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  • 1. Andersson, P L
    et al.
    Berg, A H
    Bjerselius, Rickard
    Norrgren, L
    Olsén, K Håkan
    Olsson, P E
    Örn, S
    Tysklind, M
    Bioaccumulation of selected PCBs in zebrafish, three-spined stickleback, and Arctic char after three different routes of exposure2001In: Archives of Environmental Contamination and Toxicology, ISSN 0090-4341, E-ISSN 1432-0703, Vol. 40, no 4, p. 519-530Article in journal (Refereed)
    Abstract [en]

    The uptake and elimination of 20 structurally diverse tetra- to heptachlorinated biphenyls were studied in zebrafish (Danio rerio), three-spined stickleback (Gasterosteus aculeatus), and Arctic char (Salvelinus alpinus). The polychlorinated biphenyls (PCBs) were administered to the fish through food, intraperitoneal injection of peanut oil, or intraperitoneal implantation of silicone capsules. The retention of the PCBs in fish exposed through their diet was related with the substitution patterns of the compounds. Ortho-substituted congeners with no unsubstituted meta-para positions had high biomagnification potential. PCBs with low biomagnification all had adjacent vicinal hydrogens, indicating that congeners with this feature may have been metabolically eliminated. The retention characteristics of the PCBs in the diet-exposed and the injected zebrafish were similar. The pattern of congeners in Arctic char indicates that they have a lower capacity to metabolize PCBs compared to three-spined sticklebacks and zebrafish. The levels in the fish exposed to the PCBs through a silastic implant were negatively correlated with the hydrophobicity of the congeners. Most probably congener-specific release rates of the PCBs from the implants mask their retention characteristics. It is suggested that food, mimicking the natural intake route, should be used in PCB exposure studies to validate extrapolations to natural situations.

  • 2.
    Archer, Amena
    et al.
    BioNut, Karolinska Institutet.
    Srinivas Kitambi, Satish
    BioNut, Karolinska Institutet.
    Hallgren, Stefan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Pedrelli, Matteo
    BioNut, Laboratoriemedicin, Karolinska Institutet.
    Olsén, Håkan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Mode, Agneta
    BioNut, Karolinska Institutet.
    Gustafsson, Jan-Åke
    BioNut, Karolinska Institutet; Dept. Biology and Biochemistry, University of Houston.
    The Liver X-Receptor (Lxr) Governs Lipid Homeostasis in Zebrafish during Development2012In: Open journal of endocrine and metabolic diseases, ISSN 2165-7424, Vol. 2, no 4, p. 74-81Article in journal (Refereed)
    Abstract [en]

    The liver-X-receptors (LXRs) act as cholesterol sensors and participate in the regulation of lipid and cholesterol metabolism. The objective of this study was to determine the role of LXR during development using the zebrafish model. By in situ hybridization we showed distinct expression of lxr in the brain and the retina in the developing and adult zebrafish. Lxr ligand activation affected the expression of genes involved in lipid metabolism in zebrafish adult brain and eye as well as in zebrafish embryos. Morpholino knock down of lxr resulted in an overall impaired lipid deposition as determined by oil red O staining particularly in the head and around the eyes, and to significantly elevated levels of both total and free cholesterol in the yolk of lxr morphant embryos. The expression of genes involved in lipid and cholesterol metabolism was also changed in the lxr morphants. Furthermore, alcian blue staining revealed malformation of the pharyngeal skeleton in the lxr morphant. Our data show that Lxr is an important component of the regulatory network governing the lipid homeostasis during zebrafish development, which in turn may support a role of Lxr for normal development of the central nervous sytem, including the retina.

  • 3. Bjerselius, Rickard
    et al.
    Lundstedt-Enkel, Katrin
    Olsén, K Håkan
    Mayer, Ian
    Dimberg, K
    Male goldfish reproductive behaviour and physiology are severely affected by exogenous exposure to 17 beta-estradiol2001In: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 53, no 2, p. 139-152Article in journal (Refereed)
    Abstract [en]

    Mature male goldfish were exposed to different concentrations of the natural hormone 17 beta -estradiol (El). Two methods of exposure were employed, via ingestion at 0, 1, 10 and 100 ug/g food and via the water at 0, 1 and 10 mug/l. The fish were exposed fur 74-28 days during the spawning period. The males were then paired with an artificially induced, spawning female and their sexual behaviour was observed during a 15 min period. The physiological status of the fish was also examined with respect to GSI. presence of milt and spawning tubercles and the blood plasma concentration of E-2. Despite the relatively short exposure period. exposure to physiological levels of E-2 was shown to severely affect the male goldfish reproductive behaviour and physiology. In conclusion, the results from this study and the ability to interpret the effects on this well-studied species, show that the effects of E-2, and possibly other estrogenic EDCs have severe effects at several vital levels of male goldfish reproduction. The results also suggests that the hormone E-2 can act as an endocrine disrupting chemical (EDC) in the environment.

  • 4.
    Bonow, Madeleine
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Olsén, HåkanSödertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.Svanberg, IngvarUppsala universitet.
    Historical Aquaculture in Northern Europe2016Collection (editor) (Refereed)
    Abstract [en]

    How were fishponds introduced, farmed and spread in Scandinavia and the Baltic Region in early modern times? What was their economic, social and religious importance? Which fish species were significant and why?

    This book uncovers a long, now broken, tradition that barely left traces in the written record or physical environment. Its broad and multidisciplinary scope highlights the situation from medieval times until the late nineteenth century. Besides Scandinavia and the Baltic States, insights from England are also introduced.

    Several socio-cultural domains have been identified: late medieval monastic fishponds; late medieval aristocratic fishponds associated with castles and manors; seventeenth and eighteenth century ponds rectory ponds as well as urban ponds from the seventeenth century to the nineteenth century.

  • 5. Carlsson, J
    et al.
    Carlsson, J E L
    Olsén, K Håkan
    Södertörn University, School of Chemistry, Biology, Geography and Environmental Science.
    Hansen, M M
    Eriksson, T
    Nilsson, J
    Kin-biased distribution in brown trout: an effect of redd location or kin recognition?2004In: Heredity, ISSN 0018-067X, E-ISSN 1365-2540, Vol. 92, no 2, p. 53-60Article in journal (Refereed)
    Abstract [en]

    A wide range of animals have been reported to show kin-biased behaviours, such as reduced aggressiveness and increased food sharing among relatives. However, less is known about whether wild animals also associate with relatives under natural conditions, which is a prerequisite to facilitate kin-biased behaviours and hence kin selection. We tested, by means of microsatellite polymorphism, correlations between pair-wise relatedness and pair-wise metric distance in wild brown trout ( Salmo trutta L.) under natural conditions in two streams. Our data show that young-of-the-year as well as older trout found close together also had a higher genetic relatedness in one of the two streams, whereas no relationship was found in the other stream. Very few half and full siblings were found in the second stream and under these conditions it is unlikely that kin-biased behaviours will receive positive selection. We discuss the underlying mechanisms for the observed structure and we specifically address the issue of whether the grouping of related individuals could reflect dispersal from the same spawning redds, or if it reflects active association with relatives, possibly conferring kin-selected advantages.

  • 6. Greenberg, L A
    et al.
    Hernnäs, B
    Brönmark, D
    Dahl, J
    Eklöv, A
    Olsén, K Håkan
    Södertörn University, Avdelning Naturvetenskap.
    Effects of kinship on growth and movements of brown trout in field enclosures2002In: Ecology of Freshwater Fish, ISSN 0906-6691, E-ISSN 1600-0633, Vol. 11, no 4, p. 251-259Article in journal (Refereed)
    Abstract [en]

    The effect of kinship on growth and use of space by individually PIT-tagged 1+ brown trout was studied for 11 weeks in eight stream enclosures. Each enclosure consisted of two sections, separated by a region containing PIT-detecting antennae, which enabled us to measure use of sections by all individuals. Two types of sibling groups were tested, a single sibling group, F1, consisting of four individuals that were reared together in hatchery tank 'a' (F1(a)) plus four additional siblings of the same family but raised in hatchery tank 'b' (F1(b)), and a mixed sibling group, consisting of four F1(a) individuals plus four siblings from a second family, F2. Based on kin theory and earlier laboratory studies, we expected that growth of the F1(a) individuals in the single sibling group to be greater than that of F1(a) individuals in the mixed family sibling group, but instead we found just the opposite. The variance of growth did not differ between treatments. Nor was there a difference in time F1(a) individuals spent together when they were in mixed versus single sibling groups. We did find that F1(a) individuals changed habitat more frequently than F2 individuals in the mixed sibling group but less frequently than F1(b) in the single sibling groups. Thus, our predictions based on kin theory for growth and behavior of brown trout were not supported by our data, and we suggest that the role of kin recognition for the ecology of salmonids deserves further attention.

