| 1. |
- Andersson, Martin O., et al.
(författare)
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Molecular detection of Babesia capreoli and Babesia venatorum in wild Swedish roe deer, Capreolus capreolus
- 2016
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Ingår i: Parasites & Vectors. - : Springer Science and Business Media LLC. - 1756-3305. ; 9:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: The epidemiology of the zoonotic tick-transmitted parasite Babesia spp. and its occurrence in wild reservoir hosts in Sweden is unclear. In European deer, several parasite species, including Babesia capreoli and the zoonotic B. venatorum and B. divergens has been reported previously. The European roe deer, Capreolus capreolus, is an important and common part of the indigenous fauna in Europe, as well as an important host for Ixodes ricinus ticks, the vector of several Babesia spp. in Europe. Here, we aimed to investigate the occurrence of Babesia spp. in roe deer in Sweden. Findings: Roe deer (n = 77) were caught and sampled for blood. Babesia spp. was detected with a PCR assay targeting the 18S rRNA gene. The prevalence of Babesia spp. was 52 %, and two species were detected; B. capreoli and B. venatorum in 44 and 7.8 % of the individuals, respectively. Infection occurred both in summer and winter. Conclusions: We showed that roe deer in Sweden, close to the edge of their northern inland distributional range, are infected with Babesia spp. The occurrence of B. venatorum in roe deer imply that it is established in Sweden and the zoonotic implication of this finding should be regarded to a greater extent in future.
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| 2. |
- Fallahshahroudi, Amir, 1981-
(författare)
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Domestication Effects on the Stress Response in Chickens : Genetics, Physiology, and Behaviour
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Animal domestication, the process where animals become adapted to living in proximity to humans, is associated with the alteration of multiple traits, including decreased fearfulness and stress response. With an estimated population of 50 billion, the domesticated chicken is the most populous avian species in the world. Hundreds of chicken breeds have been developed for meat and egg production, hobby or research purposes. Multidirectional selection and the relaxation of natural selection in captivity have created immense phenotypic diversity amongst domesticates in a relatively short evolutionary time. The extensive phenotypic diversity, existence of the wild ancestor, and feasibility of intercrossing various breeds makes the chicken a suitable model animal for deciphering genetic determinants of complex traits such as stress response. We used chicken domestication as a model to gain insights about the mechanisms that regulate stress response in an avian species. We studied behavioural and physiological stress response in the ancestral Red Junglefowl and one of its domesticated progenies, White Leghorn. An advanced intercross between the aforementioned breeds was later used to map genetic loci underlying modification of stress response. The general pattern of the stress response in chickens was comparable with that reported in mammals, however we identified distinctive differences in the stress modulatory pathways in chickens. We showed that changes in the expression levels of several stress modulatory genes in the brain, the pituitary and the adrenal glands underlie the observed modified stress response in domesticated chickens. Using quantitative trait loci (QTL) mapping, several QTL underlying stress induced corticosterone, aldosterone and baseline dehydroepiandrosterone (DHEA) levels were detected. As a next step, we combined QTL mapping with gene expression (eQTL) mapping and narrowed two QTL down to the putative causal genes, SERPINA10 and PDE1C. Both of these genes were differentially expressed in the adrenal glands of White Leghorn and the Red Junglefowl, had overlapping eQTL with hormonal QTL, and their expression levels in the adrenal glands were correlated with plasma levels of corticosterone and al-dosterone. These two genes thus serve as strong candidates for further functional investigation concerning modification of the stress response during domestication. This dissertation increase the knowledge about genetics and physiology of the stress response in an avian species and its modification during domestication. Our findings expand the basic knowledge about the stress response in chicken, which can potentially be used to improve welfare through appropriate genetic selection.
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| 3. |
- Kylin, Henrik
(författare)
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Finns det slemsvampar i havet?
