Behavioural, saliva cortisol and heart rate responses to different types of stimuli in dogs

Evaluation of an easy-to-use protocol for assessing behaviors of dogs retiring from commercial breeding kennels

Objective, reliable behavioral tests are needed to refine on-site welfare assessments of dogs housed at commercial breeding (CB) kennels and provide a basis to inform predictions of their behavior when retired from such kennels. This study tested the reliability, construct validity, and applicability of a protocol for the behavioral assessment of dogs from CB kennels that might be useful in comprehensive welfare assessments of this population. A sample of 447 dogs from 26 CB kennels in the Midwestern US were assessed in their pens. Responses to an approach test (performed on three consecutive days) and a behavioral reactivity test (e.g., traffic cone, toys, umbrella) were recorded. Results showed moderate to perfect (Kw = 0.51-1.00) inter-rater reliability between three independent observers. Approach test-retest analysis showed high correlation of approach test scores on days 1, 2 and 3 (r = 0.85, p<0.0001). Exploratory factor analysis extracted four main factors: Food Motivation (F1), Sociability (F2), Boldness (F3) (e.g., response to novel objects), and Responsiveness (F4) (e.g., response to an umbrella opening) confirming the ability of the test to measure behaviors of interest. All factors showed high internal consistency (Cronbach's alpha 0.81-0.93) further supporting the robustness of the test construct. The demonstrated reliability of this protocol suggests that it may be usefully applied to assessing the behavior of dogs as a component of their welfare assessment in CB kennels. Doing so using even larger sample sizes may yield insights on the effects of housing and management practices on dog welfare while at the kennels, which may also help inform approaches that improve rehoming outcomes for retiring breeding dogs. Practical applications and limitations are outlined.

Evaluating the accuracy of facial expressions as emotion indicators across contexts in dogs

Facial expressions potentially serve as indicators of animal emotions if they are consistently present across situations that (likely) elicit the same emotional state. In a previous study, we used the Dog Facial Action Coding System (DogFACS) to identify facial expressions in dogs associated with conditions presumably eliciting positive anticipation (expectation of a food reward) and frustration (prevention of access to the food). Our first aim here was to identify facial expressions of positive anticipation and frustration in dogs that are context-independent (and thus have potential as emotion indicators) and to distinguish them from expressions that are reward-specific (and thus might relate to a motivational state associated with the expected reward). Therefore, we tested a new sample of 28 dogs with a similar set-up designed to induce positive anticipation (positive condition) and frustration (negative condition) in two reward contexts: food and toys. The previous results were replicated: Ears adductor was associated with the positive condition and Ears flattener, Blink, Lips part, Jaw drop, and Nose lick with the negative condition. Four additional facial actions were also more common in the negative condition. All actions except the Upper lip raiser were independent of reward type. Our second aim was to assess basic measures of diagnostic accuracy for the potential emotion indicators. Ears flattener and Ears downward had relatively high sensitivity but low specificity, whereas the opposite was the case for the other negative correlates. Ears adductor had excellent specificity but low sensitivity. If the identified facial expressions were to be used individually as diagnostic indicators, none would allow consistent correct classifications of the associated emotion. Diagnostic accuracy measures are an essential feature for validity assessments of potential indicators of animal emotion.

Detecting Welfare in a Non-Verbal Species: Social/Cultural Biases and Difficulties in Horse Welfare Assessment

Simple Summary

There is a paradox about the welfare of horses in the domestic situation: on the one hand, horses are beloved partners for most owners, but on the other hand, scientific studies are converging to show that there is a high prevalence of welfare problems. There seems to be a mismatch between theoretical knowledge and field applications. In this review, we aim at disentangling the possible factors explaining such a paradox. Among them, we consider the impact of anthropomorphic and cultural biases, popular beliefs, but also overexposure to horses with compromised welfare state, which can change owners’ representation of what is a “normal” horse, on the undervaluation of horse welfare state. We suggest that, rather than simply having knowledge on what should be done, identifying the horse welfare state using validated animal-based indicators is essential to identify and promote best practices.

Abstract

Horses were domesticated for more than 5000 years and have been one of the most emblematic species living alongside humans. This long-shared history would suggest that horses are well known and well understood, but scientific data raise many concerns about the welfare state of most domestic horses suggesting that many aspects have been largely misunderstood. In the present review, we will examine some of the possible human factors that may explain the huge prevalence of welfare problems, despite horses being of special importance to humans. First of all, as horses are non-verbal, current management practices rely upon what one thinks is good for them, which opens the way to subjective interpretations and projections, based on one’s own subjective experience but probably still more on cultural/social norms and influences, traditions and beliefs. The lack of recognition, identification, or even the misinterpretation of signals are other potential reasons for welfare issues. Lastly, the over-exposure to animals with expressions of compromised welfare may lead to lower sensitivity of owners/professionals. That is why we lastly suggest that instead of simply providing information on what to do, we should promote validated visible indicators that leave less room for personal interpretation.

Life experience rather than domestication accounts for dogs' increased oxytocin release during social contact with humans

Dogs' increased human-directed sociability compared to wolves may be the result of increased oxytocin system activity and decreased stress responses, but comparative studies accounting for life experience are lacking. We compared hand-raised, pack-living wolves' and dogs' behavior and hormone concentrations after interacting with a closely bonded and a familiar human. Both preferred the bonded partner, but dogs showed less variability in human-directed sociability than wolves. Physical contact was not associated with oxytocin but correlated positively with glucocorticoids in the pack-living animals when the human was not bonded. To clarify the role of life experience, we tested pet dogs and found that oxytocin concentrations correlated positively with physical contact with their owners, while glucocorticoids remained unaffected. Results show that, given similar experiences, wolf-dog differences in human-directed sociability and associated hormones are subtle and indicate that factors related to life as a pet dog rather than domestication account for oxytocin release during human-dog interactions.

Effects of a new dietary supplement on behavioural responses of dogs exposed to mild stressors

Background & Objectives

The effectiveness of a new dietary supplement (derived from fish hydrolysate and melon juice concentrate rich in superoxide dismutase) in reducing fear and stress‐related behaviours in pet dogs was examined in a double‐blind, placebo‐controlled, randomized study.

Methods

39 dogs were recruited after the owners had filled out a fear susceptibility index questionnaire. Over a 30‐day period, one group of dogs received the supplement, and another group a placebo.

Twelve behavioural variables were recorded in a series of four subtests (ST1‐ST4) on days 0, 15 and 30. Saliva cortisol levels were measured before and after each set of STs.

Results

The dogs rated as more fearful displayed significantly higher cortisol values before the day 0 test session, were less active, spent less time playing with the experimenter, and approached the unfamiliar object less frequently. The owners did not correctly guess whether their dog had received the supplement or not. Behaviours of dogs were significantly different across the three sessions, with significant increases of stress‐related behaviours (time spent in the door zone, number of interactions with the door, of whining, and of lip‐licking). Conversely time spent with the experimenter increased, interactions and curiosity for the novel object and play with the experimenter decreased, presumably due to a habituation process. This suggests that the design of the four subtests session was relevant to test for mild stressors situations. Moreover, supplemented and placebo dogs responded differently to the three test sessions, indicating a supplement effect on dogs' behaviours and their adaptation to mild stressors situations.

Conclusion

The trial results suggested that the supplement facilitates activity and curiosity in a familiar environment, promotes dog‐human interactions with an increased human familiarity, and tends to reduce subtle stress behaviours. Our results suggest that the supplement was effective in the context of mild stressors and habituation.

