Attenuation of fear through social transmission in groups of same and differently aged horses

From whom do animals learn? A meta-analysis on model-based social learning

Social learning via the observation of or interaction with other individuals can allow animals to obtain information about the local environment. Once social information is obtained, animals may or may not act on and use this information. Animals may learn from others selectively based on particular characteristics (e.g., familiarity, age, dominance) of the information provider, which is thought to maximize the benefits of social learning. Biases to copy certain individuals over others plays an important role in how information is transmitted and used among individuals, and can influence the emergence of group-level behaviors (i.e., traditions). Two underlying factors can affect from whom animals learn: the population social dynamics - with whom you associate (e.g., familiar), and status of the demonstrator (e.g., dominant). We systematically surveyed the literature and conducted a meta-analysis to test whether demonstrator characteristics consistently influence social learning, and if social dynamics strategies differ from status strategies in their influence on social learning. We extracted effect sizes from papers that used an observer-demonstrator paradigm to test if the characteristics of the individual providing social information (i.e., the demonstrator) influence social information use by observers. We obtained 139 effect sizes on 33 species from 54 experiments. First, we found an effect of experimental design on the influence of demonstrator characteristics on social learning: between-subject designs had stronger effects compared to within-subject designs. Second, we found that demonstrator characteristics do indeed influence social learning. Characteristics based on social dynamics and characteristics based on status had a significant effect on social learning, especially when copying familiar and kin demonstrators. These results highlight the role that demonstrator characteristics play on social learning, which can have implications for the formation and establishment of behavioural traditions in animals.

A calm companion lowers fear in groups of dairy cows

Dairy cows are generally calm and compliant, but some management procedures can make cows fearful or stressed. Not only are fearful cattle a threat to human safety, but fear is also detrimental to animal welfare and productivity. This study aimed to test whether fear in small groups of dairy cattle could be attenuated by the presence of a calm and experienced companion. Twenty-seven dairy cows from a Swedish agricultural school participated in the study. The study included a standardized fear-eliciting stimulus, which was 3 sudden, repetitive openings of a red and white umbrella. Demonstrator cows (n = 9) were selected based on age to ensure that all demonstrators were older than the naïve test cows (n = 18). Of these 9 demonstrator cows, 6 were selected as untrained (i.e., habituated to the presence of the test person) and 3 were selected as trained demonstrators (i.e., additionally habituated to the fear-eliciting stimulus). The remaining 18 test cows comprised 6 test-cow groups of 3 cows each, which were their own controls, resulting in a crossover design; 3 groups were tested with a trained demonstrator first and then with an untrained demonstrator, and vice versa for the other 3 groups, resulting in a total of 12 trials (4 sub-treatments). Response variables were heart rate increase from baseline, behavioral reaction indicative of fear, and latency to resume feeding after exposure to the fear-eliciting stimulus. The study found a calming effect of a trained demonstrator on test cows' heart rate but not on latency to resume feeding or behavioral reaction. Post hoc analyses revealed a carryover effect on latency, indicating that test cows who were accompanied by an untrained demonstrator first had longer latencies than cows in all other sub-treatments. Adding a calm, experienced cow to groups of dairy cattle may mitigate fear and thereby improve welfare and safety.

The Neurobiology of Behavior and Its Applicability for Animal Welfare: A Review

Simple Summary

Animal welfare is the result of physical and psychological well-being and is expected to occur if animals are free: (1) from hunger, thirst and malnutrition, (2) from discomfort, (3) from pain, (4) to express normal behavior, and (5) from fear and distress. Nevertheless, well-being is not a constant state but rather the result of certain brain dynamics underlying innate motivated behaviors and learned responses. Thus, by understanding the foundations of the neurobiology of behavior we fathom how emotions and well-being occur in the brain. Herein, we discuss the potential applicability of this approach for animal welfare. First, we provide a general view of the basic responses coordinated by the central nervous system from the processing of internal and external stimuli. Then, we discuss how those stimuli mediate activity in seven neurobiological systems that evoke innate emotional and behavioral responses that directly influence well-being and biological fitness. Finally, we discuss the basic mechanisms of learning and how it affects motivated responses and welfare.