- 2013
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Ingår i: Fauna och flora. - : Sveriges Lantbruksuniversitet. - 0014-8903. ; 108:1, s. 9-9
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 4. |
- Sundman, Ann-Sofie, 1982-
(författare)
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Dog behaviour : Intricate picture of genetics, epigenetics, and human-dog relations
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Dogs, Canis familiaris, share the lives of humans all over the world. That dogs, and the behavior of dogs, are of interest to many is therefore no surprise. In this thesis, the main aim has been to identify factors that affect dogs’ behaviours.The dog, Canis familiaris, is our first domesticated animal. Since domestication, various types of dogs have developed through adaptation to an environment shared with humans and through our selective breeding, resulting in a unique variation in morphology and behaviour. Although there is an individual variation in the behaviour of dogs, there is also a difference between breeds. Moreover, selection during the last decades has split some breeds into divergent types. Labrador and golden retrievers are divided into a common type, for show and companionship, and a field type, for hunting. By comparing the breed types, we can study the effects of recent selection. In Paper I, we investigate differences in general behavioural traits between Labrador and golden retriever and between common and field type within the two breeds by using results from the standardized behaviour test Dog Mentality Assessment. There were differences between breeds and types for all behavioural traits. However, there was also an interaction between breed and type. Thus, a common/field-type Labrador does not behave like a common/field-type golden retriever. Even though they have been selected for similar traits, the selection has affected the general behavioural traits differently in the two breeds.In paper II, we were interested in dogs’ human-directed social skills. Dogs have a high social competence when it comes to humans. Two experiments commonly used to study these skills are the problem-solving test, where dogs’ human-directed behaviours when faced with a problem are measured, and the pointing test, where dogs are tested on how well they understand human gestures. We compared the social skills of German shepherds and Labrador retrievers, and of common- and field-type Labradors. Labradors were more successful in the pointing test and German shepherds stayed closer to their owners during the problem solving. Among Labrador types, the field type had more human eye contact than the common type. Importantly, when comparing the two experiments, we found no positive correlations between the problem-solving test and the pointing test, suggesting that the two tests measure different aspects of human-directed social behaviour in dogs.A previous study has identified two suggestive genetic regions for human-directed social behaviours during the problem-solving test in beagles. In paper III, we show that these SNPs are also associated to social behaviours in Labrador and golden retrievers. Moreover, the Labrador breed types differed significantly in allele frequencies. This indicates that the two SNPs have been affected by recent selection and may have a part in the differences in sociability between common and field type.The behaviour of dogs cannot simply be explained by genetics, there is also an environmental component. In paper IV, we study which factors that affect long-term stress in dogs. Long-term cortisol can be measured by hair samples. We found a clear synchronization in hair cortisol concentrations between dogs and their owners. Neither dogs’ activity levels nor their behavioural traits affected the cortisol, however, the personality of the owners did. Therefore, we suggest that dogs mirror the stress level of their owners.The mediator between genes and the environment is epigenetics, and one epigenetic factor is DNA methylation. In paper V, we compared methylation patterns of wolves and dogs as well as dog breeds. Between both wolves and dogs and among dogs there were substantial differences in methylated DNA regions, suggesting that DNA methylation is likely to contribute to the vast variation among canines. We hypothesize that epigenetic factors have been important during domestication and in breed formation.In this thesis, I cover several aspects on how dogs’ behaviours can be affected, and paint an intricate picture on how genetics, epigenetics, and human-dog relations forms dog behaviour.
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| 5. |
- Sundman, Ann-Sofie, et al.
(författare)
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Similar recent selection criteria associated with different behavioural effects in two dog breeds
- 2016
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Ingår i: Genes, Brain and Behavior. - : Wiley-Blackwell Publishing Inc.. - 1601-1848 .- 1601-183X. ; 15:8, s. 750-756
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Tidskriftsartikel (refereegranskat)abstract
- Selection during the last decades has split some established dog breeds into morphologically and behaviourally divergent types. These breed splits are interesting models for behaviour genetics since selection has often been for few and well-defined behavioural traits. The aim of this study was to explore behavioural differences between selection lines in golden and Labrador retriever, in both of which a split between a common type (pet and conformation) and a field type (hunting) has occurred. We hypothesized that the behavioural profiles of the types would be similar in both breeds. Pedigree data and results from a standardized behavioural test from 902 goldens (698 common and 204 field) and 1672 Labradors (1023 and 649) were analysed. Principal component analysis revealed six behavioural components: curiosity, play interest, chase proneness, social curiosity, social greeting and threat display. Breed and type affected all components, but interestingly there was an interaction between breed and type for most components. For example, in Labradors the common type had higher curiosity than the field type (F1,1668 = 18.359; P < 0.001), while the opposite was found in goldens (F1,897 = 65.201; P < 0.001). Heritability estimates showed considerable genetic contributions to the behavioural variations in both breeds, but different heritabilities between the types within breeds was also found, suggesting different selection pressures. In conclusion, in spite of similar genetic origin and similar recent selection criteria, types behave differently in the breeds. This suggests that the genetic architecture related to behaviour differs between the breeds.
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| 6. |
- Arshamian, Artin, et al.