Salivary cortisol in healthy dogs: a randomized cross-over study to evaluate different saliva stimulation methods and their effects on saliva volume and cortisol concentration

BACKGROUND

Salivary cortisol collected at home is a useful test to diagnose and monitor Cushing's syndrome in humans. The main problem in dogs is to retrieve a sufficient amount of saliva. The aim of this study was to evaluate different salivary collection methods and compare their effects on volume, pH and cortisol concentration of saliva. Sixteen healthy Beagles were used in a 4 × 4 randomized crossover study with a washout period of 1 week between each of the following collection methods: 1. Salimetrics® cotton swab dipped in ginger powder (ginger group); 2. beef-flavored Salimetrics® (bouillon group); 3. Salivette® cotton swab with an enclosed treat (treat group); 4. plain Salimetrics® (control group). First, baseline saliva (plain cotton swab, S0) and, 2 min later, experimental saliva (according to group allocation above, SExp) were collected. Saliva was gathered by holding the swabs in the animal's mouth for 2 min. After the cross-over study, another saliva sample was collected from all dogs by the ginger method, using a 30 s sampling time (30s-ginger method). Cortisol concentrations were measured by liquid chromatography tandem mass spectrometry.

RESULTS

All three stimulation methods increased saliva production significantly (S0 compared to SExp: ginger p = 0.0005; bouillon p = 0.009; treat p = 0.007). Only ginger stimulation, however, generated a significantly higher amount of saliva (SExp) compared to the control group (p = 0.00001; median (range) amount of saliva for SExp: ginger 1200 ul (600-1700), bouillon 650 ul (200-1900), treat 700 ul (300-1000), control 400 ul (0-1100)). The amount of saliva retrieved by the 30s-ginger method was still higher than that from the control group (p = 0.0004). Bouillon and treat stimulation led to decreased pH values (bouillon, p = 0.0028; treat, 0.0018). Excitement was higher in the ginger group (p = 0.01). Chewing was intensified in the ginger and treat group (ginger, p = 0.003; treat, 0.0009). The cortisol concentration SExp was higher compared to that of S0 in the ginger and treat group (p = 0.02, 0.003). The experimental cortisol concentrations (SExp) were not different between groups.

CONCLUSIONS

The 30s-ginger method could prove useful in evaluating or monitoring dogs with Cushing's syndrome, as sampling at home for 30 s by the owner seems feasible.

Artificially elevated oxytocin concentrations in pet dogs are associated with higher proximity-maintenance and gazing towards the owners

The relationship between dogs and their owners is characterized by an affective and enduring bond. It has been suggested that oxytocin might be the underlying mechanism driving this relationship, however evidence is mixed. In this study we tested whether intranasally administered oxytocin (compared to saline) would influence dogs' behavioural synchrony and shared attention towards their owners. Each individuals' pre and post administration oxytocin concentrations (measured in urine) were included in the analyses. Urinary oxytocin concentrations after administrations were positively associated with dogs' duration of social proximity and looking behaviours towards their owners supporting the role of oxytocin in modulating dogs' human-directed social behaviours.

Two Ends of the Leash: Relations Between Personality of Shelter Volunteers and On-leash Walking Behavior With Shelter Dogs

Human personality influences the way people interact with dogs. This study investigated the associations between the personality of animal shelter volunteers and behavior during on-leash walks with shelter dogs. Video recording and a canine leash tension meter were used to monitor the on-leash walking. Personality was measured in five dimensions (neurotic, extroverted, open, agreeable and conscientious) with the NEO Five-Factor Inventory (NEO-FFI). Neurotic volunteers pulled the leash harder and tended to interact with dogs using more body language; dogs being walked by neurotic volunteers in turn displayed more lip-licking and body shaking and were more likely to be rated as well-behaved. Extroverted volunteers were associated with stronger maximal leash tension at both the human and dog ends of the leash, and they praised the dog more, often in a high pitched voice. These volunteers eliciting more tail-wagging and body shaking by the dog. Extroverted volunteers were also more tolerant of different dog behaviors. Volunteers with personalities characterized by "openness to experiences" were less likely to verbally attract the attention of dogs, praise dogs and talk to them in a high-pitched voice; however, dogs walked by these volunteers were more likely to pull on the leash, and engaged in more lip-licking but less sniffing. "Agreeable" volunteers liked to verbally attract the attention of the dogs and more commonly initiated hand gestures and physical contact, causing the dogs to pull less frequently; dogs in these dyads displayed more gazing and lip-licking behaviors. Conscientious volunteers were less likely to pull the leash and tended to have more physical contact with the dogs but did not favor verbal communication and did not use a high pitched voice.

Evaluation of associations between owner presence and indicators of fear in dogs during routine veterinary examinations

OBJECTIVE

To evaluate the influence of owner presence on behavioral and physiologic indicators of fear in dogs during routine physical examinations.

ANIMALS

32 client-owned dogs.

PROCEDURES

Dogs underwent a standardized, video-recorded examination consisting of 6 phases (examination of the head, lymph node palpation, body palpation, axillary temperature measurement, heart rate assessment, and respiratory rate assessment) with or without their owner present in a randomized, controlled study. Behaviors reported to be indicative of fear, including reduced posture, avoidance, escape, lip licking, body shaking, yawning, and vocalizing, were assessed during each phase, and physiologic measurements were assessed during relevant phases by the investigator. Owner presence and sex and age of dogs were investigated for associations with behavioral signs of fear; behavioral and physiologic measurements were compared between groups (owner present vs owner absent).

RESULTS

Dogs in the owner-present group had a lower rate of vocalizations, lower mean axillary temperature, and higher rate of yawning than dogs in the owner-absent group. Female dogs in the owner-absent group had a higher heart rate than females and males in the owner-present group and males in the owner-absent group, and the rate of lip licking decreased as age increased in the owner-present group. The presence of reduced body posture and rates of lip licking, avoidance behavior, and escape behavior were associated with examination phase.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggested that, when practical, owners should be encouraged to remain with their dog during routine veterinary examinations. However, effects of owner presence during procedures require further investigation. (J Am Vet Med Assoc 2020;257:1031-1040).

Socialization in Commercial Breeding Kennels: The Use of Novel Stimuli to Measure Social and Non-Social Fear in Dogs

Simple Summary

Owner-based reports of dogs presumed to come from commercial breeding kennels (CBKs) suggest high levels of fear in this population. Fear in kenneled dogs is a serious behavioral welfare concern as it may lead to both acute and chronic stress. Novel social and non-social stimuli have been shown to elicit behaviors associated with fear in animals. New knowledge on the levels of fear in dogs from CBKs could be used to further refine protocols intended for assessment of welfare in CBKs and to improve breeders’ management practices. The aim of this study, therefore, was to evaluate how dogs from CBKs reacted to social (i.e., a person approaching) and non-social (i.e., a traffic cone and a dog statue) stimuli, and to perform a preliminary evaluation of how these responses might be used as indicators of dogs’ overall socialization levels in kennels. Results revealed that dogs had primarily mildly fearful responses to the stimuli presented. These findings are encouraging as extreme fearful reactions were rarely recorded. Nevertheless, there is a clear margin for commercial breeders to improve the socialization protocols in their kennels to better incorporate both social and non-social stimuli.

