| observations on the life-cycle of the strigeoid trematode, apatemon (apatemon) gracilis (rudolphi, 1819) szidat, 1928. | the life-cycle of apatemon (a.) gracilis was completed in the laboratory. the snail host is lymnaea peregra (muller). the cercaria is redescribed from a wide range of material. metacercariae were found in naturally infected rainbow trout (salmo gairdneri richardson), three-spined sticklebacks (gasterosteus aculeatus l.) and stone loach (nemacheilus barbatulus (l.)) from scotland and in three-spined sticklebacks from iceland. in trout, most metacercariae were found in the pericardial cavity, in s ... | 1976 | 965706 |
| life cycle and structure of the fish digenean brachyphallus crenatus (hemiuridae). | cystophorous cercariae from retusa obtusa (montagu) (gastropoda, opisthobranchia, retusidae) develop into adults of brachyphallus crenatus (rudolphi, 1802) odhner, 1905 (hemiuridae). the free-swimming cercariae were ingested by laboratory-reared acartia tonsa dana, and the cercarial body was injected into the hemocoel of the copepod. two-week-old metacercariae held at 15 c were infective to stickleback gasterosteus aculeatus linnaeus. the cercariae of b. crenatus are very similar to the cercaria ... | 1992 | 1556648 |
| segregation and co-occurrence of larval cestodes in freshwater fishes in the bothnian bay, finland. | two autogenic (triaenophorus crassus and t. nodulosus) and four allogenic (diphyllobothrium latum, d. dendriticum, d. ditremum and schistocephalus solidus) larval cestode species were found in 13 out of 31 fish species studied from the bothnian bay, ne baltic. gasterosteus aculeatus was the most heavily infected fish with 4 larval cestode species; for two of them (d. ditremum and s. solidus) the three-spined stickleback was found to be the required fish intermediate host. among allogenic cestode ... | 1992 | 1614732 |
| 3,4-dihydroxyphenylethylamine, l-3,4-dihydroxyphenylalanine and 3,4,5-trihydroxyphenylalanine: oxidation and binding to membranes. a comparative study of a neurotransmitter, a precursor and a neurotransmitter candidate in primitive nervous systems. | at neutral (7.0) and slightly basic (8.2) ph, l-3,4-dihydroxyphenylalanine (l-dopa), 3,4,5-trihydroxyphenylalanine (5-oh-dopa) and 3,4-dihydroxyphenylethylamine (dopamine) undergo autoxidation. the binding of radiolabeled oxidation products of l-dopa, 5-oh-dopa and dopamine to membrane proteins was compared by a filtration procedure. membranes from tentacles of the sea anemone metridium senile bind significantly more 5-oh-dopa than l-dopa and dopamine. membranes from rat brain and brains from th ... | 1990 | 1973046 |
| transmission electron microscopic studies on the effects of toltrazuril on glugea anomala, moniez, 1887 (microsporidia) infecting the three-spined stickleback gasterosteus aculeatus. | a symmetric triazinone, toltrazuril, was tested in vivo against glugea anomala parasitizing the connective tissue of sticklebacks (gasterosteus aculeatus). naturally infected sticklebacks were incubated in toltrazuril-containing water as intermittent therapy (3 x 2 micrograms/ml for 6 h at 3-day intervals or 3 x 2 micrograms/ml for 24 h at 2-day intervals). as seen at the ultrastructural level, the drug caused severe damage to all developmental stages of g. anomala. when treatment was carried ou ... | 1990 | 2251246 |
| the life cycle of pygidiopsis ardeae køie, 1990 (digenea, heterophyidae). | ocellate cercariae, consistent with the description of cercaria angularis honer, 1961, developing in rediae in hydrobia ulvae (pennant) and hydrobia ventrosa (montagu) (prosobranchia, hydrobiidae) from denmark, were shown to be larvae of pygidiopsis ardeae køie, 1990 (heterophyidae, pygidiopsinae). euryhaline fishes such as the sticklebacks gasterosteus aculeatus linnaeus and pungitius pungitius (linnaeus), and the common goby pomatoschistus microps (krøyer) are second intermediate hosts in dani ... | 1990 | 2380862 |
| evidence for post-cyclic transmission in the life-history of neoechinorhynchus rutili (acanthocephala). | field observations at one site on brown trout (salmo trutta) and three-spined sticklebacks (gasterosteus aculeatus) concurrently infected with mature neoechinorhynchus rutili, together with the knowledge that large trout can be piscivorous in habit led to the proposition that the post-cyclic transmission of n. rutili may occur between these fish species. this route of transmission has been suggested for a number of acanthocephalan species. a laboratory experiment was conducted and it was demonst ... | 1988 | 3200606 |
| [coccidia of the stickleback gasterosteus aculeatus (l.)]. | | 1988 | 3388867 |
| distribution of noradrenaline in the brain of the teleost gasterosteus aculeatus l.: an immunohistochemical analysis. | the distribution of noradrenergic neurons in the brain of the three-spined stickleback was demonstrated with the indirect peroxidase-antiperoxidase (pap) immunohistochemical method with antibodies against a noradrenaline-bovine serum albumin conjugate. noradrenergic neuronal somata were exclusively located in the isthmal area of the brain stem and in the lower medulla. noradrenergic varicose axons innervate the reticular formation, motor nuclei, and interpeduncular nucleus of the brain stem, the ... | 1986 | 3540043 |
| treatment of fish parasites. 2. effects of praziquantel, niclosamide, levamisole-hcl, and metrifonate on monogenea (gyrodactylus aculeati, diplozoon paradoxum). | in research for successful treatment of fish parasitized by monogeneans, four substances (praziquantel, niclosamide, levamisole-hcl, and metrifonate) were tested in vivo against gyrodactylus aculeati parasitizing the skin of sticklebacks (gasterosteus aculeatus). fish were incubated in water containing different solutions of the drugs. praziquantel, niclosamide and levamisole-hcl were effective against gyrodactylus aculeati. praziquantel caused irreversible lesions in the parasite tegument (begi ... | 1987 | 3615395 |
| anterograde and retrograde filling of central neuronal systems with horseradish peroxidase under in vitro conditions. | in this study, a simple technique for neuronal tracing with horseradish peroxidase (hrp) in vitro is described. it can be applied to excised small brains of poikilothermic vertebrates, or to trimmed blocks or slices of brain tissue from homoiothermic vertebrates. the filling technique relies on the diffusion of hrp into transected axons of supravital neurons, and gives a golgi-like staining of the filled neuronal profiles. the incubation is carried out at 4 degrees c, which minimizes unspecific ... | 1985 | 3903362 |
| proceedings: apiosoma pisicola blanchard, 1885, and epistylis lwoffi fauré-fremiet, 1943 (protozoa: peritrichida) on three-spined stickleback, gasterosteus aculeatus l., in wales. | | 1974 | 4213808 |
| gyrodactylus alexanderi: reproduction, mortality, and effect on its host gasterosteus aculeatus. | | 1974 | 4451900 |
| immunocytological localization and identification of the msh-producing cells in the pituitary of the stickleback (gasterosteus aculeatus l.). | | 1974 | 4613602 |
| a quantitative approach to the effects of the plerocercoid of schistocephalus solidus müller 1776 on the ovarian maturation of the three-spined stickleback gasterosteus aculeatus l. | | 1974 | 4850273 |
| infections of the three-spined stickleback, gasterosteus aculeatus l., with the plerocercoid larvae of schistocephalus solidus (müller, 1776), with special reference to pathological effects. | | 1967 | 6067969 |
