Behavioural and physiological reactions of piglets to gentle tactile interactions vary according to their previous experience with humans

Horses' Tactile Reactivity Differs According to the Type of Work: The Example of Equine-Assisted Intervention

Tactile perception in humans varies between individuals and could depend on extrinsic factors such as working activity. In animals, there is no study relating the influence of animals' work and their tactile reactivity per se. We investigated horses' tactile reactivity using von Frey filament in different body areas and compared horses working only in equine-assisted interventions (EAI), in riding school (RS) lessons, and in both activities (EAI-RS). We further compared tactile actions by people with or without mental and/or developmental disorders during brushing sessions. The results indicated that EAI horses showed higher tactile reactivity compared to EAI-RS and RS horses, both in terms of number of reactions overall, and especially when the test involved thin filaments. All horses showed high tactile reactivity when tested on the stifle, and this was particularly true for EAI horses. These differences could be related to humans' actions, as participants diagnosed with disorders brushed more the hindquarters and showed more fragmented actions. This study opens new lines of thought on the influence of EAI working activity on horses' tactile reactivity, and hence, on horses' sensory perception. Tactile reactivity outside work, may be directly (via tactile stimulations) or indirectly (via the welfare state), influenced by working conditions.

Long-term body tactile stimulation reduces aggression and improves productive performance in Nile tilapia groups

One concern of the Anthropocene is the effects of human activities on animal welfare, revealing the urgency to mitigate impacts of rearing environments. Body tactile stimulation (TS), like massage therapy, has emerged as an enrichment method to counteract stress and anxiety in vertebrates. In the current study, we evaluated the effects of long-term TS on four-member groups of male Nile tilapia, a worldwide reared species whose socially aggressive behavior is an essential source of stress. We placed a rectangular PVC frame fitted with vertical plastic sticks sided with silicone bristles in the center of aquarium to enable the fish to receive body TS when passing through the bristles. A similar apparatus without bristles was used as the control. Fish subjected to TS for 21 days showed a gradual lowering of overt fights over time, but with no reduction in cortisol or androgen levels. Nevertheless, TS improved the specific growth rate, maintained balanced length/weight gain, and increased feed efficiency, probably owing to the lowered energy expenditure during fights. Thus, we show for the first time that long-term TS provided by a simple device can be used as a tool to improve the welfare and productive performance of territorial fish.

The Effect of Demonstrator Social Rank on the Attentiveness and Motivation of Pigs to Positively Interact with Their Human Caretakers

Simple Summary

Motivation to express a socially learned behavior can be inhibited or facilitated by the presence of socially dominant individuals, who often attract greater attention from their conspecifics. This study investigated whether experienced pigs (termed “demonstrators”) of higher rank attract greater attention from their pen mates when they are observed from behind an acrylic panel while being gently handled by the stockperson. We also investigated whether the presence of a demonstrator pig of different social rank, who previously established a positive relationship with the stockperson in presence of conspecifics, affects the motivation and behaviors of their pen mates to positively interact with humans. Our results show that during the gentle handling of the demonstrator, there was an overall preference for observer pigs to visually attend to the dominant demonstrators more than the low-ranking demonstrators. Furthermore, our study shows that the proximity of a dominant demonstrator pig interfered with the motivation of their pen mates to positively interact with the stockperson, whereas the presence of a subordinate demonstrator facilitated the expression of a greater affinity toward the human, resulting in longer physical contact, and a higher percentage of accepted strokes. These findings reveal that social dynamics and dominance rank have a strong effect on the attentional state and the facilitation and inhibition of social behaviors in domestic pigs.

