<p>Syftet med denna studie var att undersöka om det fanns olika personlighetstyper hos mjölkkor av raserna SRB och SLB och om dessa personlighetstyper skilde sig mellan ras, ålder och vilken sida djuren stått på i lösdriften. Korna observerades i tre olika testmiljöer för att se huruvida konsistenta de var i deras beteenden: ostörda i lösdriften, vid mjölkning och med ett främmande objekt i lösdriften. Beteenden som studerades var normala beteenden, sociala beteenden, tramp och sparkningar vid mjölkning och interaktioner med det främmande objektet. Tolv beteendevariabler användes i en PCA (principal component analysis) och visade två komponenter som tillsammans kunde förklara 51,2 % av den totala variansen. Den första komponenten speglade aggression och extraversion, som ingår i medgörlighet och extraversion i den mänskliga femfaktorsmodellen. Den andra komponenten speglade ett mer introvert beteende och rädsla, som går under extraversion och neuroticism i samma modell. Oberoende T-test visade inga signifikanta skillnader mellan någon av komponenterna och ras eller sida i lösdriften p>0,05, däremot en tendens till skillnad mellan den första komponenten och ålder, där den äldre gruppen individer visade tydligare personlighetsdrag p<0.1. Tidigare studier har visat att personlighetsdimensioner som medgörlighet, neuroticism och extraversion ofta förekommer bland flera arter. Då olika personligheter hanterar stressfulla situationer på olika sätt, är detta ämne av stor vikt när det gäller förbättrandet av djurens välfärd.</p> / <p>The purpose of this study was to investigate if different personality dimensions existed in dairy cows of two breeds (SRB and Holstein) and if these personality dimensions differed between breed, age and how the animals were placed in the loose housing system. To investigate behavioural consistency, the cows were observed in three different situations: uninterrupted in their home pen, during milking and with a novel object in their home pen. Normal and social behaviour was observed as well as stepping and kicking during milking and interactions with the novel object. Twelve behavioural variables were used in a principal component analysis, which showed two components that together explained 51,2 % of the total variance. The first component reflected aggression and extraversion, which are included in agreeableness and extraversion in the human five-factor model. The second component reflected fear and introversion, which are included in neuroticism and extraversion in the same model. Independent-samples T test showed no significant differences between any of the components and breed or placement in the loose housing system p>0,05, however there was a tendency between the first component and age, where the older group showed a more defined personality p<0,1. Other studies have showed that personality dimensions such as agreeableness, neuroticism and extraversion often exist in several species. Different personalities cope with stressful situations in different ways, making this topic relevant to the improvement of animal welfare.</p>