| the effects of joint stress on sticklebacks. | the effects on the three-spined stickleback, (gasterosteus aculeatus l.), of various combinations of stresses due to parasitism by schistocephalus solidus, dietary restriction, and exposure to cadmium (0.032 mg 1-1) were investigated. sticklebacks exposed to a combination of all three stressors died first with a median period of survival significantly shorter than that for fish subjected to fewer stressors. compared with fish on a restricted diet alone, parasitism plus dietary restriction also r ... | 1980 | 6893099 |
| the tapeworm schistocephalus solidus alters the activity and response, but not the predation susceptibility of infected copepods. | cyclops abyssorum and cyclops scutifer were experimentally infected with procercoids of the cestode schistocephalus solidus, then examined for altered behavior and susceptibility to predation, respectively. infected c. abyssorum differed from uninfected controls in their initial response to disturbance and their degree of activity but only when they harbored procercoids that were potentially infective to the next host. to examine the possible consequence of the altered behavior for susceptibilit ... | 1995 | 7707222 |
| [anisakis simplex (larva iii stage) in stickleback gasterosteus aculeatus from the southern baltic region]. | one specimen of iii larval stage of anisakis simplex was found in body cavity of female stickleback gasterosteus aculeatus caught in southern baltic, in kołobrzeg. in stickleback from baltic sea a. simplex was noted for the first time. it usually occurs in many other species of fish. | 1994 | 7801645 |
| goussia aculeati from the three-spined stickleback (gasterosteus aculeatus): field observations and ultrastructural features. | goussia aculeati, a parasite of intestinal epithelial cells of the three-spined stickleback (gasterosteus aculeatus) was found in 418 (47%) of 891 sticklebacks examined. the fish were obtained from 7 localities of waters in a natural resort area in north-west germany. g. aculeati mainly infected juvenile fish (312 (53%) of 590 examined). during a 2-years observation period no impact of season on the infection rate was obvious. ultrastructural studies on merogonic, gamogonic, and sporogonic devel ... | 1994 | 8087158 |
| mercury concentration of stickleback gasterosteus aculeatus from the gulf of gdańsk. | | 1993 | 8241627 |
| microvascularization of corpuscles of stannius in teleost fishes. | blood supply and microvascular patterns of stannius corpuscles were studied by scanning electron microscopy of vascular corrosion casts in the teleost fishes blennius pavo, zosterisessor ophiocephalus, and gasterosteus aculeatus. microvascular casts demonstrated that stannius corpuscles--depending on their location--have an arterial supply derived either directly from the dorsal aorta, from the trunk of the first ventral segmental artery of the tail, or from a renal artery. supplying arteries fo ... | 1995 | 8580505 |
| the toxicity of organoarsenic-based warfare agents: in vitro and in vivo studies. | the four arsenic-containing chemical warfare agents (cwa) adamsite (technical, 10-chloro-9-10-dihydrophenarsazine), clark 1 (diphenyl arsine chloride), clark 2 (diphenyl arsine cyanide), and lewisite (2-chloro-ethenyl dichloro arsine) were evaluated toxicologically using an in vitro and an in vivo model. the cwa were tested in vitro, using human leucocytes, in order to evaluate their effects on cell proliferation and cell cycle kinetics assayed by flow cytometry. the concentration for total inhi ... | 1996 | 8593082 |
| effects of an asymmetric triazine derivative, hoe 092 v, on glugea anomala, moniez, 1887 (microsporidia) parasitic in the three-spined stickleback gasterosteus aculeatus. | an asymmetric triazine derivative, hoe 092 v,2-[3,5-alpha-dichloro-4-(4-methyl-sulfonylphenoxy)-phenyl]- 1-methyl-hexahydro-1,2,4-triazine-3,5-dion, was tested in vivo against glugea anomala parasitizing the connective tissue of sticklebacks (gasterosteus aculeatus). naturally infected sticklebacks were incubated in 10-1 plastic aquaria in water containing 0, 2.5, 5, and 10 micrograms hoe 092 v/ml for 2, 3, and 4 h at 22 degrees c. as seen at the ultrastructural level, the drug caused severe dam ... | 1996 | 8801554 |
| treatment of fish parasites. 11. effects of different benzimidazole derivatives (albendazole, mebendazole, fenbendazole) on glugea anomala, moniez, 1887 (microsporidia): ultrastructural aspects and efficacy studies. | three different benzimidazole derivatives, albendazole [methyl-5-(propylthio)-2-benzimidazolcarbamate], mebendazole (methyl-5-benzoyl-2-benzimidazolcarbamatic acid methyl ester), and fenbendazole [methyl-5-(phenylthio)-2-benzimidazolcarbamate] were tested in vivo against glugea anomala parasitizing the connective tissue of sticklebacks (gasterosteus aculeatus). naturally infected sticklebacks were incubated in aerated plastic aquaria (10 1) at 22 degrees c in water containing 0, 1, 5, 10, or 50 ... | 1998 | 9491425 |
| ecological and genetic evidence for clonal reproduction in gyrodactylus gasterostei glaser, 1974. | reproduction of isolated gyrodactylus gasterostei from the three-spined stickleback, gasterosteus aculeatus, has been investigated. three lineages of isolated parasites, without opportunity for cross- or self-fertilisation, continued to reproduce for up to 19 generations (224 births) until experiments were discontinued. most parasites gave birth to two daughters only, although four individuals in one lineage gave birth three times. after the final birth the empty uterus expanded, while a large o ... | 1998 | 9801918 |
| use of protozoan communities for pollution monitoring. | a gradient of chronic organic pollution was identified in a small river in south-east england. the parasite fauna of the ubiquitous three-spined stickleback (gasterosteus aculeatus l.) was studied at the extremes of the pollution gradient and trichodinid ciliates identified as a potential bioindicator. a simple technique was developed for the quantification of whole body-burdens of trichodinids on small fish. three species of trichodinids were identified: trichodina domerguei, t. tenuidens and t ... | 1997 | 9802068 |
| ectoparasitic species of the genus trichodina (ciliophora: peritrichida) parasitising british freshwater fish. | seven species of the genus trichodina ehrenberg, 1838 were identified during a sampling programme of twenty freshwater fish species from approximately sixty sites in scotland, england and wales. species found include: trichodina acuta lom, 1961 from cyprinus carpio l., carassius auratus l., oncorhynchus mykiss (walbaum), salmo trutta l. and phoxinus phoxinus l.; trichodina domerguei wallengren, 1897 from gasterosteus aculeatus l.; trichodina tenuidens faure-fremiet, 1944 from gasterosteus aculea ... | 1998 | 9805782 |
| temporal prey distribution affects the competitive ability of parasitized sticklebacks. | parasitized animals are often reported to have a reduced competitive ability in experimental studies designed to examine foraging success under a specific type of competitive interaction; however, since animals compete under a range of competition regimes in natural situations, and because success is likely to require different foraging skills under each, it is unclear whether infected animals should be equally poor competitors under all competitive scenarios. we studied the foraging success of ... | 1998 | 9933545 |