Abstract

In this study, we addressed the social attentiveness, as well as the phenomenon of social facilitation and inhibition in the context of a positive human–pig relationship. Specifically, we investigated whether the social rank of an experienced pig (termed “demonstrator”) has an effect on the attentiveness of the remaining pen mates (N = 40) when they observe the demonstrator being gently handled by a stockperson from behind an acrylic panel. We found that pigs preferentially attended to dominant demonstrators rather than subordinate demonstrators during their gentle handling sessions with the stockperson. Additionally, we also examined whether the presence of a demonstrator pig of different social rank, who previously established a positive relationship with the stockperson in presence of conspecifics, affects the behavior and motivation of their pen mates to positively interact with the stockperson. To test for the effect of the presence and demonstrator’s social rank on pen mate interactions with the stockperson, we evaluated the behavior of domestic pigs (N = 65) toward the stockperson using a human-approach test in their home-pen. Pigs showed a decrease in their motivation to positively interact with the stockperson when a socially dominant demonstrator was present, behaving similarly to animals receiving minimal human contact (control group). Overall, they exhibited a greater latency to physical contact, a lower acceptance of stroking, and spent more time looking at the stockperson compared to pigs exposed to subordinate demonstrators. Taken together, these findings expand our current understanding of pigs’ cognition and social behavior, and the nature of social attention bias in farm animals. Our findings indicate that positive handling of previously selected subordinate demonstrators seems to be the best strategy to reduce the level of fear in large groups of pigs.

Positive Human Contact and Housing Systems Impact the Responses of Piglets to Various Stressors

Simple Summary

Early life experiences such as contact with humans, maternal care and the physical environment can play a substantial role in shaping behavioural and physiological responses to stress. This experiment studied the effects of lactation housing systems and human interaction on stress in young pigs. We hypothesised that piglets handled in a positive manner and reared in loose farrowing and lactation pens with increased opportunity for interaction with their dam, greater space and more complexity in their physical environment have improved stress resilience than piglets reared in traditional farrowing crates with routine contact from stockpeople. In both housing systems, providing regular opportunities for positive human interaction reduced piglets’ fear of humans and routine husbandry procedures imposed by humans, and reduced the number of injuries obtained after weaning. However, contrary to the expected findings, piglets from loose farrowing and lactation pens were more reactive to capture by a stockperson, more fearful of novel and human stimuli, had more injuries during the lactation period and were more likely to perform behaviours which may be indicative of reduced coping after weaning. Whether these effects are specific to the loose farrowing and lactation system studied in this experiment or are reflective of other loose systems requires further research.

Abstract

This experiment studied the effects of lactation housing systems and human interaction on piglets’ responses to routine stressors. Forty litters of piglets were reared in either a standard farrowing crate (FC) or a loose farrowing and lactation pen (LP; PigSAFE pen) and received either routine contact with humans (C) or regular opportunities for positive human contact (+HC; 3 min of patting, stroking and scratching 5 times/week). Behavioural and physiological responses to routine husbandry procedures, weaning, novelty and humans were studied in addition to effects on piglet growth, injuries and survival. Compared to C piglets, +HC piglets vocalised for shorter durations (p = 0.018) during husbandry procedures and showed a lower intensity of escape behaviour during iron injection (p = 0.042) and oral vaccination (p = 0.026) at 3 d of age, capture at 2 wk of age (p < 0.001), and intramuscular vaccination (p = 0.005) at 3 wk of age. +HC piglets at 2 wk of age were faster than C piglets to approach (p = 0.048) and interact (p = 0.042) with a stationary unfamiliar human. Compared to LP piglets, FC piglets showed a lower intensity of escape behaviour during capture and iron administration by a stockperson at 3 d of age (p = 0.043). FC piglets at 2 wk of age were faster than LP piglets to approach (p = 0.005) and interact (p = 0.027) with a novel object and approach (p = 0.009) and interact (p = 0.008) with an unfamiliar human. FC piglets had fewer injuries than LP piglets at 2 wk of age (p = 0.004). +HC pigs had fewer injuries than C pigs after weaning (p = 0.003). After weaning there were more pigs from LP than FC observed to be upright (both stationary, p = 0.002 and walking, p = 0.024), vocalizing (p = 0.004), nosing another pig (p = 0.035) and nosing the pen floor (p = 0.038). There were no significant effects on neutrophil:lymphocyte ratios or plasma cortisol concentrations 1.5 h after weaning. However, 25 h after weaning +HC pigs had higher haptoglobin concentrations than C pigs (p = 0.002), and C/LP pigs had higher cortisol concentrations than +HC/LP and C/FC pigs (p = 0.012). There were no significant effects on piglet growth, the number of piglets born alive or the number stillborn, however there were more piglets weaned from FC than LP (p = 0.035). The results from this experiment raise questions that require further research on the ability of pigs reared in loose pens to cope with stressors such as exposure to humans, novelty, husbandry procedures and weaning. This experiment also provides evidence that regular positive human interaction reduces pigs’ fear of humans and husbandry procedures imposed by stockpeople. More research is required to determine if any of these effects are sustained long-term.

