Effects of service dogs on children with ASD's symptoms and parents' well-being: On the importance of considering those effects with a more systemic perspective

The integration of a service dog can have numerous benefits for children with Autism Spectrum Disorder (ASD). However, although integration takes place within a family, little is known about the dynamics of these benefits on the family microsystem. Thus, the aim of our study was to propose a more systemic perspective, not only by investigating the benefits of SD integration, but also by exploring the relationships between improvements in children with ASD, parents' well-being, parenting strategies and the quality of the child-dog relationship. Twenty parent-child with ASD dyads were followed before, as well as 3 and 6 months after service dog integration. At each stage, parents completed an online survey which included: the Autism Behavior Inventory (ABI-S), the State-Trait Anxiety Inventory (STAI-Y), the Parenting Stress Index Short Version (PSI-SF), the Monash Dog Owner Relationship Scale (MDORS) and the Parenting Styles and Dimensions Questionnaire (PSDQ). First, repeated measure one-way ANOVAs revealed that both children's ASD symptoms and parents' anxiety decreased significantly after service dog integration. Additionally, Spearman correlations revealed that the more ASD symptoms decreased, the more parent's anxiety and parenting stress also decreased. Second, the quality of the child-dog relationship appeared to contribute to those benefits on both children's ASD symptoms and parents' well-being. Interestingly, parenting strategies seemed to adapt according to these benefits and to the quality of the child-dog relationship. Through a more systemic perspective, this study highlighted that the integration of a service dog involved reciprocal and dynamic effects for children with ASD and their parents, and shed new light on the processes that may underlie the effects of a service dog for children with ASD.

Facial Reactivity to Emotional Stimuli is Related to Empathic Concern, Empathic Distress, and Depressive Symptoms in Social Work Students

Helping professionals are exposed daily to the emotional burden of their vulnerable clients and are at risk of unconscious emotional contagion that may lead to stress and emotional distress. Being aware of their own susceptibility to emotional contagion, however, can improve their well-being. This study aimed to propose an objective measure of emotional contagion, complementary to the Emotional Contagion Scale, and to evaluate its construct and predictive validity. To do so, we turned to FACET, an automatic facial coding software using the Facial Action Coding System, to measure participants' facial expressions as they watched movie clips eliciting specific emotional responses. Results show that both tools to measure emotional contagion (objective and self-reported) are complementary, but they do not measure the same psychosocial constructs. Also, the new objective measure of emotional contagion seems to predict emotional empathy and the risk of developing depressive symptoms among this study's participants.

Emotion Facial Processing in Children With Autism Spectrum Disorder: A Pilot Study of the Impact of Service Dogs

Processing and recognizing facial expressions are key factors in human social interaction. Past research suggests that individuals with autism spectrum disorder (ASD) present difficulties to decode facial expressions. Those difficulties are notably attributed to altered strategies in the visual scanning of expressive faces. Numerous studies have demonstrated the multiple benefits of exposure to pet dogs and service dogs on the interaction skills and psychosocial development of children with ASD. However, no study has investigated if those benefits also extend to the processing of facial expressions. The aim of this study was to investigate if having a service dog had an influence on facial expression processing skills of children with ASD. Two groups of 15 children with ASD, with and without a service dog, were compared using a facial expression recognition computer task while their ocular movements were measured using an eye-tracker. While the two groups did not differ in their accuracy and reaction time, results highlighted that children with ASD owning a service dog directed less attention toward areas that were not relevant to facial expression processing. They also displayed a more differentiated scanning of relevant facial features according to the displayed emotion (i.e., they spent more time on the mouth for joy than for anger, and vice versa for the eyes area). Results from the present study suggest that having a service dog and interacting with it on a daily basis may promote the development of specific visual exploration strategies for the processing of human faces.

Visual Exploration and Observation of Real-Life Interactions Between Children with ASD and Service Dogs

Two original studies explored relationships between visual attention of children with ASD (candidates for receiving a service dog) and their behaviors during their first interaction with a service dog. The first study consisted in video behavioural analyses of 16 children with ASD interacting with a service dog. During the interaction with a service dog, the time children with ASD spent looking towards social items vs objects was associated with how they interacted with the service dog. The second study was exploratory (i.e. 6 children), using the same behavioural approach but coupled with eye-tracking data. The more children with ASD looked at both their parent and the evaluator, as opposed to inanimate items, the more they interacted with the service dog.