Abstract

Understanding the behavioral welfare of dogs in commercial breeding kennels (CBKs) is important for improving breeders’ management practices as well as dog welfare. In the current study, breeding dogs from CBKs were exposed to novel stimuli to evaluate their behavioral responses, with emphasis on indicators of fear. Subjects were presented with a standard stranger-approach test, a traffic cone, and a realistic dog statue. Sixty dogs were exposed to the three stimuli and behavioral responses were scored using an ethogram developed for this study. Dogs spent significantly more time investigating the environment, staying further away from the stimulus, and they took longer to approach and investigate when presented with the cone than with the dog statue or stranger (p < 0.01). These findings suggest that the cone elicited more fear-related behaviors than the dog statue and stranger. Given these results, in addition to socializing their dogs to unfamiliar people and other dogs within their kennels, commercial breeders should be encouraged to increase the exposure of their dogs to more diverse novel stimuli to reduce non-social fear and support the welfare of dogs while they reside in the kennel and when they transition to new homes.

Do Service Dogs for Veterans with PTSD Mount a Cortisol Response in Response to Training?

Simple Summary

A growing number of people are supported by specialized service dogs. These dogs are highly trained to improve human welfare, yet not much is known about their own welfare. One of the ways in which welfare can be measured is through the expression of stress via the hormone cortisol. In this study, we investigated the level of cortisol in saliva, a measure for physiological stress, in 19 service dogs. We measured cortisol in the dogs’ saliva 15 min after arrival at a training ground, before partaking in a training session for service dogs, after participation in the training session, and after a 45-min free play period. We found no elevated levels of cortisol after the training session. Instead, we found that cortisol had lowered when compared to before the training. Additionally, we found that cortisol was highest 15 min after arriving at the training round and after 45 min of free play. This led to the conclusion that dogs in our study did not seem to have a stress response in response to participation in the training.

Abstract

Only a few studies have investigated the welfare of animals participating in animal-assisted interventions (AAIs). Most of these studies focus on dogs in therapeutic settings. There are, however, also dogs—service dogs—that are employed to continuously support a single human. Because the welfare of these service dogs is important for the sustainability of their role, the aim of this study was to investigate their stress response to service dog training sessions. To do this, we took repeated salivary cortisol samples from dogs who participated in a training session (n = 19). Samples were taken just after arrival at the training ground, before training, after training, and after a period of free play. Our results showed that mean cortisol levels in all samples were relatively low (between 1.55 ± 1.10 and 2.73 ± 1.47 nmol/L) compared to similar studies. Analysis further showed that samples taken before and after participation in the training’s session did not differ from one another. Mean cortisol levels in both situations were additionally lower than those upon arrival at the training site and after a period of free play. This led to the conclusion that the dogs in our study did not seem to experience training as stressful.

Effects of Human Presence and Voice on the Behaviour of Shelter Dogs and Cats: A Preliminary Study

Simple Summary

Environmental enrichment is fundamental for the welfare of shelter animals. This study compared the behaviour of single-housed shelter dogs and cats while being read a book (using a prerecording) in the presence of an unfamiliar human (without direct physical contact) or in its absence. Behaviours such as scratching the door, gaze direction and location in relation to the audio source/human were observed for 10 min. When a human was present, dogs spent longer in their bed and looking at the auditory source, while cats scratched the door and rubbed against the door. In the absence of the human, cats tended to spend more time in the vertical dimension, where the hiding boxes were located. Overall, the presence of a person, combined with auditory enrichment, induced greater interest compared to just an audio stimulation in both shelter dogs and cats. However, some animals showed signs of frustration likely due to not being able to physically interact with the human. Given that dogs that exhibit calmness and cats that scratch the door in the presence of humans and try to attract human attention are more likely to be adopted, auditory enrichment combined with human presence promotes behaviours that may consequentially increase adoption rate.

Abstract

Reading books to shelter animals combining auditory enrichment with human presence is increasingly used although its effects on animal welfare have not yet been investigated. This study compared the behaviour of single-housed shelter dogs and cats during a prerecorded reading condition in the absence or presence of an unfamiliar human (without direct physical contact). Fourteen dogs and twenty-one cats were observed in their enclosure in the two conditions in a counterbalanced order. Behaviours such as scratching the door, gaze direction and location in relation to the audio source/human were analysed from video recording for 10 min per condition. Dogs spent more time in their bed (p < 0.047) and looking at the auditory source (p < 0.004) when a human was present. Cats showed door scratching and rubbing when a human was present (p < 0.043), whereas they tended to spend more time in the vertical dimension (p = 0.051), where the hiding boxes were located, during auditory stimulation without a human present. These results show that the presence of a human induces greater interest compared to just audio stimulation in shelter dogs and cats but may induce frustration likely due to not being able to physically interact in some animals.

Early Evaluation of Fearfulness in Future Guide Dogs for Blind People

Fear is the leading cause of guide dog failure. Detecting the nature and causes of these fears as early as possible is the first step in preventing their occurrence. The process of habituation is a fundamental part of fear prevention. In this study, 11 puppies, all five months of age, underwent an emotional reactivity test (ERT) composed of 12 scored items, classified into three categories: unknown person (UP), sound and visual stimuli (SVS), and body sensitivity (BS). Salivary cortisol was also measured. Foster families were asked to complete a questionnaire concerning puppies' habituation. The physiological data were correlated with UP (r = 0.71) and BS scores (r = 0.67), but not with SVS scores (r = 0.16), suggesting the ability of these dogs to control themselves when faced with the latter stimulus category. Additionally, the more time a puppy spent alone, the more likely it was to be afraid of SVS (p = 0.05). A correlation, albeit moderate, was detected between cortisol and habituation scores (r = 0.48). These results give us interesting avenues to explore, particularly regarding the importance of focusing on early puppy socialization and habituation to improve the numbers of guide dog candidates becoming successful guide dogs.

Characteristics and Welfare of Long-Term Shelter Dogs

Simple Summary

In no-kill shelters, overpopulation is an often-faced problem. Some individuals have better adoption chances than others, and over time, long-term dog populations develop. Our aim was to identify certain characteristics that long-term shelter dogs share and to investigate if long-term shelter dogs experience an impairment of welfare due to the restricted environment. In our study, long-term shelter dogs were more often of older age, male, of large size, neutered, and of a “dangerous breed”. They were also described more often as having behavioural problems regarding aggression and high arousal. The physical wellbeing of long-term shelter dogs was not impaired. However, they did show some stress-related behaviours, suggesting that they might be more affected by acute stressors and have more difficulties relaxing in the shelter environment. In sum, certain morphological and behavioural characteristics of dogs can be used to identify individuals at higher risk for a long-term stay. Thus, these dogs require special attention and effort to enhance their adoption chances. The results of this study serve as a scientific basis for developing such dog-specific strategies.

Abstract

To identify characteristics that distinguish long-term (LT: stay > 1 year) from short-term shelter dogs (ST: ≤5 months) and to investigate if a long-term stay impairs welfare, we compared ST and LT dogs in Austrian no-kill shelters. Analyses including characteristics such as breed, sex, or age (shelter records), problem behaviour, and personality (questionnaires completed by staff) showed that LT dogs were significantly more often a “dangerous breed”, male, and older when admitted to the shelter. They were rated higher on “aggression” and “high arousal” and lower on the personality dimension “amicability”. A welfare assessment protocol including reaction toward humans (Shelter Quality Protocol), and in-kennel observations were used to assess the effect of the long-term stay. LT dogs tended to show more signs of aggression toward an unfamiliar human, but welfare assessment revealed no difference. During resting periods, LT dogs spent more time resting head up and had more bouts resting head down. Prior to feeding, they stood, vocalised, and yawned more. LT dogs are characterised by specific features such as being aroused easily and having difficulties to relax. Whether this is a result of the long-term stay or personality-associated, consequently causing lower adoption rates, remains to be determined.

