Effects of hydropeaking on the spawning behaviour of Atlantic salmon Salmo salar and brown trout Salmo trutta.

Science.gov (United States)

Vollset, K W; Skoglund, H; Wiers, T; Barlaup, B T

2016-06-01

An in situ camera set-up was used to study the spawning activity of Atlantic salmon Salmo salar and brown trout Salmo trutta throughout two consecutive seasons in a spawning area affected by hydropower-related pulse flows due to hydropeaking. The purpose was to test whether the flow variation discouraged spawning in shallow areas or motivated spawning into areas with elevated risk of incubation mortality. There were more S. salar observed on the spawning ground during days with high discharge. The presence of S. salar in the spawning grounds was not affected by the hydropeaking cycles of the preceding night. Female S. salar were observed preparing nests within the first hour after water discharge had increased to levels suitable for spawning. In contrast, the number of S. trutta was not correlated with flow and nest preparation was also observed at a discharge corresponding to the lowest discharge levels during a hydropeaking cycle. Survival was generally high in nests excavated the following winter, with only 5·4% suffering mortality due to dewatering. The results suggest that S. salar may respond rapidly to variable-flow conditions and utilize short windows with suitable flows for spawning. Smaller S. trutta may utilize low-flow conditions to spawn in areas that are not habitable by larger S. salar during low flow. © 2016 The Fisheries Society of the British Isles.

Pressure shock triploidization of Salmo trutta f. lacustris and Salvelinus umbla eggs and its impact on fish development.

Science.gov (United States)

Lahnsteiner, Franz; Kletzl, Manfred

2018-07-15

The study tested the efficiency of hydrostatic pressure triploidization methods for Salmo trutta f. lacustris and Salvelinus umbla and investigated the effects on survival rate, skeletal malformation, and on morphometrics and cellular composition of gills, spleen, liver, kidney, intestine, and blood. In Salmo trutta f. lacustris a 100% triploidy rate in combination with high larvae survival rate (80% in comparison to control) was obtained when treating eggs with a pressure of 66 × 10 3  kPa 360 °C temperature minutes (CTM) post fertilization for 5 min, in Salvelinus umbla with a similar pressure after 270 CTM. Juvenile triploid Salmo trutta f. lacustris and Salvelinus umbla (145 days post hatch) had neither an increased rate of mortality, nor an increased rate of malformations. In triploid Salmo trutta f. lacustris and Salvelinus umbla the erythrocyte volume was 50% higher and the erythrocyte concentration in peripheral blood 25-35% lower relative to diploids. In triploids also the erythrocytes surface area: volume ratio was reduced. Gills of triploid Salmo trutta f. lacustris and Salvelinus umbla had increased width of primary lamellae and increased length of secondary lamellae which might compensate for unfavorable erythrocytes surface area: volume ratio. Length of the digestive tract and histology of kidney, liver, spleen, and gills were only investigated in Salmo trutta f. lacustris. In triploids the hematopoietic tissue of the kidney was decreased by 12%, the spleen index by 53%, and the erythroblast concentrations of the spleen by 42% relative to diploids, possibly indicating reduced erythropoiesis. Length of the digestive tract and cellular arrangement of intestine, liver, and gills were not affected. In summary, the used triploidization procedure seems a reliable method not counteracting the principles of animal welfare. Copyright © 2018 Elsevier Inc. All rights reserved.

Morphological differences in the skin of marble trout Salmo marmoratus and of brown trout Salmo trutta

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Urška Sivka

2012-07-01

Full Text Available Despite being genetically very closely related, the marble trout Salmo marmoratus and the brown trout Salmo trutta exhibit marked phenotypic differences, particularly with regard to skin pigmentation. Histological analysis of skin from the head and gill cover of differently aged individuals of the two species was carried out in order to characterize differences in skin structure. The basic structure of skin of the individuals studied corresponded with that described for other salmonids, though the head epidermis was somewhat thicker in S. marmoratus than in S. trutta, thickening with age in both species. Numerous secretory goblet cells and sporadic secretory sacciform cells were observed in the upper and middle part of the epidermis in both species. Melanophores were present in both species only in the dermis, and were bigger in S. marmoratus and present at lower average density than in S. trutta, and more or less constant across all age classes. In adult S. marmoratus with fully established marble pigmentation, light areas at low density with small (i.e. aggregated melanophores were present, while in S. trutta melanophores were more uniformly distributed.

Predictability of multispecies competitive interactions in three populations of Atlantic salmon Salmo salar.

Science.gov (United States)

Houde, A L S; Wilson, C C; Neff, B D

2015-04-01

Juvenile Atlantic salmon Salmo salar from three allopatric populations (LaHave, Sebago and Saint-Jean) were placed into artificial streams with combinations of four non-native salmonids: brown trout Salmo trutta, rainbow trout Oncorhynchus mykiss, Chinook salmon Oncorhynchus tshawytscha and coho salmon Oncorhynchus kisutch. Non-additive effects, as evidenced by lower performance than predicted from weighted summed two-species competition trials, were detected for S. salar fork length (LF ) and mass, but not for survival, condition factor or riffle use. These data support emerging theory on niche overlap and species richness as factors that can lead to non-additive competition effects. © 2015 The Fisheries Society of the British Isles.

Overwintering of sea trout (Salmo trutta) in freshwater

DEFF Research Database (Denmark)

Thomsen, Dennis; Koed, Anders; Nielsen, Christian

2007-01-01

Brown trout (Salmo trutta) show large phenotypic plasticity. Juveniles may reside in their native freshwater habitat until maturation or migrate into the ocean as 1- to 3-year-old smolts. Sea-going fish (sea trout) reside at sea for 2-3 years until migrating back to their native stream for reprod......Brown trout (Salmo trutta) show large phenotypic plasticity. Juveniles may reside in their native freshwater habitat until maturation or migrate into the ocean as 1- to 3-year-old smolts. Sea-going fish (sea trout) reside at sea for 2-3 years until migrating back to their native stream...... for reproduction. However, immature fish may leave the ocean during their first or second winter at sea and overwinter in freshwater. The question is why does this occur? We tested the hypothesis that hypo-osmoregulatory capacity is compromised by low temperature in two coastal sea trout populations, one...... representing high salinity and the other, low salinity. Immature sea-run trout were caught in lower parts of two rivers during winter and acclimated to laboratory conditions. Subgroups were challenged with high salinity or low water temperature or both, and their osmoregulatory performance was investigated...

The effects of cortisoland actinomycin D injections on choloride cells and branchial N+---K+-ATPase in rainbow trout (Salmo gairdneri)

Science.gov (United States)

Eib, D.W.; Hossner, K.L.

1985-01-01

Injections of cortisol, actinomycin D, or combined administration of the hormone and the antiobiotic did not effect rainbow trout (Salmo gairdneri) branchial Na+K+-ATPase activity. Numbers of chloride cells also did not change following cortisol and actinomycin D treatment. These results are discussed in light of a similar report concerning Atlantic salmon (Salmo salar).

Marine migration and habitat use of anadromous brown trout Salmo trutta

DEFF Research Database (Denmark)

Eldøy, Sindre Håvarstein; Davidsen, Jan Grimsrud; Thorstad, Eva Bonsak

2015-01-01

The biology and ecology of anadromous brown trout (Salmo trutta) at sea is poorly understood. This study provided information on spatial and temporal distribution of sea trout in the ocean. The behaviour of 115 individuals (veteran migrants, 270–700 mm) was tracked by using acoustic telemetry...

A real-time polymerase chain reaction method for the identification of four commercially important salmon and trout species.

Science.gov (United States)

Feng, Junli; Wu, Zhigang; Xie, Xiao; Dai, Zhiyuan; Liu, Shasha

2017-01-01

A duplex quantitative real-time PCR (qPCR) assay was developed for rapid and accurate identification of four commercially important salmon and trout species (Oncorhynchus keta, Oncorhynchus nerka, Oncorhynchus mykiss, and Salmo salar) commonly used for production process of fish in China. The assays targeting the mitochondrial control region (CR) and 16S rRNA gene were able to simultaneously discriminate four target species and the family Salmonidae from processed as well as fresh fish. The qPCR efficiency of each reaction was calculated according to the standard curve, and the method was validated by amplification DNA extracted from single or artificial mixtures prepared with the reference salmon and trout species. Testing of 11 commercial salmon and trout products by the established qPCR assay demonstrated that it was really a useful and academic technique to identify four commercially important salmon and trout species.

Clave ilustrada de los peces chilenos de la familia Serranidae (Teleostei: Perciformes

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Germán Pequeño

2011-03-01

Full Text Available Se presenta una clave para reconocer especies de la familia Serranidae de Chile, que se agrupan en las subfamilias Epinephelinae, Serraninae y Anthiinae. Se proporcionan antecedentes básicos referidos a la taxonomía del grupo, para mayor facilidad del reconocimiento. En cada caso específico, se indica la distribución geográfica e ilustraciones reducidas de las 13 especies de la familia Serranidae que en la actualidad son consideradas en la ictiofauna de Chile.Illustrated key for the Chilean fishes of the family Serranidae (Teleostei: Perciformes. A taxonomic key for identification of fish species of the family Serranidae of Chile, grouped in the subfamilies Epinephelinae, Serraninae and Anthiinae is presented. Basic data about the taxonomic of the group to facilitate the identification is given. In each specific case, the geographical distribution is showed. Reduced illustrations for the currently 13 serranid species considered in the Chilean ichthyofauna are included. Rev. Biol. Trop. 59 (1: 247-253. Epub 2011 March 01.

OLDEST STEM TELEOSTEI FROM THE LATE LADINIAN (MIDDLE TRIASSIC OF SOUTHERN CHINA

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ANDREA TINTORI

2015-11-01

Full Text Available The origin of the largest modern vertebrate group, the Teleostei, saw major refinements in the last decades, thanks to newly discovered and stratigraphically closely spaced Triassic Lagerstätten. Here we report the oldest Pholidophoriformes (stem teleosts that were collected during a large scale yet detailed excavation of Upper Ladinian (Middle Triassic marine deposits in Xingyi City, Guizhou Province, China. Taxonomic comparisons support the erection of a new pholidophorid genus, Malingichthys gen. nov., with two species. The new genus shows a partially fused skull roof, a preopercular bone with a hockey-stick shape and, for the first time in Pholidophoridae, supraneural elements. Most Triassic marine vertebrate clades (fishes and reptiles, Malingichthys included first emerged in the South China Block, with Late Ladinian most showing an important faunal transformation that was strengthened by our last findings. The material here described is about 2 million years older than the previous records for pholidophorids. 

Implantation of cocoa butter reduces egg and hatchling size in Salmo trutta

NARCIS (Netherlands)

Hoogenboom, M. O.; Armstrong, J. D.; Miles, M. S.; Burton, T.; Groothuis, T. G. G.; Metcalfe, N. B.

This study demonstrated that, irrespective of hormone type or dose, administering cocoa butter implants during egg development affected the growth of female brown trout Salmo trutta and reduced the size of their offspring. Cortisol treatment also increased adult mortality. Caution is urged in the

Next generation sequencing yields the complete mitochondrial genome of the largescale mullet, Liza macrolepis (Teleostei: Mugilidae).

Science.gov (United States)

Shen, Kang-Ning; Tsai, Shiou-Yi; Chen, Ching-Hung; Hsiao, Chung-Der; Durand, Jean-Dominique

2016-11-01

In this study, the complete mitogenome sequence of largescale mullet (Teleostei: Mugilidae) has been sequenced by the next-generation sequencing method. The assembled mitogenome, consisting of 16,832 bp, had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 22 transfer RNAs, two ribosomal RNAs genes, and a non-coding control region of D-loop. D-loop which has a length of 1094 bp is located between tRNA-Pro and tRNA-Phe. The overall base composition of largescale mullet is 27.8% for A, 30.1% for C, 16.2% for G, and 25.9% for T. The complete mitogenome may provide essential and important DNA molecular data for further phylogenetic and evolutionary analysis for Mugilidae.

Next generation sequencing yields the complete mitochondrial genome of the Hornlip mullet Plicomugil labiosus (Teleostei: Mugilidae).

Science.gov (United States)

Shen, Kang-Ning; Chen, Ching-Hung; Hsiao, Chung-Der

2016-05-01

In this study, the complete mitogenome sequence of hornlip mullet Plicomugil labiosus (Teleostei: Mugilidae) has been sequenced by next-generation sequencing method. The assembled mitogenome, consisting of 16,829 bp, had the typical vertebrate mitochondrial gene arrangement, including 13 protein coding genes, 22 transfer RNAs, 2 ribosomal RNAs genes and a non-coding control region of D-loop. D-loop contains 1057 bp length is located between tRNA-Pro and tRNA-Phe. The overall base composition of P. labiosus is 28.0% for A, 29.3% for C, 15.5% for G and 27.2% for T. The complete mitogenome may provide essential and important DNA molecular data for further population, phylogenetic and evolutionary analysis for Mugilidae.

An environmental DNA marker for detecting nonnative brown trout (Salmo trutta)

Science.gov (United States)

K. J. Carim; T. M. Wilcox; M. Anderson; D. Lawrence; Michael Young; Kevin McKelvey; Michael Schwartz

2016-01-01

Brown trout (Salmo trutta) are widely introduced in western North America where their presence has led to declines of several native species. To assist conservation efforts aimed at early detection and eradication of this species, we developed a quantitative PCR marker to detect the presence of brown trout DNA in environmental samples. The marker strongly...

Protein degradation systems in the skeletal muscles of parr and smolt Atlantic salmon Salmo salar L. and brown trout Salmo trutta L.