Effects of Positive Human Contact during Gestation on the Behaviour, Physiology and Reproductive Performance of Sows

Simple Summary

Stress can compromise animal welfare and impact the productivity of farm animals. In intensive production systems where close interactions between stockpeople and animals occur regularly, human contact of a positive nature may facilitate stress resilience. This experiment studied the effects of human interaction on stress in pigs, by providing sows in their home pens with either regular positive handling by stockpeople or routine human contact. Stress resilience was studied by assessing the behaviour, physiology and productivity of pigs in these two treatments. Positive human contact was effective at reducing the fear responses of sows towards stockpeople conducting routine husbandry practices in the home pens. However, the positive handling treatment did not affect the behaviour of pigs towards other stressors imposed outside of the home pen, acute or basal physiological measures of stress or reproductive performance. Sows receiving positive handling showed reduced physical interaction with the stockpeople delivering the treatment over time, which may indicate habituation to the novel or possible rewarding elements of the human contact treatment. This work confirms that regular positive interaction with stockpeople does reduce the fear of sows to stockpeople, but does not always confer stress resilence.

Abstract

Previous positive interactions with humans may ameliorate the stress response of farm animals to aversive routine practices such as painful or stressful procedures, particularly those associated with stockpeople. We studied the effects of positive handling by providing younger (parity 1–2) and older (parity 3–8) sows housed in pens of fifteen (n = 24 pens in total) with either positive human contact (+HC) or routine human contact (control) during gestation. The +HC treatment involved a familiar stockperson patting and scratching sows and was imposed at a pen-level for 2 min daily. Measurements studied included behavioural, physiological and productivity variables. The +HC sows showed reduced avoidance of the stockperson conducting pregnancy testing and vaccination in the home pens, however the behavioural and cortisol responses of sows in a standard unfamiliar human approach test did not differ. There were no effects of +HC on aggression between sows, serum cortisol or serum brain-derived neurotrophic factor concentrations during gestation, or on the behavioural and cortisol response to being moved to farrowing crates. There were also no effects of +HC on the maternal responsiveness of sows, farrowing rate or the number of piglets born alive, stillborn or weaned. Sows in the +HC pens reduced their physical interaction with the stockpeople imposing the treatment after 2 weeks, which suggests the sows may have habituated to the novel or possible rewarding elements of the handling treatment. This experiment shows that regular positive interaction with stockpeople does reduce sows’ fear of stockpeople, but does not always confer stress resilence.

Do Domestic Pigs Acquire a Positive Perception of Humans through Observational Social Learning?

Farm animals can perceive humans positively by observing another animal being positively handled. This study evaluated whether pigs acquire a positive perception of humans after observing either a high or low socially ranked conspecific receiving gentle handling. Seventy-five 21-week-old pigs were housed in 15 nursery pens (five pigs/pen) and randomly assigned to one of three pen treatments: Dominant Demonstrator Group (DDG), Subordinate Demonstrator Group (SDG) and Control Group (CG). Pigs from DDG and SDG observed a high and low socially ranked conspecific ("demonstrator"), respectively, while the demonstrator received gentle stroking and a sucrose solution for 10 min, twice a day for 5 weeks. Control group pigs received minimal human contact. Following treatment, the behavior and heart rate variability of non-demonstrator pigs were evaluated in response to a stockperson in an open-field test. Pigs from the DDG and SDG contacted the stockperson sooner (p < 0.001), spent more time investigating the stockperson (p < 0.05), accepted more stroking (p < 0.001) and exhibited a lower low/high frequency ratio (p = 0.015) compared to the CG. No differences in learning between the pigs from the DDG and SDG were found. These results suggest that pigs can learn to perceive humans positively through observational social learning, regardless of the demonstrator conspecific's social rank.