(författare)
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A mammalian blood odor component serves as an approach-avoidance cue across phylum border - from flies to humans
- 2017
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- Chemosignals are used by predators to localize prey and by prey to avoid predators. These cues vary between species, but the odor of blood seems to be an exception and suggests the presence of an evolutionarily conserved chemosensory cue within the blood odor mixture. A blood odor component, E2D, has been shown to trigger approach responses identical to those triggered by the full blood odor in mammalian carnivores and as such, is a key candidate as a food/alarm cue in blood. Using a multidisciplinary approach, we demonstrate that E2D holds the dual function of affecting both approach and avoidance behavior in a predator-prey predicted manner. E2D evokes approach responses in two taxonomically distant blood-seeking predators, Stable fly and Wolf, while evoking avoidance responses in the prey species Mouse. We extend this by demonstrating that this chemical cue is preserved in humans as well; E2D induces postural avoidance, increases physiological arousal, and enhances visual perception of affective stimuli. This is the first demonstration of a single chemical cue with the dual function of guiding both approach and avoidance in a predator-prey predicted manner across taxonomically distant species, as well as the first known chemosignal that affects both human and non-human animals alike.
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| 7. |
- Burman, Joseph, et al.
(författare)
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Revealing hidden species distribution with pheromones: the caseof Synanthedon vespiformis (Lepidoptera: Sesiidae) in Sweden
- 2016
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Ingår i: Journal of Insect Conservation. - : Springer Science and Business Media LLC. - 1366-638X .- 1572-9753. ; 20:1, s. 11-21
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Tidskriftsartikel (refereegranskat)abstract
- Synanthedon vespiformis L. (Lepidoptera:Sesiidae) is considered a rare insect in Sweden, discoveredin 1860, with only a few observations recorded until a sexpheromone attractant became available recently. This studydetails a national survey conducted using pheromones as asampling method for this species. Through pheromonetrapping we captured 439 specimens in Southern Sweden at77 sites, almost tripling the number of previously reportedrecords for this species. The results suggest that S. vespiformisis truly a rare species with a genuinely scattereddistribution, but can be locally abundant. Habitat analyseswere conducted in order to test the relationship betweenhabitat quality and the number of individuals caught. InSweden, S. vespiformis is thought to be associated with oakhosts, but our attempts to predict its occurrence by theabundance of oaks yielded no significant relationships. Wetherefore suggest that sampling bias and limited knowledgeon distribution may have led to the assumption that thisspecies is primarily reliant on oaks in the northern part ofits range, whereas it may in fact be polyphagous, similar toS. vespiformis found as an agricultural pest in Central andSouthern Europe. We conclude that pheromones canmassively enhance sampling potential for this and otherrare lepidopteran species. Large-scale pheromone-basedsurveys provide a snapshot of true presences and absencesacross a considerable part of a species national distributionrange, and thus for the first time provide a viable means ofsystematically assessing changes in distribution over timewith high spatiotemporal resolution.
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| 8. |
- Jarnemo, Anders, et al.
(författare)
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Managing landscapes for multiple objectives : Alternative forage can reduce the conflict between deer and forestry
- 2014
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Ingår i: Ecosphere. - Washington : Ecological Society of America. - 2150-8925 .- 2150-8925. ; 5:8
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Tidskriftsartikel (refereegranskat)abstract
- Deer (Cervidae) cause considerable damage to forest plantations, crops, and protected habitats. The most common response to this damage is to implement strategies to lower population densities. However, lowering deer density may not always be desirable from hunting, recreational, or conservation perspectives. Therefore, knowledge is needed about additional factors beyond deer density that affect damage levels, and management actions that consider competing management goals. We studied the relationships between levels of bark-stripping by red deer (Cervus elaphus) on Norway spruce (Picea abies) and (1) relative deer density indices (pellet group count and deer harvest data), (2) availability of alternative natural forage (cover of forage species) and (3) proportion forest in the landscape, both at a forest stand scale and at a landscape scale. Extensive variation in damage level was evident between the six study areas. On a stand scale, the proportion of spruce damaged was positively related to pellet group density, indicating the importance of local deer usage of stands. In addition, available alternative forage in the field layer within spruce stands and proportion forest surrounding stands was negatively related to damage level. On the landscape scale, damage level was negatively related to availability of forage in the field and shrub layers and proportion forest, but was not related to any of the relative deer density indices. Increasing alternative forage may thus decrease damage and thereby reduce conflicts. Additionally, the proportion of forest in the landscape affects damage levels and should thus be considered in landscape planning and when forecasting damage risk. The relationship between local deer usage of stands and damage level suggests that future studies should try to separate the effects of local deer usage and deer density. © 2014 Jarnemo et al.