Syftet med denna studie var att undersöka om det fanns olika personlighetstyper hos mjölkkor av raserna SRB och SLB och om dessa personlighetstyper skilde sig mellan ras, ålder och vilken sida djuren stått på i lösdriften. Korna observerades i tre olika testmiljöer för att se huruvida konsistenta de var i deras beteenden: ostörda i lösdriften, vid mjölkning och med ett främmande objekt i lösdriften. Beteenden som studerades var normala beteenden, sociala beteenden, tramp och sparkningar vid mjölkning och interaktioner med det främmande objektet. Tolv beteendevariabler användes i en PCA (principal component analysis) och visade två komponenter som tillsammans kunde förklara 51,2 % av den totala variansen. Den första komponenten speglade aggression och extraversion, som ingår i medgörlighet och extraversion i den mänskliga femfaktorsmodellen. Den andra komponenten speglade ett mer introvert beteende och rädsla, som går under extraversion och neuroticism i samma modell. Oberoende T-test visade inga signifikanta skillnader mellan någon av komponenterna och ras eller sida i lösdriften p&gt;0,05, däremot en tendens till skillnad mellan den första komponenten och ålder, där den äldre gruppen individer visade tydligare personlighetsdrag p&lt;0.1. Tidigare studier har visat att personlighetsdimensioner som medgörlighet, neuroticism och extraversion ofta förekommer bland flera arter. Då olika personligheter hanterar stressfulla situationer på olika sätt, är detta ämne av stor vikt när det gäller förbättrandet av djurens välfärd. / The purpose of this study was to investigate if different personality dimensions existed in dairy cows of two breeds (SRB and Holstein) and if these personality dimensions differed between breed, age and how the animals were placed in the loose housing system. To investigate behavioural consistency, the cows were observed in three different situations: uninterrupted in their home pen, during milking and with a novel object in their home pen. Normal and social behaviour was observed as well as stepping and kicking during milking and interactions with the novel object. Twelve behavioural variables were used in a principal component analysis, which showed two components that together explained 51,2 % of the total variance. The first component reflected aggression and extraversion, which are included in agreeableness and extraversion in the human five-factor model. The second component reflected fear and introversion, which are included in neuroticism and extraversion in the same model. Independent-samples T test showed no significant differences between any of the components and breed or placement in the loose housing system p&gt;0,05, however there was a tendency between the first component and age, where the older group showed a more defined personality p&lt;0,1. Other studies have showed that personality dimensions such as agreeableness, neuroticism and extraversion often exist in several species. Different personalities cope with stressful situations in different ways, making this topic relevant to the improvement of animal welfare.

Biological invasions are a major threat to biodiversity world wide with annual economic costs up to 1.4 trillion dollars. The round goby (Neogobius melanostomus) is a particularly fierce invader that threatens ecological function of the Baltic Sea. Individual variation in behavioral traits that remain constant through time and context have been identified as crucial factors for explaining different parts of the invasion process. For example, asocial behavior facilitates dispersal from high density populations and comes with fitness benefits in low conspecific density. The latter is especially relevant, in an invasion context, following the initial colonization of a novel environment when population density usually is low. This thesis investigates the role of individual variation in phenotypic traits on species invasions. The main focus is on the effects of sociability, activity and boldness, but also including aggression and physiological stress tolerance, on dispersal tendency and selection at invasion fronts. To do this, we studied four round goby populations in the Baltic Sea, two of the most recently established and two of the oldest populations. In 2012 we demonstrated that asocial, active and bold round gobies are overrepresented at invasion fronts. Two years later we showed that dispersal from the new populations was led by individuals with high activity levels, while in all populations larger individuals dispersed. We also determined the length of the socalled lag-phase, between colonization and spread, in both newly established populations. The end of the lag-phase is hypothesized being triggered by high population density in the harbors leading to dispersal and subsequen colonization of the surrounding areas by small asocial individuals. In our final experiment, we present evidence of stress coping styles in round gobies, in which more aggressive individuals are also more stress tolerant and vice versa. Though we found no connection between stress coping and population age, we found that mortality was unaffected by population density and that the gobies became more aggressive and stress tolerant when kept in high density. To conclude, we have shown that: 1) individuals with high levels of activity, boldness and asociality are common at invasion fronts; 2) a lag phase occurs between colonization and spread in round goby invasions; 3) asocial individuals drive the spread from high density populations at the invasion front and; 4) round gobies adapt to high densities with high aggression and stress tolerance.

No description available.

The aim of this study was to investigate the personality of bank vole using recaptures. Some behavioural types were determined (for example shy and bold) and influence of some factors on animal personality was defined (especially the daytime). The rate of repeatability of behaviour was also specified and the dependence of behaviour change on number of days between two captures was defined. Last, two types of tests used for animal personality were compared, indicating the differences between them.