The Stockman's Scorecard: quantitative evaluation of beef cattle stockmanship

An animal’s action, or inaction, is the direct result of a stockman’s action or inaction. The Stockman’s Scorecard is a novel observation instrument that has been proven to be a valid and reliable tool to measure the quality of beef cattle stockmanship. Specific handler actions have been weighted based on their perceived negative relationship to cattle stress from handling. The purpose of this article is to 1) document the initial use of the scorecard in a beef cattle feedlot setting and 2) provide further support to its validity by establishing an association with other quantitative and qualitative means of evaluating stockmanship. The Scorecard was used at 39 beef feedlots in Texas between March 2018 and April 2019. Eighty-four stockman were observed, and the average score received was 84.5 (SD = 14.73, range = 20 to 100). The most frequent mistakes observed were as follows: fills crowd pen/tub over half full (n = 39), slow to remove pressure (n = 29), uses unnecessary noise (n = 25), stands in front and taps rear (n = 24), and fails to regulate animal flow through a pinch point (n = 22). A strong negative association (ρ = −0.51) was found between the points deducted from the Noise and Physical Contact theme of the Scorecard and the number of animals touched with an electric prod from the BQA Feedyard Assessment. Moderate negative associations were found between the Scorecard final score and the number of animals that vocalize in the chute prior to procedures (ρ = −0.31). Those stockmen that scored above average on the Scorecard were qualitatively observed to be calm and quiet while working with the cattle (Kappa = 0.44). The qualitative disposition of cattle had little effect on the final score of stockmen using the Scorecard (Kappa = 0.17). The use of the Scorecard in a feedlot setting has demonstrated that as stockman scores decrease, there is an increase in the number of negative actions toward cattle and a negative behavioral response of the cattle themselves. Establishment of an association between a stockman’s score using the Stockman’s Scorecard and the animal-based observations from the BQA Feedyard Assessment further strengthens the validity of the Stockman’s Scorecard as a tool to measure the quality of beef cattle stockmanship. The Scorecard has application as a tool to identify specific stockmanship deficiencies in order to target stockmanship training.

Human proximity seeking in family pigs and dogs

Family dogs (Canis familiaris) seek human contact from an early age, can discriminate and prefer their caregivers over other humans. To investigate if being kept as a family animal is sufficient to induce similar early human proximity-seeking in another domestic mammal, here we directly compared such behaviours in dogs and similarly raised domestic pigs (Sus scrofa domesticus). We used a preference test to measure proximity-seeking behaviours of 4-month-old family pigs and dogs in the presence of their caregiver and either a stranger or a familiar object, in a novel environment. We found that both pigs and dogs preferred their caregivers over the familiar object but not over the stranger. However, when the caregiver and the stranger were present, only dogs showed an overall preference for human proximity, and pigs spent more time away from both humans. These results suggest that both dogs and pigs seek the proximity of their caregiver, but there is a difference in how each species generalizes their experience to other humans. Species-specific predispositions, including that dogs have a longer socialization period and that humans are more salient as a social stimulus for them, may be important for the early development of an overall preference for humans.

Manipulable Object and Human Contact: Preference and Modulation of Emotional States in Weaned Pigs

Enriching the life of farm animals is a legal obligation in intensive farming conditions in the European Union, though not worldwide. In pigs, manipulable materials are mandatory when no bedding is available. Like manipulable objects, positive human interactions might also be considered as enrichment, as they provide the animals with opportunities to interact, increase their activity and lead to positive emotional states. In this study, we investigated how weaned pigs perceived an inanimate manipulable object and a familiar human. After a similar (in length, frequency, and procedure) familiarization to both stimuli, 24 weaned pigs were tested for a potential preference for one of the stimuli and submitted to isolation/reunion tests to evaluate the emotional value of the stimuli. We hypothesized that being reunited with a stimulus would attenuate the stress of social isolation and promote a positive state, especially if the stimulus had a positive emotional value for pigs. Although our behavioral data showed no evidence that pigs spent more time close to, or in contact with, one of the stimuli during a choice test, pigs more often approached the human and were observed lying down only near the human. Using behavioral and bioacoustic data from isolation/reunion tests, we showed that a reunion with the human decreased the time spent in an attentive state and mobility of pigs to a greater extent than a reunion with the object, or isolation. Vocalizations differed between reunions with the object and the human, and were different from those during isolation. The human and object presence led to higher frequency range and more noisy grunts, but only the human led to the production of positive shorter grunts, usually associated with positive situations. In conclusion, pigs seemed to be in a more positive emotional state, or be reassured, in the presence of a familiar human compared to the object after a short period of social isolation. This confirms the potential need for positive pseudo-social interactions with a human to enrich the pigs' environment, at least in or after potentially stressful situations.