Science.gov (United States)

Kantserova, Nadezda P; Lysenko, Liudmila A; Veselov, Alexey E; Nemova, Nina N

2017-08-01

Although protein degradation limits the rate of muscle growth in fish, the role of proteolytic systems responsible for degrading myofibrillar proteins in skeletal muscle is not well defined. The study herein aims to evaluate the role of calpains (calcium-activated proteases) and proteasomes (ATP-dependent proteases) in mediating muscle protein turnover at different life stages in wild salmonids. Protease activities were estimated in Atlantic salmon (Salmo salar L.) and brown trout (Salmo trutta L.) parr and smolts from the Indera River (Kola Peninsula, Russia). Calpain and proteasome activities in Atlantic salmon skeletal muscles were lower in smolts as compared with parr. Reduced muscle protein degradation accompanying Atlantic salmon parr-smolt transformation appeared to provide intense muscle growth essential for a minimum threshold size achievement that is required for smoltification. Calpain and proteasome activities in brown trout parr and smolts at age 3+ did not significantly differ. However, calpain activity was higher in smolts brown trout 4+ as compared with parr, while proteasome activity was lower. Results suggest that brown trout smoltification does not correspond with intense muscle growth and is more facultative and plastic in comparison with Atlantic salmon smoltification. Obtained data on muscle protein degradation capacity as well as length-weight parameters of fish reflect differences between salmon and trout in growth and smoltification strategies.

The genetic profiles of two salmonid populations from Romania obtained through nuclear markers analysis

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Ramona Nechifor

2017-05-01

Full Text Available The Salmonidae fish family is well represented in Romanian fauna, with a total of six species in the wild and reared in fish farms. Among them, the brown trout (Salmo trutta fario can be found in all major Romanian river basins. However, anthropogenic activities might disrupt salmonids’ habitats, so that inbreeding and genetic isolation might easily occur in the wild populations. We analyzed two wild brown trout populations from rivers targeted by anthropogenic activities, by using nuclear markers and genotyping in order to observe their genetic structure. We analyzed nine microsatellites and we observed their alleles frequencies, number of private alleles, observed and expected heterozygosity, as well as their population structure. The two populations are not in Hardy-Weinberg equilibrium for most of the loci and the inbreeding coefficient for both populations suggests a heterozygote deficit. Further sequencing data are needed in order to have a better view upon their complete genetic structure.

Distribution by origin and sea age of Atlantic salmon (Salmo salar) in the sea around the Faroe Islands based on analysis of historical tag recoveries

DEFF Research Database (Denmark)

Jacobsen, Jan Arge; Hansen, Lars P.; Bakkestuen, Vegar

2012-01-01

Distribution by origin and sea age of Atlantic salmon (Salmo salar) in the sea around the Faroe Islands based on analysis of historical tag recoveries. – ICES Journal of Marine Science, 69: 1598–1608.A database of 2651 tags applied to Atlantic salmon (Salmo salar) smolts in 13 countries...

A microsatellite baseline for genetic stock identification of European Atlantic salmon (Salmo salar L.)

DEFF Research Database (Denmark)

Gilbey, John; Coughlan, Jamie; Wennevik, Vidar

2018-01-01

Atlantic salmon (Salmo salar L.) populations from different river origins mix in the North Atlantic during the marine life stage. To facilitate marine stock identification, we developed a genetic baseline covering the European component of the species' range excluding the Baltic Sea, from the Rus...

Relationship between ecomorphology and trophic segregation in four closely related sympatric fish species (Teleostei, Sciaenidae).

Science.gov (United States)

Blasina, Gabriela; Molina, Juan; Lopez Cazorla, Andrea; Díaz de Astarloa, Juan

This study explores the relationship between ecomorphology and trophic segregation in four closely related sympatric fish species (Teleostei, Sciaenidae) that are known to differ in their trophic habits. Only adult specimens were analyzed: 103 Cynoscion guatucupa, 77 Pogonias cromis, 61 Micropogonias furnieri, and 48 Menticirrhus americanus. The four species presented divergent ecomorphological traits related to swimming agility, prey spotting and capture, and the potential size of prey they were able to swallow. Results suggest that these sciaenid species can partition the food resources, even though they completely overlap in space. Differences in their ecomorphological traits appear to correlate closely with the diet and consequently could explain the trophic differentiation observed. Arguably, these ecomorphological differences play a significant role in the coexistence of the adults of these sympatric fish species. Copyright © 2016 Académie des sciences. Published by Elsevier SAS. All rights reserved.

Genetic structure of European populations of Salmo salar L (Atlantic salmon) inferred from mitochondrial DNA

DEFF Research Database (Denmark)

Eg Nielsen, Einar; Hansen, Michael Møller; Loeschcke, V.

1996-01-01

The genetic relationships between the only natural population of Atlantic salmon (Salmo salar L.) in Denmark and seven other European salmon populations were studied using RFLP analysis of PCR amplified mitochondrial DNA segments. Six different haplotypes were detected by restriction enzyme...

If and when: Intrinsic differences and environmental stressors influence migration in brown trout (Salmo trutta)

DEFF Research Database (Denmark)

Peiman, K. S.; Birnie-Gauvin, Kim; Midwood, J. D.

2017-01-01

Partial migration is a common phenomenon, yet the causes of individual differences in migratory propensity are not well understood. We examined factors that potentially influence timing of migration and migratory propensity in a wild population of juvenile brown trout (Salmo trutta) by combining...

Cytogenetic characterization of the strongly electric Amazonian eel, Electrophorus electricus (Teleostei, Gymnotiformes, from the Brazilian rivers Amazon and Araguaia

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Soraia B.A. Fonteles

2008-01-01

Full Text Available A karyotype analysis of the electric eel, Electrophorus electricus (Teleostei, Gymnotiformes, a strongly electric fish from northern South America, is presented. Two female specimens were analyzed, one from the Amazon River and one from the Araguaia River. The specimens had a chromosomal number of 2n = 52 (42M-SM + 10A. C-bands were present in a centromeric and pericentromeric position on part of the chromosomes; some interstitial C-bands were also present. Heteromorphic nucleolus organizer regions (NORs were detected in two chromosome pairs of the specimen from the Amazon River. The chromosome number and karyotype characteristics are similar to those of other Gymnotidae species. The genera Electrophorus and Gymnotus are positioned as the basal lineages in the Gymnotiformes phylogeny.

Differential effects of mercurial compounds on the electroolfactogram (EOG) of salmon (Salmo salar L.)

DEFF Research Database (Denmark)

Baatrup, E; Døving, K B; Winberg, S

1991-01-01

The effects on the salmon (Salmo salar L.) electroolfactogram (EOG) of the two mercurials, mercuric chloride (HgCl2) and methylmercuric chloride (CH3HgCl), were studied. The EOG responses were evoked by stimulating the olfactory epithelium with 340 microM L-alanine for 10 sec every second minute...

Metales pesados en Trucha Común (Salmo trutta fario.

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LEGORBURU, I., CANTON, L., MILLAN, E., CASADO, A., ALVAREZ, J.

1988-01-01

Full Text Available Se han determinado las concentraciones de metal en hígado branquia y músculo de Trucha común (Salmo trutta fario, procedente de cinco puntos de la cuenca del río Urola. las muestras se analizaron por espectroscopía de absorción atómica, tras su digestión ácida. La distribución de concentraciones es de tipo normal-logarítmico y existe una retención preferente de aluminio, manganeso y zinc en las branquias, mientras el hígado acumula cadmio, hierro y cobre.

Oxidative stress and partial migration in brown trout (Salmo trutta)

DEFF Research Database (Denmark)

Birnie-Gauvin, Kim; Peiman, K. S.; Larsen, Martin Hage

2017-01-01

of oxidative status in migration biology, particularly in fish. Semi-anadromous brown trout (Salmo trutta, Linnaeus 1758) exhibit partial migration, where some individuals smoltify and migrate to sea, and others become stream residents, providing us with an excellent model to investigate the link between...... oxidative stress and migration. Using the brown trout, we obtained blood samples from juveniles from a coastal stream in Denmark in the fall prior to peak seaward migration which occurs in the spring, and assayed for antioxidant capacity (oxygen radical absorbance capacity) and oxidative stress levels...

Proteolysis in salmon ( Salmo salar ) during cold storage : Effects of storage time and smoking process

DEFF Research Database (Denmark)

Lund, K.E.; Nielsen, Henrik Hauch

2001-01-01

Changes in free amino acids (FAAs), small peptides and myofibrillar proteins were investigated in salmon (Salmo salar) muscle stored at OC for up to 23 days and after the stored salmon was smoked. Storage time and smoking process did not increase the formation of FAAs and small peptides indicating...

Genetic monitoring of supportive breeding in brown trout ( Salmo trutta L.), using microsatellite DNA markers

DEFF Research Database (Denmark)

Hansen, Michael Møller; Eg Nielsen, Einar; Ruzzante, D.E.

2000-01-01

loci in samples of wild and hatchery-reared brown trout (Salmo trutta) from three populations subject to supportive breeding. For calibrating statistical procedures, we included two test samples of reared offspring for which the precise number of parent fish was known and a sample from a further wild...

Hyphessobrycon ocasoensis sp. n. (Teleostei, Characidae una nueva especie para el Alto Cauca, Colombia

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García-Alzate, C. A.

2008-12-01

Full Text Available Hyphessobrycon ocasoensis n. sp. (Teleostei, Characidae a new species from the Alto Cauca, Colombia Hyphessobrycon ocasoensis n. sp. (Characiformes, Characidae from heterorhabdus group (Gery, 1977 is described from the upper Cauca River in Colombia. The new species is distinguished from all other known species by the following combination of characters: three unbranched and eight branched fins in the dorsal fin; short maxillary bone with one or no teeth; four small foramens in the maxillary bone, and five in the premaxillary; 5-17 scales with pores in the lateral line, six between the lateral line and anal-fin origin, six between the lateral line and pelvic-fin origin, and nine predorsals; depth of the caudal peduncle has a mean of 16.7% in standard length; interorbital width 50.6% in head; a dark spot on caudal peduncle and a dark lateral band that extends vertically from the dorsal–fin origin to the tips of the middle caudal fin rays. Physical and chemical data of their habitat are included.

Seasonal shift in the effects of predators on juvenile Atlantic salmon (Salmo salar) energetics

Science.gov (United States)

Darren M. Ward; Keith H. Nislow; Carol L. Folt; James Grant

2011-01-01

Predator effects on prey populations are determined by the number of prey consumed and effects on the traits of surviving prey. Yet the effects of predators on prey traits are rarely evaluated in field studies. We measured the effects of predators on energetic traits (consumption and growth rates) of juvenile Atlantic salmon (Salmo salar) in a...

Movements of two strains of radio tagged Atlantic salmon, Salmo salar L., smolts through a reservoir

DEFF Research Database (Denmark)

Aarestrup, Kim; Jepsen, Niels; Rasmusssen, Gorm

1999-01-01

Smolt migration through a shallow and turbid hydro-reservoir in a major Danish river system was investigated using radiotelemetry. Hatchery-reared 1+-year-old Atlantic salmon, Salmo salar L., smolts of equal size from two different non- native strains were radio-tagged and followed during...

Phylogenetic Relationships of Pseudorasbora, Pseudopungtungia, and Pungtungia (Teleostei; Cypriniformes; Gobioninae Inferred from Multiple Nuclear Gene Sequences

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Keun-Yong Kim

2013-01-01

Full Text Available Gobionine species belonging to the genera Pseudorasbora, Pseudopungtungia, and Pungtungia (Teleostei; Cypriniformes; Cyprinidae have been heavily studied because of problems on taxonomy, threats of extinction, invasion, and human health. Nucleotide sequences of three nuclear genes, that is, recombination activating protein gene 1 (rag1, recombination activating gene 2 (rag2, and early growth response 1 gene (egr1, from Pseudorasbora, Pseudopungtungia, and Pungtungia species residing in China, Japan, and Korea, were analyzed to elucidate their intergeneric and interspecific phylogenetic relationships. In the phylogenetic tree inferred from their multiple gene sequences, Pseudorasbora, Pseudopungtungia and Pungtungia species ramified into three phylogenetically distinct clades; the “tenuicorpa” clade composed of Pseudopungtungia tenuicorpa, the “parva” clade composed of all Pseudorasbora species/subspecies, and the “herzi” clade composed of Pseudopungtungia nigra, and Pungtungia herzi. The genus Pseudorasbora was recovered as monophyletic, while the genus Pseudopungtungia was recovered as polyphyletic. Our phylogenetic result implies the unstable taxonomic status of the genus Pseudopungtungia.

Effects of feed quality and quantity on growth, early maturation and smolt development in hatchery-reared landlocked Atlantic salmon Salmo salar.

Science.gov (United States)

Norrgård, J R; Bergman, E; Greenberg, L A; Schmitz, M

2014-10-01

The effects of feed quality and quantity on growth, early male parr maturation and development of smolt characteristics were studied in hatchery-reared landlocked Atlantic salmon Salmo salar. The fish were subjected to two levels of feed rations and two levels of lipid content from first feeding until release in May of their second year. Salmo salar fed high rations, regardless of lipid content, grew the most and those fed low lipid feed with low rations grew the least. In addition, fish fed low lipid feed had lower body lipid levels than fish fed high lipid feed. Salmo salar from all treatments showed some reduction in condition factor (K) and lipid levels during their second spring. Smolt status was evaluated using both physiological and morphological variables. These results, based on gill Na(+) , K(+) -ATPase (NKA) enzyme activity, saltwater tolerance challenges and visual assessments, were consistent with each other, showing that S. salar from all treatments, except the treatment in which the fish were fed low rations with low lipid content, exhibited characteristics associated with smolting at 2 years of age. Sexually mature male parr from the high ration, high lipid content treatment were also subjected to saltwater challenge tests, and were found to be unable to regulate plasma sodium levels. The proportion of sexually mature male parr was reduced when the fish were fed low feed rations, but was not affected by the lipid content of the feed. Salmo salar fed low rations with low lipid content exhibited the highest degree of severe fin erosion. © 2014 The Fisheries Society of the British Isles.

Application of heteroduplex analysis for detecting variation within the growth hormone 2 gene in Salmo trutta L. (brown trout).

Science.gov (United States)

Gross, R; Nilsson, J

1995-03-01

A new method to detect variation at a single copy nuclear gene in brown trout, Salmo trutta L., is provided. The technique entails (i) selective gene amplification by the polymerase chain reaction (PCR), (ii) digestion of amplification products by restriction endonucleases to obtain fragments of suitable size, (iii) hybridization with heterologous DNA followed by denaturation and reannealing to obtain heteroduplex molecules, and (iv) screening for variation in polyacrylamide gels. Variation was studied within a growth hormone 2 gene 1489 bp segment and polymorphism was detected in two HinfI-digested fragments. Formation of different heteroduplex patterns in experimental mixtures of digested amplification products from brown trout and Atlantic salmon, Salmo salar L., allowed us to determine the genotype of the brown trout. Polymorphism was observed in four out of six studied populations.

