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Leliveld, L.M.C.; Düpjan, S.; Tuchscherer, A.; Puppe, B. |
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Title |
Behavioural and physiological measures indicate subtle variations in the emotional valence of young pigs |
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Journal Article |
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Year |
2016 |
Publication |
Physiology & Behavior |
Abbreviated Journal |
Physiol. Behav. |
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Volume |
157 |
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116-124 |
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Emotion; Heart rate; Vocalisation; Emotional valence; Animal welfare; Domestic pig |
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Abstract In the study of animal emotions, emotional valence has been found to be difficult to measure. Many studies of farm animals' emotions have therefore focussed on the identification of indicators of strong, mainly negative, emotions. However, subtle variations in emotional valence, such as those caused by rather moderate differences in husbandry conditions, may also affect animals' mood and welfare when such variations occur consistently. In this study, we investigated whether repeated moderate aversive or rewarding events could lead to measurable differences in emotional valence in young, weaned pigs. We conditioned 105 female pigs in a test arena to either a repeated startling procedure (sudden noises or appearances of objects) or a repeated rewarding procedure (applesauce, toy and straw) over 11 sessions. Control pigs were also regularly exposed to the same test arena but without conditioning. Before and after conditioning, we measured heart rate and its variability as well as the behavioural reactions of the subjects in the test arena, with a special focus on detailed acoustic analyses of their vocalisations. The behavioural and heart rate measures were analysed as changes compared to the baseline values before conditioning. A limited number of the putative indicators of emotional valence were affected by the conditioning. We found that the negatively conditioned pigs showed changes that were significantly different from those in control pigs, namely a decrease in locomotion and an increase in standing. The positively conditioned pigs, however, showed a stronger increase in heart rate and a smaller decrease in SDNN (a heart rate variability parameter indicating changes in autonomic regulation) compared to the controls. Compared to the negatively conditioned pigs, the positively conditioned pigs produced fewer vocalisations overall as well as fewer low-frequency grunts but more high-frequency grunts. The low-frequency grunts of the negatively conditioned pigs also showed lower frequency parameters (bandwidth, maximum frequency, 25% and 50% quartiles) compared to those of the positively conditioned pigs. In any of the statistically significant results, the conditioning accounted for 1.5–11.9% of variability in the outcome variable. Hence, we conclude that repeated moderate aversive and rewarding events have weak but measurable effects on some aspects of behaviour and physiology in young pigs, possibly indicating changes in emotional valence, which could ultimately affect their welfare. The combination of ethophysiological indicators, i.e., the concurrent examination of heart rate measures, behavioural responses and especially vocalisation patterns, as used in the current study, might be a useful way of examining subtle effects on emotional valence in further studies. |
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0031-9384 |
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Equine Behaviour @ team @ |
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6017 |
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Yarnell, K.; Hall, C.; Royle, C.; Walker, S.L. |
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Title |
Domesticated horses differ in their behavioural and physiological responses to isolated and group housing |
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Journal Article |
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Year |
2015 |
Publication |
Physiology & Behavior |
Abbreviated Journal |
Physiol.Behav. |
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143 |
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51-57 |
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Equine; Behaviour; Corticosterone; Housing |
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Abstract The predominant housing system used for domestic horses is individual stabling; however, housing that limits social interaction and requires the horse to live in semi-isolation has been reported to be a concern for equine welfare. The aim of the current study was to compare behavioural and physiological responses of domestic horses in different types of housing design that provided varying levels of social contact. Horses (n = 16) were divided equally into four groups and exposed to each of four housing treatments for a period of five days per treatment in a randomized block design. The four housing treatments used were single housed no physical contact (SHNC), single housed semi-contact (SHSC), paired housed full contact (PHFC) and group housed full contact (GHFC). During each housing treatment, adrenal activity was recorded using non-invasive faecal corticosterone metabolite analysis (fGC). Thermal images of the eye were captured and eye temperature was assessed as a non-invasive measure of the stress response. Behavioural analysis of time budget was carried out and an ease of handling score was assigned to each horse in each treatment using video footage. SHNC horses had significantly higher (p = 0.01) concentrations of fGC and were significantly (p = 0.003) more difficult to handle compared to the other housing types. GHFC horses, although not significantly different, had numerically lower concentrations of fGC and were more compliant to handling when compared to all other housing treatments. Eye temperature was significantly (p = 0.0001) lower in the group housed treatment when compared to all other treatments. These results indicate that based on physiological and behavioural measures incorporating social contact into the housing design of domestic horses could improve the standard of domestic equine welfare. |
