| remarks on eimeria cotti from the intestine of bullhead (cottus gobio). | eimeria cotti, a gut dwelling coccidian parasite from bullhead (cottus gobio) is described from fish collected from waters of a natural resort area in north-west germany. all age groups of bullhead were found to be infected throughout the year at a prevalence of 43 out of 92 fish examined. infected tissue contained merogonic, gamogonic and sporogonic developmental stages. ultrastructural features of these stages conformed with those of other eimerian coccidia. merozoites were formed by ectomerog ... | 1994 | 8173584 |
| [gyrodactylus onegensis sp. n. (monogenea)--a parasite of the bullhead (cottus gobio l.)]. | a new species, gyrodactylus onegensis sp. n., is described from gills of the freshwater sculpin cottus gobio. | 2000 | 10862404 |
| 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 |
| genetic analysis of potential postglacial watershed crossings in central europe by the bullhead (cottus gobio l.). | natural colonizations across watersheds have been frequently proposed to explain the present distributions of many freshwater fish species. however, detailed studies of such potential watershed crossings are still missing. here, we investigated potential postglacial watershed crossings of the widely distributed european bullhead (cottus gobio l.) in two different areas along the rhine-rhône watershed using detailed genetic analysis. the main advantage of studying bullheads vs. other freshwater f ... | 2007 | 17908217 |
| increased susceptibility to predation and altered anti-predator behaviour in an acanthocephalan-infected amphipod. | according to the 'parasitic manipulation hypothesis', phenotypic changes induced by parasites in their intermediate hosts are effective means of increasing trophic transmission to final hosts. one obvious prediction, although seldom tested, is that increased vulnerability of infected prey to an appropriate predator should be achieved by the parasite altering the anti-predator behaviour of its intermediate host. in this study, we tested this prediction using the fish acanthocephalan pomphorhynchu ... | 2007 | 17258219 |
| evidence that elevated water temperature affects the reproductive physiology of the european bullhead cottus gobio. | climate change is predicted to increase the average water temperature and alter the ecology and physiology of several organisms including fish species. to examine the effects of increased water temperature on freshwater fish reproduction, adult european bullhead cottus gobio of both genders were maintained under three temperature regimes (t1: 6-10, t2: 10-14 and t3: 14-18°c) and assessed for gonad development (gonadosomatic index-gsi and gonad histology), sex steroids (testosterone-t, 17β-estrad ... | 2012 | 21638008 |
| the importance of incorporating age and sex when backcalculating length in bullhead cottus gobio. | the present study backcalculated body length for a data set of a bullhead cottus gobio population located at different sampling sites in a river network. model comparison between various growth models, which included successively new parameters, showed the effect and importance of taking sex, age and the location in the river network into account. the data sets obtained by backcalculation were fitted by the von bertalanffy growth function, which revealed the effect of the backcalculation formula ... | 2011 | 21539555 |
| proteasome and antioxidant responses in cottus gobio during a combined exposure to heat stress and cadmium. | temperature and trace metals are common environmental stressors, and their importance is increasing due to global climate change and anthropogenic pollution. oxidative damage and antioxidant properties have been studied in liver and gills of the european bullhead (cottus gobio) subjected to cadmium (cdcl(2) at nominal concentrations of 0.01 and 1mg/l) for 4 days at either 15°c or 21°c. first, exposure to 1mg cd/l induced a high mortality rate (67%) in fish held at 21°c. regarding the antioxidant ... | 2012 | 22033351 |
| effects of cadmium exposure on the gill proteome of cottus gobio: modulatory effects of prior thermal acclimation. | temperature and trace metals are common environmental stressors, and their importance is increasing due to global climate change and anthropogenic pollution. the aim of the present study was to investigate whether acclimation to elevated temperature affects the response of the european bullhead (cottus gobio) to subsequent cadmium (cd) exposure by using enzymatic and proteomic approaches. fish acclimated to 15 (standard temperature), 18 or 21 °c for 28 days were exposed to 1mg cd/l for 4 days at ... | 2014 | 24874008 |
| detection and apparent survival of pit-tagged stream fish in winter. | environmental fluctuations exert strong control on behavior, survival, and fitness of stream biota. technical improvements increasingly allow for tracking the response of large numbers of individuals to environmental fluctuations, for instance, by remote detection of animals equipped with pit (passive integrated transponder) tags. pit tags were implanted into 393 juvenile and adult brown trout salmo trutta l. and european sculpin cottus gobio l. in a boreal stream subjected to considerable ice f ... | 2016 | 27066238 |