Benefit of Practice of the Stroop Test in Young and Older Adults: Pattern of Gain and Impact of Educational Level

Back-Ground/Study Context: The goal of this study was to examine how repeated practice of an inhibition test could improve performance in the test in young and older adults. In particular, we wished to explore whether the gains made during a practice program varied between age groups, and how educational level influenced practice-related gains in older adults. Thus, we tried to disentangle two hypotheses explaining the benefits of practice, namely compensation (greater gain by the lowest performers) and magnification (greater gain by the highest performers).Method: Thirty-three younger adults and 60 older adults were divided into two groups each: (1) Groups in the Practice condition had 10 sessions practicing different versions of Card C of the Stroop Test, (2) groups in the Control condition completed only the pretest and posttest.Results: Overall, results showed that the performance of both young and older adults improved more in the practice condition than in the control condition. The older adults benefited more from practice than the young adults, with earlier and more regular improvement over the 10 sessions. Moreover, the older adults with a higher educational level benefited most.Discussion: These findings seem to support both the compensation and the magnification hypotheses, depending on the variable (age or educational level).

Acute Stress Assessment From Excess Cortisol Secretion: Fundamentals and Perspectives

Our paper aims to redefine the concept of stress in the context of maintaining allostasis; the term has been reserved for situations that concomitantly involve established physiological and psychological stress components. In particular, we analyze how novelty, unpredictability, threat to the ego, and low sense of control challenge allostasis. The concept of stress is then related to a state of difficulty in maintaining allostasis, rather than referring to the overall body response to the situation. This state of difficulty may be observed either in planning the strategy to deal with the situation, evaluating consequent target trajectories for the actuators, the catabolic mediators and the activators, or regulation of the biological systems through these trajectories. Catabolic mediator excesses are proposed as scaling the level of difficulty in maintaining allostasis. The excess proportion of cortisol load (EPCL) is consequently proposed to scale the stress level. A first proof-of-concept of this indicator is realized using the Physiostress dataset, by asserting that it is, as predicted from its theoretical basis, more in phase with the stress level expected from the nature of the task and participant-reported stress compared to common indicators based on the cortisol response magnitude itself.

Blunted cortisol reactivity and risky driving in young offenders - a pilot study

Adolescent risky driving is a significant burden on public health. Young offenders (i.e. under custody and supervision of the criminal justice system) may be particularly vulnerable, but research is scant. Previous work indicated that blunted cortisol reactivity to stress is a marker of risk-taking predisposition, including risky driving. In this study, we hypothesized that young offenders display higher levels of risky driving than a non-offender comparison group, and that cortisol reactivity contributes to the variance in risky driving independent of other associated characteristics (i.e. impulsivity, risk taking, alcohol and drug use). We found that young offenders (n = 20) showed riskier driving in simulation than comparison group (n = 9), and blunted cortisol reactivity was significantly associated with risky driving. The results suggest young offenders are prone to risky driving, and that individual differences in the cortisol stress response may be an explanatory factor.

Blood lead levels and hypothalamic-pituitary-adrenal function in middle-aged individuals

Experimental and epidemiological studies suggested that exposure to lead (Pb) may influence the hypothalamic-pituitary-adrenal (HPA) axis. However, previous studies have yielded mixed results. We evaluated changes in basal salivary cortisol levels and acute cortisol responsivity to psychological stress in relation with blood Pb levels (BPb), in Caucasian individuals 50-67 years of age. Data were collected through the Study of Genetics, Stress and Cognitive Development (2004-2006). Diurnal basal and stress-reactive salivary cortisol levels were collected and BPb levels were determined using inductively coupled plasma mass spectroscopy. A total of 65 participants were included in the current study. General linear mixed models were used to assess the association between BPb level and change in cortisol secretion over time, for diurnal basal pattern and stress-reactive pattern, respectively. The geometric mean BPb was 2.70μg/dL (± 1.44) and two exposure groups were created based on the median value of 2.48µg/dL. No difference in geometric mean of salivary cortisol (µg/dL) at awakening was observed between High and Low BPb groups (0.23 (± 0.11) vs 0.20 (± 0.11), p = 0.36). The overall pattern of change in both diurnal basal (from the awakening to bedtime) and reactive salivary cortisol (during the stress induction protocol) did not differ between groups. In these middle-aged and older adults, we concluded that Pb exposure, within the range observed in the current study, was associated with neither diurnal nor stress-reactive cortisol secretion. Further investigation with larger datasets are needed to confirm our observations.