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Equine Behaviour @ team @ |
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5920 |
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Christensen, J.W.; Beekmans, M.; van Dalum, M.; VanDierendonck, M. |
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Title |
Effects of hyperflexion on acute stress responses in ridden dressage horses |
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Journal Article |
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Year |
2014 |
Publication |
Physiology & Behavior |
Abbreviated Journal |
Physiol. Behav. |
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128 |
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39-45 |
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Behaviour; Dressage; Horse; Hyperflexion; Rein tension; Stress |
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The effects of hyperflexion on the welfare of dressage horses have been debated. This study aimed to investigate acute stress responses of dressage horses ridden in three different Head-and-Neck-positions (HNPs). Fifteen dressage horses were ridden by their usual rider in a standardised 10-min dressage programme in either the competition frame (CF), hyperflexion (“Low-Deep-and-Round”; LDR) or a looser frame (LF) in a balanced order on three separate test days. Heart rate (HR), heart rate variability parameters (HRV), behaviour and rein tension were recorded during the test. Salivary cortisol concentrations were measured 60min before and 0, 5, 15 and 30min after the test. Rein tension was significantly lower in LF and did not differ between CF and LDR; however approx. 15% of recordings in CF and LDR were above the sensor detection limit of 5kg. The horses had significantly higher cortisol concentrations directly after LDR compared to LF. In addition, the horses showed more distinctive head movements, including head waving, during LDR. There were no significant treatment effects on HR and HRV. In conclusion, the results indicate that LDR may be more stressful to these horses during riding. |
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0031-9384 |
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Equine Behaviour @ team @ |
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6507 |
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Ramos, D.; Reche-Junior, A.; Fragoso, P.L.; Palme, R.; Yanasse, N.K.; Gouvêa, V.R.; Beck, A.; Mills, D.S. |
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Title |
Are cats (Felis catus) from multi-cat households more stressed? Evidence from assessment of fecal glucocorticoid metabolite analysis |
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Journal Article |
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2013 |
Publication |
Physiology & Behavior |
Abbreviated Journal |
Physiol. Behav. |
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122 |
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72-75 |
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Feline; Housing; Non-invasive; Enzyme immunoassay; Cortisol |
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Abstract Given the social and territorial features described in feral cats, it is commonly assumed that life in multi-cat households is stressful for domestic cats and suggested that cats kept as single pets are likely to have better welfare. On the other hand, it has been hypothesized that under high densities cats can organize themselves socially thus preventing stress when spatial dispersion is unavailable. This study was aimed at comparing the general arousal underpinning emotional distress in single housed cats and in cats from multi-cat households (2 and 3–4 cats) on the basis of fecal glucocorticoid metabolites (GCM) measured via enzyme immunoassay (EIA). GCM did not significantly vary as a function of living style (single, double or group-housing); highly stressed individuals were equally likely in the three groups. Young cats in multi-cat households had lower GCM, and overall cats that tolerate (as opposed to dislike) petting by the owners tended to have higher GCM levels. Other environmental aspects within cat houses (e.g. relationship with humans, resource availability) may play a more important role in day to day feline arousal levels than the number of cats per se. |
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0031-9384 |
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Equine Behaviour @ team @ |
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5997 |
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Yarnell, K.; Hall, C.; Billett, E. |
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An assessment of the aversive nature of an animal management procedure (clipping) using behavioral and physiological measures |
