between glucose concentrations, behavioral indicators of stress, and blood variables implicated in stress hyperglycemia (plasma glucose, lactate, insulin, glucagon, cortisol, epinephrine, and norepinephrine concentrations). Twenty healthy adult cats with normal glucose tolerance had a 5‐minute spray bath. Struggling and vocalization were the most frequent behavioral responses. There was a strong relationship between struggling and concentrations of glucose and lactate. Glucose and lactate concentrations increased rapidly and significantly in all cats in response to bathing, with peak concentrations occurring at the end of the bath (glucose baseline 83 mg/dL, mean peak 162 mg/dL; lactate baseline 6.3 mg/dL, mean peak 64.0 mg/dL). Glucose response resolved within 90 minutes in 12 of the 20 cats. Changes in mean glucose concentrations were strongly correlated with changes in mean lactate (r= .84;P&lt;.001) and mean norepinephrine concentrations (r= .81;P&lt; .001). There was no significant correlation between changes in mean glucose concentrations and changes in mean insulin, glucagon, cortisol, or epinephrine concentrations. Struggling and lactate concentrations were predictive of hyperglycemia. Gluconeogenesis stimulated by lactate release is the likely mechanism for hyperglycemia in healthy cats in this model of acute stress. Careful handling techniques that minimize struggling associated with blood collection may reduce the incidence of stress hyperglycemia in cats.

Acute stress hyperglycemia in cats is associated with struggling and increased concentrations of lactate and norepinephrine.

We characterized the changes in blood glucose concentrations in healthy cats exposed to a short stressor and determined the associations between glucose concentrations, behavioral indicators of stress, and blood variables implicated in stress hyperglycemia (plasma glucose, lactate, insulin, glucagon, cortisol, epinephrine, and norepinephrine concentrations). Twenty healthy adult cats with normal glucose tolerance had a 5-minute spray bath. Struggling and vocalization were the most frequent behavioral responses. There was a strong relationship between struggling and concentrations of glucose and lactate. Glucose and lactate concentrations increased rapidly and significantly in all cats in response to bathing, with peak concentrations occurring at the end of the bath (glucose baseline 83 mg/dL, mean peak 162 mg/dL; lactate baseline 6.3 mg/dL, mean peak 64.0 mg/dL). Glucose response resolved within 90 minutes in 12 of the 20 cats. Changes in mean glucose concentrations were strongly correlated with changes in mean lactate (r = .84; P < .001) and mean norepinephrine concentrations (r = .81; P < .001). There was no significant correlation between changes in mean glucose concentrations and changes in mean insulin, glucagon, cortisol, or epinephrine concentrations. Struggling and lactate concentrations were predictive of hyperglycemia. Gluconeogenesis stimulated by lactate release is the likely mechanism for hyperglycemia in healthy cats in this model of acute stress. Careful handling techniques that minimize struggling associated with blood collection may reduce the incidence of stress hyperglycemia in cats.

Dissociation of cortisol and behavioral indicators of stress in an orangutan (Pongo pygmaeus) during a computerized task

Computerized testing can induce behavioral signs of frustration in apes. Three variations of a computer task were used to investigate the effects of inter-trial intervals and rate of cursor movement on frustrative behavior and cortisol in an orangutan. Behaviors were recorded during test sessions, and saliva was collected immediately after test sessions for cortisol assay. Behavioral results indicated that extended (20 sec) periods of delay between trials induced signs of frustration in the subject, including forceful manual manipulation of objects and self-scratching. However, cortisol results indicated that Hypothalamic-Pituitary-Adrenal (HPA) axis activity was not induced by task performance. Rather, cortisol levels were reduced during performance of computer tasks compared to baseline levels. Findings from this study suggest that behavioral and cortisol responses to stress induced by performance of computer testing can become dissociated. This study validates salivary cortisol as a measure of HPA activity in apes and demonstrates a normal circadian rhythm of cortisol release in an orangutan.

Alternative housing for sows and litters: 1. Effects of sow-controlled housing on responses to weaning

We examined whether a sow-controlled housing system would ameliorate production and welfare problems resulting from the abrupt separation of piglets from sows at weaning. Forty-four sows and litters were housed during lactation in either a `confined' pen where the sow and litter were kept together, or a `get-away' pen where the sow could leave the litter by stepping over a barrier. Sows in get-away pens varied greatly in the amount of time they spent away from their piglets and were classified as `Early Leavers' if they spent more than 60% of their time away by the third week of lactation or `Late Leavers' if they did not. Body weight changes and food consumption of piglets were measured for 2 weeks after separation from the sow at 5 weeks post-partum. As a possible indicator of stress at weaning, sows and litters were tested for spontaneous behaviour and response to the playback of calls upon separation. Overall, piglets from get-away pens gained 27% more weight and consumed 31% more food after weaning than piglets from confined pens. Piglets from Early Leaver sows showed a non-significant tendency to gain more weight and consume more solid food than piglets from Late Leaver sows. Pre-separation accommodation and sow classification (Early versus Late Leavers) had a limited effect on post-separation piglet behaviour. Piglets from get-away pens were more active and bit pen-mates more after separation than piglets from confined pens. This was primarily due to the behaviour of piglets from Early Leaver sows which were more active and had a non-significant tendency to bite more than piglets from Late Leaver sows. However, accommodation treatment and sow classification had no clear effect on other spontaneous activity, vocalizations, rooting, or belly-nosing behaviour. Piglets responded to the playback of sow calls by orienting and moving toward the speaker and `freezing', but there was no effect of accommodation type or sow classification on these behaviours. Sows in get-away pens responded to removal of piglets by crossing the barrier and vocalizing more frequently. Playback of piglet vocalizations induced more movement, vocalizations and approaches to the speaker. Overall, accommodation treatment did not result in significant differences in movements or vocalizations in the post-separation period. However, Early Leavers moved and vocalized less frequently than Late Leavers. Thus, sow-controlled housing improves piglet food consumption and weight gain after weaning, but there is only slight evidence of an effect on behavioural indicators of stress for either the piglets or sows.

Beta-Adrenoceptor Blockade and Open-Field Behavior in Male Golden Hamsters

Open-field behavior was compared between untreated, saline-treated, and butoxamine (a beta-2-adrenoceptor antagonist) treated (15 and 5 mg/kg body weight) male golden hamsters ( Mesocricetus auratus). Butoxamine-treated males spent significantly more time self-grooming than saline-treated and untreated males. Especially, untreated males and very similar saline control males showed a clear time sequential structure of behavior with two axes: a grooming-grooming sequence and a highly organized flankmark followed by scrape axis. The degree of this organization was markedly decreased in the butoxamine-treated males, showing an increase in organization of the transition between grooming acts. In general, these males displayed a more stereotypic pattern of behavior than the other. To reveal a systematic relation between the flankmark-scrape response and the exposition to butoxamine and to keep the numbers of experimental animals low, mixed samples were created through consecutive summing of the individual transition matrices of six males treated with 5 mg/kg b.wt. butoxamine to the 15 mg/kg b.wt. sample. By analyzing all samples separately, a positive linear relation between the number of low dosed males in the samples and the degree of organization of the flankmark-scrape sequence was found. The results suggest that the analysis of the transitional structure of behavior during short-term challenges can considerably contribute to an estimation of the coping style and seems to be a more sensitive method than comparing frequencies of behavioral indicators of stress.