Animals in distress can experience an attenuation of their stress response if provided companionship. This thesis studied the social support phenomenon in 72 nine-week old juvenile pigs (Sus scrofa domesticus) of the crossbreed Yorkshire/Hampshire. Pigs were placed either alone or with a familiar or an unfamiliar age-matched conspecific of the opposite sex in a stunning box. Half of the groups were exposed to an air-filled foam inside of the box and the other half was exposed to an empty box. All pigs underwent an individual behaviour assessment at eight-weeks of age for a personality evaluation. The results of this thesis indicate that pigs were startled by the foam exposure as suggested by changes in activity, escape attempts and vocalisations. Indications of social buffering were found with regards to performance of escape attempts, altered activity patterns and engagement in affiliative social behaviours. Differences were observed in the social behaviour of familiar and unfamiliar pig pairs, suggesting that familiarity between pigs should be preferred from a welfare perspective. Correlations between possible personality traits and the pigs’ behaviour in the foam box study can be understood within the coping style framework. The results suggest that pigs show variation in their need for social support and that personality could have been a bias in interpreting the pigs’ behavioural response to the foam stunning situation. This thesis provide support that the welfare of pigs during foam stunning may be improved if pigs are stunned in groups of familiar individuals.

Stress cannot be fully avoided in an animal´s life, and the way that animals handle stress can be crucial for their health. Coping styles in animals are describing consistent sets of behaviour and physiological stress responses. Two forms of coping are typically described; a more proactive type that is more bold, active, and aggressive, and, in contrast, a less active, more shy reactive type. Coping styles can be used to learn how animals react to stress, and thus improve our handling of stress in captive animals. To investigate the existence of the reactive-proactive coping styles in the red junglefowl (Gallus gallus), both male and female red junglefowl were exposed to behavioural assays measuring boldness, activity, exploration, and aggression. These behavioural measures were compared to blood plasma concentrations of the stress hormone corticosterone, hence exploring the link between behaviour and physiological response to stress. I show positive correlations between boldness, activity, and exploration measured in a novel arena test, and boldness and activity measured in a novel object test. This somewhat confirms the inter-related behavioural aspect of reactive-proactive coping styles. Further, some of these behaviours correlated with post-stress concentrations of corticosterone, which somewhat links behaviour to the physiological aspect of coping styles. This study tentatively supports the reactive-proactive coping styles by showing a link between behaviours and the physiological stress response in the red junglefowl, with some similarities to what have been observed in other species across taxa.

Dogs have lived with us for thousands of years, so we have learned to understand one another. Dogs have been shown to synchronize their behavior with humans. Behavioral synchronization is characterizes by doing the same thing at the same time and in the same place as someone else. This synchronization is often dependent on the relationship and the emotional state of the individuals. The main aim in this study was to develop a method to test behavioral synchronization and also to investigate how this, but also other behaviors, are effect by preceding human-dog interactions. Privately owned dogs (N=21) were tested with three different treatments (play, pet or ignore). The test procedure consisted of the owner walking or standing still in a predefined pattern, while their dog was freely roaming. This study showed that dogs adapted their movement pattern to their owners. This was similar to previous studies showing that the method developed can be used to test behavioral synchronization between owner and dog. Dogs explored the test arena less after play interaction and they also tended to seek more eye contact with their owners, but the interactions did not affect how much time spent in human proximity, how much they followed them or on dogs movement pattern.

The evolutionary origins of human handedness are still unknown. The study of lateralized behaviour in our closest relatives, the nonhuman primates, is useful to clarify how this trait appeared and evolved in our species. In the present study, lateralized behaviour was assessed in a population of 32 free-ranging Mexican mantled howler monkeys (Alouatta palliata mexicana) for thirteen spontaneous motor patterns, at individual and group levels, as well as the effect that age, sex and posture have on its strength and direction. The studied population of howler monkeys displayed only few significant lateral biases at the individual level with single motor patterns (Binomial tests, p≤0.05). No biases towards the use of a particular limb or side of the body were found at a population level. Therefore, even though some individuals showed significant limb/side preference with single motor patterns, no signs of task specialization, side specialization, or true handedness were found. Similarly, no effects of sex, age or posture were found on the direction or strength of lateralized behaviour. The general absence of limb/side preferences found in this population may be due to the constraints imposed by the arboreal life and/or the type of diet. Possible causal agents of the few significant individual biases found here may be the presence of handicaps and/or experience. Further research is needed in order to assess whether the lack of human-like handedness reported in this study is only specific to the studied population, a general phenomenon of the genus Alouatta or perhaps of all the Platyrrhini.