Lead exposure is related to hypercortisolemic profiles and allostatic load in Brazilian older adults

Lead levels (Pb) have been linked to both hyper- and hypo-reactivity of hypothalamic-pituitary-adrenal axis (HPA) axis to acute stress in animals and humans. Similarly, allostatic load (AL), the 'wear and tear' of chronic stress, is associated with inadequate HPA axis activity. We examined whether Pb levels would be associated with altered diurnal cortisol profile, as a primary mediator of AL, during aging. Pb levels were measured from blood samples (BPb) of 126 Brazilian individuals (105 women), between 50 and 82 years old. Six neuroendocrine, metabolic, and anthropometric biomarkers were analyzed and values were transformed into an AL index using clinical reference cut-offs. Salivary samples were collected at home over 2 days at awakening, 30-min after waking, afternoon, and evening periods to determine cortisol levels. A multiple linear regression model showed a positive association between BPb as the independent continuous variable and cortisol awakening response (R²=0.128; B=0.791; p=0.005) and overall cortisol concentration (R²=0.266; B=0.889; p<0.001) as the outcomes. Repeated measures ANOVA showed that individuals with high BPb levels showed higher cortisol at 30min after awakening (p=0.003), and in the afternoon (p=0.002) than those with low BPb values. Regarding AL, regression model showed that BPb was positively associated with AL index (R²=0.100; B=0.204; p=0.032). Correlation analyzes with individual biomarkers showed that BPb was positively correlated with HDL cholesterol (p=0.02) and negatively correlated with DHEA-S (p=0.049). These findings suggest that Pb exposure, even at levels below the reference blood lead level for adults recommended by the National Institute for Occupational Safety and Health and by the Center for Disease Control and Prevention, may contribute to AL and dysregulated cortisol functioning in older adults. Considering these findings were based on cross-sectional data future research is needed to confirm our exploratory results.

The DSM5/RDoC debate on the future of mental health research: implication for studies on human stress and presentation of the signature bank

In 2008, the National Institute of Mental Health (NIMH) announced that in the next few decades, it will be essential to study the various biological, psychological and social "signatures" of mental disorders. Along with this new "signature" approach to mental health disorders, modifications of DSM were introduced. One major modification consisted of incorporating a dimensional approach to mental disorders, which involved analyzing, using a transnosological approach, various factors that are commonly observed across different types of mental disorders. Although this new methodology led to interesting discussions of the DSM5 working groups, it has not been incorporated in the last version of the DSM5. Consequently, the NIMH launched the "Research Domain Criteria" (RDoC) framework in order to provide new ways of classifying mental illnesses based on dimensions of observable behavioral and neurobiological measures. The NIMH emphasizes that it is important to consider the benefits of dimensional measures from the perspective of psychopathology and environmental influences, and it is also important to build these dimensions on neurobiological data. The goal of this paper is to present the perspectives of DSM5 and RDoC to the science of mental health disorders and the impact of this debate on the future of human stress research. The second goal is to present the "Signature Bank" developed by the Institut Universitaire en Santé Mentale de Montréal (IUSMM) that has been developed in line with a dimensional and transnosological approach to mental illness.

Association between heavy metal exposure and poor working memory and possible mediation effect of antioxidant defenses during aging

BACKGROUND

Inverse associations have been observed between memory performance and blood concentrations of cadmium (Cd) and lead (Pb). Low antioxidant cell activity has also been linked to decline in memory due to aging. However, it has not yet been established whether the heavy metal-memory relationship is mediated by differences in antioxidant activity.

METHODS

We examined Cd and Pb levels, as well as oxidative stress parameters, in blood samples from 125 older adults (age range 50-82years). The Counting Span Test (CST) was used to evaluate working memory capacity (WMC). The Monte Carlo Method for Assessing Mediation (MCMAM) was used to analyze the mediation role of antioxidant activity in the heavy metals-memory association.