  • 7.
    Hallgren, Stefan
    et al.
    Södertörn University, School of Life Sciences.
    Linderoth, Maria
    Olsén, K Håkan
    Södertörn University, School of Life Sciences.
    Inhibition of cytochrome p450 brain aromatase reduces two male specific sexual behaviours in the male Endler guppy (Poecilia reticulata)2006In: General and Comparative Endocrinology, ISSN 0016-6480, E-ISSN 1095-6840, Vol. 147, no 3, p. 323-328Article in journal (Refereed)
    Abstract [en]

    In mammalian and avian vertebrate groups, androgens act as controlling agents on male aggression and courtship behaviour by their conversion to oestrogens by cytochrome P450 aromatase in well-defined brain regions. Despite the fact that bony fishes have exceptionally high brain aromatase activity, little is known about it's possible regulatory effects on the reproductive behaviours of teleosts. In this study, Endler guppy males (Poecilia reticulata) were subjected to 26-29 days of 24-h exposure to two different concentrations (15 and 100 pg/L) of the aromatase inhibitor fadrozole in the water. Compared with the control males, two of three courtship activities in males exposed to the higher concentration were reduced when they were paired with receptive stimulus females. Reduction in brain aromatase activity was confirmed in both exposed groups with the use of the tritiated water assay.

  • 8.
    Hallgren, Stefan
    et al.
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Olsén, K Håkan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Effects on Guppy Brain Aromatase Activity Following Short-Term Steroid and 4-Nonylphenol Exposures2010In: Environmental Toxicology, ISSN 1520-4081, E-ISSN 1522-7278, Vol. 25, no 3, p. 261-271Article in journal (Refereed)
    Abstract [en]

    Brain estrogen production, performed by the enzyme aromatase, can be disrupted/affected in teleost fish exposed to endocrine disruptors found in polluted aquatic environments. The guppy (Poecilia reticulata) was previously studied and confirmed to suffer negative effects on reproductive behaviors following inhibition of the brain aromatase reaction. Here adult guppies (Poecilia reticulata) of both genders were subjected to known endocrine disruptors: the androgen androstenedione (A), the synthetic estrogen 17 alpha-ethinylestradiol (EE2), and the estrogenic surfactant 4-nonylphenol (NP), at high (50 mu g/L) and at environmentally relevant concentrations (10 ng/L EE2, 5 mu g/L NP, and 0.7 mu g/L A) for 2 weeks followed by measurements of brain aromatase activity (bAA). In the adult males, bAA was stimulated by A and EE2 at 50 mu g/L. Female activity was also stimulated by the higher estrogenic treatment. At environmentally relevant concentrations only the EE2 treatment affected bAA, and only in males. The alkylphenolic substance NP produced no effect in either of the experiments, not on males nor females. The results indicate that short-term steroid treatments have stimulatory effects on guppy brain aromatase even at concentrations that can be found in the environment. We thus suggest bAA of adult guppies to be a suitable bioindicator of endocrine disruptors.

  • 9.
    Hallgren, Stefan
    et al.
    Södertörn University College, School of Life Sciences.
    Olsén, K Håkan
    Södertörn University College, School of Life Sciences.
    Impacts of synthetic oestrogen and antioestrogen treatments on courtship and mating behaviours in male guppies (Poecilia reticulata)Manuscript (preprint) (Other academic)
    Abstract [en]

    Understanding the neuroendocrinological mechanisms behind reproductive behaviour is fundamental when studying endocrine disruption. Neuroestrogen production is a key step in the activation of reproductive behaviours among vertebrates. The actions of estrogens are transmitted through estrogen receptors (ERs) in distinct brain nuclei. Here we report alterations in reproductive behaviours in guppy males following 55-day food treatments with the antiestrogen fulvestrant (ICI) and the synthetic oestrogen 17α-ethinylestradiol (EE2). Male courtship and mating attempts were severely reduced in EE2 treated males after both 27-30 and 41-55 days of treatment when paired with females. ICI treatment gave a significant reduction in the frequency of sigmoid display behaviour after 27-30 days of treatment, and an almost 2.5-fold increase in gonopodium thrusting after 41-55 days of treatment. ICI treated males also decreased their frequency in successful mating attempts in comparison to the control males. The neurological effects of ICI were confirmed by Real Time-PCR analysis for brain aromatase and ERα gene expression. ICI treatment suppressed aromatase expression to 64% and stimulated ERα gene expression by over 300%. These results indicate that oestrogen action via ERs may play an important role for the complete display of male courtship and mating behaviour in the guppy. The results also suggest that local steroids are involved in regulating brain aromatase expression and that the negative effects of EE2 on sexual behaviour are linked via endocrine disruption of gonadal function.

  • 10.
    Hallgren, Stefan
    et al.
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Volkova, Kristina
    Södertörn University, School of Life Sciences, Environmental science.
    Reyhanian, Nasim
    Södertörn University, School of Life Sciences, Environmental science.
    Olsén, K Håkan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Porsch Hällström, Inger
    Södertörn University, School of Life Sciences, Environmental science.
    Anxiogenic behaviour induced by 17α-ethynylestradiol in male guppies (Poecilia reticulata)2011In: Fish Physiology & Biochemistry, ISSN 0920-1742, E-ISSN 1573-5168, Vol. 37, no 4, p. 911-918Article in journal (Refereed)
    Abstract [en]

    Behaviour studies are used in toxicology research as they are excellent tools to measure physiological end-points caused by exogenous chemicals. In mammals both reproductive and non-reproductive behaviours have been used for a long period of time, whereas in teleost fishes non-reproductive behaviours have received little attention compared to reproductive behaviours. Recent advances in measuring stress related behaviours in zebrafish have provided additional tools to understand behaviour toxicology in fish. One species with well documented reproductive behaviour disturbed by different toxicants is the guppy, which is better suited than zebrafish for reproductive behaviour studies and therefore might be a better model organism for comparative behaviour studies in fish toxicology. Here we report new applications for non-reproductive behaviours in guppy and test these behaviours on males treated with the endocrine disruptor 17α-ethynylestradiol at environmentally relevant concentrations. 17α-ethynylestradiol increased freezing and bottom-dwelling when fish were placed in a non-familiar aquarium, but did not significantly affect shoaling behaviour. These results are similar to the anxiogenic behaviours seen in rats treated perinatally with 17α-ethynylestradiol and add more concern to the impacts of endocrine disruptors on aquatic wildlife.

  • 11.
    Hellström, Gustav
    et al.
    SLU, Umeå.
    Prestegaard, Tore
    SLU, Uppsala .
    Dannewitz, Johan
    SLU, Uppsala.
    Olsén, Håkan
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science. Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Sperm from pheromone primed brown trout (Salmo trutta L.) produce more larvae2013In: Fish Physiology & Biochemistry, ISSN 0920-1742, E-ISSN 1573-5168, Vol. 39, no 3, p. 471-478Article in journal (Refereed)
  • 12. Jaensson, Alia
    et al.
    Olsén, K Håkan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Effects of copper on olfactory-mediated endocrine responses and reproductive behaviour in mature male brown trout Salmo trutta parr to conspecific females2010In: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 76, no 4, p. 800-817Article in journal (Refereed)
    Abstract [en]

    In the present study, the effects of copper (CuSO4) on the ability of mature male brown trout Salmo trutta parr to detect and react both physiologically and behaviourally to female pheromones were studied. The study was composed of two parts. In the first experiment, priming effects of the female pheromone prostaglandin F-2 alpha (PGF(2 alpha)) were evaluated by determining the amount of milt produced and the blood plasma levels of 11-ketotestosterone (11-KT) and 17 alpha,20 beta-dihydroxy-4-pregnen-3-one (17,20 beta-P) after the PGF(2 alpha) exposure. In the second experiment, male parr were placed in a large stream tank together with a group of adult males and ovulated females and their individual behaviours were recorded. In the priming experiment, the amount of expressible milt was significantly lower, less than half, in groups exposed during 4 days to 10 or 100 mu g l-1 copper compared with control parr only exposed to water. No significant differences were observed in plasma levels of 11-KT and 17, 20 beta-P. During the behavioural experiment, exposed parr spent less time with the female and had a lower number of courting events. Blood plasma levels of 11-KT were, however, significantly higher in the group exposed to 100 mu g l-1 copper compared with the control group. Furthermore, the exposed group spent significantly less time swimming upstream than did the control group. The present study demonstrates that exposure to copper affects reproductive behaviours and endocrinology of S. trutta male parr.