| parasite communities of the salzhaff (northwest mecklenburg, baltic sea). i. structure and dynamics of communities of littoral fish, especially small-sized fish. | the parasites of ten fish species, including four gobiidae, three gasterosteidae, two syngnathidae, and one zoarcidae from the salzhaff region, northwest mecklenburg, baltic sea, were investigated in 1995 and 1996. as many as 36 parasite species, represented by diverse groups of helminths and protozoans as well as annelids and copepods, are found during 4 seasons in these hosts. by far the most abundant group is represented by digeneans, comprising 15 species, followed by 7 cestodans and 6 nemat ... | 1999 | 10227054 |
| axial variation in the threespine stickleback: relationship to hox gene expression. | despite mounting evidence that key developmental regulator genes are involved in significant macroevolutionary changes, there have been few studies demonstrating the functional significance of variation in such genes for the generation of population-level variation. in this study we examined and compared the expression domains of three hox gene homeobox sequences in embryos derived from two morphologically distinct populations of the threespine stickleback, gasterosteus aculeatus. we found withi ... | 1999 | 10415324 |
| host-dependent and seasonal variation in opisthaptoral hard parts of gyrodactylus cf. arcuatus from three pomatoschistus spp. and g. arcuatus from gasterosteus aculeatus: a multivariate approach. | gyrodactylus arcuatus-like monogeneans collected from the gills of 3 goby species, pomatoschistus minutus, p. lozanoi and p. pictus, from the voordelta area (sw netherlands) were compared on a morphometric basis with g. arcuatus from its type host, the three-spined stickleback, gasterosteus aculeatus. univariate and multivariate analysis was carried out on measurements of 17 characters of the opisthaptoral hard parts of 268 specimens. the contribution of host-dependent and seasonal factors to th ... | 1999 | 10446702 |
| parasite-associated growth enhancement in a fish-cestode system. | parasites impose an energetic cost upon their hosts, yet, paradoxically instances have been reported in which infection is associated with enhanced, rather than diminished, host growth rates. field studies of these parasite effects are problematic, since the pre-infection condition of the hosts is generally unknown. here, we describe a laboratory experiment in which the growth rate and body condition of 76 laboratory-reared three-spined stickleback fishes were examined before, during and after e ... | 2000 | 10821609 |
| the nuclear rdna region of gyrodactylus arcuatus and g. branchicus (monogenea: gyrodactylidae). | the primary structure of the ribosomal dna internal transcribed spacers (its-1 and its-2) and 5.8s rrna gene were used to characterize and identify 2 monogenean species of gyrodacrylus living externally on the threespine stickleback (gasterosteus aculeatus). the its region was amplified by pcr from freshwater, brackish, and marine isolates of gyrodactylus arcuatus and g. branchicus, and the ends of the coding regions were identified by comparative alignment. no intraspecific and very low intersp ... | 2000 | 11191921 |
| experimental infections of copepods and sticklebacks gasterosteus aculeatus with small ensheathed and large third-stage larvae of anisakis simplex (nematoda, ascaridoidea, anisakidae). | free-swimming ensheathed larvae of anisakis simplex were shown experimentally to be ingested by the copepods oitona similis and acartia tonsa and by the nauplii of barnacles balanus sp. the larvae did not grow in the copepod hemocoel. experimental infections of various malacostracans were unsuccessful. sticklebacks gasterosteus aculeatus are naturally infected with larvae of a. simplex in coastal brackish water. such sticklebacks may have acquired the infection by eating either a crustacean host ... | 2001 | 11199846 |
| no effect of a parasite on reproduction in stickleback males: a laboratory artefact? | experiments are often carried out in the laboratory under artificial conditions. although this can control for confounding factors, it may eliminate important factors that under natural conditions mediate the interaction under investigation. here, we show that different results can be gained in the field and in the laboratory regarding host-parasite interaction. in the field, courting three-spined stickleback males, gasterosteus aculeatus, were less often infected with plerocercoids of a cestode ... | 2001 | 11315179 |
| effects of schistocephalus solidus infection on brain monoaminergic activity in female three-spined sticklebacks gasterosteus aculeatus. | the three-spined stickleback gasterosteus aculeatus is an intermediate host of the tapeworm schistocephalus solidus. changes in predator avoidance, foraging and shoaling behaviour have been reported in sticklebacks infested with s. solidus, but the mechanisms underlying parasite-induced behavioural changes are not understood. monoamine neurotransmitters are involved in the control of behaviour and central monoaminergic systems are sensitive to various stressors. thus, the behavioural effects of ... | 2001 | 11429142 |
| effects of bis(tributyltin)oxide on antipredator behavior in threespine stickleback gasterosteus aculeatus l. | antipredator behavior was used as a parameter to detect effects caused by exposure to the organotin compound bis(tributyltin)oxide (tbto). three groups of threespine sticklebacks (gasterosteus aculeatus l.) were exposed to 3, 9 and 27 ppb tbto, respectively. a fourth control group was given the same treatment as the other three groups, but no tbto. antipredator behavior of the fish was evoked using a dummy heron (ardea cinerea) bill. tbto exposure caused significant changes in the spatial positi ... | 2001 | 11459153 |
| rapid genetic divergence in postglacial populations of threespine stickleback (gasterosteus aculeatus): the role of habitat type, drainage and geographical proximity. | the goal of this study was to evaluate the role of common ancestry, and of geographical or reproductive isolation, in genetic divergence in populations of threespine sticklebacks (gasterosteus aculeatus). using seven dna microsatellite loci we compared the effects of habitat type, drainage system and geographical proximity on genetic distance among 16 populations situated in an area in schleswig-holstein (germany) that became deglaciated approximately 12 000 years ago. stickleback population str ... | 2001 | 11703651 |
| chlorinated cyclodiene pesticide residues in blue mussel, crab, and fish in the gulf of gdańsk, baltic sea. | chlordane components (chls) and their metabolites (heptachlor, cis-heptachlor epoxide, u82, mc4, trans-chlordane, mc5, cis-chlordane, mc7, oxychlordane, mc6- and trans- and cis-nonachlor) and aldrin, dieldrin, endrin, isodrin, endosulfan 1, endosulfan 2, and mirex were quantified in the soft tissues of blue mussel, a whole crab, and whole fishes collected from the spatially different sites in the gulf of gdańsk. six to twelve chlordane compounds and metabolites and dieldrin were detected in all ... | 2001 | 11718327 |