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Journal Article |
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Year |
2013 |
Publication |
Physiology & Behavior |
Abbreviated Journal |
Physiol. Behav. |
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118 |
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32-39 |
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Thermography; Eye temperature; Cortisol; Horse; Welfare; Clipping |
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Animal management often involves procedures that, while unlikely to cause physical pain, still cause aversive responses. The domestic horse (Equus caballus) regularly has excessive hair clipped off to facilitate its use as a riding/driving animal and this procedure causes adverse behavioral responses in some animals. The aim of this study was to compare behavioral and physiological measures to assess the aversive effect of this procedure. Ten horses were selected on the basis of being either compliant (C: n=5) or non-compliant (NC: n=5) during this procedure. The horses were subjected to a sham clipping procedure (SC: where the blades had been removed from the clippers) for a period of ten minutes. Measures were taken pre, during and post SC (-10min to +30min) and mean values calculated for ALL horses and for C and NC separately. Behavioral activity was scored (scale 1-5) by twenty students from video footage in (phase/group-blind scoring). Heart rate (HR), salivary cortisol and eye temperature were monitored throughout the procedure. The NC horses were found to be significantly more behaviorally active/less relaxed throughout the trial than C horses (p<0.05) with the greatest difference occurring during the SC procedure (p<0.01). NC horses were more active/less relaxed during, compared with pre or post SC (p<0.05), but showed no behavioral difference pre and post SC. HR of the NC horses was higher than that of the C horses throughout the trial but only significantly so after 10min of SC (p<0.01). ALL horses showed a significant increase in HR between +5 and +10min into the procedure (p<0.05). There was a significant increase in salivary cortisol concentration in ALL horses post procedure (p<0.01) with levels peaking at 20minute post SC. No significant differences in salivary cortisol concentration between C and NC were found at any stage of the trial. Eye temperature increased significantly in ALL horses during SC, peaking at +10min into the procedure (p<0.05) and then decreased substantially when SC had ceased (p<0.01). Although no significant differences were found between C and NC per se, there was a significant interaction between group and phase of trial (p<0.05) with the NC group showing a greater decrease in eye temperature post SC. There was a significant positive correlation between changes in salivary cortisol concentration and eye temperature (p<0.01) but no correlation between any of the other measures. Although the behavioral response of C and NC to this procedure was significantly different the physiological responses indicated that ALL horses found the procedure aversive. Eye temperature could be used as an objective and immediate measure of how an animal is responding to a specific situation in order to evaluate management procedures and adapt them where appropriate to reduce the negative impact on animal health and welfare. |
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0031-9384 |
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Equine Behaviour @ team @ |
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6611 |
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Henry, S.; Zanella, A.J.; Sankey, C.; Richard-Yris, M.-A.; Marko, A.; Hausberger, M. |
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Adults may be used to alleviate weaning stress in domestic foals (Equus caballus) |
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2012 |
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Physiology & Behavior |
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106 |
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4 |
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428-438 |
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Weaning; Social influence; Abnormal behaviours; Young-adult interactions; Welfare; Horse |
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The present study aims to investigate whether the presence of unrelated adult horses at weaning would reduce the social stress of weaning and the emergence of undesirable behaviours. We tested this hypothesis in 32 domestic foals by comparing short and medium term behavioural and physiological responses to weaning in foals maintained in homogeneous groups of peers (PW) to those of foals grouped with both peers and unrelated adults (AW). In total, three trials were conducted, which each trial consisting of one AW group and one PW group. In all foals, weaning was followed by increased vocalization, increased locomotion and increased salivary cortisol concentration. However, signs of stress were less pronounced and shorter in duration in weanlings housed with unrelated adults (e.g. whinnies: p < 0.05; salivary cortisol: p < 0.05). Only foals without adults exhibited increased aggressiveness towards peers (p < 0.05) and abnormal behaviours (p < 0.05) such as excessive wood-chewing and redirected sucking towards peers. In conclusion, introducing adults to minimize weaning stress in foals and later on aggressiveness and abnormal behaviours appears as the most promising approach to date. |