  • 13.
    Jaensson, Alia
    et al.
    Södertörn University, School of Life Sciences.
    Olsén, K. Håkan
    Södertörn University, School of Life Sciences.
    Prolonged cypermthrin exposure increases sex steroid plasma hormone levels in mature male brown trout (Salmo trutta) parr in spawning groupsIn: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514Article in journal (Refereed)
  • 14.
    Jaensson, Alia
    et al.
    Södertörn University, School of Life Sciences. Uppsala University.
    Scott, Alexander P.
    Moore, Andrew
    Kylin, Henrik
    Olsén, K Håkan
    Södertörn University, School of Life Sciences.
    Effects of a pyrethroid pesticide on endocrine responses to female odours and reproductive behaviour in male parr of brown trout (Salmo trutta L.)2007In: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 81, no 1, p. 1-9Article in journal (Refereed)
    Abstract [en]

    Reproductive behaviour of brown trout (Salmo trutta L.) from an anadromous stock was Studied in a large stream water aquarium. Four adult males and two ovulated females were placed in the aquarium together with eight mature male parr. Four of the parr were exposed during the previous 4 days to two concentrations (0.1 or 1.0 mu g l(-1)) of the pyrethroid pesticide cypermethrin (a disrupter of olfactory receptor function) and four of the parr to the solvent ethanol. The behaviour of all fish was followed for 24 h and then blood and milt was collected. Exposure to the higher concentration of cypermethrin disturbed the reproductive behaviour of the parr. They displayed fewer courting events, spent less time near the nesting females and had lower volumes of strippable milt. They also had significantly lower amounts of 11-ketotestosterone (11-KT) in the blood plasma than the control roup. The higher cypermethrin group also had significantly lower levels of all these variables than the 9 lower cypermethrin group, apart from strippable milt that showed no significant differences between two groups. No significant differences in non-reproductive behaviours were observed between any of the groups. In the control fish, there were significant positive Correlations between (a) the number of courting events and the amount of time spent near the female, (b) blood plasma levels of 17 alpha,20 beta-dihydroxy-4-pregnen-3-one (17,20 beta-P) and time spent near the female and (c) plasma levels of 17,20 beta-P and the number of courting events. Further, in control fish, higher plasma levels of 17,20 beta-P were observed in part-interacting with a female compared to those with no female contacts. A priming experiment confirmed a previous study that cypermethrin damages olfactory reception. Parr exposed to cypermethrin had significantly lower blood plasma levels of 17,20 beta-P and 11-KT than control males after exposure to ovarian fluid and urine (known to contain reproductive priming pheromones). When ethanol-exposed males were exposed to ovarian fluid and urine they had significantly higher plasma levels of 17,20 beta-P compared to those exposed to water only.

  • 15.
    Janson, Sven
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Wouters, Johanna
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Bonow, Madeleine
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Geography.
    Svanberg, Ingvar
    Uppsala University.
    Olsén, K. Håkan
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Population genetic structure of crucian carp (Carassius carassius) in man-made ponds and wild populations in Sweden2015In: Aquaculture International, ISSN 0967-6120, E-ISSN 1573-143X, Vol. 23, no 1, p. 359-368Article in journal (Other academic)
    Abstract [en]

    Although once popular prior to the last century, the aquaculture of crucian carp Carassius carassius (L. 1758) in Sweden gradually fell from favour. This is the first genetic comparison of crucian carp from historic man-made ponds in the Scandinavian Peninsula. The aim was to identify old populations without admixture and to compare the relationship of pond populations from different provinces in Sweden. In total, nine microsatellite loci from 234 individuals from 20 locations in varied parts of Sweden were analysed. The genetic distances of crucian carp populations indicated that the populations in the southernmost province of Sweden, Scania, shared a common history. A pond population in the province Småland also showed a common inheritance with this group. In the province Uppland, further north in Sweden, the population genetic distances suggested a much more complex history of crucian carp distributions in the ponds. The data showed that there are some ponds with potentially old populations without admixture, but also that several ponds might have been stocked with fish from many sources. © 2014 The Author(s).

  • 16.
    Jeffries, Daniel L
    et al.
    University of Hull, Hull, UK.
    Copp, Gordon H
    Bournemouth University, Poole, UK.
    Lawson Handley, Lori
    University of Hull, Hull, UK.
    Olsén, K. Håkan
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Sayer, Carl D
    University College London, London, UK.
    Hänfling, Bernd
    University of Hull, Hull, UK.
    Comparing RADseq and microsatellites to infer complex phylogeographic patterns, an empirical perspective in the Crucian carp, Carassius carassius, L2016In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 25, no 13, p. 2997-3018Article in journal (Refereed)
    Abstract [en]

    The conservation of threatened species must be underpinned by phylogeographic knowledge. This need is epitomised by the freshwater fish Carassius carassius, which is in decline across much of its European range. Restriction site associated DNA sequencing (RADseq) is increasingly used for such applications, however RADseq is expensive, and limitations on sample number must be weighed against the benefit of large numbers of markers. This trade-off has previously been examined using simulation studies, however, empirical comparisons between these markers, especially in a phylogeographic context, are lacking. Here, we compare the results from microsatellites and RADseq for the phylogeography of C. carassius to test whether it is more advantageous to genotype fewer markers (microsatellites) in many samples, or many markers (SNPs) in fewer samples. These datasets, along with data from the mitochondrial cytochrome b gene, agree on broad phylogeographic patterns; showing the existence of two previously unidentified C. carassius lineages in Europe; one found throughout northern and central-eastern European drainages, and a second almost exclusively confined to the Danubian catchment. These lineages have been isolated for approximately 2.15 M years, and should be considered separate conservation units. RADseq recovered finer population structure and stronger patterns of IBD than microsatellites, despite including only 17.6% of samples (38% of populations and 52% of samples per population). RADseq was also used along with Approximate Bayesian Computation to show that the postglacial colonisation routes of C. carassius differ from the general patterns of freshwater fish in Europe, likely as a result of their distinctive ecology.

  • 17.
    Kellner, Martin
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Porseryd, Tove
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Hallgren, S
    Uppsala University.
    Porsch-Hällström, Inger
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Hansen, S H
    University of Copenhagen, Denmark.
    Olsén, K Håkan
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Waterborne citalopram has anxiolytic effects and increases locomotor activity in the three-spine stickleback (Gasterosteus aculeatus)2016In: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 173, p. 19-28Article in journal (Refereed)
    Abstract [en]

    Citalopram is an antidepressant drug, which acts by inhibiting the re-uptake of serotonin from the synaptic cleft into the pre-synaptic nerve ending. It is one of the most common drugs used in treatment of depression, it is highly lipophilic and frequently found in sewage treatment plant effluents and surface waters around the world. Citalopram and other selective serotonin re-uptake inhibitors have, at concentrations that occur in nature, been shown to have behavioural as well as physiological effects on fish and other animals. This study is the result of several different experiments, intended to analyse different aspects of behavioural effects of chronic citalopram exposure in fish. Our model species the three-spine stickleback is common in the entire northern hemisphere and is considered to be a good environmental sentinel species. Female three-spine sticklebacks were exposed to 0, 1.5 and 15μg/l nominal concentrations of citalopram for 21 days and subjected to the novel tank (NT) diving test. In the NT test, the fish exposed to 1.5μg/l, but not the 15μg/l fish made a significantly higher number of transitions to the upper half and stayed there for significantly longer time than the fish exposed to 0μg/l. The 15μg/l group, however, displayed a significantly lower number of freeze bouts and a shorter total freezing time. The test for locomotor activity included in the NT test showed that fish treated with 1.5 and 15μg/l displayed a significantly higher swimming activity than control fish both 5-7 and 15-17min after the start of the experiment. In the next experiment we compared fish exposed to 1.5μg/l and 0.15μg/l to pure water controls with regard to shoaling intensity and found no effect of treatment. In the final experiment the propensity of fish treated with 1.5μg/l to approach an unknown object and aggressive behaviour was investigated using the Novel Object test and a mirror test, respectively. The exposed fish ventured close to the unknown object significantly more often and stayed there for significantly longer time than unexposed fish. The aggression test yielded no statistically significant effects. It is concluded that citalopram changes the behaviour of the three-spine stickleback in a way that is likely to have ecological consequences and that it must not be considered an environmentally safe pharmaceutical.