| toxicity of methyl tert-butyl ether to marine organisms: ambient water quality criteria calculation. | in response to increasing concerns over the detection of methyl tert-butyl ether (mtbe) in groundwater and surface water and its potential effects in aquatic ecosystems, industry and the united states environmental protection agency (usepa) began to collaborate in 1997 to develop aquatic toxicity databases sufficient to derive ambient water quality criteria for mtbe consistent with usepa requirements. acute toxicity data for seven marine species, chronic toxicity data for an invertebrate, and pl ... | 2002 | 11996128 |
| the "crowding effect" in the cestode schistocephalus solidus: density-dependent effects on plerocercoid size and infectivity. | the occurrence of the crowding effect was demonstrated in plerocercoids of the cestode schistocephalus solidus infecting threespine stickleback gasterosteus aculeatus from walby and scout lakes, alaska. contrary to an earlier report, relatively large numbers of parasites (>3-4 plerocercoids) were observed to grow large enough in an intermediate host fish to become competent to infect and to mature in the definitive host under any of 3 assumed threshold values and 1 scenario of graded sizes for p ... | 2002 | 12054002 |
| parasite populations and communities from the shallow littoral of the orther bight (fehmarn, sw baltic sea). | parasites of host guilds, such as mud snails (five species), benthic crustaceans (six species) and small-sized fishes ( pomatoschistus microps, gasterosteus aculeatus, pungitius pungitius, young pleuronectes flesus), were investigated in the other bight off west fehmarn (kiel bight, german baltic sea). the hosts, especially the herbivorous hydrobia spp, gammarus spp and idothea chelipes, attained extremely high densities in three habitats ( enteromorpha belt, fucus belt, sandy bottom), which may ... | 2002 | 12122431 |
| altered host behaviour: manipulation or energy depletion in tapeworm-infected copepods? | parasites are able to influence intermediate hosts in a way that optimizes their growth and transmission to the next host. macrocyclops albidus (copepoda) suffer from a reduced escaping ability and an increased level of general activity, when infected with schistocephalus solidus (cestoda). this facilitates predation by the subsequent host, the three-spined stickleback. however, instead of adaptive host manipulation by the tapeworm, the altered copepod behaviour might be explained more simply as ... | 2002 | 12211611 |
| intersex in feral marine and freshwater fish from northeastern germany. | a histopathological assessment of the gonad of male fish was performed as part of biological field studies carried out in coastal waters and small rivers in mecklenburg-western pomerania, northeastern germany. in the marine environment the eelpout (zoarces viviparus) was selected as sentinel species. the three spined stickleback (gasterosteus aculeatus) and perch (perca fluviatilis) were chosen at freshwater locations. histopathology of the testis revealed the presence of intersexuality in speci ... | 2002 | 12408630 |
| outcrossing increases infection success and competitive ability: experimental evidence from a hermaphrodite parasite. | the maintenance of two genetically distinct reproductive modes such as outcrossing and selfing within a population of animals or plants is still a matter of considerable debate. hermaphroditic parasites often reproduce either alone by selfing or in pairs by outcrossing. they can be used as a model to study potential benefits of outcrossing. any advantage from outcrossing may be important, especially in host-parasite coevolution, but has not, to our knowledge, been studied yet in any parasite spe ... | 2002 | 12487354 |
| temporal variation in divergent selection on spine number in threespine stickleback. | short-term temporal cycles in ecological pressures, such as shifts in predation regime, are widespread in nature yet estimates of temporal variation in the direction and intensity of natural selection are few. previous work on threespine stickleback (gasterosteus aculeatus) has revealed that dorsal and pelvic spines are a defense against gape-limited predators but may be detrimental against grappling insect predators. in this study, we examined a 15-year database from an endemic population of th ... | 2002 | 12583587 |
| genetic relationships and origin of two geographic groups of the freshwater threespine stickleback, 'hariyo'. | 'hariyo' comprise the southernmost freshwater populations of the threespine stickleback, gasterosteus aculeatus species complex, distributed in central honshu, japan. two geographic groups (gifu and shiga) of the 'hariyo' have been recognized as differing from each other in some morphological and ecological features. in order to elucidate the genetic characteristics and phylogenetic position of these populations, partial sequences of the mitochondrial cytochrome b gene were compared in 123 speci ... | 2003 | 12655188 |
| reduction of egg size in natural populations of threespine stickleback infected with a cestode macroparasite. | manifestations of infectious disease may represent host adaptations to avoid or reduce the effects of infection on host fitness, parasite manipulations that benefit the pathogen's fitness, or nonadaptive side effects of parasitism. threespine stickleback fish (gasterosteus aculeatus) from alaska and the cestode macroparasite schistocephalus solidus provide an excellent system for study of the effects of parasitism on host egg size because females in populations there are capable of producing clu ... | 2003 | 12659295 |
| a predator's dilemma: prey choice and parasite susceptibility in three-spined sticklebacks. | the acanthocephalan parasite pomphorhynchus laevis is transmitted by a suitable intermediate host such as the amphipod gammarus pulex to its definitive fish host. parasite-induced alterations in both appearance and behaviour concur to render infected gammarids more vulnerable to predation, thus promoting parasite transmission. experimental infection of laboratory bred full- and half-sib groups of three-spined sticklebacks (gasterosteus aculeatus) provided evidence that the parasite imposes a sur ... | 2003 | 12741513 |
| effects of experimental schistocephalus solidus infections on growth, morphology and sexual development of female three-spined sticklebacks, gasterosteus aculeatus. | the use of naturally infected hosts in studies attempting to identify parasite-induced changes in host biology is problematical because it does not eliminate the possibility that infection may be a consequence, rather than a cause, of host trait variation. in addition, uncontrolled concomitant infections may confound results. in this study we experimentally infected individual laboratory-bred female three-spined sticklebacks gasterosteus aculeatus l. with the pseudophyllidean cestode schistoceph ... | 2003 | 12741515 |
| the consequences of self-fertilization and outcrossing of the cestode schistocephalus solidus in its second intermediate host. | many hermaphroditic parasites reproduce by both cross-fertilization and self-fertilization. to understand the maintenance of such mixed mating systems it is necessary to compare the fitness consequences of the two reproductive modes. this has, however, almost never been done in the context of host-parasite coevolution. here we show the consequences of outcrossing and selfing in an advanced life-stage of the cestode schistocephalus solidus, i.e. in its second intermediate host, the three-spined s ... | 2003 | 12741516 |