Growth and Movement in Brown Trout (Salmo trutta) in two Norwegian Rivers

OpenAIRE

Skjellevik, Stine Marie

2012-01-01

In the present study, using stream-dwelling brown trout (Salmo trutta) as a model species, movement through the summer and autumn in two large Norwegian rivers, River Glomma and River Gudbrandsdalslågen, was observed. In addition fish from each river were sampled for age and growth analysis. The aim of the study was to test for which individual characteristics (sex, body mass, body condition factor, tagging site and cohort) that influenced movement and to test for correlations between grow...

A free-living amoeba with unusual pattern of mitochondrial structure isolated from Atlantic salmon, Salmo salar L

Czech Academy of Sciences Publication Activity Database

Dyková, Iva; Veverková, Marie; Fiala, Ivan; Macháčková, Blanka

2002-01-01

Roč. 41, - (2002), s. 415-419 ISSN 0065-1583 R&D Projects: GA AV ČR IAA6022202 Institutional research plan: CEZ:AV0Z6022909 Keywords : free-living amoeba * mitochondrial cristae * Salmo salar Subject RIV: EA - Cell Biology Impact factor: 0.446, year: 2002

Atividade de amilase em quimo de três espécies tropicais de peixes teleostei de água doce Amylase activity in the chyme of three teleostei freshwater fish

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José Teixeira de Seixas Filho

1999-01-01

Full Text Available O objetivo deste trabalho foi determinar a atividade de amilase no quimo presente nos intestinos médio e posterior, ou reto, em três espécies tropicais de peixes Teleostei de água doce: piracanjuba, Brycon orbignyanus (Valenciennes, 1849, piau, Leporinus friderici (Bloch, 1794, onívoros, e surubim, Pseudoplatystoma coruscans (Agassiz, 1829, preferencialmente carnívoro, visando fornecer referência à nutrição para o ajuste da alimentação artificial. As atividades de amilase foram determinadas usando-se kit BIOCLIN com metodologia modificada por CARAWAY (1959. Os resultados monstraram atividade específica média (2106,33 UA/mg para amilase do piracanjuba e foram 91,74% menor em comparação ao piau (25.488,14 UA/mg, ambos de hábito alimentar onívoro, enquanto a atividade específica da amilase para o piracanjuba foi 89,06% menor em relação ao surubim (19.246,80 UA/mg, carnívoro, o qual apresentou atividade específica da amilase 24,49% menor em relação à do piau. Os dados sugerem que a grande diferença da atividade específica de amilase entre o piau e o piracanjuba possui ligação com sua morfometria e o complexo arranjo das pregas da mucosa dos intestinos médio e posterior. Além disso, a atividade de amilase do surubim indica possibilidade de uso de ração contendo carboidratos, porém estudos adicionais são necessários para a avaliação do comportamento dessas espécies na alimentação artificial.The objective of this work was to determine the amylase activity in the chyme present in the medium and posterior intestines or in the rectum of three tropical freshwater Teleostei species: piracanjuba, Brycon orbignyanus (Valenciennes, 1849, piau, Leporinus friderici (Bloch, 1974, omnivorous, and surubim, Pseudoplatystoma coruscans (Agassiz, 1829, preferably carnivorous, aiming to provide nutritional reference data for the adjustment of the artificial feeding systems. The amylase activity was determined by the use of

Systemic granuloma observed in Atlantic salmon Salmo salar raised to market size in a freshwater recirculation aquaculture system

Science.gov (United States)

Systemic granuloma was observed in sampled adult Atlantic salmon Salmo salar raised to harvest size in a freshwater recirculation aquaculture system. The prevalence of this condition was estimated at 10-20% of the population, with affected individuals grossly demonstrating pathology in varying degre...

The physiological basis of the migration continuum in brown trout ( Salmo trutta)

DEFF Research Database (Denmark)

Boel, Mikkel; Aarestrup, Kim; Baktoft, Henrik

2014-01-01

Partial migration is common in many animal taxa; however, the physiological variation underpinning migration strategies remains poorly understood. Among salmonid fishes, brown trout (Salmo trutta) is one of the species that exhibits the most complex variation in sympatric migration strategies......, expressed as a migration continuum, ranging from residency to anadromy. In looking at brown trout, our objective with this study was to test the hypothesis that variation in migration strategies is underpinned by physiological variation. Prior to migration, physiological samples were taken from fish...... in brown trout....

Next generation sequencing yields the complete mitochondrial genome of the flathead mullet, Mugil cephalus cryptic species NWP2 (Teleostei: Mugilidae).

Science.gov (United States)

Shen, Kang-Ning; Yen, Ta-Chi; Chen, Ching-Hung; Li, Huei-Ying; Chen, Pei-Lung; Hsiao, Chung-Der

2016-05-01

In this study, the complete mitogenome sequence of Northwestern Pacific 2 (NWP2) cryptic species of flathead mullet, Mugil cephalus (Teleostei: Mugilidae) has been amplified by long-range PCR and sequenced by next-generation sequencing method. The assembled mitogenome, consisting of 16,686 bp, had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs genes and a non-coding control region of D-loop. D-loop was 909 bp length and was located between tRNA-Pro and tRNA-Phe. The overall base composition of NWP2 M. cephalus was 28.4% for A, 29.8% for C, 26.5% for T and 15.3% for G. The complete mitogenome may provide essential and important DNA molecular data for further phylogenetic and evolutionary analysis for flathead mullet species complex.

Quantification of vitellogenin in Atlantic salmon (Salmo salar) plasma by radioimmunoassay

International Nuclear Information System (INIS)

Idler, D.R.; Hwang, S.J.; Crim, L.W.

1979-01-01

An antibody prepared against salmon egg yolk proteins has been used to quantify Atlantic salmon (Salmo salar) plasma vitellogenin using radioimmunoassay. A low molecular weight fraction isolated from salmon egg yolk was used for radioiodination and as standard solution because plasma vitellogenin could not be iodinated successfully. Parallelism of the egg yolk standard to displacement given by a fraction isolated from vitellogenic salmon plasma and dilutions of plasma samples allowed the assay to be used to evaluate the state of gonadal development of migrating females several months in advance of spawning and for sexing relatively immature salmon. (author)

Can sea trout Salmo trutta compromise successful eradication of Gyrodactylus salaris by hiding from CFT Legumin (rotenone) treatments?

DEFF Research Database (Denmark)

Davidsen, J. G.; Thorstad, E. B.; Baktoft, H.

2013-01-01

In this study, 34 anadromous brown trout (sea trout) Salmo trutta were equipped with acoustic transmitters in order to examine whether they performed avoidance behaviour in response to a CFT Legumin (rotenone) treatment in the Norwegian River Vefsna. Migratory behaviour of the S. trutta was monit...

The volitional travel speed varies with reproductive state in mature female brown trout Salmo trutta

DEFF Research Database (Denmark)

Svendsen, Jon Christian; Aarestrup, Kim; Dolby, Jes

2009-01-01

This study tested the effect of reproduction on the volitional travel speed of mature female brown trout Salmo trutta L. The downstream travel speed in the pre-spawning state was 0·25 m s−1 (95% CI : 0·19, 0·34) while it increased significantly to 0·65 m s−1 (95% CI: 0·49, 0·87) in the post...

Next-generation sequencing yields the complete mitochondrial genome of the flathead mullet, Mugil cephalus cryptic species in East Australia (Teleostei: Mugilidae).

Science.gov (United States)

Shen, Kang-Ning; Chen, Ching-Hung; Hsiao, Chung-Der; Durand, Jean-Dominique

2016-09-01

In this study, the complete mitogenome sequence of a cryptic species from East Australia (Mugil sp. H) belonging to the worldwide Mugil cephalus species complex (Teleostei: Mugilidae) has been sequenced by next-generation sequencing method. The assembled mitogenome, consisting of 16,845 bp, had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs genes and a non-coding control region of D-loop. D-loop consists of 1067 bp length, and is located between tRNA-Pro and tRNA-Phe. The overall base composition of East Australia M. cephalus is 28.4% for A, 29.3% for C, 15.4% for G and 26.9% for T. The complete mitogenome may provide essential and important DNA molecular data for further phylogenetic and evolutionary analysis for flathead mullet species complex.

Two new species of Monogenea (Platyhelminthes: Cercomeridea parasitic on Chaetodipterus faber (Teleostei: Ephippidae from the Brazilian coastal zone

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A. D. Cezar

1999-09-01

Full Text Available Metazoan parasites were extracted for 110 Chaetodipterus faber (Broussonet, 1782 (Teleostei: Ephippidae specimens from the coastal zone of the State of Rio de Janeiro, Brazil (nearly 21-23° S, 41-45° W. Two new species of monogeneans belonging to genera Sprostoniella and Parancylodiscoides are described and illustrated. The new species of Sprostoniella, differ from S. multitestis, the only known species of the genus, by: 1. the arrangement of septa (with 17 septa, two of them bifid and two incomplet in the new species; 17 septa, two of them trifid in S. multitestis. 2. the new species showed two central loculi, while S. multitestis only one, and 3. the first pair of anchors of the new species is small and poorly developed, while in S. multitestis is well developed and strong. The new species of Parancylodiscoides differs from P. chaetodipteri, the only known species of the genus, by: 1. the testis shape (bilobated in the new species, not bilobated in P. chaetodipteri, and 2. by the presence of accessory prostatic reservoir at the copulatory organ base (absent in P. chaetodipteri.Se extrajeron metazoos parásitos de 110 Chaetodipterus faber (Broussonet, 1782 (Teleostei: Ephippidae del litoral del Estado de Rio de Janeiro, Brasil (aprox. 21-23° S, 41-45° W. Se describe e ilustra dos nuevas especies de monogéneos de los géneros Sprostoniella y Parancylodiscoides. La nueva especie de Sprostoniella difiere de S. multitestis, la otra especie del género, por 1. la disposición de los septos (con 17 septos, dos de ellos bífidos y dos incompletos en la nueva especie; 17 septos, dos de ellos trífidos en S. multitestis, 2. la nueva especie muestra dos lóculos centrales, mientras S. multitestis sólo uno, y 3. el primer par de ganchos en la nueva especie es pequeño y poco desarrollado, mientras que en S. multitestis es robusto y bien desarrollado. La nueva especie de Parancylodiscoides difiere de P. chaetodipteri, la otra especie del género, por

Sulphated glycosaminoglycans and proteoglycans in the developing vertebral column of juvenile Atlantic salmon (Salmo salar)

OpenAIRE

Hannesson, Kirsten O.; Ytteborg, Elisabeth; Takle, Harald; Enersen, Grethe; B?verfjord, Grete; Pedersen, Mona E.

2015-01-01

In the present study, the distribution of sulphated glycosaminoglycans (GAGs) in the developing vertebral column of Atlantic salmon (Salmo salar) at 700, 900, 1100 and 1400?d? was examined by light microscopy. The mineralization pattern was outlined by Alizarin red S and soft structures by Alcian blue. The temporal and spatial distribution patterns of different types of GAGs: chondroitin-4-sulphate/dermatan sulphate, chondroitin-6-sulphate, chondroitin-0-sulphate and keratan sulphate were add...

Description of a bacterium associated with redmouth disease of rainbow trout (Salmo gairdneri)

Science.gov (United States)

Ross, A.J.; Rucker, R.R.; Ewing, W.H.

1966-01-01

A description was given of a gram-negative, peritrichously flagellated, fermentative bacterium that was isolated on numerous occasions from kidney tissues of rainbow trout (Salmo gairdneri) afflicted with redmouth disease. Although the bacteria apparently were members of the family Enterobacteriaceae, it was impossible to determine their taxonomic position within the family with certainty. Hence it was recommended that their taxonomic position remain sub judice for the present. As a temporary designation RM bacterium was used. Redmouth disease was transmitted from infected to normal fish through the medium of water.

The effects of ozonation on select waterborne steroid hormones in recirculation aquaculture systems containing sexually mature Atlantic salmon Salmo salar

Science.gov (United States)

A controlled 3-month study was conducted in 6 replicated water recirculation aquaculture systems (RAS) containing a mixture of sexually mature and immature Atlantic salmon Salmo salar to determine whether water ozonation is associated with a reduction in waterborne hormones. Post-smolt Atlantic salm...

Regulation of Na+/K+-ATPase activity by nitric oxide in the kidney and gill of the brown trout (Salmo trutta)

DEFF Research Database (Denmark)

Tipsmark, Christian K; Madsen, Steffen S

2003-01-01

In teleost fish, successful osmoregulation involves controlled ion transport mechanisms in kidney and gill epithelia. In this study, the effect of nitric oxide (NO) on Na(+)/K(+)-ATPase was investigated in vitro in these two tissues in brown trout (Salmo trutta) acclimated to freshwater...

Two new species of Hypostomus Lacépède (Teleostei: Loricariidae from the upper rio Paraná basin, Central Brazil

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Cláudio H. Zawadzki

Full Text Available Two new species of Hypostomus Lacépède (Teleostei: Loricariidae from the rio Paranaíba and rio Grande basins, both in the upper rio Paraná basin, central Brazil, are described herein. One of them is distinguished from all congeners, except H. albopunctatus, by having the pectoral-fin spine length equal to or smaller than the pelvic-fin spine. From H. albopunctatus, it is distinguished by having round dark spots (vs. pale on body and fins. The second species is distinguished from all congeners, except H. multidens and H. ternetzi, by having more than 115 teeth (vs. less than 109 per ramus on dentary and premaxilla. It is distinguished most readily from H. ternetzi by having teeth with two symmetrical (vs. asymmetrical cusps. It is distinguished from H. multidens by having round dark spots (vs. pale over body and fins.