Does stress run through the leash? An examination of stress transmission between owners and dogs during a walk

Humans and dogs have co-evolved for over 10,000 years. Recent research suggests that, through the domestication process, dogs have become proficient at responding to human commands, attention and emotional states. However, the extent to which a companion dog responds to human emotions, such as stress, remains to be understood. This study examines whether a companion dog's stress, as measured by cortisol levels and heart rate, increases during a familiar outdoor walk in response to its owner's experience of stress. Sixty-eight owner/dog dyads participated in this study. The dyads were randomly assigned to an Experimental or Control group. Owners in the Experimental group were informed the walk would be digitally recorded for subsequent evaluation of their handling skills, whereas those in the Control group were informed the walk would be digitally recorded for archival purposes (no evaluation). This manipulation was implemented to induce a mild stress response in the owners. Salivary cortisol samples were collected from the owner and their dog before and after the walk. The dyad was also fitted with monitoring devices to record heart rate throughout the walk. Finally, personality information regarding the owner and their dog was collected. We found that cortisol production within the dyad showed a marginal inverse correlation. We also found that owners' Openness to Experience and dogs' Fearfulness influenced the heart rate of the other during the first minute of a walk. These results support that although stress may be detected within a dyad, this does not result in an associated significant change in cortisol or heart rate.

Do Canine Behavioural Assessments and Characteristics Predict the Human-Dog Interaction When Walking on a Leash in a Shelter Setting?

Simple Summary

We explored 370 human-dog interactions in an animal shelter when volunteers walked shelter dogs on a leash, considering the effects of canine demographics and the results of the shelter’s canine behavioural assessments. Results showed that dogs that were more relaxed during the shelter assessment (i.e., when socialising with humans or being left alone in a new environment) were less reactive on the leash, with lower tension and pulling frequency. Moreover, socialised and relaxed dogs displayed more positive body language, such as tail in a high position, gazing at the handler, and exploring the environment. When walking with these dogs, volunteers utilised fewer verbal guidance cues and body language during the walk. In addition to the canine behaviour assessment, there were correlations between canine demographics (i.e., age, skull shape, body size, and previous ownership history) and the behavioural interaction and humans’ perception. Finally, volunteers perceived the walk as less satisfactory when they needed to pull the leash harder during the walk. This research suggests that the RSPCA behavioural assessment may be useful in predicting the behaviour of shelter dogs when walked by volunteers.

Abstract

Inappropriate leash reactivity is one of the most common problems in shelter dogs, which negatively affects the health of dogs and reduces their adoptability. We explored 370 human-dog interactions, involving 74 volunteers and 111 dogs, in an animal shelter when volunteers walked shelter dogs on a leash, considering the effects of canine demographics and the results of the shelter’s canine behavioural assessments. The interaction was video recorded and coded using ethograms, and a leash tension meter was used to measure the pull strength of dogs and handlers. Results showed that dogs that were more relaxed during the shelter assessment (i.e., when socialising with humans or being left alone in a new environment) were less reactive on the leash, with lower tension and pulling frequency. Moreover, socialised and relaxed dogs displayed more positive body language, such as tail in a high position, gazing at the handler, and exploring the environment. When walking with these dogs, volunteers utilised fewer verbal cues and body language during the walk. In addition to the canine behaviour assessment, there were correlations between canine demographics and the behavioural interaction and humans’ perception. Finally, volunteers perceived the walk as less satisfactory when they needed to pull the leash harder during the walk. This research suggests that the RSPCA behavioural assessment may be useful in predicting the behaviour of shelter dogs when walked by volunteers.

Does training method matter? Evidence for the negative impact of aversive-based methods on companion dog welfare

Dog training methods range broadly from those using mostly positive punishment and negative reinforcement (aversive-based) to those using primarily positive reinforcement (reward-based). Although aversive-based training has been strongly criticized for negatively affecting dog welfare, there is no comprehensive research focusing on companion dogs and mainstream techniques, and most studies rely on owner-reported assessment of training methods and dog behavior. The aim of the present study was to evaluate the effects of aversive- and reward-based training methods on companion dog welfare within and outside the training context. Ninety-two companion dogs were recruited from three reward-based schools (Group Reward, n = 42), and from four aversive-based schools, two using low proportions of aversive-based methods (Group Mixed, n = 22) and two using high proportions of aversive-based methods (Group Aversive, n = 28). For evaluating welfare during training, dogs were video recorded for three sessions and six saliva samples were collected, three at home (baseline levels) and three after training (post-training levels). Video recordings were used to examine the frequency of stress-related behaviors (e.g., lip lick, yawn) and the overall behavioral state of the dog (e.g., tense, relaxed), and saliva samples were analyzed for cortisol concentration. For evaluating welfare outside the training context, dogs participated in a cognitive bias task. Results showed that dogs from Group Aversive displayed more stress-related behaviors, were more frequently in tense and low behavioral states and panted more during training, and exhibited higher post-training increases in cortisol levels than dogs from Group Reward. Additionally, dogs from Group Aversive were more 'pessimistic' in the cognitive bias task than dogs from Group Reward. Dogs from Group Mixed displayed more stress-related behaviors, were more frequently in tense states and panted more during training than dogs from Group Reward. Finally, although Groups Mixed and Aversive did not differ in their performance in the cognitive bias task nor in cortisol levels, the former displayed more stress-related behaviors and was more frequently in tense and low behavioral states. These findings indicate that aversive-based training methods, especially if used in high proportions, compromise the welfare of companion dogs both within and outside the training context.

Stress Response of Beagle Dogs to Repeated Short-Distance Road Transport

Simple Summary

In our study, we investigated how Beagle dogs that had not been transported before respond to transport by car. The stress-associated hormone cortisol, heart rate, white blood cells and the dogs’ behavior were analyzed. We hypothesized that transport is perceived as a stressor but dogs get used to it with repeated transports. The dogs were studied in their kennels, in a transport cage placed in a stationary vehicle and during repeated one and two-hour transports. Cortisol concentration increased during transports, and this increase was also evident when dogs were transported repeatedly. Additionally, changes in white blood cells indicated a stress response. Heart rate increased at the beginning of transports, independent from the dogs’ transport experience. During transports but also in the stationary vehicle, dogs were mostly sitting, and time spent standing decreased during experiments. Licking the mouth was the most frequent behavior during transports, but not in the stationary car. In conclusion, a transport-induced stress response was evident in dogs. There was no habituation with repeated transports, and transported dogs may suffer from motion sickness.

Abstract

This study aimed to characterize the response of transport-naïve dogs to one and two-hour road transports based on cortisol in saliva and blood plasma, heart rate, heart rate variability (HRV), neutrophil to lymphocyte (N/L) ratio and behavior. Two persons familiar to the dogs were present during transports and control experiments. We hypothesized that transport elicits a stress response, which decreases with repeated transports. Beagle dogs were allocated to three groups (n = 6 each). Group 1 served as control in the stable in week 1 and was transported for one hour in weeks 2, 3 and 4. Groups 2 and 3 served as controls in a non-moving vehicle and in the stable, respectively, in week 2. All three groups were transported for two hours in week 6. Cortisol concentration increased during transports (p < 0.001), and this increase remained constant with repeated transports. Cortisol release during two-hour transports was not affected by transport experience. Cortisol concentration increased twofold in plasma and eightfold in saliva, indicating an increase in free cortisol. The N/L ratio increased during transport (p < 0.05). Heart rate increased at the beginning of transport while HRV decreased (p < 0.001). Heart rate and HRV neither differed among weeks nor between animals with different transport experience. During transports, but also in the stationary vehicle, dogs were mostly sitting, and time spent standing decreased during experiments (p < 0.001). Licking the mouth was the most frequent behavior during transports but not in the stationary vehicle (p < 0.01). In conclusion, a transport-induced stress response was evident in dogs. There was no habituation with repeated transports, and transported dogs may suffer from motion sickness.