  • 18.
    Kellner, Martin
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Porseryd, Tove
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Porsch Hällström, Inger
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Borg, Bertil
    Stockholm university.
    Roufidou, Chrysoula
    Stockholm university.
    Olsén, K. Håkan
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Developmental exposure to the SSRI citalopram causes long-lasting behavioural effects in the three-spined stickleback (Gasterosteus aculeatus)2018In: Ecotoxicology, ISSN 0963-9292, E-ISSN 1573-3017, Vol. 27, no 1, p. 12-22Article in journal (Refereed)
    Abstract [en]

    Selective Serotonin Re-uptake Inhibitors (SSRIs) are a class of psychotropic drugs used to treat depression in both adolescents and pregnant or breast-feeding mothers as well as in the general population. Recent research on rodents points to persistent behavioural effects of pre- and perinatal exposure to SSRI which last into adulthood. To study effects of developmental exposure in fish, three-spine sticklebacks were exposed to 1.5 µg/l of the SSRI citalopram in the ambient water for 30 days, starting two days post-fertilisation. After 100 days of remediation in clean water the fish were put through an extensive test battery. Feeding behaviour was tested as the number of bites against a piece of food and found to be increased in the exposed fish. Aggression levels were measured as the number of bites against a mirror image during 10 minutes and was also found to be significantly increased in the exposed fish. Novel tank behaviour and locomotor activity was tested in an aquarium that had a horizontal line drawn half-way between the bottom and the surface. Neither the latency to the first transition to the upper half, nor the number of transitions or the total time spent in the upper half was affected by treatment. Locomotor activity was significantly reduced in the exposed fish. The light/dark preference was tested in an aquarium where the bottom and walls were black on one side and white on the other. The number of transitions to the white side was significantly reduced in the exposed fish but there was no effect on the latency to the first transition or the total time spent in the white half. The results in the current study indicate that developmental SSRI exposure causes persistent behavioural effects in fish and contribute to the existing knowledge about SSRIs as environmental pollutants.

  • 19.
    Kellner, Martin
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Porseryd, Tove
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Porsch-Hällström, Inger
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Hansen, Steen
    Univ. of Copenhagen.
    Olsén, K. Håkan
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Environmentally relevant concentrations of citalopram partially inhibit feeding in the three-spine stickleback (Gasterosteus aculeatus)2015In: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 158, p. 165-170Article in journal (Refereed)
    Abstract [en]

    Selective Serotonin Re-uptake Inhibitors (SSRI) are mood-altering, psychotropic drugs commonly used in the treatment of depression and other psychological illnesses. Many of them are poorly degraded in sewage treatment plants and enter the environment unaltered. In laboratory studies, they have been demonstrated to affect a wide range of behaviours in aquatic organisms. In this study we investigated the effect of a three-week exposure to 0.15 and 1.5 μg/l of the SSRI citalopram dissolved in the ambient water on the feeding behaviour in three-spine stickleback (Gasterosteus aculeatus). Feeding, measured as the number of attacks performed on a piece of frozen bloodworms during a 10-min period, was reduced by 30–40% in fish exposed to both 0.15 and 1.5 μg/l citalopram. The effects of the environmentally relevant concentration 0.15 μg/l on feeding, an important fitness characteristic, suggests that the ecological significance of environmental SSRI exposure may be pronounced.

  • 20.
    Kitambi, Satish Srinivas
    et al.
    Södertörn University, School of Life Sciences. Karolinska Institutet.
    Archer, Amena
    Karolinska Institutet.
    Hallgren, Stefan
    Södertörn University, School of Life Sciences.
    Olsén, K Håkan
    Södertörn University, School of Life Sciences.
    Gustafsson, Åke
    Karolinska Institutet.
    Mode, Agneta
    Karolinska Institutet.
    The role of liver X receptor (lxr) in the developing eyeManuscript (preprint) (Other academic)
  • 21. Moore, A
    et al.
    Olsén, K Håkan
    Södertörn University College, Avdelning Naturvetenskap.
    Lower, N
    Kindahl, Hans
    The role of F-series prostaglandins as reproductive priming pheromones in the brown trout2002In: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 60, no 3, p. 613-624Article in journal (Refereed)
    Abstract [en]

    Electrophysiological studies demonstrated that the olfactory epithelium of mature male brown trout Salmo trutta parr was acutely sensitive to F-series prostaglandins (PGFS) PGF(1alpha) and PGF(2alpha), with detection threshold concentrations of 10(-11) M. The olfactory epithelium was also sensitive to the PGF metabolite 15-ketoPGF(2alpha) (threshold 10(-8) M), but did not detect a further metabolite, 13,14,-dihydro-15-ketoPGF(2alpha). Immature brown trout did not detect any of the prostaglandins tested. Exposure of mature male brown trout parr to waterborne PGF(1alpha) and PGF(2alpha) (concentration 10(-8) M). resulted in significant increases in levels of expressible milt and the plasma concentrations of 17,20-betadihydroxy-4-pregnen-3-one, testosterone and 11-ketotestosterone. The olfactory epithelium of both immature and mature male brown trout parr was sensitive to the urine and ovarian fluid from ovulated female brown trout. Exposure of mature male brown trout parr to ovarian fluid resulted in an increase in the levels of plasma 17,20beta-dihydroxy-4-pregnen-3-one whilst exposure to urine increased the levels of expressible milt. In addition, PGF(2alpha) was found to be present within both the urine and ovarian fluid of mature female brown trout. It is suggested that the F-series prostaglandins have a role as priming pheromones in male brown trout.

  • 22.
    Nielsen, Sebastian V
    et al.
    Aarhus University, Aarhus, Denmark.
    Kellner, Martin
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Henriksen, Per G
    Aarhus University, Aarhus, Denmark.
    Olsén, Håkan
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Hansen, Steen H
    University of Copenhagen, Copenhagen, Denmark.
    Baatrup, Erik
    Aarhus University, Aarhus, Denmark.
    The psychoactive drug Escitalopram affects swimming behaviour and increases boldness in zebrafish (Danio rerio)2018In: Ecotoxicology, ISSN 0963-9292, E-ISSN 1573-3017, Vol. 27, no 4, p. 485-497Article in journal (Refereed)
    Abstract [en]

    was not significantly different from control fish in either sex. The results of this study demonstrate that Escitalopram can affect subtle but ecologically important aspects of fish behaviour and lends further credibility to the assumption that Escitalopram is an environmentally active pharmaceutical.

  • 23.
    Olsen, K Håkan
    et al.
    Södertörn University, Avdelning Naturvetenskap.
    Grahn, Mats
    Södertörn University, Avdelning Naturvetenskap.
    Lohm, Jakob
    Influence of MHC on sibling discrimination in Arctic char, Salvelinus alpinus (L.)2002In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 28, no 4, p. 783-795Article in journal (Refereed)
    Abstract [en]

    The preference of juvenile Arctic char [Salvelinus alpinus (L.)] for odors from siblings and nonsiblings with different major histocompability complex class II (MHC) genotypes was studied in two-choice fluviarium tests. In the first part of the study, test fish demonstrated no preference for water scented by a sibling with a MHC genotype different from its own versus water scented by a MHC identical nonsibling. When both donors were siblings with different MHC genotypes, however, the test fish chose the water scented by the fish with the same MHC type as the test fish. The results suggest that odors with information about kinship are dependent on MHC but also on other, unknown factors. In the second part of the study, we observed that fish isolated since fertilization did not show any behavioral discrimination towards siblings, based on MHC genotype. One reasonable explanation for this result is that Arctic char learn to discriminate between odors from individuals of different MHC types.