The Power of a Positive Human-Animal Relationship for Animal Welfare

Domestic animals often seek and enjoy interacting with humans. Positive human-animal relationships can elicit positive emotions and other positive welfare outcomes. Nevertheless, our understanding of the underlying processes that govern the positive perception of humans by animals is incomplete. We cover the potential mechanisms involved in the development and maintenance of positive human-animal relationships from the perspective of the animal. This encompasses habituation, associative learning, and possibly attachment or bonding based on communication and social cognition. We review the indicators from the literature to assess a positive human-animal relationship. We operationally define this positive relationship as the animal showing voluntary approach and spatial proximity (seeking) and signs of anticipation, pleasure, relaxation, or other indicators of a rewarding experience from interacting with the human. For research, we recommend accounting for the baseline human-animal relationship in the animal's everyday life, and incorporating a control treatment rather than only comparing positive to negative interaction treatments. Furthermore, animal characteristics, such as previous experience, genetics, and individual predisposition, as well as contextual characteristics related to the social and physical environment, may modulate the perception of humans by animals. The human-animal relationship is also influenced by human characteristics, such as the person's familiarity to the animal, attitudes, skills, and knowledge. We highlight implications for current practices and suggest simple solutions, such as paying attention to the animal's behavioral response to humans and providing choice and control to the animal in terms of when and how to interact with humans. Practical applications to achieve a positive perception of humans could be better utilized, such as by incorporating training principles, while keeping in mind trust and safety of both partners. Overall, there is growing evidence in the scientific literature that a positive human-animal relationship can bring intrinsic rewards to the animals and thereby benefit animal welfare. Further research is needed on the underlying processes to establish an effective positive human-animal relationship, especially in regard to the type, frequency, and length of human interaction necessary. In particular, the importance of providing animals with a sense of agency over their interactions with humans remains poorly understood.

Piglets vocally express the anticipation of pseudo-social contexts in their grunts

Emotions not only arise in reaction to an event but also while anticipating it, making this context a means of accessing the emotional value of events. Before now, anticipatory studies have rarely considered whether vocalisations carry information about emotional states. We studied both the grunts of piglets and their spatial behaviour as they anticipated two (pseudo)social events known to elicit positive emotions of different intensity: arrival of familiar conspecifics and arrival of a familiar human. Piglets spatially anticipated both pseudo-social contexts, and the spectro temporal features of grunts differed according to the emotional context. Piglets produced low-frequency grunts at a higher rate when anticipating conspecifics compared to anticipating a human. Spectral noise increased when piglets expected conspecifics, whereas the duration and frequency range increased when expecting a human. When the arrival of conspecifics was delayed, the grunt duration increased, whereas when the arrival of the human was delayed, the spectral parameters were comparable to those during isolation. This shows that vocal expressions in piglets during anticipation are specific to the expected reward. Vocal expressions-both their temporal and spectral features- are thus a good way to explore the emotional state of piglets during the anticipation of challenging events.

Effects of Long-Term Gentle Handling on Behavioral Responses, Production Performance, and Meat Quality of Pigs

Simple Summary

As an important part of modern livestock production, human–animal relationships influence the welfare of farm animals. Previous studies have shown that short-term gentle handling can reduce pigs’ anxiety, and improve production performance and possibly meat quality. However, the effectiveness of long-term gentle handling is still unknown. Therefore, this study aimed to investigate the impact of gentle handling of growing pigs over a relatively long period of time on their behavior, production performance, and meat quality after slaughter. Our results show that gentle handling increased intimacy between the handler and handled pigs, whereas long-term gentle handling had little effect on pig production performance, or on carcass and meat quality. On the other hand, long-term gentle handling had positive effects on production performance, and reduced pigs’ anxiety and increased their willingness to approach the handler. Hence, this study provides insights into the positive effects of long-term human–animal interactions on pig production.