Evaluation of serum cortisol concentration as a prognostic indicator for nonsurvival to hospital discharge in critically ill dogs

OBJECTIVE

To investigate whether serum cortisol (SC) concentration is a useful prognostic indicator for survival versus nonsurvival to hospital discharge in critically ill dogs.

ANIMALS

229 client-owned dogs.

PROCEDURES

Medical records were retrospectively reviewed to identify critically ill dogs that were hospitalized between January 2010 and May 2018 and that had SC concentrations measured ≤ 3 days after admission. Results for SC concentrations were compared for dogs grouped by survival versus nonsurvival to hospital discharge, with versus without sepsis, and other variables of interest. The predictive value of SC concentration for nonsurvival to hospital discharge was assessed (OR, sensitivity, and specificity) for cutoffs determined from a ROC curve or reference limit.

RESULTS

Median SC concentration was higher in dogs that did not survive to hospital discharge (8.5 μg/dL; interquartile [25th to 75th percentile] range, 4.8 to 11.8 μg/dL), compared with concentration in those that were discharged alive (4.5 μg/dL; interquartile range, 2.5 to 6.9 μg/dL). The area under the ROC curve was 0.72 (95% confidence interval [CI], 0.64 to 0.81) for SC concentration predicting nonsurvival. The calculated optimum cutoff of SC concentration was 7.6 μg/dL, at which the OR, sensitivity, and specificity for nonsurvival were 5.4 (95% CI, 2.7 to 10.9), 58%, and 80%, respectively. Alternatively, when the upper reference limit for SC concentration (5.8 μg/dL) was used as the cutoff, the OR, sensitivity, and specificity for nonsurvival were 3.6 (95% CI, 1.8 to 7.1), 67%, and 64%, respectively.

CONCLUSIONS AND CLINICAL RELEVANCE

Results indicated that SC concentration could be used as part of an overall assessment of prognosis in critically ill dogs.

Who Is Pulling the Leash? Effects of Human Gender and Dog Sex on Human-Dog Dyads When Walking On-Leash

Simple Summary

The gender of humans and the sex of dogs influence human–dog interactions. This study investigated human–dog interactions when volunteers take shelter dogs for an on-leash walk, using video recording and a canine leash tension meter. Male dogs tended to pull more frequently and created higher leash tensions than female dogs. Dogs displayed more stress related behaviours when interacting with men than women, with the signs including spending less time holding the tail in a high position, and more frequent gazing and lip-licking behaviours. Finally, during the walk, there was a greater pre-disposition in women to use verbal commands and language typically associated with talking to babies, while men were more inclined to have physical contact with the dogs. These results may be used to match shelter dogs with appropriate men and women volunteers for dog walking exercise, and to improve potential socialisation of the dogs before rehoming.

Abstract

Previous studies have indicated that human gender and canine sex influences human–dog interactions. However, the majority of studies have considered the interaction when dogs were off-leash and the behavioural interactions when dogs are walked on a leash have not been addressed. This study investigated human–dog interactions when shelter volunteers take shelter dogs for an on-leash walk. Video records were made of 370 walks, involving 74 volunteers and 111 shelter dogs, and a leash tension meter was used to determine the pull strength of dogs and walkers. Human gender and canine sex had dyadic effects during the walk. Male dogs tended to pull more frequently and created increased leash tensions. Dogs displayed more stress related behaviours when interacting with men than women, with the signs being spending less time holding the tail in the high position, and more frequent gazing and lip-licking behaviours. Finally, there was a greater pre-disposition in women to use verbal commands, and language typically used with babies, while men were more inclined to have physical contact with dogs. This study’s results may be used to match shelter dogs with appropriate men and women volunteers for walking exercise of the dog, and to improve potential dog socialisation efforts by shelters.

Fear expressions of dogs during New Year fireworks: a video analysis

A high proportion of pet dogs show fear-related behavioural problems, with noise fears being most prevalent. Nonetheless, few studies have objectively evaluated fear expression in this species. Using owner-provided video recordings, we coded behavioural expressions of pet dogs during a real-life firework situation at New Year’s Eve and compared them to behaviour of the same dogs on a different evening without fireworks (control condition), using Wilcoxon signed ranks tests. A backwards-directed ear position, measured at the base of the ear, was most strongly associated with the fireworks condition (effect size: Cohen’s d = 0.69). Durations of locomotion (d = 0.54) and panting (d = 0.45) were also higher during fireworks than during the control condition. Vocalisations (d = 0.40), blinking (d = 0.37), and hiding (d = 0.37) were increased during fireworks, but this was not significant after sequential Bonferroni correction. This could possibly be attributed to the high inter-individual variability in the frequency of blinking and the majority of subjects not vocalising or hiding at all. Thus, individual differences must be taken into account when aiming to assess an individual’s level of fear, as relevant measures may not be the same for all individuals. Firework exposure was not associated with an elevated rate of other so-called ‘stress signals’, lip licking and yawning.

Evaluation of salivary vasopressin as an acute stress biomarker in healthy dogs with stress due to noise and environmental challenges

Background

Stress is associated with various detrimental changes in physiological health that affect an animal’s quality of life. The hypothalamus-pituitary-adrenal (HPA) axis and the sympathetic-adreno-medullar (SAM) axis are two main physiological pathways that constitute the stress response of an organism. Arginine vasopressin (AVP) is a mediator of the HPA axis and is known to be related to social behaviours and stress. The serum concentration of AVP is higher in more aggressive dogs and humans with post-traumatic stress disorder. Salivary biomarker analysis is a non-invasive method to assess stress. The purpose of this study was to evaluate the possibility of using salivary AVP as an acute stress biomarker in dogs. Salivary AVP concentration was measured before and after exposure to all relevant environmental stimuli (i.e. car trip to the lab, physical examination by the veterinarian, and sampling procedure,) and then after 30 min of vacuum noise exposure. Behavioural assessments, physiologic parameter assessments, and serum cortisol analysis were conducted in combination. Statistical analysis was conducted separately in the total study population, the less stressed group, and the more stressed group, respectively.

Results

Based on stress behaviour analysis scores, 28 dogs were classified into less or more stressed groups. All four physiologic parameters (blood pressure, body temperature, heart rate, and respiratory rate) were significantly increased after noise and environmental challenges, in the more stressed group. Serum cortisol did not show any significant change. Salivary AVP significantly decreased after noise and environmental stimulation in the more stressed group but not in the less stressed group. Salivary AVP and blood pressure changes were negatively correlated in the more stressed group.

Conclusion

Salivary AVP may be a potential acute stress biomarker in dogs.