Effect of radioactive iron /sup 59/Fe on the embryogeny of sea-trout (Salmo trutta L. )

Energy Technology Data Exchange (ETDEWEB)

Dabrowski, K; Tucholski, S; Czarnocki, J

1975-01-01

Accumulation and diffusion of /sup 59/Fe in the eggs of Salmo trutta L. were observed under laboratory conditions. The dynamics of iron budget in the egg with developing embryo were determined. Differences were found in the accumulation and elimination of iron depending on the stage of the embryos development in the eggs at the time when they were put into the radionuclide solution and on the strength of its concentration.

Phosphorus flux due to Atlantic salmon (Salmo salar) in an oligotrophic upland stream: effects of management and demography

Science.gov (United States)

Keith H. Nislow; John D. Armstrong; Simon. McKelvey

2004-01-01

Little is known concerning the role of Atlantic salmon (Salmo salar) in the transport of nutrients to and from river systems. We used demographic data from the River Bran, an oligotrophic river in Scotland, UK, to construct a budget for the transport of phosphorus (P) and applied it to investigate the effects of management strategies and demographic...

Allelic frequencies of two microsatellite loci in four populations of brown trout (Salmo trutta)

OpenAIRE

EDIT VARDHAMI; ANILA HODA; ADIOLA BIBA; MANUELA GUALTIERI; MASSIMO MECATTI; AGIM REXHEPI

2014-01-01

Two microsatellite loci, Str60Inra and Ssa197, were PCR amplified on 30 individuals for each populations of brown trout (Salmo trutta). A total of 120 individuals were selected from rivers of the Florence province (Italy), Valbona and Cen (Albania), Lepenci (Kosovo). There were identified 32 different alleles for Str60Inra and 41 for the locus Ssa197. Mean number of alleles ranged from 9 (Cen) to 20.5 (Florence). The mean observed and expected heterosygosities values were 0.329 and 0.755, res...

Spatially and temporally fluctuating selection at non-MHC immune genes: evidence from TAP polymorphism in populations of brown trout ( Salmo trutta , L.)

DEFF Research Database (Denmark)

Jensen, L.F.; Hansen, Michael Møller; Mensberg, Karen-Lise Dons

2008-01-01

Temporal samples of Danish brown trout (Salmo trutta) from populations representing varying geographical scales were analysed using eight putatively neutral microsatellite loci and two microsatellite loci embedded in TAP genes (Transporter associated with Antigen Processing). These genes encode m...

Fate of 7,12-dimethylbenz(a)anthracene in rainbow trout, Salmo gairdneri

International Nuclear Information System (INIS)

Schnitz, A.R.; Squibb, K.S.; O'Connor, J.M.

1987-01-01

Polycyclic aromatic hydrocarbons (PAH) are contaminants of surface waters and sediments, especially near urban centers. Although aquatic biota accumulate PAHs from environmental sources, metabolism may be rapid, and biota sampled from contaminated areas often have concentrations lower than might be estimated from bioconcentration factors. In some cases PAH metabolism by aquatic biota may create reactive intermediates, some of which have been related to chronic effects in fishes. This report describes the fate and distribution of 7,12-dimethylbenz(a)anthracene (DMBA) after oral administration to rainbows trout (Salmo gairdneri). Emphasis has been placed on the disposition of DMBA among tissues and on DMBA transformation in the hepatobiliary system

Physiological effects of simultaneous, abrupt seawater entry and sea lice (Lepeophtheirus salmonis) infestation of wild, sea-run brown trout (Salmo trutta) smolts

NARCIS (Netherlands)

Wells, A.; Grierson, C.E.; MacKenzie, M.A.; Russon, I.; Middlemiss, C.; Bjorn, P.A.; Finstad, B.; Wendelaar Bonga, S.E.; Todd, C.D.; Hazon, N.

2006-01-01

For wild, sea-run brown trout (Salmo trutta) smolts, the physiological consequences of abrupt transfer to seawater and simultaneous challenge with copepodid larvae of the sea louse, Lepeophtheirus salmonis (Kr�yer, 1837), were investigated in the laboratory. Analysis of osmoregulatory, metabolic,

Evidence of Atlantic salmon Salmo salar fry movement between fresh water and a brackish environment.

Science.gov (United States)

Taal, I; Rohtla, M; Saks, L; Svirgsden, R; Kesler, M; Matetski, L; Vetemaa, M

2017-08-01

This study reports descent of Atlantic salmon Salmo salar fry from their natal streams to brackish waters of the Baltic Sea and their use of this environment as an alternative rearing habitat before ascending back to freshwater streams. To the authors' knowledge, residency in a brackish environment has not previously been demonstrated in S. salar fry. Recruitment success and evolutionary significance of this alternative life-history strategy are presently not known. © 2017 The Fisheries Society of the British Isles.

Routes and survival of anadromous brown trout Salmo trutta L. post-smolts during early marine migration through a Danish fjord system

DEFF Research Database (Denmark)

Kristensen, Martin Lykke; Birnie-Gauvin, Kim; Aarestrup, Kim

2018-01-01

We examined the survival and progression rates of 101 anadromous brown trout Salmo trutta L. post-smolts from two Danish river systems, Karup and Simested, with acoustic telemetry as they migrated through a large Danish fjord system (the Limfjord). No fish were documented to residualize permanently...

Heterochrony in fringeheads (Neoclinus) and amplification of an extraordinary aggressive display in the Sarcastic Fringehead (Teleostei: Blenniiformes).

Science.gov (United States)

Hongjamrassilp, Watcharapong; Summers, Adam P; Hastings, Philip A

2018-05-01

The Sarcastic Fringehead (Neoclinus blanchardi, Teleostei) exhibits an extreme version of a common aggressive display, the "gaping display," in which an open mouth is presented toward an opponent. Males of this species have extremely long jaws that extend posteriorly well past the posterior margin of the head and are flared laterally during the gaping display. In this study, we explored morphological traits related to this extraordinary display in this and related species of blennies. Morphological modifications include enlargement of the buccopalatal membrane, elongation of the maxilla via an uncalcified posterior extension, and evolution of a novel hinge between the anterior maxilla and lacrimal bones permitting lateral movement of the upper jaw. Geometric morphometry using the truss network system, thin-plate spline, and PCA of three closely related species of Neoclinus indicate that the elongate maxilla of N. blanchardi most likely evolved via acceleration (faster growth compared to outgroups) and hypermorphosis (continued growth to a larger body size), both forms of peramorphic heterochrony. Coloration and fluorescence of the buccopalatal membrane may also serve to amplify the extraordinary gaping display of the Sarcastic Fringehead. © 2018 Wiley Periodicals, Inc.

Genetic Diversity and Hybridisation between Native and Introduced Salmonidae Fishes in a Swedish Alpine Lake.

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Leanne Faulks

Full Text Available Understanding the processes underlying diversification can aid in formulating appropriate conservation management plans that help maintain the evolutionary potential of taxa, particularly under human-induced activities and climate change. Here we assessed the microsatellite genetic diversity and structure of three salmonid species, two native (Arctic charr, Salvelinus alpinus and brown trout, Salmo trutta and one introduced (brook charr, Salvelinus fontinalis, from an alpine lake in sub-arctic Sweden, Lake Ånn. The genetic diversity of the three species was similar and sufficiently high from a conservation genetics perspective: corrected total heterozygosity, H'T = 0.54, 0.66, 0.60 and allelic richness, AR = 4.93, 5.53 and 5.26 for Arctic charr, brown trout and brook charr, respectively. There were indications of elevated inbreeding coefficients in brown trout (GIS = 0.144 and brook charr (GIS = 0.129 although sibling relationships were likely a confounding factor, as a high proportion of siblings were observed in all species within and among sampling locations. Overall genetic structure differed between species, Fst = 0.01, 0.02 and 0.04 in Arctic charr, brown trout and brook charr respectively, and there was differentiation at only a few specific locations. There was clear evidence of hybridisation between the native Arctic charr and the introduced brook charr, with 6% of individuals being hybrids, all of which were sampled in tributary streams. The ecological and evolutionary consequences of the observed hybridisation are priorities for further research and the conservation of the evolutionary potential of native salmonid species.

A Polyprotein-Expressing Salmonid Alphavirus Replicon Induces Modest Protection in Atlantic Salmon (Salmo Salar Against Infectious Pancreatic Necrosis

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Azila Abdullah

2015-01-01

Full Text Available Vaccination is an important strategy for the control and prevention of infectious pancreatic necrosis (IPN in farmed Atlantic salmon (Salmo salar in the post-smolt stage in sea-water. In this study, a heterologous gene expression system, based on a replicon construct of salmonid alphavirus (SAV, was used for in vitro and in vivo expression of IPN virus proteins. The large open reading frame of segment A, encoding the polyprotein NH2-pVP2-VP4-VP3-COOH, as well as pVP2, were cloned and expressed by the SAV replicon in Chinook salmon embryo cells (CHSE-214 and epithelioma papulosum cyprini (EPC cells. The replicon constructs pSAV/polyprotein (pSAV/PP and pSAV/pVP2 were used to immunize Atlantic salmon (Salmo salar by a single intramuscular injection and tested in a subsequent IPN virus (IPNV challenge trial. A low to moderate protection against IPN was observed in fish immunized with the replicon vaccine that encoded the pSAV/PP, while the pSAV/pVP2 construct was not found to induce protection.

Growth evaluation of atlantic salmon (Salmo salar) raised in seawater or freshwater and fed either fishmeal based on marine-free diets

Science.gov (United States)

A forty week feeding study was conducted with Atlantic salmon (Salmo salar) smolts in two recirculating aquaculture systems. Twelve salmon (average initial weight 117 g; initial density 9.4 kg/m3) were stocked per tank. Two identical systems were used and contained either freshwater (0 ppt) or sea...

Growth evaluation of Atlantic Salmon (Salmo salar) raised in seawater or freshwater and fed either fishmeal based or marine-free diets

Science.gov (United States)

A forty week feeding study was conducted with Atlantic salmon (Salmo salar) smolts in two recirculating aquaculture systems. Two identical systems were used and contained either freshwater (0 ppt) or seawater (about 30 ppt). Fish were fed one of two diets, a control diet containing fishmeal and fi...

Baking Reduces Prostaglandin, Resolvin, and Hydroxy-Fatty Acid Content of Farm-Raised Atlantic Salmon (Salmo salar)

OpenAIRE

Raatz, Susan K.; Golovko, Mikhail Y.; Brose, Stephen A.; Rosenberger, Thad A.; Burr, Gary S.; Wolters, William R.; Picklo, Matthew J.

2011-01-01

Consumption of seafood enriched in n-3 polyunsaturated fatty acids (PUFA) is associated with a decreased risk of cardiovascular disease. Several n-3 oxidation products from eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3) have known protective effects in the vasculature. It is not known whether consumption of cooked seafood enriched in n-3 PUFA causes appreciable consumption of lipid oxidation products. We tested the hypothesis that baking Atlantic salmon (Salmo sa...

Trans-generational maternal effect: temperature influences egg size of the offspring in Atlantic salmon Salmo salar.

Science.gov (United States)

Jonsson, B; Jonsson, N

2016-08-01

Effect of increased temperature during egg maturation on the mass of single eggs produced by the offspring was investigated experimentally in Atlantic salmon Salmo salar. Mass of eggs produced by next-generation females was larger when their mothers experienced warmer water during the last two months of egg maturation, relative to those that experienced unheated river water. There was no similar trans-generational paternal effect on offspring egg mass. © 2016 The Fisheries Society of the British Isles.

Genetic structure and demographic history of brown trout ( Salmo trutta ) populations from the southern Balkans

DEFF Research Database (Denmark)

Apostolidis, A.P.; Madeira, M.J.; Hansen, Michael Møller

2008-01-01

1. The present study was designed to characterize the genetic structure of brown trout (Salmo trutta) populations from the southern Balkans and to assess the spread of non-native strains and their introgression into native trout gene pools. We analysed polymorphism at nine microsatellite loci...... in seven supposedly non-admixed and three stocked brown trout populations. 2. The analyses confirmed the absence of immigration and extraordinarily strong genetic differentiation among the seven non-introgressed populations in parallel with low levels of intrapopulation genetic variability. In contrast...

Fate of Tetracapsuloides bryosalmonae (Myxozoa) after infection of brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss

OpenAIRE

Kumar, Gokhlesh; Abd-Elfattah, Ahmed; Saleh, Mona; El-Matbouli, Mansour

2013-01-01

Tetracapsuloides bryosalmonae (Myxozoa) is the causative agent of proliferative kidney disease in salmonids. We assessed differences in intensity of T. bryosalmonae infection between brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss from the clinical phase of infection onwards. Specific pathogen-free fish were exposed to T. bryosalmonae spores under controlled laboratory conditions and sampled at 6, 8, 10, 12, 14, and 17 wk post exposure (wpe), and the transmission of T. bryosalm...

Relationship between gill Na+,K+-ATPase activity and downstream movement in domesticated and first-generation offspring of wild anadromous brown trout ( Salmo trutta )

DEFF Research Database (Denmark)

Aarestrup, Kim; Nielsen, C.; Madsen, S.S.

2000-01-01

The relationship between smolt status and downstream movement following release was investigated in two stocks of hatchery- reared anadromous brown trout (Salmo trutta). Yearlings from a domesticated stock (DS) and first-generation offspring (F1) of wild anadromous trout were held under identical...

Reliable collection of Caspian brown trout (Salmo trutta caspius) sperm using a catheter.

Science.gov (United States)

Aramli, M S; Golshahi, K; Banan, A; Sotoudeh, E

2016-10-01

The traditional stripping procedure for collecting fish semen is associated with the risk of urine contamination, which may significantly affect semen quality and quantity. The use of a catheter as an alternative method for semen collection may overcome this problem. Therefore, this study compared Caspian brown trout (Salmo trutta caspius) semen parameters (i.e. sperm density, seminal plasma osmolality, motility parameters of spermatozoa analysed using computer-assisted sperm analysis and fertility) between the traditional stripping method and the use of a catheter. All parameter values of the semen collected with a catheter were significantly higher (p brown trout sperm. © 2016 Blackwell Verlag GmbH.