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Equine Behaviour @ team @ |
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5689 |
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König von Borstel, U.; Euent, S.; Graf, P.; König, S.; Gauly, M. |
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Equine behaviour and heart rate in temperament tests with or without rider or handler |
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Journal Article |
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2011 |
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Physiology & Behavior |
Abbreviated Journal |
Physiol. Behav. |
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104 |
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3 |
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454-463 |
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Equine; Temperament; Human–animal interaction; Horseback riding; Heart rate variability; Reactivity |
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The aim of the present study was to compare horses' heart rate (HR), heart rate variability (RMSSD, pNN50) and behaviour in the same temperament test when being ridden, led, and released free. Behavioural measurements included scores and linear measurements for reactivity (R), activity (A), time to calm down (T) and emotionality (E), recorded during the approach (1) and/or during confrontation with the stimulus (2). Sixty-five horses were each confronted 3 times (1 ridden, 1 led, 1 free running in balanced order) with 3 novel and/or sudden stimuli. Mixed model analysis indicated that leading resulted in the lowest (P < 0.05 throughout) reactions as measured by A1, A2, E1, E2, R2, and pNN50 while riding produced the strongest (A1, T2, HR, RMSSD, pNN50) or medium (E1, E2, R2) reactions. Free running resulted either in the strongest (A2, E1, E2, R2) or in the lowest (A1, T2, HR, RMSSD, pNN50) reactions. The repeatability across tests for HR (0.57), but not for RMSSD (0.23) or pNN50 (0.25) was higher than for any behavioural measurement: the latter ranged from values below 0.10 (A1, A2, T2) to values between 0.30 and 0.45 (E1, E2, R2). Overall, the results show that a rider or handler influences, but not completely masks, the horses' intrinsic behaviour in a temperament test, and this influence appeared to be stronger on behavioural variables and heart rate variability than on the horses' heart rates. Taking both practical considerations and repeatabilities into account, reactivity appears to be the most valuable parameter. Emotionality and heart rate can also yield valid results reflecting additional dimensions of temperament although their practical relevance may be less obvious. If a combination of observed variables is chosen with care, a valid assessment of a horse's temperament may be possible in all types of tests. However, in practice, tests that resemble the practical circumstances most closely, i.e. testing riding horses under a rider, should be chosen. |
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Equine Behaviour @ team @ |
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5641 |
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Sankey, C.; Henry, S.; Clouard, C.; Richard-Yris, M.-A.; Hausberger, M. |
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Asymmetry of behavioral responses to a human approach in young naive vs. trained horses |
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2011 |
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Physiology & Behavior |
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104 |
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3 |
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464-468 |
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Laterality; Emotionality; Human approach; Horse |
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The aim of this study was to investigate the impact of training experience on young horses (Equus caballus)’ lateralized responses to an approaching human. The results show that the one year old untrained horses display asymmetrical responses to an approaching human, with more negative reactions (escapes, threats) when approached from the left side, while approaches towards the right shoulder elicited more positive behaviors. On the contrary, two years old trained horses reacted equally positively to approaches and contact on both sides. Our findings support those of previous studies investigating a link between emotionality and laterality and confirm the role of the left hemisphere in the processing of novel or negative stimuli. Moreover, the data underline the impact work and training can have on this laterality in horses. |
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Equine Behaviour @ team @ |
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5688 |
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Beerda, B.; Schilder, M.B.H.; Janssen, N.S.C.R.M.; Mol, J.A. |
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The Use of Saliva Cortisol, Urinary Cortisol, and Catecholamine Measurements for a Noninvasive Assessment of Stress Responses in Dogs |
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1996 |
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Hormones and Behavior |
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Horm. Behav. |
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30 |
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3 |
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272-279 |