| size-dependent selection on arrival times in sticklebacks: why small males arrive first. | studies on arrival time to breeding areas show that high-quality males usually arrive first and gain the highest reproductive success. this is generally assumed to be due to phenotype-dependent costs and benefits of early arrival. we show that the opposite arrival order can occur, probably due to selection on poor-quality males to increase their chances of reproduction. in a fish species, the threespine stickleback, gasterosteus aculeatus, small males arrived before larger males at the breeding ... | 2003 | 12778555 |
| the crossroads of molecular, typological and biological species concepts: two new species of gyrodactylus nordmann, 1832 (monogenea: gyrodactylidae). | nucleotide sequences of nuclear ribosomal dna internal transcribed spacers (its) were used to confirm morphological identification of gyrodactylus species in fennoscandia. three pairs of morphologically similar or cryptic species are compared in this study. g. branchicus malmberg, 1964 and g. rarus wegener, 1910, hosted by the sticklebacks gasterosteus aculeatus l. and pungitius pungitius (l.), respectively, displayed a genetic divergence of 0.9-1.3% along 774 nucleotides of its (jukes & cantor ... | 2003 | 12815215 |
| locomotory capacity of baltic sea and freshwater populations of the threespine stickleback (gasterosteus aculeatus). | two freshwater populations and one marine population (baltic sea) of threespine stickeback (gasterosteus aculeatus) from northeastern germany were studied with regard to locomotory capacity: sustained swimming performance, activities of key enzymes in axial muscle, pectoral fin muscle and heart, and morphology. we postulated that life history differences between migratory baltic sea and resident freshwater populations could have led to a divergence in their locomotory capacity. the activity of c ... | 2003 | 12829049 |
| schistocephalus solidus: a molecular test of premature gamete exchange for fertilization in the intermediate host gasterosteus aculeatus. | we tested the hypothesis that the cestode schistocephalus solidus is capable of premature gamete exchange as a plerocercoid in the last intermediate stickleback host. the existence of such a reproductive mode is suggested by the highly advanced gonadal development in the plerocercoid and the large fitness gain of outcrossing. in addition, eggs from selfing cestodes have a higher hatching rate when the cestode originated from a doubly infected stickleback than when it came from a singly infected ... | 2003 | 12880596 |
| seasonal variations in the incidence and development of the cestode proteocephalus filicollis (rud. 1810) in gasterosteus aculeatus (l. 1766). | | 1959 | 14403032 |
| multiple parasites are driving major histocompatibility complex polymorphism in the wild. | parasite mediated selection may result in arms races between host defence and parasite virulence. in particular, simultaneous infections from multiple parasite species should cause diversification (i.e. balancing selection) in resistance genes both at the population and the individual level. here, we tested these ideas in highly polymorphic major histocompatibility complex (mhc) genes from three-spined sticklebacks (gasterosteus aculeatus l.). in eight natural populations, parasite diversity (15 ... | 2003 | 14635861 |
| speciation and host-parasite relationships in the parasite genus gyrodactylus (monogenea, platyhelminthes) infecting gobies of the genus pomatoschistus (gobiidae, teleostei). | using species-level phylogenies, the speciation mode of gyrodactylus species infecting a single host genus was evaluated. eighteen gyrodactylus species were collected from gobies of the genus pomatoschistus and sympatric fish species across the distribution range of the hosts. the v4 region of the ssrrna and the internal transcribed spacers encompassing the 5.8s rrna gene were sequenced; by including published sequences a total of 30 species representing all subgenera were used in the data analy ... | 2003 | 14636683 |
| optimal mechanisms for finding and selecting mates: how threespine stickleback ( gasterosteus aculeatus) should encode male throat colors. | male threespine stickleback ( gasterosteus aculeatus) use nuptial colors to attract mates and intimidate rivals. we quantified stickleback color and environmental lighting using methods independent of human perception to evaluate the information transmitted by male signals in a habitat where these signals are displayed. we also developed models of chromatic processing based on four cone photopigments (peak absorptions at 360, 445, 530, and 605 nm) characterized microspectrophotometrically in g. ... | 2004 | 14752565 |
| [a comparative biochemical research in the schistocephalus solidus (cestoda)--three-spined stickleback gasterosteus aculeatus l. system]. | the activity of five lysosomal hydrolases (acid phosphatase, dnaase, rnaase, beta-glucosidase, beta-galactosidase), alkaline phosphatase and aldolase have been examined in tissues of the cestode schistocephalus solidus (müller, 1776) and the three-spined stickleback gasterosteus aculeatus (l.) forming a stable parasite-host system. as a rule, the activity of enzymes was higher in a cestode body than in fish tissues. the acid and alkaline phosphatases were the exception. the activity and variatio ... | 2003 | 14964851 |
| major histocompatibility complex diversity influences parasite resistance and innate immunity in sticklebacks. | proteins of the major histocompatibility complex (mhc) play a central role in the presentation of antigens to the adaptive immune system. the mhc also influences the odour-based choice of mates in humans and several animal taxa. it has recently been shown that female three-spined sticklebacks (gasterosteus aculeatus) aim at a moderately high mhc diversity in their offspring when choosing a mate. do they optimize the immune systems of their offspring? using three-spined sticklebacks that varied i ... | 2004 | 15058398 |
| immunohistochemistry, histopathology and ultrastructure of gasterosteus aculeatus tissues infected with glugea anomala. | immunohistochemical and histopathological studies were conducted on a population of 3-spined sticklebacks gasterosteus aculeatus (l.) from loch airthrey (stirling, scotland) naturally infected with the microsporean glugea anomala (moniez 1887). of the 55 host specimens that were examined, 16 (29.09%) were infected, the intensity of infection ranging from 1 to 4 xenomas per fish, which were principally located within the central portion of the body lateral flank musculature. all 32 g. anomala xen ... | 2004 | 15109142 |
| ellipsomyxa gobii (myxozoa: ceratomyxidae) in the common goby pomatoschistus microps (teleostei: gobiidae) uses nereis spp. (annelida: polychaeta) as invertebrate hosts. | nereis diversicolor o.f. müller and n. succinea frey et leuckart (polychaeta, nereidae) living in brackish shallow areas in denmark are naturally infected with tetractinomyxon actinospores. infected nereis spp. were experimentally fed to various potential fish hosts, and the actinosporean stages developed into myxosporean stages of ellipsomyxa gobii køie, 2003 (ceratomyxidae) in the gallbladder of the common goby pomatoschistus microps (krøyer) (gobiidae). the european eel anguilla anguilla (l.) ... | 2004 | 15139372 |