Selenium-induced autometallographic demonstration of endogenous zinc in organs of the rainbow trout, Salmo gairdneri

DEFF Research Database (Denmark)

Baatrup, E

1989-01-01

, the intestine, and the gills, whereas, no such grains were found in preparations from fish having received 1 ppm Se. The use of selenium for the histochemical demonstration of endogenous zinc versus exogenous metals is discussed. Also, consideration is given to the question of which part of the total tissue......Autometallographic (AMG) silver enhancement of endogenous zinc was studied in seven organs of the rainbow trout Salmo gairdneri. Groups of trout were injected intraperitoneally with sodium selenite in doses ranging from 0.08 to 25 ppm, administered 1 h before being killed. The concentration...

ARTIFICIAL BREEDING OF NERETVA SOFTMOUTH TROUT (Salmo obtusirostris Oxyrhincus Heckel, 1851

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Dževad Handžar

2015-06-01

Full Text Available The paper presents an artificial breeding of softmouth trout (Salmo obtusirostris oxyrhynchus, which is one of the endemic species of fish Neretva basin and which is on the Red List of the International Union for Conservation of Nature (IUCN as endangered species facing extinction. Production of fry softmouth trout intended for restocking is very complex and complicated process, and in this paper, which is based on long experience in artificial breeding softmouth trout, we want to contribute to the conservation and breeding of native salmonid fish and aquaculture development of BiH. The paper describes the production technology and production phase, diet and food as well as the application of preventive and therapeutic measures in production. Key word - softmouth trout, artificial breeding, preventive and therapeutic measures

Dactylogyrid monogeneans parasitising Cyphocharax voga (Hensel) (Teleostei: Curimatidae) from the Pampas region, Argentina: new and previously described species.

Science.gov (United States)

Rossin, María Alejandra; Timi, Juan Tomás

2016-09-01

Most studies on dactylogyrid monogeneans in Argentina have been carried out during 1980s and 1990s. Many of these species have been later synonymised and other remain under a confusing taxonomic status, particularly those parasitising Cyphocharax voga (Hensel) (Teleostei: Curimatidae). In order to clarify the identity of dactylogyrids, new material was collected from fishes in Lake Chascomús, Buenos Aires Province, Argentina. A total of four species was found in the gills of C. voga. Two known species, Curvianchoratus singularis (Suriano, 1980) Suriano, 1986 and Palombitrema triangulum (Suriano, 1981) Suriano, 1997, are redescribed and their generic and specific status discussed, and two new species are described. Urocleidoides surianoae n. sp. can be distinguished from its congeners by having an anterior medial projection in the ventral bar and a laminar ligament connecting the base of the male copulatory organ and accessory piece. Annulotrematoides bonaerensis n. sp. differs from its congeners principally by having a ventral bar with an anterior medial projection. The diversity of dactylogyrids harboured by C. voga indicates the need of further studies in the Pampas region, which will provide interesting and valuable sources of evidence for future zoogeographical and evolutionary research on dactylogyrids in the Neotropics.

Identification and molecular docking study of novel angiotensin-converting enzyme inhibitory peptides from Salmo salar using in silico methods.

Science.gov (United States)

Yu, Zhipeng; Chen, Yang; Zhao, Wenzhu; Li, Jianrong; Liu, Jingbo; Chen, Feng

2018-01-25

In order to circumvent some challenges of the classical approach, the in silico method has been applied to the discovery of angiotensin-converting enzyme (ACE) inhibitory peptides from food proteins. In this study, some convenient and efficient in silico tools were utilized to identify novel ACE inhibitory peptides from Salmo salar. Collagen from Salmo salar was digested in silico into hundreds of peptides. Results revealed that tetrapeptides PGAR and IGPR showed potent ACE inhibitory activity, with IC 50 values of 0.598 ± 0.12 and 0.43 ± 0.09 mmol L -1 , respectively. The molecular docking result showed that PGAR and IGPR interact with ACE mostly via hydrogen bonds and attractive charge. Peptide IGPR interacts with Zn + at the ACE active site, showing high inhibitory activity. Interaction with Zn + in ACE may lead to higher inhibitory activity of peptides, and Pi interactions may promote the effect of peptides on ACE. The in silico method can be an effective method to predict potent ACE inhibitory peptides from food proteins. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

[Ontogenetic Mechanisms of Explosive Morphological Divergence in the Lake Tana (Ethiopia) Species Flock of Large African Barbs (Labeobarbus; Cyprinidae; Teleostei)].

Science.gov (United States)

Shkila, F N; Lazebny, O E; Kapitanova, D V; Abdissa, Belay; Borisov, V B; Smirnov, S V

2015-01-01

Species flock of Lake Tana (Ethiopia) large African barbs (Labeobarbus; Cyprinidae; Teleostei) was studied as a model system for investigating ontogenetic mechanisms of the explosive morphological divergence often accompanying sympatric speciation in bony fishes. Comparative morphological analysis carried out with the use ofgeometric morphometric techniques revealed quantitative differences in the head shapes of species under study. Comparative analysis of skull development revealed significant interspecies differences in the temporal characteristics of craniogenesis in these species. These two lines of evidence suggest that heterochronies in craniogenesis underlie divergence in the head shapes of adult Tana barbs. This prediction was verified via experimental changes of temporal characteristics of craniogenesis in L. intermedius, a putative ancestor for the Lake Tana species flock. For this aim, timing and rate of skull development were changed by artificial manipulation of thyroid hormone levels. In sum, it was shown that it is heterochronies that underlie an explosive morphological divergence of the Lake Tana barbs species flock. Our findings together with those reported in the literature suggest variability in the activity of the hypothalamic-pituitary-thyroid axis to contribute to these heterochronies.

Aluminum exposure impacts brain plasticity and behavior in Atlantic salmon (Salmo salar).

Science.gov (United States)

Grassie, C; Braithwaite, V A; Nilsson, J; Nilsen, T O; Teien, H-C; Handeland, S O; Stefansson, S O; Tronci, V; Gorissen, M; Flik, G; Ebbesson, L O E

2013-08-15

Aluminum (Al) toxicity occurs frequently in natural aquatic ecosystems as a result of acid deposition and natural weathering processes. Detrimental effects of Al toxicity on aquatic organisms are well known and can have consequences for survival. Fish exposed to Al in low pH waters will experience physiological and neuroendocrine changes that disrupt homeostasis and alter behavior. To investigate the effects of Al exposure on both the brain and behavior, Atlantic salmon (Salmo salar) kept in water treated with Al (pH 5.7, 0.37±0.04 μmol 1(-1) Al) for 2 weeks were compared with fish kept in under control conditions (pH 6.7, salmon, and may impair the ability to cope with new environments.

Blood ph and mortality of rainbow trout (Salmo gairdnerii) and sockeye salmon (Oncorhynchus nerka)

Energy Technology Data Exchange (ETDEWEB)

Jonas, R E.E.; Sehdev, H S; Tomlinson, N

1972-01-01

Rainbow trout (Salmo gairdnerii) under light anaesthesia with MS 222 (Tricaine methanesulphonate) died when their blood pH was lowered into the range of 6.8 to 6.9 by injection of either lactic acid or hydrochloric acid. When injection of the same quantities of either acid did not lower the blood pH into this range, fatalities did not result (one exception in 56 fish injected). The injection of much larger quantities of lactate of chloride ions in the form of sodium salts did not cause fatalities. Very limited date for sockeye salmon (Oncorhynchus nerka) suggest a similar association between blood pH and mortality for this species.

Temperature selection of juvenile Atlantic salmon (Salmo salar) as influenced by various toxic substances

Energy Technology Data Exchange (ETDEWEB)

Peterson, R H

1976-08-01

Previous exposure to sodium pentachlorophenate (NaPCP), Guthion, malathion, Dursban, and Dibrom lowered the preferred temperature for juvenile Atlantic salmon (Salmo salar) tested in a horizontal temperature gradient. Lindane, CuSO/sub 4/, ZnSO/sub 4/, CdSO/sub 4/, Sevin, heptachlor, and fenitrothion did not change the preferred temperature significantly. Comparison with other published results indicates that those substances that increase the preferred temperature are more toxic (based on relevant changes in 24-h LC50) at low temperatures and vice versa. It is suggested that such shifts in selected temperature may be of potential immediate, short-term, survival value to the fish. (auth)

Cannibalism in non-native brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss stream-dwelling populations.

Science.gov (United States)

Musseau, C; Vincenzi, S; Jesenšek, D; Crivelli, A J

2017-12-01

Introduced and allopatric populations of brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss were sampled in Slovenia for stable isotope analysis to assess dietary niche shifts through ontogeny and estimate the propensity for cannibalism. Both S. trutta and O. mykiss are cannibals, with higher average relative contribution of conspecific assimilated energy for S. trutta (27·9%) compared with O. mykiss (7·7%). The smallest cannibal was 166 mm in the S. trutta population and 247 mm in the O. mykiss population. © 2017 The Fisheries Society of the British Isles.

Analysis of strontium-90 in the bones of brown trout (Salmo trutta) from Lake Ontario

International Nuclear Information System (INIS)

Manos, C.G. Jr.; Kinney, R.M.; Lisk, D.J.

1993-01-01

Radionuclides such as Sr-90, mainly from liquid effluent releases from nuclear power generating facilities, can contaminate water and biota. Lake Ontario ultimately receives the outflow from each of the other Great Lakes. In the work reported, brown trout (Salmo trutta) were captured from Lake Ontario and their entire skeletal bone material analyzed for Sr-90. They showed an average concentration of Sr-90 approximately four times greater than control brown trout captured from nearby Cayuga Lake in Central New York State which has no nuclear generating facilities. The results are discussed considering fallout and hydrographic considerations. (author)

Fillet quality and processing attributes of postsmolt Atlantic salmon, Salmo salar, fed a fishmeal-free diet and a fishmeal-based diet in recirculation aquaculture systems

Science.gov (United States)

Many studies have evaluated the adequacy of alternate ingredient diets for Atlantic salmon, Salmo salar, mainly with focus on fish performance and health; however, comprehensive analysis of fillet quality is lacking, particularly for salmon fed these diets in recirculation aquaculture systems (RAS)....

Comparative cardiac pathological changes of Atlantic salmon (Salmo salar L.) affected with heart and skeletal muscle inflammation (HSMI), cardiomyopathy syndrome (CMS) and pancreas disease (PD)

DEFF Research Database (Denmark)

Yousaf, Muhammad Naveed; Koppang, Erling Olaf; Skjødt, Karsten

2013-01-01

The heart is considered the powerhouse of the cardiovascular system. Heart and skeletal muscle inflammation (HSMI), cardiomyopathy syndrome (CMS) and pancreas disease (PD) are cardiac diseases of marine farmed Atlantic salmon (Salmo salar) which commonly affect the heart in addition to the skeletal...

Testing three common stocking methods: Differences in smolt size, migration rate and timing of two strains of stocked Atlantic salmon ( Salmo salar )

DEFF Research Database (Denmark)

Birnie-Gauvin, Kim; Larsen, Martin Hage; Thomassen, Søren T.

2018-01-01

The influence of three common stocking practices for two strains (Ätran and Burrishoole) of hatchery-reared Atlantic salmon, Salmo salar, on smolt size, migration probability and migration timing were investigated in situ. Using a common garden experiment, fish from these populations were release...... to inherited factors, and emphasize the importance of considering age of fish and time spent in the hatchery when stocking populations in the wild to maximize smolt output......The influence of three common stocking practices for two strains (Ätran and Burrishoole) of hatchery-reared Atlantic salmon, Salmo salar, on smolt size, migration probability and migration timing were investigated in situ. Using a common garden experiment, fish from these populations were released...... as fry, half-year olds and oneyear olds. Our results indicate that fish released at the fry and half-year stage produce smaller smolts, and migrate later in the year than their counterparts released at one-year of age, for both the Ätran and the Burrishoole populations. While fry had the lowest...

Estimation of sodium uptake through the gill of the rainbow trout Salmo gairdneri

Energy Technology Data Exchange (ETDEWEB)

Gardaire, E.; Avella, M.; Isaia, J.; Bornancin, M.; Mayer-Gostan, N.

1985-01-01

Sodium exchanges through the gill epithelia were estimated in the rainbow trout, Salmo gairdneri, using the perfused head technique. The head tissues accumulate radioactivity. In addition there exists an extrabranchial entry of sodium, which is 20 times smaller than the branchial one. The study of the evolution of venous and arterial sodium specific activities as a function of time is necessary before flux measurements are achieved. Contrary to previous studies, an uptake at the primary lamella level is demonstrated. Uptake of sodium through the secondary lamellae can be measured rapidly while at least 30 min are needed for measurement of uptake through the primary lamellae. Chloride cells of the primary lamellae contribute to about 20% of the total sodium uptake.

Sensory and chemical changes in farmed Atlantic salmon ( Salmo salar ) during frozen storage

DEFF Research Database (Denmark)

Refsgaard, Hanne; Brockhoff, P.B.; Jensen, Benny

1998-01-01

Farmed Atlantic salmon (Salmo salar) were stored as fillets at -10 and -20 degrees C and whole at -30 degrees C. The most pronounced sensory changes were first recognized by the assessors, when the salmon samples were in the oral cavity, and were significant increases in train oil taste, metal...... during storage. The content of lipid hydroperoxides and free fatty acids also increased during storage, and the changes were fastest in salmon stored at -10 degrees C. A decrease in highly unsaturated fatty acids was observed in salmon stored at -10 and -20 degrees C. Peroxide values and the content...... of free fatty acids were shown by a partial least-squares analysis to be the best of the instrumental data in describing the sensory changes....