Cognitive processes include biases, such as cognitive judgment bias. Cognitive judgment bias influences how the surrounding is interpreted, and this can differ between individuals. However, thus far no formal framework exists to understand how cognitive judgment bias works. Here I investigated how environmental factors and personality influence cognitive judgment bias in Gallus gallus chicks. First I investigated how two environmental factors affected the cognitive judgment bias of laying hen chicks. Chicks were exposed to stress and/or environmental enrichment, and tested in a cognitive judgment bias test before and after collective unpredictable stressors were presented. The results showed that chicks living in enriched environments were faster to reach all cues after the collective stressors than chicks living in non-enriched environments. Individual differences are often observed in animals, even when raised under identical conditions; therefore I also investigated if variation in personality influence cognitive judgment bias. Red junglefowl chicks were thereby raised in equal environments and exposed to personality assays in addition to a cognitive judgment bias test. I demonstrated that less nervous chicks were more optimistic towards ambiguous and negative cues than more nervous chicks. Also previous studies have found indications of connections between cognitive bias and environment or personality. I conclude that environmental enrichment can buffer the influence of stress on cognitive judgment bias and that personality has a small influence on interpretations of stimuli. In the future, experiments in this field should focus on exploring more aspects on how cognitive biases occurs to improve our understanding of cognitive processes.

Cognitive bias can be used when determining emotional states in animals by assessing the animal’s perception of an ambiguous stimulus. In the concept of animal welfare, both physical health as well as mental health of animals are involved. Therefore, cognitive bias can be a valuable tool in order to measure the mental health of an animal. The aim of this paper is to summarize and discuss how cognitive bias tests have been used to assess emotional states in dogs. Cognitive bias tests in dogs have been used to evaluate the emotional state of a dog with behavioural problems. It has also been shown to be useful when studying the effect of enrichment in the form of natural behaviour, such as being allowed to use its olfactory sense to a greater extent. Additionally, the connection between personality and cognitive bias is discussed. Hence, assessing the emotional state of dogs can be valuable in a welfare perspective.

Animal behavior has become a frequently used tool in modern ecology and ecotoxicology, where laboratory behavioral traits are recognized as sensitive endpoints for assessing natural behavior or non-lethal effects of pollutants on animals. Within these research fields, behavioral traits measured in laboratory environments have been used to formulate predictions of ecological consequences that accompany specific behavior. However, the predictive power of behavioral traits measured in simplified laboratory environments for complex natural aquatic ecosystems has been questioned. In this study, I have examined to what extent behavioral changes, noted in laboratory settings in response to chemical stressors (an anxiolytic drug) or visual cues of black and white bottom substrates, are also expressed in the wild. In my first experiment, I scrutinized whether reduced social behavior previously shown to occur in the lab for European perch (Perca fluvatilis) in response to oxazepam also occurs within a natural lake subjected to oxazepam. The in situ behavior was measured using high temporal resolution (3 sec) acoustic telemetry. In my second experiment, I assessed if the Atlantic salmon’s (Salmo salar) preference for black bottom substrates (scototaxis) in laboratory assays could be utilized for guiding migrating Atlantic salmon in situ. I show that: i) Oxazepam does not affect the social (association) behavior or the social network structure of perch in natural settings, in contrast to laboratory-based predictions; ii) Atlantic salmon show a preference for black bottom substrates both in laboratory- and natural environments. My study with oxazepam underlines that abiotic environmental factors and collective decision making in-situ, can override the anti-social behavioral effects of oxazepam on perch in a natural Lake. However, there seems to be potential in using laboratory behavioral assays to predict behavior in the wild, given that there is a tendency for migrating salmon to follow black bottom substrates both in laboratory environments and in streams.