| modulation of granulocyte responses in three-spined sticklebacks gasterosteus aculeatus infected with the tapeworm schistocephalus solidus. | leukocytes isolated from the head kidney and peripheral blood of 3-spined sticklebacks gasterosteus aculeatus l. were analysed by means of flow cytometry during infection with the tapeworm schistocephalus solidus (müller, 1776). although parasites increased their body weight continuously throughout the observation period (98 d), proportions of granulocytes increased in blood and head kidney only up to day 63 post-infection (p.i.). thereafter, declining proportions of granulocytes were observed i ... | 2004 | 15212281 |
| assessment and assortment: how fishes use local and global cues to choose which school to go to. | animals that live in groups are known preferentially to associate with phenotypically similar individuals. despite this, groups of mixed phenotypic composition are the norm rather than the exception in several systems in the wild and this, combined with the large sizes of some animal groups, makes accurate global assessment by a choosing individual more difficult. in this study, we investigated the role of local and global information in mediating shoal-choice decisions in three-spined stickleba ... | 2004 | 15504008 |
| the juvenile three-spined stickleback (gasterosteus aculeatus l.) as a model organism for endocrine disruption. i. sexual differentiation. | juvenile three-spined stickleback (gasterosteus aculeatus l.) is introduced as a unique model organism for both androgenic and oestrogenic endocrine action. intersex is often used as an indicator for disruption of sexual differentiation in fish exposed to different kinds of effluents from human activities. in wild fish it has exclusively been reported in terms of feminisation due to xenoestrogens in the environment. the assumption that the intersex individuals are feminised genetic males can onl ... | 2004 | 15588641 |
| the juvenile three-spined stickleback (gasterosteus aculeatus l.) as a model organism for endocrine disruption ii--kidney hypertrophy, vitellogenin and spiggin induction. | this study investigated the suitability of juvenile three-spined sticklebacks, gasterosteus aculeatus l., for detecting both androgen- and oestrogen-induced endocrine disruption. the investigated endpoints were kidney hypertrophy and the induction of the protein markers spiggin and vitellogenin. juveniles were exposed to steroid hormones 17 beta-oestradiol (e2: nominal 0.01, 1.0 and 10 microg/l), 17 alpha-ethinylestradiol (ee2: nominal 0.05 microg/l) and 17 alpha-methyltestosterone (mt: nominal ... | 2004 | 15588642 |
| fish host-cestode parasite stable isotope enrichment patterns in marine, estuarine and freshwater fishes from northern canada. | cestode parasites from freshwater (threespine stickleback, gasterosteus aculeatus), estuarine (brook charr, salvelinus fontinalis) and marine (greenland cod, gadus ogac) fish from northern quebec, canada, were used to investigate the hypotheses that cestode parasites are (13)c and (15)n enriched relative to host food sources, but (15)n depleted with respect to host muscle tissue as a result of differential enrichment during the assimilation of common nutrient sources. cestode parasites and fish ... | 2004 | 15621744 |
| parasites grow larger in faster growing fish hosts. | parasites depend on host-derived energy for growth and development, and so are potentially affected by the host's ability to acquire nutrients under competitive foraging scenarios. although parasites might be expected to grow faster in hosts that are better at acquiring nutrients from natural ecosystems, it is also possible that the most competitive hosts are better at countering infections, if they have an improved immune response or are able to limit the availability of nutrients to parasites. ... | 2005 | 15710434 |
| the clearance of hidden cestode infection triggered by an independent activation of host defense in a teleost fish. | parasites often elude effective recognition or attack (or both) by the host immune system, for example, though a tegument that possesses nonimmunogenic features. however, a general activation of host defense due to independent stimuli may increase immune activity to a level where such disguises are no longer effective, resulting in the clearance of an infection. we experimentally infected three-spined sticklebacks (gasterosteus aculeatus) with the cestode schistocephalus solidus. to independentl ... | 2004 | 15715223 |
| mate choice decisions of stickleback females predictably modified by mhc peptide ligands. | sexual selection has been proposed as one mechanism to explain the maintenance of high allelic diversity in mhc genes that control the extent of resistance against pathogens and parasites in natural populations. mhc-based sexual selection is known to involve olfactory mechanisms in fish, mice, and humans. during mate choice, females of the three-spined stickleback (gasterosteus aculeatus) use an odor-based selection strategy to achieve an optimal level of mhc diversity in their offspring, equipp ... | 2005 | 15755811 |
| [parasite fauna in sticklebacks (gasterosteidae) from bodies of water of the kola region]. | the results of a parasitological study of the two species of sticklebacks (pungitius pungitius and gasterosteus aculeatus) inhabiting the kola region are presented. the 42 and 14 species of parasite were found in the nine-spined and three-spined stickleback, respectively. the paucity of the parasite fauna in the three-spined stickleback is observed. distribution of parasites in kola waterbodies and ecological peculiarities in system "parasite-host" are presented. | 2005 | 15810555 |
| costs and limits of dosage response to predation risk: to what extent can tadpoles invest in anti-predator morphology? | inducible defences have long been considered as a polyphenism opposing defended and undefended morphs. however, in nature, preys are exposed to various levels of predation risk and scale their investment in defence to actual predation risk. still, among the traits that are involved in the defence, some are specific to one predator type while others act as a more generalised defence. the existence of defence costs could prevent an individual investing in all these traits simultaneously. in this s ... | 2005 | 16001226 |
| habitat dependent associations between parasitism and fluctuating asymmetry among endemic stickleback populations. | inconsistencies in the relationship between fluctuating asymmetry (fa) and fitness may be due to selection acting on the degree of trait asymmetry that differs among populations or among traits. we assessed relationships between parasite susceptibility and fluctuating asymmetry in the number of bony lateral plates among 83 populations of freshwater gasterosteus aculeatus (three spined stickleback) and among lateral plate positions that vary in the selection they experience for symmetry. the corr ... | 2005 | 16033566 |
| ultraviolet light and visual behaviour in the three-spined stickleback, gasterosteus aculeatus. | the ability of various vertebrates to perceive visual information in the ultraviolet region of the electromagnetic spectrum (300-400 nm) is receiving increasing interest. to date, many of these studies have concentrated on the role of ultraviolet perception in mate choice, yet there are several ways in which the ability to perceive ultraviolet information may affect other behaviours. until now, it has been widely assumed that colour in the three-spined stickleback can be quantified by methods ap ... | 2005 | 16082613 |