Growth and osmoregulation in Salmo salar L. juveniles 1+, 1½ + and 2+ reared under restrained salinity

Directory of Open Access Journals (Sweden)

José Fernando Magalhães Gonçalves

2013-02-01

Full Text Available The freshwater phase of Atlantic salmon Salmo salar L vary between one and eight years. The reduction of the freshwater phase is desirable to reduce freshwater usage, human resources and to increase year round availability of pan-sized salmon. Three trials were conducted to investigate the possibility of supply the market in a year-round basis, with pan-sized Atlantic salmon Salmo salar L. (250-300 g in Portugal (southern limit of the natural distribution of this species. This study primarily aimed to compare the osmoregulatory ability and growth of different fish sizes, smolts 1+ (trial 1, 1.5+ (trial 2 and 2+ (trial 3, in freshwater and seawater conditions. Additionally, effects of photoperiod were determined in smolts 1.5+ (trial 2 for both freshwater and seawater groups. The increments in the plasma osmolality and chlorine concentrations after seawater transfer suggest an identical development in the hypo-osmoregulation capacity among the different age classes. In all trials, weight gain was smaller after 30 d of saltwater transfer when compared to fish reared in freshwater. However, the growth depression was temporary. Seawater group showed a compensatory growth in the immediate months, which permitted an improvement in growth rates. At the end of trials there were minor differences on growth performance between freshwater and seawater groups. Specific growth rates varied between 0.7 and 1.0 % day-1, according to the age and /or size and transfer season.

Statistical methods for estimating normal blood chemistry ranges and variance in rainbow trout (Salmo gairdneri), Shasta Strain

Science.gov (United States)

Wedemeyer, Gary A.; Nelson, Nancy C.

1975-01-01

Gaussian and nonparametric (percentile estimate and tolerance interval) statistical methods were used to estimate normal ranges for blood chemistry (bicarbonate, bilirubin, calcium, hematocrit, hemoglobin, magnesium, mean cell hemoglobin concentration, osmolality, inorganic phosphorus, and pH for juvenile rainbow (Salmo gairdneri, Shasta strain) trout held under defined environmental conditions. The percentile estimate and Gaussian methods gave similar normal ranges, whereas the tolerance interval method gave consistently wider ranges for all blood variables except hemoglobin. If the underlying frequency distribution is unknown, the percentile estimate procedure would be the method of choice.

Genetic detection of sex-specific dispersal in historical and contemporary populations of anadromous brown trout Salmo trutta

DEFF Research Database (Denmark)

Bekkevold, Dorte; Hansen, Michael Møller; Mensberg, Karen-Lise Dons

2004-01-01

The study of sex-biased dispersal has attracted considerable attention in birds and mammals, but less in other taxa, including fishes. We analysed sex-specific dispersal in historical (1910s and 1950s) and contemporary (1990s) samples of anadromous brown trout Salmo trutta. We tested the hypothesis...... that dispersal is unbiased using information from microsatellite DNA and applying an assignment index for 11 temporally and spatially separated samples. Our results are most consistent with brown trout dispersal being male biased, and provide no evidence of female bias. We found no evidence that dispersal...

Revisiting the mitogenomic phylogeny of Salmoninae: new insights thanks to recent sequencing advances

Directory of Open Access Journals (Sweden)

Jose L. Horreo

2017-09-01

Full Text Available The phylogeny of the Salmonidae family, the only living one of the Order Salmoniformes, remains still unclear because of several reasons. Such reasons include insufficient taxon sampling and/or DNA information. The use of complete mitochondrial genomes (mitogenomics could provide some light on it, but despite the high number of mitogenomes of species belonging to this family published during last years, an integrative work containing all this information has not been done. In this work, the phylogeny of 46 Salmonidae species was inferred from their mitogenomic sequences. Results include a Bayesian molecular-dated phylogenetic tree with very high statistical support showing Coregoninae and Salmoninae as sister subfamilies, as well as several new phylogenetic relationships among species and genus of the family. All these findings contribute to improve our understanding of the Salmonidae systematics and could have consequences on related evolutionary studies, as well as highlight the importance of revisiting phylogenies with integrative studies.

Development of the retinotopic organization in Salmo gairdneri

International Nuclear Information System (INIS)

Pinganaud, G.

1987-01-01

The progression of the retinotopic organization in the optic nerve projections to the contralateral thalamus and tectum was studied in Salmo gairdneri from hatching stage to 3 month old stage. After quadratic lesions of the temporal, dorsal, nasal, or ventral retina, the animals were separated in two groups: one used for Fink and Heimer method or electron microscopic observation and the other one for radioautography after injection in the operated eye of [ 14 C] or [ 3 H]proline. The analysis of the projections of each retinal quadrant revealed: (1) Projections to thalamus and pretectum are ignorganized and appear progressively during development. On the contrary in tectum and corpus geniculatum, the visual projections are retinotopically organized since hatching. (2) In the whole retino-tectal system, two subsystems develop differently: the naso-ventral retina reaches precociously its permanent target (the posterior tectum), the temporo-dorsal part of the retina links to the anterior tectum and shifts laterally during the first month after hatching, from medial to antero-lateral for temporal projections. The shifting of projections is correlated with development of the medial fascicle of the optic tract. So it appears that the pathways play an important role in the spatio-temporal ordered pattern of terminations of retinal fibers on the tectal surface during development. (author)

Problems Threatening the Tigris Trout (Salmo tigridis Turan, Kottelat & Bektaş, 2011 Stock in Çatak Stream and Some Recommendations

Directory of Open Access Journals (Sweden)

Mustafa AKKUŞ

2017-12-01

Full Text Available This study was carried out to reveal the problems threatening Salmo tigridis stock inhabited in Çatak Stream and to offer some solutions to overcome these problems. Çatak is the largest stream of the region and located at 81 km southern of the Van city center. Salmo tigridis, which is only distributed in Çatak and Bahçesaray streams, faces the danger of extinction. In this study, it was observed that sand-graveling activities at Çatak Stream muddied the stream and destroyed appropriate reproduction habitats. Another problem is that Çatak Stream's over-destruction of vegetation in the catchment basin increases flood risk and flood-related sudden flow increases. In addition, it was determined that studies carried out for river improvement and flood control disturbed the natural flow regime of the stream, leading to deterioration in the base and coastal structure. Another threat is the rainbow trout (Oncorhynchus mykiss that escape from fish farms. Catching with prohibited methods and fishing gears is also a problem that threatens the future of native trout stock in the stream. With this study, the problems that threaten the tigris trout stock in Çatak Stream were identified and some proposals were presented.

From sneaker to parental male: change of reproductive traits in the black goby, Gobius niger (Teleostei, Gobiidae).

Science.gov (United States)

Immler, Simone; Mazzoldi, Carlotta; Rasotto, Maria Berica

2004-02-01

This study focuses on the consequences of the switch of tactic from parasitic to parental male in the black goby, Gobius niger (Teleostei: Gobiidae), a species showing two alternative male mating tactics. Older and larger males defend nests, court, and perform parental care on eggs, while younger and smaller ones behave as parasites, sneaking into nests while spawning occurs. Males adopting different tactics are known to present differences in primary and secondary sex traits. The social context of sneaker males was manipulated to induce a tactic switch. Sneakers were kept under two different experimental treatments with or without a female, and under exclusion of male-male competition. Males changed tactics, courting females, spawning, and performing parental care. All males showed substantial changes in primary sexual traits, such as a reduction in gonadal development and an increase in the investment in accessory structures. The experimental groups differed in the functionality of gonads and accessory organs and in the development of the secondary sex traits. These results demonstrate that the moment of switching is not genetically fixed in the black goby. Sneaker males are able to quickly reallocate energy in primary and secondary sex traits, in accordance with the adopted tactic. Several aspects of this flexible reproductive pattern resemble the socially controlled sex change found in sequential hermaphrodites. Copyright 2004 Wiley-Liss, Inc.

Temporal stability and rates of post-depositional change in geochemical signatures of brown trout Salmo trutta scales.

Science.gov (United States)

Ryan, D; Shephard, S; Kelly, F L

2016-09-01

This study investigates temporal stability in the scale microchemistry of brown trout Salmo trutta in feeder streams of a large heterogeneous lake catchment and rates of change after migration into the lake. Laser-ablation inductively coupled plasma mass spectrometry was used to quantify the elemental concentrations of Na, Mg, Mn, Cu, Zn, Ba and Sr in archived (1997-2002) scales of juvenile S. trutta collected from six major feeder streams of Lough Mask, County Mayo, Ireland. Water-element Ca ratios within these streams were determined for the fish sampling period and for a later period (2013-2015). Salmo trutta scale Sr and Ba concentrations were significantly (P < 0·05) correlated with stream water sample Sr:Ca and Ba:Ca ratios respectively from both periods, indicating multi-annual stability in scale and water-elemental signatures. Discriminant analysis of scale chemistries correctly classified 91% of sampled juvenile S. trutta to their stream of origin using a cross-validated classification model. This model was used to test whether assumed post-depositional change in scale element concentrations reduced correct natal stream classification of S. trutta in successive years after migration into Lough Mask. Fish residing in the lake for 1-3 years could be reliably classified to their most likely natal stream, but the probability of correct classification diminished strongly with longer lake residence. Use of scale chemistry to identify natal streams of lake S. trutta should focus on recent migrants, but may not require contemporary water chemistry data. © 2016 The Fisheries Society of the British Isles.

Genetic variation in brown trout Salmo trutta across the Danube, Rhine, and Elbe headwaters: a failure of the phylogeographic paradigm?

Science.gov (United States)

Lerceteau-Köhler, Estelle; Schliewen, Ulrich; Kopun, Theodora; Weiss, Steven

2013-08-26

Brown trout Salmo trutta have been described in terms of five major mtDNA lineages, four of which correspond to major ocean basins, and one, according to some authors, to a distinct taxon, marbled trout Salmo marmoratus. The Atlantic and Danubian lineages of brown trout meet in a poorly documented contact zone in Central Europe. The natural versus human mediated origin of the Atlantic lineage in the upper Danube is a question of both theoretical and practical importance with respect to conservation management. We provide a comprehensive population genetic analysis of brown trout in the region with the aim of evaluating the geographic distribution and genetic integrity of these two lineages in and around their contact zone. Genetic screening of 114 populations of brown trout across the Danube/Rhine/Elbe catchments revealed a counter-intuitive phylogeographic structure with near fixation of the Atlantic lineage in the sampled portions of the Bavarian Danube. Along the Austrian Danube, phylogeographic informative markers revealed increasing percentages of Danube-specific alleles with downstream distance. Pure Danube lineage populations were restricted to peri-alpine isolates within previously glaciated regions. Both empirical data and simulated hybrid comparisons support that trout in non-glaciated regions north and northeast of the Alps have an admixed origin largely based on natural colonization. In contrast, the presence of Atlantic basin alleles south and southeast of the Alps stems from hatchery introductions and subsequent introgression. Despite extensive stocking of the Atlantic lineage, little evidence of first generation stocked fish or F1 hybrids were found implying that admixture has been established over time. A purely phylogeographic paradigm fails to describe the distribution of genetic lineages of Salmo in Central Europe. The distribution pattern of the Atlantic and Danube lineages is extremely difficult to explain without invoking very strong

The effects of long-term 20 mg/L carbon dioxide exposure on the health and performance of Atlantic salmon Salmo salar post-smolts in water recirculation aquaculture systems

Science.gov (United States)

Previous research and experience has linked elevated dissolved carbon dioxide (CO2) to reduced growth performance, poor feed conversion, and a variety of health issues in farm-raised fish, including Atlantic salmon Salmo salar. Supplemental control measures in water recirculation aquaculture systems...

Endocrine changes associated with spawning behavior and social stimuli in a wild population of rainbow trout (Salmo gairdneri). II. Females

OpenAIRE

Liley, N.R.; Fostier, Alexis; Breton, B.; Tan, E.S.P.

1986-01-01

Rainbow trout (Salmo gairdneri) were collected from a natural spawning population at Pennask Lake, B.C. Blood samples taken from female trout at different stages of spawning were assayed by radioimmunoassay for gonadotropin (GtH), estradiol-17 beta (E2), androgens, including testosterone (T), and 17α-hydroxy-20 β-dihydroprogesterone (17,20-P). Plasma levels of androgen and estradiol were highest in females sampled shortly before ovulation (ogreeno females) and declined in ovulated and sexuall...

Influence of small hydropower plants on brown trout (Salmo trutta L. population in Mislinja River

Directory of Open Access Journals (Sweden)

Blaž Cokan

2013-12-01

Full Text Available The brown trout (Salmo trutta L. in the Mislinja River has been endangered for years because of small hydroelectric power plants. To find out how they are affecting the population of the brown trout in the Mislinja River, we conducted a sampling of the brown trout, using a generating set. We measured the length and weight of all caught specimens and analysed the obtained data. The results are presented in this paper, e.g., biomass, estimations of abundance, average weight, average length and number of captured brown trout. We discovered that the population of the brown trout has decreased in all the sections where water has been taken away for small hydroelectric power plants.

Assessment of digestive enzymes activity during the fry development of the endangered Caspian brown trout Salmo caspius.

Science.gov (United States)

Zamani, A; Hajimoradloo, A; Madani, R; Farhangi, M

2009-09-01

The study of digestive enzymes activity at Salmo caspius fry showed that enzymes were available at the moment of mouth opening on the first day post hatching (dph) and the activity of enzymes showed no significant difference from the hatching day 28 dph. An increased activity was seen between 32 and 43 dph and this activity was significantly higher than the activity during the first 28 days. In the primary stages after yolk sac resorption (43-58 dph), enzymes activity showed an increased profile, however none of them showed a significant difference between 43 and 58 dph.

Vaccination improves survival of Baltic salmon ( Salmo salar ) smolts in delayed release sea ranching (net-pen period)

DEFF Research Database (Denmark)

Buchmann, Kurt; Dalsgaard, Inger; Nielsen, Michael Engelbrecht

1997-01-01

Baltic salmon (Salmo salar) of the Finnish Iijoki stock were hatched and reared in freshwater in a salmon hatchery on the Danish island of Bornholm in the Baltic sea. Salmon parr were divided in three groups each comprising 22 000 fish. One group was vaccinated by intraperitoneal injection....... In contrast, no increase of titres was seen in the bath vaccinated and untreated groups. Marked cellular reactions in the abdominal cavity of injected fish were registered. A total of 3000 fish have been tagged and released to evaluate the effect of vaccination on the recapture rate. The implications...

Daytime habitat selection for juvenile parr brown trout (Salmo trutta) in small lowland streams

DEFF Research Database (Denmark)

Conallin, J.; Boegh, E.; Olsen, M.