Abstract

Understanding the foundations of the neurobiology of behavior and well-being can help us better achieve animal welfare. Behavior is the expression of several physiological, endocrine, motor and emotional responses that are coordinated by the central nervous system from the processing of internal and external stimuli. In mammals, seven basic emotional systems have been described that when activated by the right stimuli evoke positive or negative innate responses that evolved to facilitate biological fitness. This review describes the process of how those neurobiological systems can directly influence animal welfare. We also describe examples of the interaction between primary (innate) and secondary (learned) processes that influence behavior.

Still beyond a chance: Distribution of faults in elite show-jumping horses

This study aimed to identify factors that can influence show-jumping performance during top level competitions in the Western European League (2017/2018, CSI5*). The performance data of 144 riders and 222 horses were obtained from video records (FEI TV/ website). Riders with horses achieved a total of 9114 jumping-efforts over 320 obstacles including oxers (n = 142), oxers with water (n = 15), triple bars (n = 6), verticals (n = 136), verticals with water (n = 14) and walls (n = 7). Obstacles in the first round (FR) or in jump off (JO) were standing either as single (n = 6290) or as a combination of two or three fences in a row (n = 2824). The overall fault rate (dropping the pole or refusal/run-out to jump) was 7.85%. The probability of a fault increased with the rank of the fence in the course of FR (F _{(1, 7649)} = 5.29, P < 0.0001, GzLMM; PROC GLIMMIX, SAS). The highest probability of a fault (F _{(5, 7649)} = 2.51, P < 0.03) in FR was found on the vertical obstacle with water (0.125 ± 0.021, LSMEAN ± standard error) while the lowest was on the triple bar (0.037 ± 0.015) and wall (0.048 ± 0.020). Riders who completed more starts in previous competitions achieved a lower fault rate (F _{(1, 7649)} = 6.17, P < 0.02) in FR as well as in JO (F _{(1, 931)} = 7.05, P < 0.01). The probability of faults in JO decreased with a higher speed (F _{(1, 931)} = 6.66, P < 0.01) but there was no significant correlation between the speed in JO and FR in individual horses (r = 0.26, P < 0.01). More faults were found on the fences within combinations in both rounds (FR, JO). The highest probability of faults was found on the first fence (FR 0.095 ± 0.016; JO 0.043 ± 0.008) or second fence (JO 0.055 ± 0.020) of the double combination compared to the least probability of faults on single obstacles (FR 0.057 ± 0.007, F _{(5, 7649)} = 5.29, P < 0.0001; JO 0.100 ± 0.027, F _{(1, 931)} = 3.39, P < 0.04). Other tested factors did not affect show-jumping performance. Some faults are still more likely and not random in a show-jumping course, therefore, the appropriate training focus can improve performance and safety in competitions.

Psychological and Physiological Stress in Hens With Bone Damage

Abnormalities in bone development in humans and non-humans can lead to impaired physical and psychological health; however, evidence is lacking regarding the role of individual psychosocial factors in the development of poor bone conditions. Addressing this lack of knowledge, we used low-productive laying hens (n = 93) and assessed behavioral responses to an open-field test [at 17, 18, 29, 33 weeks of age (wa)], an aerial predator test (at 39 wa), and a social reinstatement test (at 42 wa). Bone condition was assessed using a palpation technique on five occasions (at 16, 29, 33, 45, 58 wa), with half of the hens experiencing damage (deviations, fractures, or both) at 29 wa and all hens by 58 wa. Corticosterone (CORT) concentration in feathers (at 16, 33, 58 wa) and body weight (at 23, 47, 58 wa) were also investigated. We hypothesized that lighter birds (at 23 wa) with higher CORT (at 16 wa) and open field-induced fear collected before the onset of lay (at 17 and 18 wa) are associated with a worse bone condition when in lay. We also hypothesized that those birds with more damage at the peak of laying (at 29 wa) would be lighter at 47 and 58 wa and more fearful by showing higher open field-induced (at 29 and 33 wa) and predator-induced fear responses, however, acting less socially toward conspecifics. These hens were also expected to have higher CORT (at 33 and 58 wa). Our results show no association between open-field fear level and fear behavior, CORT concentration, or body weight on the one hand (all measured before starting to lay) and bone damage at 29 wa on the other. When in lay, bone damage was associated with more pecking and less crossing zones when faced with an open-field situation at 29 wa and improved sociality at 42 wa. This study provides the first evidence of a relationship of bone health with fear, sociality, and stress response. When in poor bone condition, our hens had enhanced psychological stress measured by fear behavior reactivity but not physiological stress measured as feather CORT concentration.

