This literature study is about rehoming of dogs, the focus is on investigating the reason why dog get rehomed, what behavioral problems that can occur when the dog is rehomed and how to work with these problems. The study concluded that the main reasons for a dog to be rehomed are behavioral problems in the dog, health problems concerning the owners, changed living conditions and lack of time. More reasons can also contribute, and these are also discussed. Additional behavioral problems that can occur when the dog is left in a shelter include separation anxiety and stress-related behavioral problems. This study describes the stress reaction and how the stress reaction looks and work and how the stress hormone cortisol can be used measuring stress levels in the short and long term.  For the last part of the study, the study concluded how a person can work with the dog´s behavioural problems. According to research, positive reinforcement is the best method to use when training dogs. This type of trainings method strengthens the relationship between the dog and the owner and thus reduces the risk of a dog being rehomed. The study also concluded that training methods that use aversive methods can make the dog stressed, make the dog feel anxious and lead to that the dog start expressing aggressive behaviour.

During the course of time, artificial selection has given rise to a great diversity among today's dogs. Humans and dogs have evolved side by side and dogs have come to understand human body language relatively well. This study investigates whether selection pressure and domestication could reveal differences in dogs’ skill to interpret human directional cues, such as distal pointing. In this study, 46 pet dogs were tested from 27 breeds and 6 crossbreeds for performance in the two-way object choice task. Breeds that are selected to work with eye contact of humans were compared with breeds that are selected to work more independently. Dogs of different skull shape were also compared, as well as age, sex and previous training on similar tasks. No significant differences in performance were found between dogs of various age, sex or skull shape. There was a tendency for significant difference in performance if the dog had been previously trained on similar tasks. When dogs that made 100% one-sided choices were excluded, a tendency appeared for there to be a difference between the cooperative worker breeds compared to the other breeds for the time it took for dogs to make a choice. There is a correlation between the number of correct choices made and the latency for the dogs from being release to making a choice (choice latency). All groups of dogs, regardless of my categorization, performed above chance level, showing that dogs have a general ability to follow, and understand, human distal pointing.

The dear enemy effect is a widespread behavioral phenomenon that promotes selective pacifism in order to minimize costs of territorial defense. The dear enemy hypothesis predicts heightened aggression towards unfamiliar conspecifics compared to familiar neighbors where territorial boundaries are established. The purpose of this study was to test the dear enemy hypothesis in Neolamprologus multifasciatus, a social cichlid fish endemic to the shell beds of Lake Tanganyika. They establish breeding groups that control distinct territories, each governed by a dominant male. Territories can be very densely spaced, and conspecific border intrusions generally trigger aggressive responses from the focal group. The dominant males are responsible for the majority of territory defense. In this field experiment, 27 breeding groups were each given two treatments, each consisting of artificial introduction of an out-of-group dominant male. One male originated from an immediately neighboring group, the other from a distant group.  A downward-facing camera recorded group members’ aggressivity exhibited towards the experimentally presented male. The behavior was manually scored according to a behavior ethogram and analyzed with either linear mixed effects models or generalized linear mixed effects models. No clear dear enemy effect was detected within Neolamprologus multifasciatus. Several reasons are proposed for this result. Firstly, a contingent “ceiling effect” in terms of aggressive behavior imaginably deterred efforts of dear enemy detection. Conversely, perhaps negligible necessity of stranger-neighbor recognition within Neolamprologus multifasciatus has resulted in discriminatory behavior being absent. In conclusion, no dear enemy effect was detected and future research will address possible alternative explanations.

Autism is a complex disorder with possible genetic, epigenetic and environmental components. As the etiology remains uncertain and an increase in incidence is suspected, the involvement of possible environmental risk factors has gained increasing attention. With this thesis, I aim to provide tools for assessing such risk factors. Firstly, I aim to construct a questionnaire for the analysis of an environmental component in the etiology of autism. Secondly, I aim to assess the importance of prenatal exposure to metals in certain diseases and thirdly I aim to construct a methodology enabling the analysis of the mitochondrial epigenome, which is especially interesting in relation to autism as mitochondrial diseases occur more frequently in an autistic population than in the general population. For the creation of the questionnaire the scientific literature was reviewed. The resulting questionnaire contains general, prenatal, neonatal and paternal risk factors. The metal analysis was conducted on the cord blood of patients who later developed autism, antinuclear antibodies positive rheumatoid arthritis or diabetes, which were then compared to healthy control subjects. My findings propose a link between elevated levels of cord blood cadmium or aluminum and rheumatic arthritis. In addition, elevated aluminum levels might be associated with autism. In regards to the analysis of the mitochondrial epigenome, to my knowledge, no standard protocol exists with frozen human whole blood as a source. In this thesis, I succeeded in creating the basis for such a protocol, however still needing several small modifications for an increased overall yield.