RESULTS

High blood Cd (BCd) concentration alone, and in combination with elevated blood Pb (BPb) concentration, was associated with poor WMC (p≤0.001) and low enzymatic antioxidant defenses (p≥0.006). The variance in WMC accounted for by BCd or by BCd combine with BPb was 20.6% and 18.6%, respectively. The MCMAM revealed that the influence of BCd and BPb concentrations on WMC was mediated by low antioxidant capacity (confidence interval - CI: 0.072 to -0.064 for BCd; CI: -0.062 to -0.045 for BPb).

CONCLUSION

These findings showed Pb and Cd blood concentration in older adults, even at levels below the current recommended threshold, was negatively associated with WMC and that this relationship may be partly mediated by low antioxidant defenses. Knowledge on the environmental factors that negatively influence brain and cognition during aging can help inform public policy strategies to prevent and control the adverse effects of environmental contaminant exposure during aging.

Prenatal and early-life polychlorinated biphenyl (PCB) levels and behavior in Inuit preschoolers

BACKGROUND

Whereas it is well established that prenatal exposure to polychlorinated biphenyls (PCBs) can disrupt children's behavior, early postnatal exposure has received relatively little attention in environmental epidemiology.

OBJECTIVES

To evaluate prenatal and postnatal exposures to PCB-153, a proxy of total PCB exposure, and their relation to inattention and activity in 5-year-old Inuits from the Cord Blood Monitoring Program.

METHODS

Prenatal exposure to PCBs was informed by cord plasma PCB-153 levels. We used a validated pharmacokinetic model to estimate monthly infants' levels across the first year of life. Inattention and activity were assessed by coding of video recordings of children undergoing fine motor testing. We used multivariable linear regression to evaluate the association between prenatal and postnatal PCB-153 levels and inattention (n=97) and activity (n=98) at 5years of age.

RESULTS

Cord plasma PCB-153 was not associated with inattention and activity. Each interquartile range (IQR) increase in estimated infant PCB-153 levels at 2months was associated with a 1.02% increase in the duration of inattention (95% CI: 0.04, 2.00). Statistical adjustment for the duration of breastfeeding slightly increased regression coefficients for postnatal level estimates, some of which became statistically significant for inattention (months: 2-4) and activity (months: 2-5).

CONCLUSIONS

Our study adds to the growing evidence of postnatal windows of development during which children are more susceptible to neurotoxicants like PCBs.

Cross-country differences in basal and stress-induced cortisol secretion in older adults

Objective

Several studies have emphasized the association between socioeconomic status (SES) and inadequate response of the biological stress system. However, other factors related to SES are rarely considered, such as cultural values, social norms, organization, language and communication skills, which raises the need to investigate cross-country differences in stress response. Although some studies have shown differences in cortisol levels between immigrants and natives, there is no cross-country evidence regarding cortisol levels in country-native elders. This is particularly important given the high prevalence of stress-related disorders across nations during aging. The current study examined basal diurnal and reactive cortisol levels in healthy older adults living in two different countries.

Methods

Salivary cortisol of 260 older adults from Canada and Brazil were nalyzed. Diurnal cortisol was measured in saliva samples collected at home throughout two working days at awakening, 30 min after waking, 1400 h, 1600 h and before bedtime. Cortisol reactivity was assessed in response to the Trier Social Stress Test (TSST) in both populations.

Results

Our results showed that even under similar health status, psychological and cognitive characteristics, Brazilian elders exhibited higher basal and stress-induced cortisol secretion compared to the Canadian participants.

Conclusion

These findings suggest that country context may modulate cortisol secretion and could impact the population health.

Household crowding is associated with higher allostatic load among the Inuit

BACKGROUND

Household crowding is an important problem in some aboriginal communities that is reaching particularly high levels among the circumpolar Inuit. Living in overcrowded conditions may endanger health via stress pathophysiology. This study examines whether higher household crowding is associated with stress-related physiological dysregulations among the Inuit.

METHODS

Cross-sectional data on 822 Inuit adults were taken from the 2004 Qanuippitaa? How are we? Nunavik Inuit Health Survey. Chronic stress was measured using the concept of allostatic load (AL) representing the multisystemic biological 'wear and tear' of chronic stress. A summary index of AL was constructed using 14 physiological indicators compiled into a traditional count-based index and a binary variable that contrasted people at risk on at least seven physiological indicators. Household crowding was measured using indicators of household size (total number of people and number of children per house) and overcrowding defined as more than one person per room. Data were analysed using weighted Generalised Estimating Equations controlling for participants' age, sex, income, diet and involvement in traditional activities.