Sensory Abilities of Horses and Their Importance for Equitation Science

Vision, hearing, olfaction, taste, and touch comprise the sensory modalities of most vertebrates. With these senses, the animal receives information about its environment. How this information is organized, interpreted, and experienced is known as perception. The study of the sensory abilities of animals and their implications for behavior is central not only to ethology but also to animal welfare. Sensory ability, perception, and behavior are closely linked. Horses and humans share the five most common sensory modalities, however, their ranges and capacities differ, so that horses are unlikely to perceive their surroundings in a similar manner to humans. Understanding equine perceptual abilities and their differences is important when horses and human interact, as these abilities are pivotal for the response of the horse to any changes in its surroundings. This review aims to provide an overview of the current knowledge on the sensory abilities of horses. The information is discussed within an evolutionary context and also includes a practical perspective, outlining potential ways to mitigate risks of injuries and enhance positive horse-human interactions. The equine sensory apparatus includes panoramic visual capacities with acuities similar to those of red-green color-blind humans as well as aural abilities that, in some respects exceed human hearing and a highly developed sense of smell, all of which influence how horses react in various situations. Equine sensitivity to touch has been studied surprisingly sparingly despite tactile stimulation being the major interface of horse training. We discuss the potential use of sensory enrichment/positive sensory stimulation to improve the welfare of horses in various situations e.g. using odors, touch or sound to enrich the environment or to appease horses. In addition, equine perception is affected by factors such as breed, individuality, age, and in some cases even color, emphasizing that different horses may need different types of management. Understanding the sensory abilities of horses is central to the emerging discipline of equitation science, which comprises the gamut of horse-human interactions. Therefore, sensory abilities continue to warrant scientific focus, with more research to enable us to understand different horses and their various needs.

Horses feel emotions when they watch positive and negative horse-human interactions in a video and transpose what they saw to real life

Animals can indirectly gather meaningful information about other individuals by eavesdropping on their third-party interactions. In particular, eavesdropping can be used to indirectly attribute a negative or positive valence to an individual and to adjust one's future behavior towards that individual. Few studies have focused on this ability in nonhuman animals, especially in nonprimate species. Here, we investigated this ability for the first time in domestic horses (Equus caballus) by projecting videos of positive and negative interactions between an unknown human experimenter (a "positive" experimenter or a "negative" experimenter) and an actor horse. The horses reacted emotionally while watching the videos, expressing behavioral (facial expressions and contact-seeking behavior) and physiological (heart rate) cues of positive emotions while watching the positive video and of negative emotions while watching the negative video. This result shows that the horses perceived the content of the videos and suggests an emotional contagion between the actor horse and the subjects. After the videos were projected, the horses took a choice test, facing the positive and negative experimenters in real life. The horses successfully used the interactions seen in the videos to discriminate between the experimenters. They touched the negative experimenter significantly more, which seems counterintuitive but can be interpreted as an appeasement attempt, based on the existing literature. This result suggests that horses can indirectly attribute a valence to a human experimenter by eavesdropping on a previous third-party interaction with a conspecific.