| squamous cell carcinoma in a wild european bullhead cottus gobio. | a pharyngeal tumor was found in a wild european bullhead. the tumor mass appeared underneath the operculum and was bilobed. the major neoplastic component showed diffuse epithelial squamous differentiation. crossmonn's trichrome allowed identification of connective tissues whereas no neoplastic cells were stained. periodic acid-schiff was negative within the mass, and giemsa did not show any further diagnostic significance. immunohistochemistry showed diffuse positive cytoplasmic staining of the ... | 2016 | 27901506 |
| habitat use by the fish assemblages of two chalk streams | patterns of habitat use by fish assemblages in two chalk streams in southern england were examined to identify species preferences with respect to major habitat gradients. both study sites, although differing in some physical habitat characteristics, mainly channel width, water temperature and instream cover, could be arranged similarly along a continuum extending from erosional to depositional habitats. twelve fish species were collected from stream surveys conducted during july 1993. the habit ... | 1997 | 9236089 |
| manipulative parasites may not alter intermediate host distribution but still enhance their transmission: field evidence for increased vulnerability to definitive hosts and non-host predator avoidance. | behavioural alterations induced by parasites in their intermediate hosts can spatially structure host populations, possibly resulting in enhanced trophic transmission to definitive hosts. however, such alterations may also increase intermediate host vulnerability to non-host predators. parasite-induced behavioural alterations may thus vary between parasite species and depend on each parasite definitive host species. we studied the influence of infection with 2 acanthocephalan parasites (echinorh ... | 2013 | 23068018 |
| [the role of paratenic hosts in the life cycles of helminths]. | paratenic hosts, especially of nematodes, play a major role in spreading many parasite species. the phenomenon of "paratenic parasitism" is illustrated by examples of development of syngamus trachea and proteocephalus longicollis. moravec introduced a concept of "natural paratenic host" for p. longicollis infecting common sculpion, cottus gobio, in europe. according to kennedy, paratenic host richness of anguillicola crassus is an adaptation to new environmental conditions. new studies, involvin ... | 2008 | 19338219 |
| isolation and characterization of polymorphic microsatellite loci in the european bullhead cottus gobio l. (osteichthyes) and their applicability to related taxa. | | 1999 | 10620244 |
| the evolution of fish ectoparasite communities--the role of the ice ages. | the monogenean ectoparasite genera dactylogyrus and gyrodactylus are hyperdiverse, and yet monogenean communities infecting freshwater fish in the northern holarctic are variable and often impoverished. this is a result of extinctions during periods of glaciation when the host fishes experienced range contraction. fish species recolonised northern europe by one of three routes; stenohaline fishes recolonised from the black sea basin via danube-rhine or dnieper-dniester-vistula connections. these ... | 2008 | 19338218 |
| habitat segregation mediates predation by the benthic fish cottus gobio on the exotic amphipod species gammarus roeseli. | predation is often considered as one of the most important biotic factor determining the success of exotic species. the freshwater amphipod gammarus roeseli has widely colonized western europe, where it is frequently found in sympatry with the native species (gammarus pulex). previous laboratory experiments revealed that g. roeseli may have an advantage over g. pulex through differential predation by native fish (brown trout). morphological anti-predator defences (spines) were found responsible ... | 2008 | 18523749 |
| histological studies on the effects of apatemon cobitidis in its second intermediate host, the bullhead (cottus gobio). | pathological effects of apatemon cobitidis (trematoda) in its second intermediate host, the bullhead (cuttus gobio) are described. macroscopically pathology in bullheads is characterized by migrating and encysted metacercariae in body cavity, eyes, retrobulbous space, brain and rarely in muscles and subcutis. histologically lymphohistiocytic reactions and hemorrhages could be observed. migration of metacercariae in eyes and invasion of brain causes blindness and inability to adapt to the backgro ... | 1991 | 2039089 |
| modification of hosts' behavior by a parasite: field evidence for adaptive manipulation. | parasites relying on trophic transmission to complete their life cycles often induce modifications of their host's behavior in ways that may increase their susceptibility to predation by final hosts. these modifications have often been interpreted as parasite adaptations, but very few studies have demonstrated that host manipulation has fitness benefits for the parasite. the aim of the present study was to address the adaptive significance of parasite manipulation by coupling observations of beh ... | 2007 | 18051653 |