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| 9. |
- Rice, William R, et al.
(författare)
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Genomic clues to an ancient asexual scandal.
- 2007
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Ingår i: Genome Biology. - : Springer Science and Business Media LLC. - 1465-6906 .- 1474-760X. ; 8:12
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Tidskriftsartikel (refereegranskat)abstract
- Despite abandoning meiosis, the bdelloid rotifers have persisted for millions of years and given rise to hundreds of species. Several mechanisms - allelic variants with different functions, high effective population size, and resistance to radiation - may contribute to their success.Bdelloid rotifers are diploid aquatic microinvertebrates that live in fresh or brackish water, especially in ephemeral habitats prone to periodic desiccation. They are the only well documented lineage that has eliminated meiosis yet has persisted for many millions of years (more than 35 million years [1]) and undergone an adaptive radiation - nearly 400 species in three families. Maynard Smith [2] referred to them as an "evolutionary scandal" because they are the exception to the usual pattern that asexual lineages die out before undergoing extensive speciation.The fact that asexuals are composed entirely of offspring-producing females gives them an intrinsic demographic advantage over sexual competitors whenever males do not help to produce offspring (referred to as the 'two-fold cost of sex' or the 'cost of producing males'). Evolutionary theory predicts, however, that obligate asexuals have a long-term evolutionary disadvantage, compared with sexuals, owing to a more pronounced 'Hill-Robertson effect', a reduction in the efficacy of natural selection that occurs because finite populations accumulate associations of linked genes (haplotypes) that interfere with selection [3, 4] (Figure 1).Figure 1The effect of genetic linkage on the effectiveness of selection. Consider two closely linked single nucleotide polymorphisms (SNPs A and B) with one of the 'alleles' at each site favored by selection (denoted by a superscript +). Selection acts more weakly on the 'interfering' haplotypes (A+B- and A-B+), where positive selection on one SNP is counterbalanced by negative selection on the other, compared with the 'reinforcing' haplotypes (A+B+ and A-B-), where selection on the two SNPs is complementary. This disparity causes interfering haplotypes to persist longer after they have accumulated by chance in finite populations. See Box 1 for further details.The Hill-Robertson effect arises when selection acts simultaneously at multiple linked sites (Figure 1). In this case, the fate of a mutation depends not only on its own selective value but also on that of its genetic backgrounds. Selection on genetic backgrounds introduces 'noise', which makes selection on a mutation less efficient. A similar interaction occurs between selection and random genetic drift, with smaller population sizes increasing the noise generated by drift. The cost of the Hill-Robertson effect in asexuals can be expressed as a reduced effective population size (N e , the size of an idealized, random-mating population with only chance fluctuations in family sizes) compared with the actual population size (census size, N; see Box 1 for further details). Because the strength of the Hill-Robertson effect increases with tighter linkage, non-meiotic species like bdelloid rotifers, in which 'interfering' haplotypes cannot be routinely broken up, should have a much reduced N e compared with their sexual competitors with similar census sizes, and should hence experience less effective selection. All else being equal, the bdelloids' ability to compete with sexuals should erode over time, leading to their eventual extinction. This has not happened, so the bdelloids must have one or more compensating advantages. Several recent studies indicate how bdelloids may have achieved their "scandalous" status.
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| 10. |
- Gavrilets, Sergey, et al.
(författare)
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The evolution of female mate choice by sexual conflict
- 2001
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Ingår i: Proceedings of the Royal Society of London Series B. - London : The Roylal Society. - 0080-4649 .- 0962-8452 .- 1471-2954. ; 268:1466, s. 531-539
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Tidskriftsartikel (refereegranskat)abstract
- Although empirical evidence has shown that many male traits have evolved via sexual selection by female mate choice, our understanding of the adaptive value of female mating preferences is still very incomplete. It has recently been suggested that female mate choice may result from females evolving resistance rather than attraction to males, but this has been disputed. Here, we develop a quantitative genetic model showing that sexual conflict over mating indeed results in the joint evolution of costly female mate choice and exaggerated male traits under a wide range of circumstances. In contrast to traditional explanations of costly female mate choice, which rely on indirect genetic benefits, our model shows that mate choice can be generated as a side–effect of females evolving to reduce the direct costs of mating.
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