  • 24.
    Olsen, K Håkan
    et al.
    Södertörn University, Avdelning Naturvetenskap.
    Grahn, Mats
    Södertörn University, Avdelning Naturvetenskap.
    Lohm, Jakob
    The influence of dominance and diet on individual odours in MHC identical juvenile Arctic charr siblings2003In: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 63, no 4, p. 855-862Article in journal (Refereed)
    Abstract [en]

    No difference in attraction was observed in sibling Artic charr Salvelinus alpinus between water scented by dominant or subordinate major histocompability complex (MHC) identical fish observed in a two-choice fluviarium. In a second experiment, MHC identical sibling donors were given different types of food pellets before the preference test. The test fish showed a significant attraction to the sibling given the same kind of food as the test fish itself during the first 6 h of the fluviarium tests. The results suggest that diet has an influence on the odours released and can, in addition to MHC related odours, be used for information relating to group member identity.

  • 25.
    Olsén, Håkan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Effects of Pollutants on Olfactory Mediated Behaviors in Fish and Crustaceans2011In: Chemical communication in Crustaceans / [ed] Breithaupt and Thiel, New York: Springer, 2011, p. 507-529Chapter in book (Refereed)
  • 26.
    Olsén, K. Håkan
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Effects of pollutants on olfactory detection and responses to chemical cues including pheromones in fish2014In: Fish pheromones and related cues / [ed] Peter W. Sorensen and Brian D. Wisenden, Ames: Wiley-Blackwell, 2014, p. 217-236Chapter in book (Refereed)
  • 27.
    Olsén, K. Håkan
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Ask, Katarina
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Olsén, Hanna
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Porsch-Hällström, Inger
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Hallgren, Stefan
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Effects of the SSRI citalopram on behaviours connected to stress and reproduction in Endler guppy, Poecilia wingei 2014In: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 148, p. 113-121Article in journal (Refereed)
    Abstract [en]

    Psychoactive drugs, such as selective serotonin reuptake inhibitors (SSRI) have been identified in high levels in effluents from Swedish sewage treatment plants (STP) at concentrations high enough to give pharmacological effects in fish. In humans SSRIs are used in the treatment of depression and they have anxiolytic effects. In the present study we exposed Endler guppy (Poecilia wingei) of both sexes to citalopram that showed the highest concentrations of SSRIs in STP effluents and studied reproductive and non-reproductive behaviour. Male courting behaviours were not affected compared to control fish after 14-28 days exposure to 1μgL-1. In two experiments exposing both sexes to 0.2, 2.3 or 15μgL-1 for 21 days, fish exposed to the two highest doses showed anxiolytic effects when placed in a novel environment (novel tank diving test, NT). Males were only affected by exposure to 15μgL-1. They had significantly longer latency to explore the upper half of the aquarium, more visits and longer time spent in the upper half, and showed less bottom freezing behaviour, all markers of anxiolytic behaviour. In females exposure to 2.3 or 15μgL-1 significantly increased freezing behaviour, while no effects on other behaviour variables were observed. No effects on shoaling behaviour could be discerned. These results show that citalopram have anxiolytic effects on guppy fish and thus affect ecologically relevant behaviours of importance to survival of fish.

  • 28.
    Olsén, K Håkan
    et al.
    Södertörn University College, Avdelning Naturvetenskap.
    Bjerselius, Rickard
    Mayer, Ian
    Kindahl, Hans
    Both ovarian fluid and female urine increase sex steroid hormone levels in mature Atlantic salmon (Salmo salar) male parr2001In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 27, no 11, p. 2337-2349Article in journal (Refereed)
    Abstract [en]

    We compared the ability of urine and ovarian fluid from female Atlantic salmon (Salmo salar) to stimulate increase in plasma concentrations of sex steroid hormones in mature conspecific male parr (priming effect of the stimuli). We also tested the hypothesis that prostaglandin F-2 alpha (PGF(2 alpha)) may act as a priming pheromone in the tested stimulants. Individual males of salmon parr were exposed to female urine, ovarian fluid, urine-ovarian fluid mix, or PGF(2 alpha) Plasma concentrations of the sex steroids of 17,20 beta -dihydroxy-4-pregnen-3-one (17,20 beta -P) were higher in males exposed to urine, ovarian fluids, and PGF(2 alpha), compared to control males. PGF(2 alpha). and a mixture of urine and ovarian fluid also gave increased concentrations of 11-ketotestosterone (11-KT). Concentrations of PGF(2 alpha) were higher in ovarian fluids than in urine. A behavior test with mature male part in a fluviarium showed neither attraction to nor avoidance of 0.1 nM PGF(2 alpha), but plasma levels of 17,20 beta -P were significantly higher in exposed males compared to controls.

  • 29. Olsén, K Håkan
    et al.
    Bjerselius, Rickard
    Petersson, Erik
    Järvi, Torbjörn
    Mayer, Ian
    Hedenskog, Mikael
    Lack of species-specific primer effects of odours from female Atlantic salmon, Salmo salar, and brown trout, Salmo trutta2000In: Oikos, ISSN 0030-1299, E-ISSN 1600-0706, Vol. 88, no 1, p. 213-220Article in journal (Refereed)
    Abstract [en]

    We exposed, in two successive spawning seasons, individually placed precocious male Atlantic salmon (Salmo salar) and brown trout (Salmo trutta) parr to odour stimuli (ovarian fluid and urine mix) from ovulated conspecific or heterospecific anadromous females. Atlantic salmon parr had significantly higher plasma concentrations of the hormones 17 alpha,20 beta-dihydroxy-4-pregnen-3-one (17,20 beta-P), 11-ketotestosterone (11-KT) and testosterone (T) after exposure to odours from conspecific females or from brown trout females compared to parr exposed to a control solution (0.9% NaCl). We did not observe any significant differences between the hormone levels in salmon parr exposed to the two female odours. The salmon parr exposed to conspecific odours had significantly higher volumes of strippable milt compared to the controls, but we did not find any significant differences when comparing the effect of the two female odours. Brown trout parr had significantly higher plasma 17,20 beta-P levels following exposure to heterospecific female odours compared to control males, but there was no significant difference between males exposed to the different female odours. We did not observe any significant differences in plasma levels of T and 11-KT and in milt volumes between exposed and control trout. Taken together, the results from both tested species indicate that the potency of heterospecific stimuli in stimulating increased plasma sex steroid hormone levels in male parr was as strong as stimuli from conspecific females. The results are discussed in connection to observed hybridisation between the two sympatric species.

  • 30.
    Olsén, K Håkan
    et al.
    Södertörn University College, Avdelning Naturvetenskap.
    Johansson, Anna-Karin
    Bjerselius, Rickard
    Mayer, Ian
    Kindhal, Hans
    Mature Atlantic salmon (Salmo salar L.) male parr are attracted to ovulated female urine but not to ovarian fluid2002In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 28, no 1, p. 29-40Article in journal (Refereed)
    Abstract [en]

    The behavioral responses to urine and ovarian fluids from conspecific and heterospecific ovulated females were studied in mature Atlantic salmon (Salmo salar) male parr in a two-choice fluviarium. The males reacted differently to the stimulants. They spent more time in water scented by urine from salmon or brown trout (Salmo trutta L.) females compared to the time in water with ovarian fluids from salmon females. Furthermore, the males were attracted to salmon female urine (different from an indifferent reaction). Males exposed to urine of either species had higher plasma concentrations of testosterone (T) compared to unexposed controls. Measurement of the concentrations of prostaglandin F-2alpha (PGF(2alpha)) and its major metabolite 15-ketodihydroprostaglandin F-2alpha (15-ketodihydro-PGF(2alpha)) showed that the concentrations of the substances were higher in ovarian fluids of both species compared to those in urine. PGF(2alpha) showed a greater difference between ovarian fluid and urine than its major metabolite. The results suggest that urine of both species, in contrast to ovarian fluid, contain substances that attract mature Atlantic salmon male parr and that the active substances are neither PGF(2alpha) nor 15-keto-PGF(2alpha).