| periodic habitat loss alters the competitive coexistence between brown trout and bullheads in a small stream over 34 years. | 1. changes in the population density of juvenile sea trout salmo trutta l. and bullheads cottus gobio l. were compared in a small stream over 34 years. both species have a similar diet and obviously live in the same general habitat. habitat loss was most marked in seven summer droughts: severest in 1976, 1983, 1984, 1995, and less severe but followed by autumn droughts in 1969, 1989 and 1993. the contrasting effects of habitat loss on the two species were examined. 2. for both species, the ricke ... | 2006 | 16903043 |
| histochemical observations on glycoproteins in the urinary apparatus of the bullhead cottus gobio l. and the bull rout myoxocephalus scorpius (l.). | the distribution of neutral and acid (sialylated and sulfated) glycoprotein in the urinary apparatus of a marine and a fresh water cottid teleost (bull rout and bullhead) has been studied. the renal morphology of the bullhead cottus gobio is similar to that of the marine bullrout myoxocephalus scorpius: the glomerular nephron consists of 2 tubular segments (pi and pii), leading to the collecting duct-archinephric duct system (cd/ad). sialoglycoprotein is present in the secretion of the proximal ... | 1982 | 7102034 |
| a genetic map of cottus gobio (pisces, teleostei) based on microsatellites can be linked to the physical map of tetraodon nigroviridis. | to initiate qtl studies in the nonmodel fish cottus gobio we constructed a genetic map based on 171 microsatellite markers. the mapping panel consisted of f1 intercrosses between two divergent cottus lineages from the river rhine system. basic local alignment search tool (blast) searches with the flanking sequences of the microsatellite markers yielded a significant (e < 10(-5)) hit with the tetraodon nigroviridis genomic sequence for 45% of the cottus loci. remarkably, most of these hits were d ... | 2005 | 16313473 |
| the response of stream-dwelling fish to liming. | the fish fauna in 22 limed and seven unlimed small streams was monitored using yearly electrofishing to assess the effects of liming on species occurrence and abundance. the liming techniques were divided into three main methods, lake liming, doser liming and wetland liming, to evaluate whether different strategies had different effects on the fish fauna. the predominant species at the investigated stations were salmonids, mainly brown trout (salmo trutta) and atlantic salmon (salmo salar). othe ... | 1992 | 15091941 |
| observations of dermocystidium sp. infections in bullheads, cottus gobio l., from a river in southern england. | bullheads, cottus gobio, with macroscopic external cysts on the skin and fins measuring up to 3 mm in diameter were detected in the river allen and its tributaries in southern england between 1992 and 1998. the prevalence of these cysts was up to 50% at some sites. examination of cyst contents revealed the presence of numerous spores, typical of the genus dermocystidium, measuring 8 microm in diameter. the parasite developed within well-defined cysts, which were located in the hypodermal connect ... | 2004 | 15049890 |
| common sculpin cottus gobio as a natural paratenic host of proteocephalus longicollis (cestoda: proteocephalidae), a parasite of salmonids, in europe. | common sculpins cottus gobio l. (pisces: cottidae), from the mlýnský brook near ceské zleby in the sumava national park, southwestern bohemia, czech republic, were found to harbour in their intestines juvenile cestodes proteocephalus longicollis (zeder, 1800), a common parasite of holarctic salmonids, with a prevalence of 60% and intensity of 1 to 11 (mean 5) parasites per fish; undoubtedly, these prey fish serve as paratenic hosts. in this locality, the definitive host of p. longicollis is the ... | 2001 | 11463104 |
| phylogeography of the bullhead cottus gobio (pisces: teleostei: cottidae) suggests a pre-pleistocene origin of the major central european populations. | the bullhead cottus gobio is a small, bottom-dwelling fish consisting of populations that have not been subject to transplantations or artificial stocking. it is therefore an ideal model species for studying the colonization history of central european freshwater systems, in particular with respect to the possible influences of the pleistocene glaciation cycles. we sampled cottus populations across most of its distribution range, with a special emphasis on southern germany where the major europe ... | 2000 | 10849287 |
| colonization and establishment of pomphorhynchus laevis (acanthocephala) in an isolated english river. | the successful colonization, establishment and spread of pomphorhynchus laevis in a small, isolated, devon river 128 km from the parasite's nearest focus in dorset was followed over 11 years from 1985. the parasite was first detected in anguilla anguilla and platichthys flesus in 1988: by 1995 it had attained prevalence levels of 22.6% in a. anguilla and 43.6% in p. flesus and also occurred in 100% salmo trutta, 50% cottus gobio and noemacheilus barbatulus. as judged by prevalence, abundance, pr ... | 1996 | 8991914 |