Selecting Dogs for Explosives Detection: Behavioral Characteristics

Detection dogs are widely considered the most effective and adaptive method for explosives detection. Increases in emerging sophisticated threats are accelerating the demand for highly capable explosives detection, causing a strain on available supplies of quality canines worldwide. These strains are further compounded by rigorous behavioral standards required to meet mission-specific capabilities, leading to high rates of dogs disqualified from training or deployment. Ample research has explored the behavioral characteristics important for assistance, guide, and other traditional working roles, while those corresponding to more specialized tasks such as detection of explosives are not as well-understood. In this review we aim to identify the behavioral characteristics important for operational tasks of explosives detection dogs, contrasting with that of other working roles and highlighting key differences between explosives and other types of detection dogs. Further, we review the available research on methods for assessing and selecting candidate detection dogs and make recommendations for future directions and applications to the industry. Improvements and standardization in assessment technology allowing for the identification and enhancement of behavioral characteristics will be key to advancing canine detection technology in general.

Surgical and Behavioral Relationships With Welfare

Veterinarians perform surgery for a number of reasons, from treating a problem to preventing future problems. There is an inextricable link between the physical and psychological aspects of an animal's health, and surgery is often a conduit to bridge that gap. Some surgical procedures can affect an animal's behavior, such as castration, and some pose an ethical dilemma, such as ear cropping and declawing. Ameliorating pain, decreasing stressful experiences for the animal, and identifying and treating concurrent problem behaviors are hallmarks of improving animal welfare. The purpose of this article is to outline some of these interrelationships and ethical dilemmas, providing evidence-based verification as applicable.

Evaluation of stress status using the stress map for guide dog candidates in the training stage using variations in the serum cortisol with nerve growth factor and magnesium ions

Most studies on guide dogs for the blind were conducted to investigate the appropriateness of the animals, including in terms of their breeding, constitution, and temperament. However, research to comprehend the stress status of guide dog candidates in response to their training has been unclear. In this study, the levels of serum cortisol, nerve growth factor (NGF), and magnesium ion (Mg²⁺) levels of guide dog candidates during the three training stages-the elementary, intermediate, and advanced classes-were examined. Dogs were classified based on the contents of the classes and period during the training in which they were subjected. Since the dogs in the elementary class had the lowest serum NGF and Mg²⁺ levels, they were understood to be under mental stress and to be unfamiliar with their new surroundings. In contrast, the serum NGF and Mg²⁺ levels were high in the dogs in the advanced class, though they were demonstrated to be mentally stable and acclimated to their environment. Additionally, they were almost free from the stress caused by daily life, since they had the lowest serum cortisol levels. The status of each dog was plotted on a map consisting of 2 axes representing the serum NGF and Mg²⁺ levels with high or low cortisol levels. Plots could be divided into three domains corresponding to the elementary, intermediate, and advanced classes. Therefore, for working dogs, serum NGF and Mg²⁺ levels in addition to serum cortisol levels may be important factors to comprehend the type of stress situation that each dog was in.

Efficacy of Dog Training With and Without Remote Electronic Collars vs. a Focus on Positive Reinforcement

We assessed the efficacy of dog training with and without remote electronic collars compared to training with positive reinforcement. A total of 63 dogs with known off-lead behavioral problems such as poor recall were allocated to one of three training groups (each n = 21), receiving up to 150 min of training over 5 days to improve recall and general obedience. The 3 groups were: E-collar—manufacturer-nominated trainers who used electronic stimuli as part of their training program; Control 1—the same trainers following practices they would apply when not using electronic stimuli; and Control 2—independent, professional trainers who focused primarily on positive reinforcement for their training. Data collection focused on dogs' response to two commands: “Come” (recall to trainer) and “Sit” (place hindquarters on ground). These were the two most common commands used during training, with improving recall being the target behavior for the subject dogs. Measures of training efficacy included number of commands given to elicit the response and response latency. Control 2 achieved significantly better responses to both “Sit” and “Come” commands after a single instruction in the allocated time. These dogs also had shorter response latencies than the E-collar group. There was no significant difference in the proportion of command disobeyed between the three groups, although significantly fewer commands were given to the dogs in Control 2. There was no difference in the number of verbal cues used in each group, but Control 2 used fewer hand and lead signals, and Control 1 made more use of these signals than E-collar group. These findings refute the suggestion that training with an E-collar is either more efficient or results in less disobedience, even in the hands of experienced trainers. In many ways, training with positive reinforcement was found to be more effective at addressing the target behavior as well as general obedience training. This method of training also poses fewer risks to dog welfare and quality of the human-dog relationship. Given these results we suggest that there is no evidence to indicate that E-collar training is necessary, even for its most widely cited indication.

The influence of human interaction on guinea pigs: Behavioral and thermographic changes during animal-assisted therapy

Guinea pigs are often involved in animal-assisted therapy (AAT) but there is little knowledge about the effects of human contact on guinea pigs involved in AAT. The aim of this study was to investigate effects of availability of a retreat, presence of conspecifics, prior experience with AAT, and human interaction on indicators of welfare in guinea pigs involved in AAT. Guinea pigs of both sexes and different ages (n=20) were assigned to a randomized, controlled within-subject trial with repeated measurements. Each guinea pig was tested in four settings: (I) therapy with retreat possibility with conspecifics, (II) therapy with retreat possibility without conspecifics, (III) therapy without retreat possibility, and (IV) setting without human interaction. We measured changes in eye temperature, as a proxy to infer stress levels, at 5-s intervals with a thermographic camera. All sessions were video recorded and the guinea pigs' behavior was coded using continuous recording and focal animal sampling. For the statistical analysis we used generalized linear mixed models, with therapy setting as a fixed effect and individual guinea pig as a random effect. We observed a temperature increase relative to baseline in settings (I) therapy with retreat with conspecifics present and (III) therapy without retreat. The percentage of time a guinea pig was petted was positively correlated with a rise in the eye temperature independent of the setting. Time spent eating was reduced in all therapy settings (I-III) compared to the setting without HAI (human animal interaction) (IV). In the setting with retreat (I), guinea pigs showed more active behaviors such as locomotive behavior or startling compared to the setting without retreat (III) and the setting without HAI (IV). When no retreat was available (III), they showed more passive behaviors, such as standing still or freezing compared to therapy with retreat (I). Based on our results we identified the behaviors "reduced eating", "increased startle" and "increased freezing" as indicators of an increased stress level. Petting the guinea pigs was correlated with a rise in the eye temperature and might be a factor which can cause stress. Our results support the suggestion that guinea pigs involved in AAT should have a retreat possibility, should have access to conspecifics, and should be given time to adapt to a new setting. In this way, stress might be reduced.

Salivary cortisol as a marker of acute stress in dogs: a review

Public interest in the welfare of domestic dogs has increased in recent years. Dogs under human care should experience as little stress as possible, and as such it is necessary to measure and quantify their levels of stress. Stress parameters that can be measured noninvasively may help to identify the poor welfare of animals. This review aimed to determine whether and under what conditions the hormone cortisol in dog saliva can be used as a noninvasive acute stress marker. The use of salivary cortisol as a stress marker has some disadvantages, which can lead to data misinterpretations. A key factor is the standardized method of sampling and subsequent processing before analysis. In addition, possible circadian alternation and individual variability of cortisol hormone levels should be consistently considered during the preparation of the experimental scheme, statistical data processing and final interpretation of the results. Because of the complex nature of the stress response, the observation of salivary cortisol should be supplemented with behavioral observations, but it should be noted that behavioral stress symptoms may not always be positively correlated with stress hormone production. Besides behavioral observations, it is advisable to supplement the measurement of cortisol by other salivary stress markers of sympathetic-adrenal-medullary and hypothalamic-pituitary-adrenal pathways. This comprehensive assessment of the stress impact on the individual will enable one to characterize the level and type of stress.