| molecular cloning and characterization of a nuclear androgen receptor activated by 11-ketotestosterone. | although 11-ketotestosterone is a potent androgen and induces male secondary sex characteristics in many teleosts, androgen receptors with high binding affinity for 11-ketotestosterone or preferential activation by 11-ketotestosterone have not been identified. so, the mechanism by which 11-ketotestosterone exhibits such high potency remains unclear. recently we cloned the cdna of an 11-ketotestosterone regulated protein, spiggin, from three-spined stickleback renal tissue. as spiggin is the only ... | 2005 | 16107211 |
| effect of australian tea tree oil on gyrodactylus spp. infection of the three-spined stickleback gasterosteus aculeatus. | gyrodactylus spp. infections of commercially farmed fishes are responsible for significant economic losses. existing treatments have proved uneconomic, stressful to the fishes, and ecologically damaging. essential oils are naturally occurring compounds that exhibit a wide range of anti-microbial and anti-fungal activities. this study explored the possibility of using australian tea tree (melaleuca alternifolia) oil (tto) to treat gyrodactylus spp. infection on the three-spined stickleback gaster ... | 2005 | 16175965 |
| comparing host and parasite phylogenies: gyrodactylus flatworms jumping from goby to goby. | the combination of exceptionally high species diversity, high host specificity, and a complex reproduction system raises many questions about the underlying mechanisms triggering speciation in the flatworm genus gyrodactylus. the coevolutionary history with their goby hosts was investigated using both topology- and distance-based approaches; phylogenies were constructed of the v4 region of the 18s rrna and the complete its rdna region for the parasites, and 12s and 16s mtdna fragments for the ho ... | 2005 | 16195215 |
| surface carbohydrate composition of a tapeworm in its consecutive intermediate hosts: individual variation and fitness consequences. | carbohydrates on parasite surfaces have been shown to play an important role in host-parasite coevolution, mediating host non-self recognition and parasite camouflage. parasites that switch hosts can change their surface molecules to remain undetected by the diverse immune systems of their different hosts. however, the question of individual variation in surface sugar composition and its relation to infectivity, virulence, immune evasion and growth of a parasite in its different hosts is as yet ... | 2005 | 16198355 |
| [arctic teleost fishes with canceled accelerated senescence program are a potential source of stress protectors and cancer drugs]. | a new approach to the development of natural cancer drugs from hydrobionts selected for longevity and stress resistance is analyzed. the accelerated senescence program was successfully canceled in holarctic stickleback gasterosteus aculeatus by crossing the marine and freshwater forms in ponds and selection of hybrids. prolongation of fish life was accompanied by an increased production of the antistress exocrine secretion by the renal epithelium of male sticklebacks (glycoproteins, peptides, an ... | 2005 | 16240755 |
| evolutionary implications of the adaptation to different immune systems in a parasite with a complex life cycle. | many diseases are caused by parasites with complex life cycles that involve several hosts. if parasites cope better with only one of the different types of immune systems of their host species, we might expect a trade-off in parasite performance in the different hosts, that likely influences the evolution of virulence. we tested this hypothesis in a naturally co-evolving host-parasite system consisting of the tapeworm schistocephalus solidus and its intermediate hosts, a copepod, macrocyclops al ... | 2005 | 16271977 |
| a checklist of parasites recorded on sticklebacks (actinopterygii: gasterosteidae) from poland. | parasites of the three-spined stickleback, gasterosteus aculeatus (l.), and the nine-spined stickleback, pungitius pungitius (l.), from brackish and freshwater habitats in poland are listed. the following list was compiled from published records and own long-term studies. parasites are listed alphabetically in meaningful groups of parasites with notes about their location on the host and distribution in poland with references. a total of 51 species (taxa) of parasites were recorded on g. aculeat ... | 2006 | 16343983 |
| local differences in immunocompetence reflect resistance of sticklebacks against the eye fluke diplostomum pseudospathaceum. | we investigated population differences in immunological adaptation of three-spined sticklebacks (gasterosteus aculeatus) to one of their most abundant macroparasites, the eye fluke diplostomum pseudospathaceum. we compared infection success in lab-bred fish of 2 populations in northern germany, from a lake, where eye flukes are prevalent, and a river, where these parasites do not occur. in order to discriminate between protection through innate and acquired immunity, we exposed fish either only ... | 2006 | 16393359 |
| ornaments or offspring? female sticklebacks (gasterosteus aculeatus l.) trade off carotenoids between spines and eggs. | hypotheses and models to explain female ornaments often assume that the elaborated traits are condition dependent; nevertheless, few empirical studies have addressed this topic. we studied a population of three-spined sticklebacks (gasterosteus aculeatus) in which the females have conspicuous, carotenoid-based red coloration to their pelvic spines. the red coloration seems not to be condition dependent, as coloration is negatively associated with age and body length and not associated with condi ... | 2006 | 16599919 |
| transfer of nodularin to three-spined stickleback (gasterosteus aculeatus l.), herring (clupea harengus l.), and salmon (salmo salar l.) in the northern baltic sea. | nodularin (nodln) is a hepatotoxin produced by the cyanobacterium nodularia spumigena, which occurs regularly in the baltic sea. the primary aim of this study was to study the transfer of nodln to three-spined stickleback (gasterosteus aculeatus l.), herring (clupea harengus membras l.), and salmon (salmo salar l.), which were caught from the northern baltic sea between august 2002 and august 2003. liquid chromatography mass spectrometry (lc-ms) was used for nodln analysis. nodln was found in bo ... | 2007 | 16616370 |
| uv matters in shoaling decisions. | shoaling behaviour in fish is influenced by numerous factors, such as familiarity, kinship, group size and shoal composition. grouping decisions are based on both olfactory and visual cues. the visual system of many vertebrates is extended into the ultraviolet (uv) wave range as in three-spined sticklebacks (gasterosteus aculeatus, l.). we investigated whether the presence or absence of uv wavelengths has an influence on shoaling behaviour in this species. reproductively non-active three-spined ... | 2006 | 16618679 |
| resveratrol and the pharmacology of aging: a new vertebrate model to validate an old molecule. | the natural phytoalexin resveratrol, found in grapes and red wine, recently rose to public fame for its positive effects on longevity in yeasts, worms and flies. resveratrol anti-cancer and anti-inflammatory in vitro action on mammalian cell cultures also suggest a possible positive effect on human health and life-expectancy. to study the effects of resveratrol on vertebrate aging is obviously a particularly relevant question. we have studied resveratrol effects in a very short-lived vertebrate: ... | 2006 | 16687936 |