| [genetic polymorphism of a pelagic fish species, little baikal oilfish comephorus dybowski, deduced from analysis of microsatellite loci]. | intraspecific genetic polymorphism of a baikal lake endemic, little baikal oilfish (comephorus dybowski korotneff, 1905), was evaluated based on microsatellite analysis. six microsatellite loci designed for the european sculpin, cottus gobio, were used. each locus was typed using 25 to 35 individuals from each of the baikal trenches (southern, middle, and northern). analysis of genetic differentiation (f(st) and r(st)) revealed no statistical significant differences between the samples. the data ... | 2005 | 16152796 |
| an invasive lineage of sculpins, cottus sp. (pisces, teleostei) in the rhine with new habitat adaptations has originated from hybridization between old phylogeographic groups. | fish abundance surveys in the rhine system have shown in the past two decades that there is a rapid upriver invasion of a freshwater sculpin of the genus cottus. these fish are found in habitats that are atypical for the known species cottus gobio, which is confined to small cold streams within the rhine drainage. phylogeographic analysis based on mitochondrial haplotypes and diagnostic single nucleotide polymorphisms indicates that the invasive sculpins are hybrids between two old lineages from ... | 2005 | 16243698 |
| concordant genetic estimators of migration reveal anthropogenically enhanced source-sink population structure in the river sculpin, cottus gobio. | river systems are vulnerable to natural and anthropogenic habitat fragmentation and will often harbor populations deviating markedly from simplified theoretical models. we investigated fine-scale population structure in the sedentary river fish cottus gobio using microsatellites and compared migration estimates from three fst estimators, a coalescent maximum-likelihood method and bayesian recent migration analyses. source-sink structure was evident via asymmetry in migration and genetic diversit ... | 2006 | 16624916 |
| simulation of the physical habitat suitability of bullhead (cottus gobio l.) in the zwalm river. | | 2007 | 18018864 |
| colonization history of the swiss rhine basin by the bullhead (cottus gobio): inference under a bayesian spatially explicit framework. | the present distribution of freshwater fish in the alpine region has been strongly affected by colonization events occurring after the last glacial maximum (lgm), some 20,000 years ago. we use here a spatially explicit simulation framework to model and better understand their colonization dynamics in the swiss rhine basin. this approach is applied to the european bullhead (cottus gobio), which is an ideal model organism to study fish past demographic processes since it has not been managed by hu ... | 2008 | 18194169 |
| effects of temperature on biological and biochemical indicators of the life-history strategy of bullhead cottus gobio. | the biological and biochemical effects of temperature on life-history strategy of female bullhead cottus gobio were investigated. fish from two populations (bez basin, south-east france) experiencing contrasted thermal environments (i.e. more or less stable) were reared during 4 months at three distinct temperatures (7, 9 or 12 degrees c). both somatic (soma fresh mass and muscle triglyceride content) and reproductive (gonad fresh mass, fecundity, mean diameter of eggs and gonad triglyceride con ... | 2009 | 20738623 |
| proteomic response to sublethal cadmium exposure in a sentinel fish species, cottus gobio. | the present study aimed at evaluating the toxicity of short-term cadmium (cd) exposure in the european bullhead cottus gobio, a candidate sentinel species. several enzymatic activity assays (citrate synthase, cytochrome c oxidase, and lactate dehydrogenase) were carried out in liver and gills of fish exposed to 0.01, 0.05, 0.25, and 1 mg cd/l for 4 days. exposure to high cd concentrations significantly altered the activity of these enzymes either in liver and/or in gills. second, 2d-dige techniq ... | 2011 | 21070074 |
| ecotoxicoproteomics in gills of the sentinel fish species, cottus gobio, exposed to perfluorooctane sulfonate (pfos). | the environmental persistence, bioaccumulative tendency and potential toxicity of perfluorooctane sulfonate (pfos) have generated great concern. this study aimed at evaluating the toxicity of short-term pfos exposure in gills of the european bullhead cottus gobio, a candidate sentinel species, by monitoring the response of some enzymes (citrate synthase cs, cytochrome c oxidase cco, and lactate dehydrogenase ldh), and by undertaking a proteomic analysis using 2d-dige. first, a 96-h exposure to 1 ... | 2011 | 21392490 |
| shape based assignment tests suggest transgressive phenotypes in natural sculpin hybrids (teleostei, scorpaeniformes, cottidae). | hybridization receives attention because of the potential role that it may play in generating evolutionary novelty. an explanation for the emergence of novel phenotypes is given by transgressive segregation, which, if frequent, would imply an important evolutionary role for hybridization. this process is still rarely studied in natural populations as samples of recent hybrids and their parental populations are needed. further, the detection of transgressive segregation requires phenotypes that c ... | 2005 | 15987531 |