  • 31.
    Olsén, K. Håkan
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Lundh, T.
    SLU.
    Feeding stimulants in an omnivorous species, crucian carp Carassius carassius (Linnaeus 1758)2016In: Aquaculture Reports, ISSN 1015-4442, E-ISSN 1681-5726, Vol. 4, p. 66-73Article in journal (Refereed)
    Abstract [en]

    Many fish are during feeding dependent on both an olfactory and gustatory sense. Olfaction that acts as the distance sense induces arousal, food search behaviour and attraction to the source, followed by examination of food items by the gustatory sense. During buccal handling the fish decide if the feed will be rejected or swallowed. Amino acids are often stimulatory to the gustatory sense and can act as feeding stimulants. There are, however, inter-species differences concerning what kinds of amino acids act as feeding stimulants or deterrents. The species differences are probably dependent on the natural food choice. As feeding stimulating molecules increase feeding and growth, but deterrents have the reverse effect, it is important to know what kind of molecules have either effect. In the present study we record mouth handling time in the omnivorous crucian carp, Carassius carassius, of agar pellets containing water extracts of meal consisting of ordinary food pellets, blue mussels or a commercial carp attractant. These tests were followed by testing with agar pellets with synthetic amino acids, based on the content of the water extracts of the food pellets that was the only feeding stimulant. Neither extracts of mussel meal or of commercial carp attractants had a stimulating effect, i.e. no significant difference in handling time compared to agar pellets with only water. A mixture of five of the major amino acids in the food pellet extract (40 mM alanine, 20 mM glycine, 20 mM arginine, 8 mM serine, 8 mM leucin) gave a significant longer handling time compared to agar pellets with only water. The handling time was also longer for the three amino acids that had the highest concentrations (40 mM Ala, 20 mM Gly, 20 mM Arg) and finally with only alanine (128 mM). Agar pellets with only Ala gave, however, a significant shorter handling time compared to agar pellets with food pellet extract. The mussel meal extract had the same content of free amino acids and their ranking order was the same as in extracts of food pellets, but at much higher concentrations. Based on the free amino acid content, the mussel extract should have stimulated feeding. This indicates that the mussel extract contained compounds that acted as feeding deterrents in omnivorous crucian carp that do not feed on blue mussels in their natural environment. Previous studies have shown that blue mussel extracts act as feeding stimulants in several bottom feeding carnivorous fish. We finally tested betaine (100 mM) but the molecule had no significant stimulating effect that has been observed in some other fish species. © 2016 The Authors

  • 32.
    Olsén, K. Håkan
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Lundh, Torbjörn
    SLU.
    Feeding stimulants in an omnivorous species, crucian carp Carassius carassius (Linnaeus 1758)2017In: Chemical Senses, ISSN 0379-864X, E-ISSN 1464-3553, Vol. 42, no 2, p. E46-E47Article in journal (Other academic)
  • 33.
    Olsén, K Håkan
    et al.
    Uppsala University.
    Petersson, Erik
    Ragnarsson, Bjarne
    Lundqvist, Hans
    Järvi, Torbjörn
    Downstream migration in Atlantic salmon (Salmo salar) smolt sibling groups2004In: Canadian Journal of Fisheries and Aquatic Sciences, ISSN 0706-652X, E-ISSN 1205-7533, Vol. 61, no 3, p. 328-331Article in journal (Refereed)
    Abstract [en]

    Previous studies have shown kin recognition abilities in salmonid fish. Some authors have suggested that the attraction of juvenile fish to siblings may indicate preference for shoaling with kin. The aim of the present study is to test the prerequisite for the hypothesis that siblings swim spatially closer than unrelated fish during their seaward migration as smolts. Atlantic salmon (Salmo salar) eggs from three families were each reared in two tanks to create familiar and unfamiliar sibling smolts. Before the experiment started they were tagged individually withpassive integrated transponders (PITs). Twelve individuals from each of six groups were mixed and released together at several occasions in the upper end of the 400-m-long experimental stream. An automatic PIT-monitoring system placed in the outlet recorded the time for passage of each individual leaving the stream. Eighty-five percent of the juveniles monitored by the PIT antenna showed downstream migration at night hours and they migrated significantly more often closer in time to both known and unknown siblings than to unrelated fish. The results suggest that there is a genetic component in the migratory behaviour of Atlantic salmon smolts and support the hypothesis that smolts migrate in kin-structured groups.

  • 34.
    Olsén, K Håkan
    et al.
    Södertörn University, School of Life Sciences.
    Sawisky, G. R.
    Stacey, N. E.
    Endocrine and milt responses of male crucian carp (Carassius carassius L.) to periovulatory females under field conditions2006In: General and Comparative Endocrinology, ISSN 0016-6480, E-ISSN 1095-6840, Vol. 149, no 3, p. 294-302Article in journal (Refereed)
    Abstract [en]

    Laboratory studies in domesticated goldfish (Carassius auratus) show that, during the preovulatory luteinizing hormone (LH) surge, females release a complex steroidal pheromone that induces in males a rapid increase of plasma LH, which in turn increases strippable milt (sperm and seminal fluid) prior to ovulation and spawning. The objective of this study was to determine if the same phenomenon occurs in a wild congener, the crucian carp (Carassius carassius), under field conditions where fish are held in natural waters under ambient temperature and photoperiod. During the spawning season in June 2003, crucian carp were trapped in a small pond near Uppsala, Sweden, and held separately by sex in floating net pens. Addition of untreated females to male pens did not change male LH concentrations or milt volume during the 17 h sampling period. In contrast.. addition of females injected with Ovaprim (TM) (to induce an LH surge and ovulation) increased male LH concentrations at all sample times (5, 9, 13, and 17 h) following female addition and increased milt volumes at all but the first (5 h) sample time. Similar increases in male LH and milt that also occurred when untreated females ovulated spontaneously after addition to male pens suggest it is female ovulatory condition, rather than injection of ovaprim per se, that induced male LH and milt responses. Males also increased LH and milt 9 It after addition of females injected with the goldfish pheromonal steroid 4-pregnen-17,20 beta-diol-3-one (17,20 beta P), suggesting that similar responses to ovaprim-injected females were due, at least in part, to release of preovulatory pheromonal steroid(s). The clear and consistent effects of ovulatory females on male LH and milt, and the fact that crucian carp adapted well to confinement.. ovulated spontaneously, and exhibited apparently normal spawning behavior, all suggest that this species can serve as a useful cyprinid model to study reproductive processes in natural conditions.

  • 35.
    Olsén, K Håkan
    et al.
    Södertörn University College, School of Chemistry, Biology, Geography and Environmental Science.
    Stacey, N
    Crucian carp (Carassius carassius) male response toovulatory female in the wild2005In: List of Abstracts from the Sixteenth Annual Meeting of the European Chemoreception Research Organisation, 2005, p. -A54Conference paper (Other academic)
  • 36. Palm, Stefan
    et al.
    Dannewitz, Johan
    Järvi, Torbjörn
    Koljonen, Marja-Liisa
    Prestegaard, Tore
    Olsén, K Håkan
    Södertörn University, School of Life Sciences.
    No indications of Atlantic salmon (Salmo salar) shoaling with kin in the Baltic Sea2008In: Canadian Journal of Fisheries and Aquatic Sciences, ISSN 0706-652X, E-ISSN 1205-7533, Vol. 65, no 8, p. 1738-1748Article in journal (Refereed)
    Abstract [en]

    Several studies have shown that fish shoals may consist of closely related individuals. It has been found. for example, that released out-migrating salmon smolts tend to aggregate with kin. including when sibling groups have been reared separately. We used genetic microsatellite markers to test whether "shoals" of adult Atlantic salmon (Salmo salar) during the marine phase (i.e., aggregations of fish Caught in drift nets at offshore feeding areas in the Baltic Sea) consisted of closely related individuals (full-siblings, half-siblings). We found no evidence of kin cohesiveness related to shoals, however. Despite a weak overall tendency for individuals assigned to the same population (river or stock) to Occur tooether, estimates of genetic relatedness in combination with consistent heterozygote deficiencies. and results from mixed-stock analyses and assignment tests collectively indicated that shoals consisted of unrelated fish from multiple populations.