Individuals engage in competitive and cooperative interactions with conspecifics. Furthermore, within any population of interacting individuals there are typically consistent differences among-individuals in behavioural traits. Understanding the importance of both these types of individual-specific behaviours allows us to understand why populations are structured as they are, why individuals show apparently limited behavioural flexibility, and how these elements link to population-level properties. I used extensive video camera monitoring of a population of wild field crickets (Gryllus campestris) to study the interactions and behaviours of uniquely identified individuals. I studied the shyness, activity and exploration of individuals of this population across contexts: from young to old and between captivity and the wild. This allowed me to confirm that individuals were relatively consistent across their adult lifetimes for all three traits, but only consistent between captivity and the wild for activity and exploration. I then found that high activity levels were positively related to high mating rates and short lifespans. Crucially, lifetime mating success was not related to activity level, indicating that the trade-off between lifespan and mating success was sufficient to allow variation in activity level to persist across generations. I also found that cricket social network structure is stable across generations despite the complete turnover of individuals every year. This social network structure influences sexual selection, with some male crickets heavily involved in networks of both pre- and post-copulatory competition, yet males are unable to use pre-copulatory competition to avoid post-copulatory competition. Additionally, positive assortment by mating rate between males and females may reduce the fitness of males with high mating rates, as they face stronger sperm competition. Finally, I used actor-based models to determine the factors predicting cricket social network structure and to test and reject the social-niche hypothesis for the maintenance of among-individual variation in behaviour. I also demonstrated that little else is needed in a stochastically changing network aside from positive assortment by mating rate to simulate a population with a similar skew in mating success to the one observed in the real cricket population. These results give insights into the importance of trade-offs and stochasticity in maintaining the extensive variation in the natural world.

Quantifying individual differences in behavior and the extent that behavior is influenced by circadian control is of paramount importance in behavioral ecology. In addition, the proximate mechanisms underlying behavior are also critical in order to obtain a more complete picture of how behavior evolves. Biogenic amines (BAs) are simple nitrogenous compounds derived from amino acids and have been consistently and extensively linked to behavior. For this study, we analyzed temporal patterns of BAs in relation to the antipredator (boldness) and aggressive behavior in female Agelenopsis pennsylvanica, a funnel-web spider. Using HPLC-ED, we compared behavioral responses to temporal patterns of octopamine and serotonin, two BAs known to influence behavior in invertebrates. Our results suggest that, while there was a clear diel cycling pattern of both aggression and boldness, BAs do not follow this same pattern, suggesting that oscillations in absolute levels of BAs are not the underpinnings of behavioral oscillations.

Numerous invertebrates have contributed to our understanding of the biology of learning and memory. In most cases, learning performance is documented for groups of individuals, and nearly always based on a single, typically binary, behavioural metric for a conditioned response. This is unfortunate for several reasons. Foremost, it has become increasingly apparent that invertebrates exhibit inter-individual differences in many aspects of their behaviour, and also that the conditioned response probability for an animal group does not adequately represent the behaviour of individuals in classical conditioning. Furthermore, a binary response character cannot yield a graded score for each individual. We also hypothesise that due to the complexity of a conditioned response, a single metric need not reveal an individual’s full learning potential. In this paper, we report individual learning scores for freely moving adult male crickets (Gryllus bimaculatus) based on a multi-factorial analysis of a conditioned response. First, in an absolute conditioning paradigm, we video-tracked the odour responses of animals that, in previous training, received either odour plus reward (sugar water), reward alone, or odour alone to identify behavioural predictors of a conditioned response. Measures of these predictors were then analysed using binary regression analysis to construct a variety of mathematical models that give a probability for each individual that it exhibited a conditioned response (Presp). Using standard procedures to compare model accuracy, we identified the strongest model which could reliably discriminate between the different odour responses. Finally, in a differential appetitive olfactory paradigm, we employed the model after training to calculate the Presp of animals to a conditioned, and to an unconditioned odour, and from the difference a learning index for each animal. Comparing the results from our multi-factor model with a single metric analysis (head bobbing in response to a conditioned odour), revealed advantageous aspects of the model. A broad distribution of model-learning scores, with modes at low and high values, support the notion of a high degree of variation in learning capacity, which we discuss.

No description available.

No description available.