Dogs' Stay in a Pet Hotel - Salivary Cortisol Level and Adaptation to New Conditions

The aim of this study was to assess salivary cortisol level in dogs during admission and a three-day stay in a pet hotel. The study involved 20 dogs admitted to a pet hotel for a stay lasting for at least three consecutive days. The study group consisted of 10 small dogs and 10 medium-sized dogs, eight females and 12 males. Saliva was collected each day to assess cortisol levels. A stay in a hotel is a stressful situation for dogs, as evidenced by the increase in the salivary cortisol level. The highest salivary cortisol level was observed on the day of admission to the hotel. The median salivary cortisol level in the dogs on the consecutive days was 2.7 ng/ml on admission, 2.1 ng/ml after 24 hours, and 1.9 ng/ml after 48 hours. Depending on the size of the dog, the median salivary cortisol level was 2.8 ng/ml, 2.9 ng/ml and 2.4 ng/ml in the small dogs and and 2.2 ng/ml, 1.7 ng/ml and 1.2 ng/ml in the medium sized dogs on the consecutive days.

Effects of Stroking on Salivary Oxytocin and Cortisol in Guide Dogs: Preliminary Results

This pilot study aimed at investigating how salivary oxytocin levels are affected by human interaction and isolation in eight guide dogs (six Labrador retrievers and two golden retrievers; four males and four females, 21.87 ± 1.36 months old) just before assignment to the blind person. Each dog engaged, at one-week intervals, in a positive (5 min of affiliative interaction with their trainer) and a negative (5 min of isolation) condition. Saliva samples used for Enzyme Immunoassay (EIA) quantification of salivary oxytocin were collected before and immediately after both experimental conditions. In order to assess potential hypothalamic pituitary adrenal (HPA) axis activation that could have affected oxytocin levels, saliva samples were collected 15 min after both experimental conditions for EIA quantification of salivary cortisol and a behavioral assessment was performed during the negative condition. The results were compared using the Wilcoxon test (p < 0.05). Oxytocin concentrations showed a statistically significant increase after the positive interaction (p = 0.036) and no difference after the negative one (p = 0.779). Moreover, no difference (p = 0.263) was found between the cortisol concentrations after each experimental condition and no signs of distress were observed during the isolation phase. These preliminary findings support the hypothesis that stroking dogs has positive effects on their emotional state independently of hypothalamic pituitary adrenal axis activation.

Fears from the past? The innate ability of dogs to detect predator scents

Throughout the animal kingdom, antipredator mechanisms are an evolutionary driving force to enable the survival of species classified as prey. Information regarding a predator's location can be determined through chemosensory cues from urine, faeces, visual and/or acoustic signals and anal gland secretions; and in several lab and field-based studies it has been seen that these cues mediate behavioural changes within prey species. These behaviours are often linked to fear and avoidance, which will in turn increase the prey's survival rate. In many studies dogs (Canis lupus familiaris) have been used as a predator species, however, no research has addressed a dog's innate ability to detect predator scents, hence the rationale behind this study. We assessed the innate ability of the untrained domestic dog to detect faecal scents of wild Eurasian brown bear (Ursus arctos arctos) and European lynx (Lynx lynx). The study monitored 82 domestic dogs across the UK and Norway. The dogs were exposed to the two predator faecal scents from Eurasian brown bear and European lynx, a herbivore faecal scent of Eurasian beaver (Castor fiber) and water control. Measurements were taken upon the time spent within a 40 cm radius of each scent and changes in the dog's heart rate when within this 40 cm radius. We found dogs spent a decreased length of time around the predator scents and had an increased heart rate in relation to their basal heart rate. We conclude that dogs can innately sense predator scents of brown bear and lynx and elicit fear towards these odours, as shown through behavioural and physiological changes.

Salivary Cortisol Interactions in Search and Rescue Dogs and their Handlers

Simple Summary

Stress affects both people and animals every day. Working dogs are exposed to the same stressors as their handlers during work. Our research was conducted during search and rescue dog exams. The aim of the study was to investigate if handler stress during the exam affects his or her dog’s stress level. We observed a strong relationship of salivary cortisol between the dogs and their handlers, which was most prevalent in female dogs and female handlers.

Abstract

Search and rescue dogs are an important link in the search for missing persons. The aim of the study was to assess exam stress in search and rescue dogs and their handlers. The study included 41 rescue teams taking exams of field and rubble specialties. The level of cortisol, which is the main glucocorticosteroid modulating stress reactions in humans and dogs, was analyzed. The biological material used to assess the hormone concentration was saliva collected in a non-invasive way. In total, 164 test samples were collected: two from the dog and two from the handler before and immediately after the exam. Rescue exams were shown to significantly increase salivary cortisol in both dogs and their handlers. Strong interactions between cortisol levels in human–dog teams were also found with a more pronounced effect in female dog–female handler dyads.

Effects of Olfactory and Auditory Enrichment on the Behaviour of Shelter Dogs

Shelter environments are stressful for dogs, as they must cope with many stimuli over which they have little control. This can lead to behavioural changes, negatively affect their welfare and downgrade the human-animal bond, affecting re-homing success. Arousal is evident in their behaviour, particularly increased activity and frequent vocalisation. Environmental enrichment plays an important role in reducing arousal behaviour, either through direct physiological effects or by masking stressful stimuli. The present study focused on sensory environmental enrichment, using olfactory and auditory stimuli under shelter conditions. Sixty dogs were allocated to one of four treatments: three types of enrichment, Lavender, Dog appeasing pheromone (DAP) and Music, and a Control group. Stimuli were applied for 3 h/d on five consecutive days. Dogs exposed to DAP lay down more, and those exposed to Music lay down more with their head down, compared to the Control. Those in the Control stood more on their hind legs with their front legs on the exit door, compared to those exposed to Music and DAP, particularly if they had only been in the shelter for a short time. They also panted and vocalised much more than dogs in the three enrichment treatments, which tended to persist during the 4 h period post treatment, and in the case of vocalisation into the subsequent night. The study suggests that all three enrichments had some positive benefits for dogs in shelters, as well as being non-invasive and easy to apply in the shelter environment.

Intraspecific Motor and Emotional Alignment in Dogs and Wolves: The Basic Building Blocks of Dog-Human Affective Connectedness

Involuntary synchronization occurs when individuals perform the same motor action patterns during a very short time lapse. This phenomenon serves an important adaptive value for animals permitting them to socially align with group fellows thus increasing integration and fitness benefits. Rapid mimicry (RM) and yawn contagion (YC) are two behavioral processes intermingled in the animal synchronization domain. Several studies demonstrated that RM and YC are socially modulated being more frequently performed by individuals sharing close relationships. This evidence highlights the relation between RM/YC and emotional contagion that is the capacity of two or more individuals to share the same affective state. In this review, we try to delineate a possible developmental trajectory of emotional sharing phenomena by using, as a model species, the domestic dog (Canis lupus familiaris), a valid example of empathic predisposition towards individuals belonging both to the same and the different species. We contrast available findings on RM and YC in dog-dog and dog-human dyads with those in wolf-wolf dyads, in order to investigate if the ability to emotionally engage with conspecifics (wolf-wolf and dog-dog) is evolutionary rooted in canids and if provides the basis for the development of inter-specific emotional sharing (dog-human).