Abstract

In order to investigate the effect of gentle handling on the behavior, performance, and meat quality of pigs from weaning to slaughter, 144 6-week-old weaned hybrid Min piglets (a native breed) were selected and divided into a handling group (HG: 9 pens × 8 pigs) and a control group (CG: 9 pens × 8 pigs). After 6 weeks of handling, we observed and then evaluated the pigs’ responses to a handler with behavioral scores. Moreover, we measured heart rate and production performance. Three pigs were randomly selected from each of the 18 pens and divided into a handling group (HG: n = 27) and a control group (CG: n = 27), and the HG pigs were given gentle handling until slaughter. Subsequently, we evaluated meat quality and the production performance of six pigs from each group. The results show that AA test (approaching–avoidance test) scores in HG pigs, the number of contacts with the handler and absence of contact with the handler, were significantly higher than in the CG pigs (p < 0.01). The occurrences of avoidance and looking at the handler were lower in the HG than in the CG group (p < 0.01); however, heart rate was not found to be significantly different between the two groups (p = 0.63). No significant difference was found in the average daily gain, average daily feed intake, and feed conversion ratio between the two groups during the two periods (p > 0.05). The b* value was determined 45 min after slaughter, and it was significantly lower in the HG than that in the CG group (p = 0.002). Furthermore, 2 h after slaughter, the L value of the HG group was significantly higher than that of the CG group (p = 0.047), but no difference was observed in carcass quality or other meat quality indicators between the two groups (p > 0.05). The results indicate that gentle handling could reduce pigs’ anxiety and increase their willingness to approach the handler, increasing the intimacy of the pigs and handlers. However, long-term gentle handling had little effect on pig performance, carcass quality, and meat quality.

Artificial Grooming during Early Life could Boost the Activity and Human Affinity of Holstein Female Calves

Simple Summary

Due to early cow–calf separation in modern farms, maternal care, such as licking and grooming, is greatly limited for newborn calves. Physically imitating the maternal licking with manual brushing, termed artificial grooming, during an early age might substitute the role of cows. The behavioral response of dairy calves with artificial grooming treatment was investigated. We found beneficial effects of artificial grooming on the activity and human–animal bonding of dairy calves. The starter ingestion might be advanced by the artificial grooming and might contribute to a less stressful weaning process. Mechanization of this process is promising in the future calf management and thus improving the welfare status of dairy calves.

Abstract

Early cow–calf separation management induced various welfare problems for dairy calves. We mimicked the maternal licking by manually brushing right after the Holstein female calves were born and during their first week of life, termed artificial grooming (AG). The behavior of these treated calves (AG, n = 17) was compared with the calves without artificial grooming (Con, n = 16) during daily behavioral observation around evening milk feeding and in the open field test (OFT) and novel human test (NHT). The number of calves ingesting starter on day six was recorded. The AG calves were observed to be more active and perform more oral behavior compared with the Con calves around evening milk feeding. In the OFT and NHT, the AG calves were again more active than the Con calves. Moreover, the AG calves tended to be less cautious and had more human interactions than the Con calves in the NHT. There tended to be a higher percentage of AG calves ingesting starter on day 6. In conclusion, artificial grooming during early life could boost the activity and the human affinity of female calves and it might advance their starter diet ingestion.

Social Behavior and Welfare in Nile Tilapia

Fish social behavior can be affected by artificial environments, particularly by factors that act upon species that show aggressive behavior to set social rank hierarchy. Although aggressive interactions are part of the natural behavior in fish, if constant and intense, such interactions can cause severe body injuries, increase energy expenditure, and lead the animals to suffer from social stress. The immediate consequence of these factors is a reduced welfare in social fish species. In this paper, we consider the factors that impact on the social behavior and welfare of Nile tilapia, an African cichlid fish widely used both in fish farms and in research; this species is frequently used as a model for physiology and behavior research. This is a polygynous species whose males interact aggressively, establishing a territorial based hierarchy, where a dominant male and several subordinate males arise. When social stability is shrunk, the negative effects of prolonged fighting emerge. In this paper, we summarized how some of the common practices in aquaculture, such as classifying individuals by matching their sizes, water renewal, stock density, and environment lighting affect Nile tilapia social aggressive interactions and, in turn, impact on its welfare. We also discuss some ways to decrease the effects of aggressive interactions in Nile tilapia, such as environment color and body tactile stimulation.