2014-01-01

Physical habitat is important in determining the carrying capacity of juvenile brown trout, and within freshwater management. Summer daytime physical habitat selection for the parr lifestage (7-20 cm) juvenile brown trout (Salmo trutta) was assessed in 6 small lowland streams. Habitat preference...... was determined for the four variables; water velocity, water depth, substrate and cover, and the preferences for physical habitat selection were expressed in terms of habitat suitability indices (HSI's). The statistical confidence of HSI's was evaluated using power analysis. It was found that a minimum of 22...... fish observations was needed to have statistical confidence in the HSIs for water depth, and a minimum of 92 fish observations for water velocity during daytime summer conditions. Generally parr were utilising the deeper habitats, indicating preference for deeper water. Cover was also being selected...

Physiological preparedness and performance of Atlantic salmon Salmo salar smolts in relation to behavioural salinity preferences and thresholds

Science.gov (United States)

Stich, D.S.; Zydlewski, G.B.; Zydlewski, Joseph D.

2015-01-01

This study investigated the relationships between behavioural responses of Atlantic salmon Salmo salarsmolts to saltwater (SW) exposure and physiological characteristics of smolts in laboratory experiments. It concurrently described the behaviour of acoustically tagged smolts with respect to SW and tidal cycles during estuary migration. Salmo salar smolts increased their use of SW relative to fresh water (FW) from April to June in laboratory experiments. Mean preference for SW never exceeded 50% of time in any group. Preference for SW increased throughout the course of smolt development. Maximum continuous time spent in SW was positively related to gill Na+, K+-ATPase (NKA) activity and osmoregulatory performance in full-strength SW (measured as change in gill NKA activity and plasma osmolality). Smolts decreased depth upon reaching areas of the Penobscot Estuary where SW was present, and all fish became more surface oriented during passage from head of tide to the ocean. Acoustically tagged, migrating smolts with low gill NKA activity moved faster in FW reaches of the estuary than those with higher gill NKA activity. There was no difference in movement rate through SW reaches of the estuary based on gill NKA activity. Migrating fish moved with tidal flow during the passage of the lower estuary based on the observed patterns in both vertical and horizontal movements. The results indicate that smolts select low-salinity water during estuary migration and use tidal currents to minimize energetic investment in seaward migration. Seasonal changes in osmoregulatory ability highlight the importance of the timing of stocking and estuary arrival.

The influence of environmental abiotic factors on the qualitative and quantitative structure of ichthyofauna from predeltaic Danube area

Directory of Open Access Journals (Sweden)

Petronela Georgiana Calin Sandu

2013-05-01

Full Text Available The aim of the paper  is to analyse the influence of environmental factors on the capture and fish communities structure from Danube, between Siret River and Prut River mouth. Fish were collected from April to December 2012 in four fishing areas. During the year, 4910 kg, respectively 7121 fish of 31 species were collected. Cyprinidae, the dominant family, 54.84% in term of number of species, was represented by 17 species (Cyprinus carpio, Carassius gibelio, Barbus barbus, Abramis brama, Abramis sapa, Blicca bjoerkna, Leuciscus idus, Vimba vimba, Aspius aspius, Pelecus cultratus, Chondrostoma nasus, Ctenopharingodon idella, Hypophthalmichthys molitrix, Hypophthalmichthys nobilis, Scardinius erythrophthalmus, Rutilus rutilus, Alburnus alburnus. Other families had the following structure: Percidae (16.13% with 5 species (Sander lucioperca, Zingel zingel, Zingel streber, Perca fluviatilis, Gymnocephalus schraetzer, Acipenseridae (12.90% with 4 species (Huso huso, Acipenser stellatus, Acipenser ruthenus, Acipenser gueldenstaedtii, Clupeidae (6.45% with two species (Alosa immaculata, Alosa tanaica, Siluridae (3.23% with one species (Silurus glanis, Esocidae (3.23% with one species (Esox lucius  and Salmonidae (3.23% with one species also (Salmo labrax. The highest capture was 2977.93 kg (60.65%, during the spring season (April-May, followed by autumn season (September–November, with 992.39 kg (20.21%. The water level and water flow showed high correlation with both number and total catch, respectively.

Quality Index Method (QIM) scheme developed for farmed Atlantic salmon ( Salmo salar )

DEFF Research Database (Denmark)

Sveinsdóttir, K.; Hyldig, Grethe; Martinsdóttir, E.

2003-01-01

The aim of the study was to develop 'Quality Index Method (QIM) scheme for raw, farmed Atlantic salmon (Salmo salar) and to evaluate the scheme. in a shelf life study. QIM is based on the evaluation of key parameters in the deterioration of seafood's. Demerit points are assigned to selected...... parameters according to their importance and a Quality Index (QI) is established by cumulating the resulting scores. The maximum storage time in ice was determined with Quantitative Descriptive Analysis (QDA) of the salmon after cooking and found to be 20-21 days. This was used as a reference to enable...... prediction of the remaining storage time of raw salmon in ice with QIM. The calculated QI evolved linearly with storage time in ice (QI=0.82x (days in ice)+0.18, R-2=0.97). Individual salmon varied in QI within each storage day. However, the multivariate analysis (PLS1) demonstrated that storage time could...

Three brown trout Salmo trutta lineages in Corsica described through allozyme variation.

Science.gov (United States)

Berrebi, P

2015-01-01

The brown trout Salmo trutta is represented by three lineages in Corsica: (1) an ancestral Corsican lineage, (2) a Mediterranean lineage and (3) a recently stocked domestic Atlantic S. trutta lineage (all are interfertile); the main focus of this study was the ancestral Corsican S. trutta, but the other lineages were also considered. A total of 38 samples captured between 1993 and 1998 were analysed, with nearly 1000 individuals considered overall. The Corsican ancestral lineage (Adriatic lineage according to the mitochondrial DNA control region nomenclature, AD) mostly inhabits streams in the southern half of the island; the Mediterranean lineage (ME) is present more in the north, especially in Golu River, but most populations are an admixture of these lineages and the domestic Atlantic S. trutta (AT). Locations where the Corsican ancestral S. trutta is dominant are now protected against stocking and sometimes fishing is also forbidden. The presence of the Corsican S. trutta is unique in France. © 2014 The Fisheries Society of the British Isles.

Genetic variation in steelhead (Salmo gairdneri) from the north coast of Washington

Science.gov (United States)

Reisenbichler, R.R.; Phelps, S.R.

1989-01-01

Steelhead (Salmo gairdneri) collected from various sites in nine drainages in northwestern Washington were genetically characterized at 65 protein-coding loci by starch-gel electrophoresis. Genetic differentiation within and among drainages was not significant, and genetic variation among drainages was much less than that reported in British Columbia; these results may be the consequence of gene flow from hatchery stocks that have been released in Washington since the 1940's. Allele frequencies varied significantly among year-classes (hence, genetic characterization studies must include data from several year-classes), and also between hatchery fish (including a stock developed with local wild fish) and wild fish, indicating that few wild fish have been successfully and routinely included in hatchery brood stocks. Conservation of genetic diversity along the north coast of Washington should be facilitated by reducing the numbers of hatchery fish that spawn in streams and by including wild fish in hatchery brood stocks.

Survival and progression rates of anadromous brown trout kelts Salmo trutta during downstream migration in freshwater and at sea

DEFF Research Database (Denmark)

Aarestrup, Kim; Baktoft, Henrik; Thorstad, EB

2015-01-01

The marine migration of post-spawning anadromous fish remains poorly understood. The present study examined survival and progression rates of anadromous brown trout Salmo trutta L. after spawning (kelts) during downriver, fjord, and sea migration. Kelts (n = 49) were captured in the Danish River...... completing the reach within 4 d, suggesting that the kelts spent limited time foraging after returning to the fjord. The total survival during the entire marine migration, including the fjord, was a minimum of 29%. Our study provides data that are important for management of anadromous brown trout...

Occurrence and variation of egg cannibalism in brown trout Salmo trutta

Science.gov (United States)

Aymes, Jean-Christophe; Larrieu, Maider; Tentelier, Cédric; Labonne, Jacques

2010-04-01

Egg cannibalism is a common behavior among fish taxa and is largely studied in species with parental care. Heterocannibalism and filial cannibalism have both been reported in salmonids, a group with no extended parental care, but the topic remained somewhat under-documented, especially in brown trout ( Salmo trutta). In the present study, 83 spawning events were recorded finely with high-resolution video in three natural populations. Redd covering dynamics by females and the timing of cannibalism showed that eggs were vulnerable mainly during the first 120 s after spawning. Cannibalism occurred in 25% of spawnings and was principally perpetrated by peripherals but the sires also cannibalized their brood, especially after multiple mating. The probability of cannibalism increased with operational sex ratio but did not correlate with the date in spawning season. Occurrence of cannibalism also differed between populations. Our results suggest that such behavior is frequent and may reduce the fitness of parents. Its evolutionary implications for population ecology should be considered, since it appeared to be controlled by environmental and spatial factors.

Reduced rearing density increases postrelease migration success of Atlantic salmon (Salmo salar) smolts

DEFF Research Database (Denmark)

Larsen, Martin Hage; Johnsson, Jörgen I; Näslund, Joacim

2016-01-01

during rearing in the hatchery. However, individuals reared at reduced density had less eroded dorsal fins and opercula relative to those from the high-density treatment. In the stream, the downstream migration success was 16% higher for fish reared at reduced density than for conspecifics kept at high-density......The overall aim of this study was to investigate the effect of rearing density on the post-release survival of Atlantic salmon (Salmo salar) smolts during seaward migration. Fish were either reared at conventional hatchery density or at one-third of conventional density. Three hundred one-year old...... smolts from each density treatment were individually tagged with passive integrated transponder (PIT) tags and released 3.2 km upstream of a stationary antenna array in a natural stream. There were no significant differences in length, body mass, or condition between fish from the two density treatments...

Development of Atlantic salmon (Salmo salar) eggs and alevins under varied temperature regimes

Energy Technology Data Exchange (ETDEWEB)

Peterson, R H; Spinney, H C.E.; Sreedharan, A

1977-01-01

Atlantic salmon (Salmo salar) eggs and alevins were raised under conditions where the temperature was systematically varied either at fertilization, at the eyed egg stage, or at hatching. Mortality was more than 20% in eggs started immediately after fertilization at constant incubation temperatures <4/sup 0/C as compared with 5% or less at temperatures >4/sup 0/C. Alevins that eyed at 8/sup 0/C and higher were progressively smaller the higher the temperature. The optimum temperature from fertilization to eye pigmentation was near 6/sup 0/C. Eyed eggs reared at lower temperatures until hatching were larger than those hatched at higher temperatures. This size differential was maintained until the yolk was completely absorbed at all posthatching temperatures investigated. Sudden decreases in temperature at the eyed egg and hatching stages induced severe edema of the alevin yolk sac, resulting in slower growth and increased mortality.

Pre-migratory differentiation of wild brown trout Salmo trutta into migrant and resident individuals

DEFF Research Database (Denmark)

Nielsen, Christian; Aarestrup, Kim; Nørum, Ulrik

2003-01-01

In February to March, wild brown trout Salmo trutta were captured by electrofishing in a natural watercourse (tributaries of the River Lille Aa, Denmark), individually tagged (Passive Integrated Transponders), and released. Representatives of the tagged brown trout were recaptured on the release......+,K+-ATPase analysis. Based on repetitive gill enzyme analysis in individual fish, a retrospective analysis of the rate of development in individual brown trout ultimately classified as migrants or residents was performed. Two months prior to migration, a bimodal morphological and physiological (gill Na...... a smolt-like appearance before the onset of migration and had higher rate of change of gill Na+,K+-ATPase activity than fish remaining residents. The rate of change of gill Na+,K+-ATPase activity was independent of the distance migrated to the trap (3-28 km). Thus in bimodal wild brown trout populations...

Tissue astaxanthin and canthaxanthin distribution in rainbow trout (Oncorhynchus mykiss) and Atlantic salmon (Salmo salar).

Science.gov (United States)

Page, G I; Davies, S J

2006-01-01

A comparative investigation of tissue carotenoid distribution between rainbow trout, Oncorhynchus mykiss, and Atlantic salmon, Salmo salar, was undertaken to identify the relative efficiency of utilization of astaxanthin and canthaxanthin. Higher apparent digestibility coefficients (ADCs) (96% in trout vs. 28-31% in salmon; Ptrout vs. 5.5% in salmon; Ptrout. Astaxanthin deposition was higher than canthaxanthin in rainbow trout, while the reverse was true for Atlantic salmon, suggesting species-specificity in carotenoid utilization. The white muscle (95% in trout vs. 93% in salmon) and kidneys (0.5% in trout vs. 0.2% in salmon) represented higher proportions of the total body carotenoid pool in rainbow trout than in Atlantic salmon (Ptrout; Ptrout. Liver catabolism is suspected to be a critical determinant in carotenoid clearance, with higher catabolism expected in Atlantic salmon than in rainbow trout.

Comparison of vegetable shortening and cocoa butter as vehicles for cortisol manipulation in Salmo trutta

DEFF Research Database (Denmark)

Birnie-Gauvin, Kim; Peiman, K. S.; Larsen, M. H.

2018-01-01

This study demonstrates that vegetable shortening and cocoa butter are two effective vehicles for intraperitoneal cortisol implants in juvenile teleosts, specifically brown trout Salmo trutta, residing in north temperate freshwater environments. Each vehicle showed a different pattern of cortisol...... elevation. Vegetable shortening was found to be a more suitable vehicle for long-term cortisol elevation [elevated at 3, 6 and 9 days post treatment (dpt)], while cocoa butter may be better suited for short-term cortisol elevation (only elevated at 3 dpt). Additionally, plasma cortisol levels were higher...... with cortisol–vegetable shortening than with cortisol–cocoa butter implants. Plasma glucose levels were elevated 6 and 9 dpt for fishes injected with cortisol–vegetable shortening, but did not change relative to controls and shams in cortisol–cocoa butter fishes. In conclusion, vegetable shortening and cocoa...

pH preference and avoidance responses of adult brook trout Salvelinus fontinalis and brown trout Salmo trutta.