RESULTS

Higher household crowding was significantly associated with elevated AL levels and with greater odds of being at risk on at least seven physiological indicators, especially among women and independently of individuals' characteristics.

CONCLUSIONS

This study demonstrates that household crowding is a source of chronic stress among the Inuit of Nunavik. Differential housing conditions are shown to be a marker of health inequalities among this population. Housing conditions are a critical public health issue in many aboriginal communities that must be investigated further to inform healthy and sustainable housing strategies.

Prenatal methylmercury, postnatal lead exposure, and evidence of attention deficit/hyperactivity disorder among Inuit children in Arctic Québec

BACKGROUND

Prenatal exposure to methylmercury (MeHg) and polychlorinated biphenyls (PCBs) has been associated with impaired performance on attention tasks in previous studies, but the extent to which these cognitive deficits translate into behavioral problems in the classroom and attention deficit/hyperactivity disorder (ADHD) remains unknown. By contrast, lead (Pb) exposure in childhood has been associated with ADHD and disruptive behaviors in several studies.

OBJECTIVES

In this study we examined the relation of developmental exposure to MeHg, PCBs, and Pb to behavioral problems at school age in Inuit children exposed through their traditional diet.

METHODS

In a prospective longitudinal study conducted in the Canadian Arctic, exposure to contaminants was measured at birth and at school age. An assessment of child behavior (n = 279; mean age = 11.3 years) was obtained from the child's classroom teacher on the Teacher Report Form (TRF) from the Child Behavior Checklist, and the Disruptive Behavior Disorders Rating Scale (DBD).

RESULTS

Cord blood mercury concentrations were associated with higher TRF symptom scores for attention problems and DBD scores consistent with ADHD. Current blood Pb concentrations were associated with higher TRF symptom scores for externalizing problems and with symptoms of ADHD (hyperactive-impulsive type) based on the DBD.

CONCLUSIONS

To our knowledge, this study is the first to identify an association between prenatal MeHg and ADHD symptomatology in childhood and the first to replicate previously reported associations between low-level childhood Pb exposure and ADHD in a population exposed to Pb primarily from dietary sources.

Salivary cortisol levels are associated with resource control in a competitive situation in 19 month-old boys

Glucocorticoids (GCs) have been related to social rank in many studies across species, a particular rank giving rise to a particular stress-related physiological profile. Our aim was to examine the hypothesis that GCs levels in toddlers would be related to social dominance in a competitive resource situation. Subjects were 376 toddlers from the Quebec Newborn Twin Study. At 19 months of age, each subject was exposed to 2 unfamiliar situations known to be moderately stressful at that age. Saliva was collected before and after the unfamiliar situations, to assess pre-test and reactive cortisol. Then the toddler reaction to a competitive situation for a toy with an unfamiliar peer was assessed and we measured the proportion of time the child controlled the resource. In girls, no association between cortisol levels and the proportion of time the child got the toy was found. On the other hand, in boys, increased cortisol levels before the unfamiliar situation were significantly related to a decreased proportion of time they got the toy in the competitive situation (r(174) = -0.17, P = 0.02). These results show that even in toddlers with limited social experience, association between GCs levels and social dominance can be found, an association that is specific to boys.

Environmental contaminants and human health in the Canadian Arctic

The third Canadian Arctic Human Health Assessment conducted under the Canadian Northern Contaminants Program (NCP), in association with the circumpolar Arctic Monitoring and Assessment Programme (AMAP), addresses concerns about possible adverse health effects in individuals exposed to environmental contaminants through a diet containing country foods. The objectives here are to: 1) provide data on changes in human contaminant concentrations and exposure among Canadian Arctic peoples; 2) identify new contaminants of concern; 3) discuss possible health effects; 4) outline risk communication about contaminants in country food; and 5) identify knowledge gaps for future contaminant research and monitoring. The nutritional and cultural benefits of country foods are substantial; however, some dietary studies suggest declines in the amount of country foods being consumed. Significant declines were found for most contaminants in maternal blood over the last 10 years within all three Arctic regions studied. Inuit continue to have the highest levels of almost all persistent organic pollutants (POPs) and metals among the ethnic groups studied. A greater proportion of people in the East exceed Health Canada's guidelines for PCBs and mercury, although the proportion of mothers exceeding these guidelines has decreased since the previous assessment. Further monitoring and research are required to assess trends and health effects of emerging contaminants. Infant development studies have shown possible subtle effects of prenatal exposure to heavy metals and some POPs on immune system function and neurodevelopment. New data suggest important beneficial effects on brain development for Inuit infants from some country food nutrients. The most successful risk communication processes balance the risks and benefits of a diet of country food through input from a variety of regional experts and the community, to incorporate the many socio-cultural and economic factors to arrive at a risk management decision that will be the most beneficial in Arctic communities.