Tactile stimulation reduces aggressiveness but does not lower stress in a territorial fish

Body tactile stimulation has a positive effect upon highly social animals, such as mammals and cleaner-client coral-reef fish, by relieving stress and improving health. Conversely, some tactile contacts are naturally detrimental, such as those resulted from aggressive interactions. To study whether positive responses from tactile stimulation are generalized among vertebrates, we tested its effect on stress response and aggressive behavior in a territorial fish species, Nile tilapia. We developed an apparatus made of a row of sticks bordered by silicone bristles that was positioned in the middle of the aquarium, and through which fish had to pass to access food, thus receiving tactile stimulation. Isolated fish experienced tactile stimulation for 7 days, and  were assigned to 2 types of stressors: non-social (confinement) or social (aggressive interaction). Each of them had a corresponding control treatment without tactile stimulation. Although fish spontaneously crossed the apparatus, we did not observe a decrease in plasma cortisol levels immediately after stressor application as a response to the use of the apparatus, either for social or non-social treatment. However, tactile stimulation reduced aggressive interaction in the social treatment, showing a positive effect on a territorial fish species, and pointing to a way to improve welfare.

Coping Style Modifies General and Affective Autonomic Reactions of Domestic Pigs in Different Behavioral Contexts

Based on individual adaptive strategies (coping), animals may react differently to environmental challenges in terms of behavior and physiology according to their emotional perception. Emotional valence as well as arousal may be derived by measuring vagal and sympathetic tone of the autonomic nervous system (ANS). We investigated the situation-dependent autonomic response of 16 domestic pigs with either a reactive or a proactive coping style, previously selected according to the backtest which is accepted in piglets to assess escape behavior. At 11 weeks of age, the pigs were equipped with an implantable telemetric device, and heart rate (HR), blood pressure (BP) and their respective variabilities (HRV, BPV) were recorded for 1 h daily over a time period of 10 days and analyzed in four behavioral contexts (resting, feeding, idling, handling). Additionally, the first minute of feeding and handling was used for a short-term analysis of these parameters in 10-s intervals. Data from day 1-3 (period 1) and day 8-10 (period 2) were grouped into two separate periods. Our results revealed general differences between the coping styles during feeding, resting and handling, with proactive pigs showing higher HR compared to reactive pigs. This elevated HR was based on either lower vagal (resting) or elevated sympathetic activation (feeding, handling). The short-term analysis of the autonomic activation during feeding revealed a physiological anticipation reaction in proactive pigs in period 1, whereas reactive pigs showed this reaction only in period 2. Food intake was characterized by sympathetic arousal with concurrent vagal withdrawal, which was more pronounced in proactive pigs. In contrast, neither coping style resulted in an anticipation reaction to handling. Vagal activation increased in reactive pigs during handling, while proactive pigs showed an increase in sympathetically driven arousal in period 2. Our findings confirm significant context-related differences in the general autonomic reaction of pigs with different coping styles. Additionally, the two coping styles differ in their affective appraisal over the time course of the experiment, underlining the importance of taking individual differences into account when studying affect and emotion in humans and animals.

Promoting positive states: the effect of early human handling on play and exploratory behaviour in pigs

It is known that tactile stimulation (TS) during ontogeny modifies brain plasticity and enhances the motor and cognitive skills. Our hypothesis was that early handling including TS would increase play and exploratory behaviour in commercial pigs under standardized test conditions. Piglets from 13 litters were subjected to three handling treatments from 5 to 35 days of age: all the piglets were handled (H), none of the piglets were handled (NH) or half of the piglets in the litter were handled (50/50). At 42 days of age, the pigs' behaviour was observed in pairs in a novel pen with a 'toy' (tug rope). The main results were that more locomotor play was performed by pigs from litters where all or half of them had been handled, whereas social exploratory behaviour was more pronounced in pigs from litters where half of them had been handled. Although behaviour was affected by the interaction of treatment with sex or with weight category, we propose that the handling procedure does seem to have acted to increase locomotor skills and that handling half of the piglets in the litter may have triggered a series of socio-emotional interactions that were beneficial for the whole group.