| parasites of sticklebacks (actinopterygii: gasterosteidae) from south-eastern baltic sea (poland). | a total of 142 individuals of gasterosteus aculeatus l. and 22 individuals of pungitius pungitius (l.) from several areas of the coastal waters of the gdańsk bay both brackish- and freshwater were examined for parasites. the survey was carried out within 1988-1991. six parasite species, namely: gyrodactylus arcuatus, apatemon gracilis, sphaerostomum bramae, phyllodistomumfolium, neoechinorhynchus rutili, and argulus foliaceus were recovered from sticklebacks caught in freshwater habitats; while ... | 2005 | 16838625 |
| emerging developmental model systems. | this primer briefly describes four emerging animal model systems that promise to provide insights into specific aspects of developmental biology. highlighted here are two relatively well-characterized model systems, gasterosteus aculeatus (three-spine stickleback fish) and schmidtea mediterranea (planarian), as well as two organisms on which research is in its infancy, carollia perspicillata (short-tailed fruit bat), and the basal metazoan, trichoplax adhaerens. scientists who helped develop the ... | 2006 | 16881053 |
| seasonal variation of parasite infection of three-spined stickleback (gasterosteus aculeatus l.) in the southern baltic. | seasonal changes of infection were observed in the case of some species of ectoparasites: trichodina domerguei domerguei, t. tenuidens, gyrodactylus arcuatus, and thersitina gasterostei, as well as for endoparasites: glugea anomala, schistocephalus solidus, diphyllobothrium ditremum, and proteocephalus filicollis. same seasonal changes in frequency of developmental stages were observed in the case of females t. gasterostei. the highest level of infection with ectoparasites was observed in spring ... | 2002 | 16894719 |
| schistocephalus cotti n. sp. (cestoda: pseudophyllidea) plerocercoids from bullheads cottus gobio l. in an arctic river in finland, with a key to the plerocercoids of the palaearctic species of the genus. | we compared plerocercoids of schistocephalus creplin, 1829 from cottus gobio (n = 57) and gasterosteus aculeatus f. semiarmatus (n = 45) from the river utsjoki, finland, taken only from single worm infections. segment numbers in the two populations were distinct (g. aculeatus range 55-107, average 74 (se 1.66), median 73; c. gobio range 122-189, average 146 (se 1.78); median 144). the mean difference between populations, 71.47, t = 28.76 with 100 degrees of freedom, two-tailed p value <0.001, wa ... | 2006 | 16944267 |
| parallel genetic origins of pelvic reduction in vertebrates. | despite longstanding interest in parallel evolution, little is known about the genes that control similar traits in different lineages of vertebrates. pelvic reduction in stickleback fish (family gasterosteidae) provides a striking example of parallel evolution in a genetically tractable system. previous studies suggest that cis-acting regulatory changes at the pitx1 locus control pelvic reduction in a population of threespine sticklebacks (gasterosteus aculeatus). in this study, progeny from in ... | 2006 | 16945911 |
| first report of gyrodactylus spp. (platyhelminthes: monogenea) in the western mediterranean sea: molecular and morphological descriptions. | the gyrodactylus spp. fauna on species of gobies, pomatoschistus, gobiusculus, and knipowitschia (gobiidae: teleostei), from the western mediterranean and adriatic seas is strikingly similar to that found in the baltic sea and eastern atlantic ocean, both in morphology and in internal transcribed spacer (its) rrna. the fauna consisted of gyrodactylus branchialis, g. ostendicus, g. gondae, g. rugiensis, g. rugiensoides, and g. arcuatus. no new species have been found. a morphometric comparison be ... | 2006 | 16995382 |
| directional asymmetry of pelvic vestiges in threespine stickleback. | extensive reduction of the size and complexity of the pelvic skeleton (i.e., pelvic reduction) has evolved repeatedly in gasterosteus aculeatus. asymmetrical pelvic vestiges tend to be larger on the left side (i.e., left biased) in populations studied previously. loss of pitx1 expression is associated with pelvic reduction in g. aculeatus, and pelvic reduction maps to the pitx1 locus. pitx1 knockouts in mice have reduced hind limbs, but the left limb is larger. thus left-biased directional asymm ... | 2007 | 17016807 |
| contrasting patterns of body shape and neutral genetic divergence in marine and lake populations of threespine sticklebacks. | comparisons of neutral marker and quantitative trait divergence can provide important insights into the relative roles of natural selection and neutral genetic drift in population differentiation. we investigated phenotypic and genetic differentiation among fennoscandian threespine stickleback (gasterosteus aculeatus) populations, and found that the highest degree of differentiation occurred between sea and freshwater habitats. within habitats, morphological divergence was highest among the diff ... | 2006 | 17040377 |
| changed environmental conditions weaken sexual selection in sticklebacks. | environmental heterogeneity can cause the intensity and direction of selection to vary in time and space. yet, the effects of human-induced environmental changes on sexual selection and the expression of mating traits of native species are poorly known. currently, the breeding habitats of the three-spined stickleback gasterosteus aculeatus are changing in the baltic sea because of eutrophication and increased growth of algae. here we show that enhanced growth of filamentous algae increases the c ... | 2007 | 17210016 |
| schistocephalus solidus: establishment of tapeworms in sticklebacks--fast food or fast lane? | the penetration of the intestinal mucosal wall is supposed to be critical for helminth parasite infestation, but has rarely been analyzed in detail. we here studied the establishment process of schistocephalus solidus tapeworms in their second intermediate host, the three-spined stickleback, from oral uptake after experimental exposure, to passage through the gastro-intestinal tract and arrival in the fish body cavity. using histological techniques, we found tapeworms to penetrate the intestine ... | 2007 | 17296178 |
| isolation of viral haemorrhagic septicaemia virus from mummichog, stickleback, striped bass and brown trout in eastern canada. | viral haemorrhagic septicaemia virus (vhsv) was isolated from mortalities occurring in populations of mummichog, fundulus heteroclitus, stickleback, gasterosteus aculeatus aculeatus, brown trout, salmo trutta, and striped bass, morone saxatilis, in new brunswick and nova scotia, canada. the isolated viral strains produced a cytopathic effect on the epithelioma papillosum cyprini cell line. serum neutralization indicated the virus was vhsv and sequencing identified the rhabdovirus isolates as the ... | 2007 | 17394523 |
| habitat-specific adaptation of immune responses of stickleback (gasterosteus aculeatus) lake and river ecotypes. | freshwater populations of three-spined sticklebacks (gasterosteus aculeatus) in northern germany are found as distinct lake and river ecotypes. adaptation to habitat-specific parasites might influence immune capabilities of stickleback ecotypes. here, naive laboratory-bred sticklebacks from lake and river populations were exposed reciprocally to parasite environments in a lake and a river habitat. sticklebacks exposed to lake conditions were infected with higher numbers of parasite species when ... | 2007 | 17426014 |