| [formation of parasite fauna in the bullhead (cottus gobio l.) (pisces: cottidae)]. | the formation of parasite fauna in the bullhead cottus gobio l. in different water bodies was examined. the largest number of parasite species including specific parasites was observed in the onega and ladoga lakes. it is suggested that the host and their parasites migrated namely from these water bodies to other part of the range of the bullhead. | 2007 | 12815816 |
| genetic diversity and condition factor: a significant relationship in flemish but not in german populations of the european bullhead (cottus gobio l.). | although evidence of associations between genetic diversity and fitness in wild species has been published, the lack of a comprehensive review across species and the existence of contradictory results have led to scepticism remaining about its existence and importance in natural populations. in this study, the relationship between genetic diversity at six microsatellite loci and condition factor (a fitness related trait) was investigated at the population level in both flemish and german populat ... | 2002 | 12242644 |
| late glacial history of the cold-adapted freshwater fish cottus gobio, revealed by microsatellites. | the distribution of genetic diversity at 10 highly polymorphic microsatellite loci within the european freshwater fish, cottus gobio, l. was examined. the sampling range comprised a large geographical scale including lineages known to be highly divergent at both mitochondrial dna (mtdna) and allozymes. an analysis of genetic variability within populations showed that expected heterozygosity and allelic richness could be explained largely by current effective population sizes. evidence was found, ... | 2002 | 12207722 |
| spectral tuning and evolution of short wave-sensitive cone pigments in cottoid fish from lake baikal. | the cottoid fishes of lake baikal in eastern siberia provide a unique opportunity to study the evolution of visual pigments in a group of closely related species exposed to different photic environments. members of this species flock are adapted to different depth habitats down to >1000 m, and both the rod and cone visual pigments display short wave shifts as depth increases. the blue-sensitive cone pigments of the sws2 class cluster into two species groups with lambda(max) values of 450 and 430 ... | 2002 | 11993996 |
| postglacial colonization of northern europe by distinct phylogeographic lineages of the bullhead, cottus gobio. | three major phylogeographic lineages of the cottid fish cottus gobio (bullhead) were identified in northern europe from mitochondrial dna sequences and allozyme data. the largely separate freshwater distributions of the lineages demonstrate distinct postglacial colonization histories. west of the baltic sea, swedish lakes were invaded from the southwest (germany). another, eastern lineage has colonized the inland waters northeast and east of the baltic, from refugia in northwest russia; this lin ... | 2001 | 11555242 |
| effects of a benthivorous and a drift-feeding fish on a benthic stream assemblage. | i assessed the impact of both drift-feeding (salmo trutta, brown trout) and benthic-feeding (cottus gobio, bullhead) fish on a benthic assemblage during a 1-month-long field experiment. i used enclosures containing cobble/gravel substrata with 6-mm mesh net that allowed invertebrates to drift freely in and out of enclosures. four treatments, arranged in a factorial design, were tested: a predator-free control, bullheads only (2.67 bullheads/m(2), two per enclosure), brown trout only (2.67 brown ... | 1998 | 28308075 |
| histopathological effects of sublethal exposure to phenol on two variously pre-stressed populations of bullhead (cottus gobio l.). | | 1993 | 8353397 |
| light and electron microscopic studies on myxobolus cotti el-matbouli and hoffmann, 1987 infecting the central nervous system of the bullhead (cottus gobio). | myxobolus cotti (myxozoa: myxosporea) is described as found in the central nervous system of the bullhead (cottus gobio) caught in the alpine lake königssee and in a brook in the bavarian forest, federal republic of germany (el-matbouli and hoffmann 1987). aggregations of spores and polysporoblastic trophozoites compressed and replaced large areas of the white and grey matter of the brain and spinal cord. these aggregations may be surrounded by a thin, connective tissue capsule; in a few cases t ... | 1990 | 2315281 |
| short-term experimental acidification of a welsh stream: toxicity of different forms of aluminium at low ph to fish and invertebrates. | a 24-hr dosing experiment was carried out in a soft-water stream in upland wales during which four separate zones were created by the simultaneous addition of sulphuric acid, aluminium sulphate, and citric acid. an upstream control zone (a), an acid zone ph 4.9 (b), an aluminium and acid (total filterable aluminium 0.27 mg/l, ph 4.9) zone (c) and a downstream zone (d) of aluminium complexed with citrate at low ph (total filterable aluminium 0.23 mg/l, ph 4.9). test species exposed in all zones w ... | 2013 | 2923492 |