Sammanfattning Användningen av korttidsreglering av vattenkraftverk kommer troligen öka då det är kostnadseffektivt och efterfrågan av förnybar energi är hög. Jag undersökte effekten av habitatkomplexitet och flödesändringar på simaktiviteten hos harr (Thymallus thymallus) i experimentella vattenrännor. Två olika habitat användes, ett beståendes av bara en grusbotten och en med större stenar placerade på grusbotten. I experimentet användes en behandling där flödet var stabilt och en där flödet varierade. Det fanns en signifikant interaktionseffekt mellan en ändring i flödet och habitat, som visade att simaktivitet ökade i samband med flödesändring, men endast i habitatet utan större stenar. I jämförelse av två konstanta flöden visade också studien att simaktivitet minskade med högre vattenhastighet. Effekter som dessa bör uppmärksammas för att bättre förstå påverkan korttidsreglering kan ha på fiskar i rinnande vatten. / Abstract The use of hydropeaking by hydropower plants will probably increase due to it being cost-effective and the demand for renewable energy being high. I examined the effect of habitat complexity and changes in flow on the swimming behaviour of graylings (Thymallus thymallus) in experimental flumes. Two types of habitats were used, one consisting only of a bed of gravel and the other with large stones added to the gravel bottom. In the experiment, one treatment with stable flow and one with variable flow were used. There was a significant interaction effect between change of the flow and type of habitat, indicating that swimming activity increased in changing flow, but only in the habitat without large stones. When comparing two constant flows the study also showed that swimming activity decreased with increased water velocity. Effects such as these should be considered when trying to understand how hydropeaking affects riverine fishes.

Unsocialized stray dogs live unrestrained in urban areas, having limited to no direct contact with humans. Aggressive behaviour towards humans leads to their apprehension to shelters, where they tend to stay permanently. This study aimed to determine if unsocialized stray dogs could be rehabilitated and develop the social skills needed for adoption. Six unsocialized stray dogs (Group Stray) and 12 socialized dogs (C1: Control Group 1, n=6; C2: Control Group 2, n=6) housed in a shelter were selected. Stray and C2 dogs went through two training phases: social rehabilitation towards humans and leash training. Sociability towards humans and behaviour on a leash were tested in all groups following Valsecchi et al. (2011). Sociability Tests (ST) and Leash Tests (LT) were conducted before any intervention (ST1), after sociability training (ST2, LT1) and after leash training (ST3, LT2). Training sessions and tests were video recorded and posteriorly analysed by four observers. Results showed that for Stray, but not for C1 and C2, there was a significant increase in sociability from ST1 to ST3. Moreover, for Stray Group there was a significant decrease in the frequency of fear-related behaviours between ST1 and ST3. For leash behaviour, no significant changes were found from LT1 to LT2 for neither group. However, there was considerable individual variation, as not all strays overcame their extreme fear towards humans. These findings suggest that dog­–human interactions can be improved through training for dogs who do not show extreme fear and/or aggression towards humans.

For about 14 000 years ago the domestication of the wolf, Canis lupus, began. This initiated the extensive work of breeding that resulted in man´s best friend, the dog. Its Latin name, Canis lupus familiaris, clearly shows how close they stand us people today. The Swedish Kennel Club has 343 registered breeds which are very different from each other in terms of the exterior, but also behaviourally. The behavioural differences in adult dogs of different breeds are commonly known. Something that is still in dispute is when these differences begin to manifest in the dog´s life. In this study two interview investigations were conducted with the aim to see whether distinct behavioural differences between breeds could be identified in the puppy stage. The breeds that were included in the study were American Staffordshire terrier, Border collie and Whippet. Two questionnaires were designed. One was sent to breeders because they were considered to have the most experience of the breeds in question. The other questionnaire was sent to veterinarians to get a more objective picture of the puppies’ behaviour. The results from the breeders showed that there was a statistically significant difference between the American Staffordshire terrier and Whippet puppies in their curiosity and the way they behaved socially. The outcome of the study is very interesting because it could mean that the breeding not only affects the behaviours of the adult dogs, but also the behavioural patterns of puppies. The results from the veterinarians showed that there was no difference between the breeds. The difference in results between the two groups could be due to the fact that different questions were asked, they have different preferences for the breeds, meet them in different environments, for different lengths of time or other sources of error. Further studies in this area are needed to investigate when the differences, which give dogs the title of the most varied species ethologically speaking, begin to appear.