  • 37.
    Porseryd, Tove
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Kellner, Martin
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Reyhanian, Nasim
    Örebro University.
    Volkova, Kristina
    Örebro University.
    Elabbas, Lubna
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Ullah, Shahid
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies. Karolinska University Hospital Laboratory.
    Olsén, K. Håkan
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Dinnétz, Patrik
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Porsch Hällström, Inger
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Combinatory effects of low concentrations of 17α-etinylestradiol and citalopram on non-reproductive behavior in adult zebrafish (Danio rerio)2017In: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 193, p. 9-17Article in journal (Refereed)
    Abstract [en]

    Sewage treatment plant effluents contain a complex mixture of pharmaceuticals, personal care products and industrial chemicals, thus exposing aquatic organisms. Still, the consequences of exposure to combinations of different classes of drugs is largely unknown. In this study, we expose adult zebrafish (Danio rerio) males and females to low, environmentally relevant concentrations of the endocrine disrupting chemical 17α-ethinyl estradiol (EE2) and the selective serotonin re-uptake inhibitor (SSRI) citalopram, alone and in combination, and analyse three non-reproductive behaviours of importance for population fitness.

    Two weeks exposure to 0.1 and 0.5 ng/LEE2 resulted in increased anxiety in males in the scototaxis (light/dark preference) test. Significantly longer latency periods before entering the white zone and fewer visits in the white zone were observed in males exposed to both 0.1 and 0.5 ng/LEE2 compared to unexposed males. No significant effects of citalopram alone (0.1 and 0.5 µg/L) were observed in the scototaxis test. The combined exposures (0.1 ng/L EE2 + 0.1 µg/L citalopram and 0.5 ng/L EE2 + 0.5 µg/L citalopram) resulted in abolishment of the anxiogenic effects of EE2, with significantly shorter latency period (low dose) and more transitions to white (high and low dose) than in fish exposed to EE2 alone. No significant effects of either EE2, citalopramor the combination of the two were observed in females. In the novel tank test, significantly more transitions to the upper half of the tank were observed in males exposed to 0.1 µg/L citalopram alone compared to unexposed males while males exposed to 0.1 ng/lEE2 had significantly shorter latency period to enter the upper half. Exposure to the combination of the two low concentrations did, however, result in a significantly longer latency and fewer transitions to upper half compared to both control, EE2- and citalopram-exposed males. These males also spent significantly less time in the upper half than the fish exposed to 0.1 ng/l EE2 or 0.1 µg/l citalopram alone. No significant effects on novel tank behaviour were observed in females or males exposed to the higher concentrations. In the shoaling test, males exposed to 0.1 µg/L citalopram and females exposed to 0.5 ng/l EE2 made significantly fewer transitions away from peers while males exposed to 0.1 µg/L citalopram + 0.1 ng/l EE2 performed significantly more transitions than the fish exposed to 0.1 µg/L citalopram alone.

    In conclusion, this study shows that very low concentrations ofEE2, at or slightly above the predicted noeffect concentration (NOEC), affects anxiety in zebrafish males. Furthermore, citalopram, in spite of marginal effect of its own at such low levels, counteracts the response to EE2. This study represents an initial effort to understand the effects on water-living organisms of the cocktails of anthropogenic substances contaminating aquatic environments.

  • 38.
    Reyhanian, Nasim
    et al.
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Molecular biology.
    Volkova, Kristina
    Södertörn University, School of Life Sciences, Environmental science.
    Hallgren, Stefan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Bollner, Tomas
    Södertörn University, School of Life Sciences, Biology.
    Olsson, Per-Erik
    Olsén, K Håkan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Porsch Hällström, Inger
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Molecular biology.
    17α-Ethinyl estradiol affects anxiety and shoaling behavior in adult male zebra fish (Danio rerio)2011In: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 105, p. 41-48Article in journal (Refereed)
  • 39. Saglio, P
    et al.
    Bretaud, S
    Rivot, E
    Olsén, K Håkan
    Södertörn University, Avdelning Naturvetenskap.
    Chemobehavioral changes induced by short-term exposures to prochloraz, nicosulfuron, and carbofuran in goldfish2003In: Archives of Environmental Contamination and Toxicology, ISSN 0090-4341, E-ISSN 1432-0703, Vol. 45, no 4, p. 515-524Article in journal (Refereed)
    Abstract [en]

    The behavioral effects of short periods (2, 4, 6, 8 h) of static exposure to prochloraz (imidazole fungicide) and nicosulfuron (sulfonylurea herbicide) were recorded in goldfish (Carassius auratus). Observations were also made in an olfactometer to assess the effects of 8-h exposures to these two pesticides and to carbofuran (carbamate insecticide) on the behavioral responses to the flow of a solution of four L-amino acids (glycine, alanine, valine, taurine), mixed in the same relative proportions as in the urine of conspecifics. Each pesticide was tested at three sublethal concentrations (25, 50, 100 mug/L), and the behaviors recorded were related to swimming pattern, social interactions, and comfort movements. Static exposures to prochloraz affected horizontal displacements, burst swimming, grouping, and buccal movements. Static exposures to nicosulfuron affected burst swimming and grouping. In pesticide-unexposed fish (control), the flow of the amino acid solution induced attraction, decreased sheltering, and increased horizontal displacements, burst swimming, buccal movements, and antagonistic interactions. Compared to the controls, some of the behavioral responses to the solution of amino acids were significantly different after 8 It of subacute exposure to prochloraz and carbofuran. Both pesticides decreased attraction and increased sheltering. In addition, carbofuran decreased buccal movements and antagonistic interactions. Contrastingly, exposure to nicosulfuron showed no significant effect. This study further confirms the great vulnerability of fish behavior and chemocommunication processes to exposure to waterborne pesticides.

  • 40. Saglio, P
    et al.
    Olsén, K Håkan
    Bretaud, S
    Behavioral and olfactory responses to prochloraz, bentazone, and nicosulfuron-contaminated flows in goldfish2001In: Archives of Environmental Contamination and Toxicology, ISSN 0090-4341, E-ISSN 1432-0703, Vol. 41, no 2, p. 192-200Article in journal (Refereed)
    Abstract [en]

    The immediate behavioral responses of goldfish (Carassius auratus) to pesticide-contaminated flows were recorded in a countercurrent olfactometer. In addition, electro-olfactograms were recorded from the epithelial surface of the olfactory rosette as a preliminary check for the. olfactory sensitivity of the fish to the pesticides tested. All tests were run on prochloraz (imidazole fungicide), bentazone (diazine herbicide), and nicosulfuron (sulfonylurea herbicide). Behavioral effects were assessed, at four concentrations (10 mug/L, 100 mug/L, 1 mg/L, 10 mg/L), on endpoints related to swimming pattern (preference-avoidance responses, burst swimming reactions), comfort activities (buccal movements, feeding attempts), and social relations (antagonistic acts, grouping). The behavior of the fish appeared particularly sensitive to prochloraz exposure. As a whole, prochloraz-contaminated flows showed significant effects on the six behaviors studied; bentazone and nicosulfuron affected three and five, respectively. At the lowest concentration, prochloraz also showed more effects than the two other pesticides. Some of the behavioral endpoints. were found particularly sensitive to a given chemical. Pesticide-contaminated flows also induced significant changes in swimming orientation of the fish. Attraction was observed in response to flowing solutions of prochloraz (1 mg/L,10 mg/L), bentazone (10 mug/L, 10 mg/L), and nicosulfuron (I mg/L, 10 mg/L). At a concentration of 1 mg/L, none of the pesticides induced a noticeable depolarization of the olfactory epithelium, suggesting that these chemicals are not detected by the olfactory sense of the fish. These results are discussed in the light of the data concerning effects of pesticides on behavior and chemical communication in fish.