Communicative roots of complex sociality and cognition

Mammals living in more complex social groups typically have large brains for their body size and many researchers have proposed that the primary driver of the increase in brain size through primate and hominin evolution was the selection pressures associated with sociality. Many mammals, and especially primates, use flexible signals that show a high degree of voluntary control and these signals may play an important role in forming and maintaining social relationships between group members. However, the specific role that cognitive skills play in this complex communication, and how in turn this relates to sociality, is still unclear. The hypothesis for the communicative roots of complex sociality and cognition posits that cognitive demands behind the communication needed to form and maintain bonded social relationships in complex social settings drives the link between brain size and sociality. We review the evidence in support of this hypothesis and why key features of cognitively complex communication such as intentionality and referentiality should be more effective in forming and maintaining bonded relationships as compared with less cognitively complex communication. Exploring the link between cognition, communication and sociality provides insights into how increasing flexibility in communication can facilitate the emergence of social systems characterised by bonded social relationships, such as those found in non-human primates and humans. To move the field forward and carry out both within- and among-species comparisons, we advocate the use of social network analysis, which provides a novel way to describe and compare social structure. Using this approach can lead to a new, systematic way of examining social and communicative complexity across species, something that is lacking in current comparative studies of social structure.

Do dogs rescue their owners from a stressful situation? A behavioral and physiological assessment

Rescue behavior is considered a type of pro-social response, defined as a voluntary action directed to benefit another individual who is in a stressful or dangerous situation. In two experiments, we investigated whether dogs would rescue their owners when the person was trapped inside a wooden box and emitted clear signs of stress. The performance of these dogs was compared against that of a control group in which the owners remained calm while trapped. In addition, to assess if training modulated this behavior, we tested a group of dogs from the military trained in search and rescue tasks (Experiment 1). Results showed that dogs opened the box more frequently when the owner pretended to be stressed than when calm. Training shortened latencies to open the door but not the frequency of the behavior. In Experiment 2, we investigated if emotional contagion could be a possible mechanism underlying dogs' rescue responses by measuring dogs' behavior, heart rate, and saliva cortisol level in the stressed and calm conditions, and also controlled for obedience by having the calm owners call their pets while trapped. We replicated the findings of Experiment 1 as more dogs opened the door in the stressed owner condition than in the calm condition. In addition, we observed an increase in heart rate across trials in the stressed condition and a decrease across trials in the calm condition, but no differences in cortisol levels or stress-related behaviors between conditions. In brief, we found evidence that approximately half of the dogs without previous training showed spontaneous rescue behaviors directed to their owners. Neither was this behavior motivated by obedience nor by the motivation to re-establish social contact with the owner. We conclude that emotional contagion is a plausible mechanism underlying dogs' rescue behavior in the present protocol.

Detection of Impending Aggressive Outbursts in Patients with Psychiatric Disorders: Violence Clues from Dogs

Aggression in psychiatric wards is a continuing matter of concern for both patients and medical staff. Here we have tested the hypothesis that the frequency of such incidents can be reduced with a new strategy of using trained alert dogs that warn of impending violent outbursts. Dogs were positioned among patients in psychiatric wards. Analyses show that the dogs warned of impending aggressive outbursts, responding to signals from a specific patient out of a group of unfamiliar psychotic patients. Their alerts were not a response to stress as canine cortisol levels were not significantly changed. Visual glance was the preferred method used by young dogs to respond to patient. Until a similar electronic technology is developed, trained alert dogs can help caregivers to protect both the patient and those around them from injuries that may otherwise result from aggressive outbursts in psychiatric patients.

Changes in Saliva Analytes Correlate with Horses' Behavioural Reactions to An Acute Stressor: A Pilot Study

Simple Summary

Emotionality is an individual characteristic defined as the propensity to respond to stress-inducing stimuli such as fear-inducing objects or social separation. Evaluation of emotionality in horses is important as it may impact their learning performance. Although emotionality is usually assessed by measuring behavioural patterns, biomarkers could provide additional information about stress response, especially with respect to its temporal dynamics. In this study, behavioural responses were measured as well as a panel of salivary biomarkers related to stress, including salivary alpha-amylase, lipase, total esterase, butyrylcholinesterase, adenosine deaminase, and cortisol, in riding horses after acute experimental stress (the sudden opening of an umbrella). We found significant changes in most of the salivary biomarkers evaluated after the induced stress, where increases in butyrylcholinesterase were more closely related to behavioural responses to acute stress and low salivary alpha-amylase values were more closely related to quietness behaviours. Therefore, this preliminary research provides information about the relationship between behaviour patterns and biomarkers of stress in saliva in horses, and opens the possibility of wider use of selected biomarkers in saliva, such as butyrylcholinesterase or alpha-amylase, for the evaluation of acute stress in horses.

Abstract

Acute stress induces an array of behavioural reactions in horses that vary between individuals. Attempts to relate behavioural patterns and physiological responses have not always given clear-cut results. Here, we measured the changes in a panel of salivary components: salivary alpha-amylase (sAA), lipase, total esterase (TEA), butyrylcholinesterase (BChE), adenosine deaminase (ADA), and cortisol, and their potential link with horses’ behaviours after acute stress. Saliva samples were collected in nine riding horses subjected to a test consisting of opening an umbrella. Saliva sampling was obtained at a basal time point in the stall (T1), in the test indoor arena (T2), at a time of stress (T3), and 30 min (T4) and 60 min (T5) later. The horses’ behaviour was recorded at T3 for 1 min. sAA, lipase, TEA, and BChE showed significant changes along time, increasing at T3 for BChE, and decreasing at T4 for sAA and BChE. Butyrylcholinesterase appeared to be the most reliable predictor of behavioural responses, as it correlated with the index of emotionality, of laterality, and the occurrence of alarm signals, while sAA decreased when horses expressed quieter behaviours. These first results bring promising lines for novel, more precise physiological markers of acute stress in horses that can bridge the gap between behaviour and physiology.

Effect of a Standardized Four-Week Desensitization and Counter-Conditioning Training Program on Pre-Existing Veterinary Fear in Companion Dogs

Many dogs show signs of fear during veterinary appointments. It is widely recommended to use desensitization and counter-conditioning training to reduce this fear. However, the efficacy of this method for reducing veterinary fear has not been examined. We assessed the effect of a standardized four-week training program on behavioural and physiological signs of fear in dogs with pre-existing veterinary fear. Owned dogs were randomly allocated to receive training (n = 15) or no training (n = 22; Control). Owners of dogs in the training group were instructed to perform exam-style handling on their dog and to visit the veterinary clinic weekly. Owners of control dogs were given no instructions. Fear responses were assessed before and after the training period by a blinded observer during clinic arrival and examination. Despite motivated owners volunteering to participate in the current study, 44% of owners were non-compliant to this training program. During examination, control dogs had higher odds (95% confidence Interval (CI)) of reduced posture compared to trained dogs (Odds ratio (OR): 3.79, CI: 1.03-16.3). Fear scores for trained dogs lowered during the second examination (p = 0.046), and 86.7% of dog owners reported a reduction in their dog's fear levels across the training period (p = 0.007). When entering the clinic (p = 0.002) and during examination (p = 0.002), trained female dogs had a higher rate of lip licking than control females. The training program did not influence temperature, heart rate, respiratory rate, avoidance, trembling, vocalizations, or willingness and encouragement to step on the scale. Results suggest that this four-week training program was mildly effective at reducing veterinary fear in dogs. Further research is necessary to explore the efficacy of longer, more intensive, and individualized training programs.