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A problem in assessing animal welfare is that collecting data in itself may be stressful to the animals. Therefore, noninvasive methods for collecting data have to be devised and tested. A first step in investigating saliva cortisol, urinary cortisol, and urinary catecholamine as noninvasive indicators of canine well-being is the validation of these hormonal measures as alternatives for those in plasma. Using a model of insulin (0.2 U/kg)-induced hypoglycemia, we report on stress-induced responses in saliva cortisol, urinary cortisol, and urinary catacholamines relative to cortisol and catecholamine responses in plasma. Hypoglycemia in six dogs induced significant (P< 0.05) increases in plasma cortisol and adrenaline but not noradrenaline. Saliva cortisol responses expressed as net area under the response curve correlated significantly with plasma cortisol responses (r> 0.92). Saliva cortisol levels measured 7 to 12% of plasma cortisol concentrations. Cortisol/creatinine ratios in urine were significantly higher when voided after insulin administeration, compared to when voided after saline treatment. Insulin-induced increments in cortisol/creatinine ratios were nonsignificant when urine samples were assayed after dichloromethane extraction. Although urinary adrenaline/creatinine (A/C) ratios were significantly correlated with maximum plasma adrenaline values after insulin administration, A/C ratios did not differ significantly between insulin and saline treatment. The present experiment provides strong support for using saliva sampling and urine collection as noninvasive methods to establish stress-induced cortisol responses. For measuring acute plasma adrenaline responses, measuring A/C ratios may not be a valid alternative. |
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0018-506x |
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Equine Behaviour @ team @ |
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5574 |
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Romero, L.M.; Dickens, M.J.; Cyr, N.E. |
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The reactive scope model — A new model integrating homeostasis, allostasis, and stress |
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2009 |
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Hormones and Behavior |
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Horm. Behav. |
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55 |
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3 |
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375-389 |
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Stress; Allostasis; Glucocorticoids; Fight-or-flight; Homeostasis |
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Allostasis, the concept of maintaining stability through change, has been proposed as a term and a model to replace the ambiguous term of stress, the concept of adequately or inadequately coping with threatening or unpredictable environmental stimuli. However, both the term allostasis and its underlying model have generated criticism. Here we propose the Reactive Scope Model, an alternate graphical model that builds on the strengths of allostasis and traditional concepts of stress yet addresses many of the criticisms. The basic model proposes divergent effects in four ranges for the concentrations or levels of various physiological mediators involved in responding to stress. (1) Predictive Homeostasis is the range encompassing circadian and seasonal variation — the concentrations/levels needed to respond to predictable environmental changes. (2) Reactive Homeostasis is the range of the mediator needed to respond to unpredictable or threatening environmental changes. Together, Predictive and Reactive Homeostasis comprise the normal reactive scope of the mediator for that individual. Concentrations/levels above the Reactive Homeostasis range is (3) Homeostatic Overload, and concentrations/levels below the Predictive Homeostasis range is (4) Homeostatic Failure. These two ranges represent concentrations/levels with pathological effects and are not compatible with long-term (Homeostatic Overload) or short-term (Homeostatic Failure) health. Wear and tear is the concept that there is a cost to maintaining physiological systems in the Reactive Homeostasis range, so that over time these systems gradually lose their ability to counteract threatening and unpredictable stimuli. Wear and tear can be modeled by a decrease in the threshold between Reactive Homeostasis and Homeostatic Overload, i.e. a decrease in reactive scope. This basic model can then be modified by altering the threshold between Reactive Homeostasis and Homeostatic Overload to help understand how an individual's response to environmental stressors can differ depending upon factors such as prior stressors, dominance status, and early life experience. We illustrate the benefits of the Reactive Scope Model and contrast it with the traditional model and with allostasis in the context of chronic malnutrition, changes in social status, and changes in stress responses due to early life experiences. The Reactive Scope Model, as an extension of allostasis, should be useful to both biomedical researchers studying laboratory animals and humans, as well as ecologists studying stress in free-living animals. |
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0018-506x |
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Equine Behaviour @ team @ |
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5583 |
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