  • 41.
    Sommer, Christian
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Olsén, K. Håkan
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Sex odour preference in guppy (Poecilia wingei) males are influenced by the social environment2017In: Chemical Senses, ISSN 0379-864X, E-ISSN 1464-3553, Vol. 42, no 2, p. E47-E47Article in journal (Other academic)
  • 42.
    Sommer, Christian
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Olsén, K. Håkan
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Sex odour preference in guppy (Poecilia wingei) males is influenced by the social environment2016In: Behaviour, ISSN 0005-7959, E-ISSN 1568-539X, Vol. 153, no 12, p. 1419-1434Article in journal (Refereed)
    Abstract [en]

    The social environment of animals, particularly in the early stages of life, can have great impact on species-specific and sex-specific behaviours. These changes can be irreversible and continue during the entire life. In the present study we asked the question whether the social environment of male Endler's guppies, Poecilia wingei, housed in an all-male community could affect their preference response to female or male odour cues in a flow through Y-maze. After 30 days in an all-male group males were tested for their preference-avoidance responses to conspecific odours. The males were attracted to male-scented water but not to water scented by females. In simultaneous choice between male and female odours they demonstrated no significant preference. The males were attracted to male-scented water after they were kept for 48 h or 12 days with females. After the Y-maze tests the males' were placed with two females and their courting behaviour were recorded. The males showed low frequencies of reproductive behaviours. In the all-male group the males had been courting each other. The results show that the social environment influence sexual odour preference and courting behaviour in guppy males.

  • 43. Stacey, N. E.
    et al.
    Van der Kraak, G. J.
    Olsén, K. Håkan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Male primer endocrine responses to preovulatory female cyprinids under natural conditions in Sweden2012In: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 80, no 1, p. 147-165Article in journal (Refereed)
    Abstract [en]

    This study investigated two related aspects of male-female reproductive interactions in the family Cyprinidae: (1) whether ovulating female rudd Scardinius erythrophthalmus (subfamily Leuciscinae) induce endocrine and gonadal priming responses in conspecific males, a phenomenon which has been described only in species from the subfamily Cyprininae such as goldfish, Carassius auratus, crucian carp Carassius carassius and common carp, Cyprinus carpio and (2) whether the stimuli mediating these responses are species-specific. Field studies of three sympatric European cyprinids, two leuciscins (S. erythrophthalmus and white bream Blicca bjoerkna) and one cyprinin (C. carassius), were conducted on fishes captured in Sweden in the spawning season and held in net pens under natural conditions. As previously reported in C. carassius, male S. erythrophthalmus increased milt (sperm and seminal fluid) volume and plasma concentrations of the sperm maturation hormone 4-pregnen-17,20 beta-diol-3-one (17,20 beta-P) when they were held with female S. erythrophthalmus induced to ovulate by injection of Ovaprim (GnRH analogue plus dopamine antagonist). Male S. erythrophthalmus had larger milt volumes than male C. carassius prior to and following exposure to ovulatory conspecifics, but exhibited a smaller proportional milt increase in response to stimulation, suggesting species differences in sperm allocation at spawning. The presence of female S. erythrophthalmus and B. bjoerkna did not affect milt volumes of C. carassius under two experimental conditions: (1) ovulating S. erythrophthalmus and B. bjoerkna did not increase the milt volumes of C. carassius and (2) S. erythrophthalmus and B. bjoerkna did not interfere with the milt volume increase induced in male C. carassius by ovulating conspecifics. These results suggest that, as in C. auratus, C. carassius and C. carpio (subfamily Cyprininae), female S. erythrophthalmus (subfamily Leuciscinae) release a preovulatory pheromone that exerts priming effects on male hormones and sperm allocation. The findings also indicate that C. carassius discriminate between the reproductive odours of conspecifics and heterospecifics.

  • 44.
    Svanberg, Ingvar
    et al.
    Institutionen för rysslandsstudier Uppsala universitet.
    Bonow, Madeleine
    Södertörn University, School of Life Sciences, Geography.
    Olsén, Håkan
    Södertörn University, School of Life Sciences, Biology.
    Fish ponds in Scania, and Linnaeus's attempt to promote aquaculture in Sweden2012In: Svenska Linnésällskapets årsskrift, ISSN 0375-2038, p. 85-100Article in journal (Other academic)
  • 45.
    Volkova, Kristina
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology. Örebro University.
    Reyhanian Caspillo, Nasim
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology. Örebro university.
    Porseryd, Tove
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Hallgren, Stefan
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies. Uppsala university.
    Dinnetz, Patrik
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Olsén, Håkan
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Porsch Hällström, Inger
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Transgenerational effects of 17α-Ethinyl Estradiol on anxiety behavior in the guppy, Poecilia reticulata2015In: General and Comparative Endocrinology, ISSN 0016-6480, E-ISSN 1095-6840, Vol. 223, p. 66-72Article in journal (Refereed)
  • 46.
    Volkova, Kristina
    et al.
    Södertörn University, School of Life Sciences, Environmental science.
    Reyhanian, Nasim
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Molecular biology.
    Kot-Wasik, Agata
    Gdańsk University of Technology.
    Olsén, Håkan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Porsch-Hällström, Inger
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Molecular biology.
    Hallgren, Stefan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Brain circuit imprints of developmental 17α-ethinylestradiol exposure in guppies (Poecilia reticulata): Persistent effects on anxiety but not on reproductive behaviour2012In: General and Comparative Endocrinology, ISSN 0016-6480, E-ISSN 1095-6840, Vol. 178, no 2, p. 282-290Article in journal (Refereed)
    Abstract [en]

    The effects of endocrine disruptors may vary with the timing of exposure. The physiological implications of adult exposure are present during and shortly after exposure while embryonic exposure can imprint changes manifested in adulthood. In this study, guppy (Poecilia reticulata) embryos were exposed to 2 ng/L and 20 ng/L of 17α-ethinylestradiol during development via the mother and reared in clean water from gestation until 6 months of age. As adults, fish exposed to 20ng/L during development showed significantly altered behaviour in the Novel Tank test, where anxiety is determined as the tendency to remain at the bottom upon introduction into an unfamiliar tank. 17α-ethinylestradiol treatment increased the latency time before swimming to the upper half of the tank and decreased the number of transitions to the upper half. In control females the basal stress behaviour responses were significantly higher than in males, as indicated by longer latency period and fewer and shorter visits to the upper half, supporting the importance of gonadal hormones for the behaviour. The anxiety increased, however, with treatment in both sexes, suggesting that the observed response is not entirely due to feminization of the males. Shoaling behaviour, analyzed as tendency to leave a shoal of littermates, was neither sex-differentiated nor changed by treatment. Also male reproductive behaviour, brain aromatase activity and testes histology, previously shown to respond to oestrogen exposure in adult guppy, were unaffected by the developmental treatment. This suggests that the stress system in the guppy is very sensitive to 17α-ethinylestradiol, which possibly causes an early organisational imprint on the brain circuit that regulates stress reactions.

  • 47.
    Wouters, Johanna
    et al.
    Södertörn University, School of Life Sciences, Environmental science.
    Janson, Sven
    Södertörn University, School of Life Sciences, Environmental science.
    Luskova, Vera
    Olsén, K. Håkan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Molecular identification of hybrids of the invasive gibel carp Carassius auratus gibelio and crucian carp Carassius carassius in Swedish waters2012In: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 80, no 7, p. 2595-2604Article in journal (Refereed)
    Abstract [en]

    Both mitochondrial DNA sequence and two nuclear microsatellite markers were used to confirm the identity of the first record of Carassius auratus gibelio in the western (Swedish) Baltic Sea region. A total of 49 fishes were analysed, where 22 were from three Swedish sites connected to the Baltic Sea. The D-loop mitochondrial DNA sequences showed that 16 of 22 Swedish fishes were related to C. a. gibelio. The phylogenetic analysis of these sequences showed that these fish are probably not native, but represent different lineages of C. a. gibelio from China, Japan and Russia. All except three of these 16 fishes had microsatellite alleles suggesting hybridization with Carassius carassius. These findings suggest that a cryptic invasion of C. a. gibelio might be in progress.

  • 48.
    Wouters, Johanna
    et al.
    Södertörn University, School of Life Sciences, Environmental science.
    Janson, Sven
    Södertörn University, School of Life Sciences, Environmental science.
    Olsén, K. Håkan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Why didn’t we notice them earlier? The invasive fish Carassius gibelio(gibel carp) identified by genetic methods in Swedish waters.2011In: 7th International Conference on Marine Bioinvasions: Abstract Book, 2011, p. 162-Conference paper (Other academic)
1 - 48 of 48
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