Worldwide, pharmaceutical compounds continue to increase in our aquatic environment. The predominant route into nature is through wastewater treatment plants since the elimination of residual pharmaceuticals is still not mainstream in WWTPs. Fluoxetine is an antidepressant which is commonly prescribed to treat human depression. Wastewater residual fluoxetine is typically found in waters around the world, and can thus affect exposed organisms, such as fish and invertebrates. However, how fluoxetine may affect mating behaviour in exposed organisms remains poorly understood, and particularly so in invertebrates. This is hampering our understanding of the consequences of our medicine leaking into nature because mating behaviour often affects fitness, and invertebrates are key organisms in food chains. Therefore, I here experimentally investigated long-term effects of environmental relevant concentration of fluoxetine (20 ng L-1) on mating behaviours of male and female freshwater isopod Asellus aquaticus. I demonstrate that fluoxetine reduced male mating attempts with receptive females. Further, there was a tendency for fluoxetine exposure to increase latency to form pre-copula. There was no effect of fluoxetine exposure on male latency to encounter females or female responses toward males. These results indicate that fluoxetine also can affect isopods by reducing mating behaviour. In the long-term, if reproduction is delayed or reduced, it may cause a reduction in populations and thus, alter the whole ecosystem.

Semiochemicals are chemicals used to communicate. Animals tend to use these e.g. to locate food sources or to find a suitable mate. In this study, the sex pheromone of the Indian meal moth, Plodia interpunctella, was analysed. Since this is an economically important species, it is mass-reared in labs and science centers worldwide for experimental purposes. A culture of these moths was brought into the lab at Lund University for studies and has after that served as a model species demonstrating up-wind pheromone-mediated male flight in different courses held by the university. As years went by, the culture got less successful in up-wind flights, most probably because of inbreeding and bottleneck effects, and therefore, a new culture was taken in. This study focuses on using various experiments to see if there was a behavioral and/or physiological difference between the two cultures. Results show a significant difference in behavioral traits (frequency of calling behavior in females and in male up-wind flights) but not in physiological traits (female pheromone production or male antennal response). This study discusses some effects of mass-reared lab cultures.

Play is a self-motivated seemingly non-functional behavior mainly observed in young animals. Moreover, play behaviors can be divided into three categories; social play, object play and locomotor play. The type of activity the category contains varies, as play behaviors vary between species. Play behavior is seen as an indicator of positive emotions in animals, therefore play could be an indicator of welfare. However, the relationship between play and welfare requires further studies. In this study, information was compiled from various articles about play and its relation to welfare. Above all, the study focuses on welfare and play in chickens, as studies on chickens are most lacking. Play provides several benefits regarding motor training, social cohesion and cognitive training. Livestock such as calves, piglets and lambs have all been observed playing. No play has been confirmed in chickens which is mainly due to lack of research. However, play has been observed in other bird species, including birds within the order Galliformes. Amount and type of play varies depending on the environment, which suggests that animal welfare has a great significance for play. If no play occurs, one could conclude that welfare needs to be improved. Lack of play observed in chickens could be due to poor welfare or lack of research. After all, presence of play in other bird species increases the probability that chickens also play. Results indicate that play could be used as an indicator for welfare.

Lateralized behaviour is the most conspicuous manifestation of hemispheric specialization of the brain and has been reported in a variety of taxa. Only a few studies have so far assessed lateralized behaviours in horses. Therefore, I observed ten domestic horses for 16 weeks for an array of spontaneously occurring motor behaviours as well as stimulus-induced behavioural responses to determine if they display side preferences at the individual or population level and to assess possible correlations between lateralized behaviours. Significant side preferences were found for certain behaviours at the individual level, ranging from standing and flexing, to auditory stimuli, and olfactory stimuli. All horses showed task-dependent changes in their side preferences and no significant side preferences were found at the population level for any behaviours. Similarly, no significant correlations were found between behaviours. Taken together, the results of the present study suggest that horses, like all other species studied so far except humans and some great apes, only display lateralized behaviour at the individual, but not at the population level.

The purpose of this paper is to analyze how consumer behavior related to food changed during the pandemic in Sweden. At the beginning of 2020 a global pandemic named Covid-19 hit all the countries, Sweden being one of them.  The pandemic has forced everyone to change their usual lifestyle in order to be safe from the virus. The consumers' food choices have been changed during the pandemic, this topic would be interesting to be researched by the authors. Since the pandemic has urged worldwide, most of the countries have been affected because of it. The researchers have conducted a  questionnaire in order to be able to analyze the situation in Sweden from the consumers point of view. The findings indicate changes in consumer behavior and buying behavior that are tied with the pandemic times in the context of health. Some changes have been observed in product buying for food consumption as many people bought healthier products.

Filial imprinting is a type of early developmental learning in which certain species buildstrong and mostly irreversible connections to objects or individuals. These connections couldbe shaped by the contribution of several stimuli including the fragments of auditory and visual components. This study aims to describe the duration of the imprinting process as well asestimate long-term behavioural changes in chicks. In this experiment, a total of 78 chicks were used out of which 39 were exposed to imprinting stimuli and the rest served as control.We applied three different tests and replicated them after the imprinting procedure. These tests are Imprinting Preference Test, Social Preference Test and Social isolation Test. Imprinted chicks had a constantly shorter latency to approach the imprinting stimuli for boththose two experiments with or without novel objects, whereas no preferences spent time inimprinting stimuli. However, introducing a novel object affected imprinting preferences more in terms of spending a longer time around the hen zone. During social isolation, the control group showed a relatively higher rate of distress calls even though our results don’t bear on the significant effect of filial imprinting on changes in distress calling. Overall, this study suggests the presence of long-lasting filial imprinting that is more triggered by external situations.