The relation of environmental contaminants exposure to behavioral indicators in Inuit preschoolers in Arctic Quebec

Although lead (Pb) exposure has been identified as an important risk factor in child behavioral development, less is known regarding the relation between child behavior and exposure to polychlorinated biphenyls (PCBs) and mercury (Hg). Inuit children are particularly exposed to these chemicals and the aim of this study was to investigate the association between prenatal and postnatal exposure to Pb, PCBs, Hg and several aspects of behavioral function in Inuit preschoolers. The sample consisted of one hundred and ten 5-year-old Inuit children from Arctic Quebec. An umbilical cord blood sample was used to document prenatal exposure to Pb, PCBs and Hg. Child blood samples were collected at age 5 and the same contaminants were measured. A modified version of the Infant Behavior Rating Scale from the Bayley Scales of Infant Development-II was used to assess child behavior through examiners' ratings. Furthermore, attention, activity and emotional outcomes were assessed through behavioral coding of video recordings taken during fine motor testing. Pb exposure during childhood was associated with examiners ratings of greater impulsivity, irritability and with coding of observed inattention. Prenatal exposure to PCB 153 correlated with the examiners ratings of increased state of unhappiness and anxiety during the testing session, which was corroborated from video coding since cord PCB 153 was related to fewer manifestations of positive affects. No association was found with Hg exposure. These data corroborated those from previous Pb cohort studies and revealed an association between prenatal PCBs exposure and emotional outcomes in preschoolers.

The relation of low-level prenatal lead exposure to behavioral indicators of attention in Inuit infants in Arctic Quebec

The aim of this study was to investigate the association between prenatal exposure to lead (Pb) and several aspects of behavioral function during infancy through examiner ratings and behavioral coding of video recordings. The sample consisted of 169 11-month-old Inuit infants from Arctic Quebec. Umbilical cord and maternal blood samples were used to document prenatal exposure to Pb. Average blood Pb levels were 4.6 mug/dL and 5.9 mug/dL in cord and maternal samples respectively. The Behavior Rating Scales (BRS) from the Bayley Scales of Infant Development (BSID-II) were used to assess behavior. Attention was assessed through the BRS and behavioral coding of video recordings taken during the administration of the BSID-II. Whereas the examiner ratings of behaviors detected very few associations with prenatal Pb exposure, cord blood Pb concentrations were significantly related to the direct observational measures of infant attention, after adjustment for confounding variables. These data provide evidence that increasing the specificity and the precision of the behavioral assessment has considerable potential for improving our ability to detect low-to-moderate associations between neurotoxicants, such Pb and infant behavior.

Behavioural characteristics of two dairy breeds of cows selected (Hérens) or not (Brune des Alpes) for fighting and dominance ability

Two breeds of dairy cattle, one selected for intra-specific fighting and dominance ability (Hérens, H), the other not selected for this behavioural trait (Brune des Alpes, BA), submitted to the same management techniques, were compared with respect to their social behaviour (dominance, agonistic behaviour, social tolerance, social motivation, social distance), fear reactions, ease of handling and physiological correlates.As expected, cows from the H breed were dominant over the BA cows, they were also less fearful either in response to novel objects or in surprise effect tests and had higher social distances at pasture.On the contrary, H cows were less aggressive in undisturbed groups and more tolerant in a food-competition test than BA cows. There were no differences between the two breeds either in aggressive acts in encounters with unfamiliar animals, or in persistence in conflict situations.Furthermore, H cows were less easy to handle in a standardised test, and tended to be less socially motivated than BA cows. Lastly, H cows had higher plasma testosterone levels, and tended to present a lower increase in plasma cortisol level after a surprise effect than BA cows.Thus, the breeders' selection for fighting and dominance ability in H breed appears to have led to several behavioural and hormonal changes.