Science.gov (United States)

Fost, B A; Ferreri, C P

2015-03-01

The pH preferred and avoided by wild, adult brook trout Salvelinus fontinalis and brown trout Salmo trutta was examined in a series a laboratory tests using gradual and steep-gradient flow-through aquaria. The results were compared with those published for the observed segregation patterns of juvenile S. fontinalis and S. trutta in Pennsylvania streams. The adult S. trutta tested showed a preference for pH 4·0 while adult S. fontinalis did not prefer any pH within the range tested. Salmo trutta are not found in Pennsylvania streams with a base-flow pH < 5·8 which suggests that S. trutta prefer pH well above 4·0. Adult S. trutta displayed a lack of avoidance at pH below 5·0, as also reported earlier for juveniles. The avoidance pH of wild, adult S. fontinalis (between pH 5·5 and 6·0) and S. trutta (between pH 6·5 and 7·0) did not differ appreciably from earlier study results for the avoidance pH of juvenile S. fontinalis and S. trutta. A comparison of c.i. around these avoidance estimates indicates that avoidance pH is similar among adult S. fontinalis and S. trutta in this study. The limited overlap of c.i. for avoidance pH values for the two species, however, suggests that some S. trutta will display avoidance at a higher pH when S. fontinalis will not. The results of this study indicate that segregation patterns of adult S. fontinalis and S. trutta in Pennsylvania streams could be related to pH and that competition with S. trutta could be mediating the occurrence of S. fontinalis at some pH levels. © 2015 The Fisheries Society of the British Isles.

Application of Quality Index Method (QIM) scheme in shelf-life study of farmed Atlantic salmon ( Salmo salar )

DEFF Research Database (Denmark)

Sveinsdóttir, K.; Martinsdóttir, E.; Hyldig, Grethe

2002-01-01

measurements (compression test). Maximum storage time in ice was determined with QDA and fat content by Soxhlet extraction. A high correlation between QIM and storage time in ice was found. Storage time could be predicted with +/- 2 d. TVC increased exponentially with storage and was dominated by H2S......Salmon (Salmo salar) was stored in ice up to 24 d, and changes during storage were observed with sensory evaluation using the Quality Index Method (QIM), and Quantitative Descriptive Analysis (QDA), total viable counts (TVC), hydrogen sulfide (H2S)-producing bacteria, and instrumental texture......-producing bacteria after 20 d in ice, which was the maximum storage time. Texture measurements indicated softening of salmon flesh with storage...

Characterization of branchial transepithelial calcium fluxes in freshwater trout, Salmo gairdneri

International Nuclear Information System (INIS)

Perry, S.F.; Flik, G.

1988-01-01

Experiments were performed to determine whether gill transepithelial calcium fluxes in the freshwater trout (Salmo gairdneri) are passive or require active transport and to characterize the mechanism involved. A comparison of the in vivo unidirectional flux ratios with the flux ratios calculated according to the transepithelial electrochemical gradients revealed that calcium uptake from the water requires active transport of Ca 2+ . The inhibition of calcium uptake by external lanthanum, the specific deposition of lanthanum on the apical surface of chloride cells, and the favorable electrochemical gradient for calcium across the apical membrane suggest that the initial step in branchial calcium uptake is the passive entry of calcium into the cytosol of chloride cells through apical channels that are permeable to calcium. The study of gill basolateral plasma membrane vesicles demonstrated the existence of a high-affinity calmodulin-dependent calcium-transporting system. This system actively transports calcium from the cytosol of chloride cells into the plasma against a sizeable electrochemical gradient, thereby completing the transepithelial uptake of calcium. Calcium efflux occurs passively through paracellular pathways between chloride cells and adjacent pavement cells or between neighboring pavement cells

The albumin of the brown trout (Salmo trutta) is a glycoprotein.

Science.gov (United States)

Metcalf, V J; Brennan, S O; Chambers, G K; George, P M

1998-07-28

The albumin from an Atlantic salmonid, the brown trout (Salmo trutta), is 1730 Da higher in molecular mass than the albumin from a Pacific salmonid, the chinook salmon (Oncorhynchus tshawytscha), at 65230 Da. Digestion with neuraminidase revealed that purified brown trout albumin contained sialic acid while chinook salmon albumin did not. Concanavalin A-sepharose affinity chromatography was used to purify a glycopeptide from a total tryptic digest of brown trout albumin. The mass of this glycopeptide (3815 Da) was determined by mass spectrometry, and the sequence largely confirmed by N-terminal sequencing. The identified sequence of IAHCCNQSYSM-, contains an Asn-Gln-Ser glycosylation site and is identical to residues 475-485 derived from the cDNA of the albumin from the Atlantic salmon, the closest relative of the brown trout. Glycosylation of albumin is very unusual, and has not been identified in either reptilian or mammalian albumins. The finding of a glycoalbumin in salmonids, ancient members of the teleost fish subclass, coupled with evidence of albumin glycosylation in the oldest vertebrates, agnathans, as well as amphibians, suggests that albumin was originally a glycoprotein, but lost this modification sometime between the divergence of amphibians and reptiles.

Bioaccumulation, distribution and retention of 63Ni2+ in the brown trout (Salmo trutta)

International Nuclear Information System (INIS)

Tjaelve, Hans; Gottofrey, James; Borg, Kathleen

1988-01-01

Brown trout, Salmo trutta, were exposed to water containing 0.1 or 10 μgl -1 of 63 Ni 2+ for 1 or 3 weeks. Additional trout were exposed to 0.1 or 10 μgl -1 of 63 Ni 2+ during 3 weeks followed by a 1- or 3-week period without exposure to the metal. At termination of the experimental periods the uptake and distribution of the 63 Ni 2+ in the fishes were determined by whole-body autoradiography and liquid scintillation spectrometry. The average whole-fish concentration of 63 Ni 2+ in the fishes was about 3 times higher than the concentration of 6 Ni 2+ in the water after 1 week's exposure and about 7-8 times higher than in the water after three weeks' exposure. Our results show that there is a moderate bioaccumulation of nickel by fishes from the water. (author)

Mortality of Juvenile So-iuy Mullet, Liza Haematocheilus (Teleostei, Mugilidae, in the Sea of Azov Associated With Metacercaria (Digenea

Directory of Open Access Journals (Sweden)

Sarabeev V.

2015-12-01

Full Text Available Mortality of Juvenile So-iuy Mullet, Liza haematocheilus (Teleostei, Mugilidae, in the Sea of Azov Associated with Metacercariae (Digenea. Sarabeev, V. - Age-dependent patterns, including yearly variations of digenean metacercariae infestations of the introduced species, Liza haematocheilus (Temminck & Schlegel, 1845, were studied. We evaluated the impacts of three metacercaria species, Timoniella imbutiforme (Molin, 1859 Brooks, 1980, Diplostomum spp. and Ascocotyle (Phagicola longa Ransom, 1920, on juvenile fish in age from one month to 2+ years old from the Molochny Estuary and neighboring waters of the Sea of Azov by applying Croft on’s negative binomial truncation technique, epidemiologic and aggregation indices. Parasite surveys executed in 1997-2014 revealed significant yearly differences in the infection dynamics of studied metacercariae in juvenile fish of L. haematocheilus. Metacercariae were absent or fish harboured several times less parasites in 2005-2013 than in 1997-1999. T. imbutiforme infection exhibits a convex that was observed in a decline of the parasite load aft er an initial increase. The infection load of Diplostomum spp. increased asymptotically with the fish age reaching maximum value in two years old juveniles. Both the abundance and the prevalence of A. (P. longa were low in juveniles of two month and two years old but relatively high and more or less constant during the rest of the juvenile period. Results of the present study suggest that metacercariae, especially, T. imbutiforme, are associated with mortality of juvenile Liza haematocheilus.

Diel foraging and shelter use of large juvenile brown trout (Salmo trutta) under food satiation

DEFF Research Database (Denmark)

Conallin, J.; Jyde, M.; Filrup, K.

2012-01-01

The diel partitioning of juvenile brown trout Salmo trutta foraging behaviour is controlled by a number of factors including predation risk, competition, temperature and food availability. The present study uses PIT-tagging and visual observation to asses the use of shelter and foraging behaviour...... of Danish wild juvenile brown trout (13.5-15.6 cm). The experiment was conducted in a fluvarium and the fish were fed to satiation. It was hypothesised that food satiation would promote nocturnal foraging and increase daytime shelter use. Our results showed a significant difference in diel shelter use...... between day and night with a significant increase in shelter use during daytime conditions. Visual observations showed a significant preference for nocturnal feeding. Together with the significantly reduced shelter use during the night, our results support the hypothesis that young stream living trout...

Recovery of Hafnia alvei from diseased brown trout, Salmo trutta L., and healthy noble crayfish, Astacus astacus (L.), in Bulgaria.

Science.gov (United States)

Orozova, P; Sirakov, I; Chikova, V; Popova, R; Al-Harbi, A H; Crumlish, M; Austin, B

2014-10-01

Hafnia alvei was isolated in Bulgaria from healthy noble crayfish, Astacus astacus (L.), and then from farmed diseased brown trout, Salmo trutta L., with signs of haemorrhagic septicaemia. The isolates were identified initially with conventional phenotyping and commercial Merlin Micronaut and API 20E rapid identification systems, followed by sequencing of the 16S rRNA gene. Hafnia alvei Bt1, Bt2 and Aa4 were of low virulence to rainbow trout and brown trout, although cytotoxicity was demonstrated by Bt1 and Bt2, but not by Aa4. © 2014 John Wiley & Sons Ltd.

Stress of formalin treatment in juvenile spring chinook salmon (Oncorhynchus tshawytscha) and steelhead trout (Salmo gairdneri)

Science.gov (United States)

Wedemeyer, Gary; Yasutake, W.T.

1973-01-01

The physiological stress of 200 ppm formalin treatments at 10 C is more severe in the juvenile steelhead trout (Salmo gairdneri) than in the spring chinook salmon (Oncorhynchus tshawytscha). In the steelhead, a marked hypochloremia follows a 1-hr treatment and recovery requires about 24 hr. During longer treatments, hypercholesterolemia together with reduced regulatory precision, hypercortisolemia, alkaline reserve depletion, and hypocapnia unaccompanied by a fall in blood pH occur — suggestive of compensated respiratory alkalosis. In the spring chinook, hypochloremia and reduced plasma cholesterol regulatory precision are the significant treatment side effects but recovery requires only a few hours.Formalin treatments also cause epithelial separation, hypertrophy, and necrosis in the gills of both fishes but again, consistent with the physiological dysfunctions, these are more severe in the steelhead.

Admixture analysis and stocking impact assessment in brown trout ( Salmo trutta ), estimated with incomplete baseline data

DEFF Research Database (Denmark)

Hansen, Michael Møller; Eg Nielsen, Einar; Bekkevold, Dorte

2001-01-01

the populations contributing to admixture. We applied the method to analyse the genetic contribution of domesticated brown trout (Salmo trutta) in samples of anadromous trout from two stocked populations with no genetic data available before stocking. Further, we estimated population level admixture proportions...... by the mean of individual admixture coefficients. This method proved more informative than a multidimensional scaling analysis of individual-based genetic distances and assignment tests. The results showed almost complete absence of stocked, domesticated trout in samples of trout from the rivers. Consequently......, stocking had little effect on improving fisheries. In one population, the genetic contribution by domesticated trout was small, whereas in the other population, some genetic impact was suggested. Admixture in this sample of anadromous trout despite absence of stocked domesticated trout could be because...

Founder effects and genetic population structure of brown trout (Salmo trutta) in a Danish river system

DEFF Research Database (Denmark)

Hansen, Michael Møller; Mensberg, Karen-Lise Dons

1996-01-01

The influence of founder effects on the genetic population structure of brown trout (Salmo trutta) was studied in a small Danish river system. Samples of trout from seven locations were analysed by allozyme electrophoresis and mitochondrial DNA restriction fragment length polymorphism analysis....... For comparison, allozyme data from other Danish trout populations and mtDNA data from two hatchery strains were included. Genetic differentiation among populations was found to be small but significant. Pairwise tests for homogeneity of allele and haplotype frequencies between samples showed that significance...... simulations of the influence of founder effects on mitochondrial DNA differentiation and variability showed that the observed divergence could be due either to natural founder effects or to a genetic contribution by hatchery trout. However, the allozyme results pointed towards natural founder effects...

Evolution of microhabitat association and morphology in a diverse group of cryptobenthic coral reef fishes (Teleostei: Gobiidae: Eviota)

KAUST Repository

Tornabene, Luke; Ahmadia, Gabby N.; Berumen, Michael L.; Smith, David J.; Jompa, Jamaluddì n; Pezold, Frank L.

2013-01-01

Gobies (Teleostei: Gobiidae) are an extremely diverse and widely distributed group and are the second most species rich family of vertebrates. Ecological drivers are key to the evolutionary success of the Gobiidae. However, ecological and phylogenetic data are lacking for many diverse genera of gobies. Our study investigated the evolution of microhabitat association across the phylogeny of 18 species of dwarfgobies (genus Eviota), an abundant and diverse group of coral reef fishes. In addition, we also explore the evolution of pectoral fin-ray branching and sensory head pores to determine the relationship between morphological evolution and microhabitat shifts. Our results demonstrate that Eviota species switched multiple times from a facultative hard-coral association to inhabiting rubble or mixed sand/rubble habitat. We found no obvious relationship between microhabitat shifts and changes in pectoral fin-ray branching or reduction in sensory pores, with the latter character being highly homoplasious throughout the genus. The relative flexibility in coral-association in Eviota combined with the ability to move into non-coral habitats suggests a genetic capacity for ecological release in contrast to the strict obligate coral-dwelling relationship commonly observed in closely related coral gobies, thus promoting co-existence through fine scale niche partitioning. The variation in microhabitat association may facilitate opportunistic ecological speciation, and species persistence in the face of environmental change. This increased speciation opportunity, in concert with a high resilience to extinction, may explain the exceptionally high diversity seen in Eviota compared to related genera in the family. © 2012 Elsevier Inc.

Transcriptome sequencing of Atlantic salmon (Salmo salar L.) notochord prior to development of the vertebrae provides clues to regulation of positional fate, chordoblast lineage and mineralisation

OpenAIRE

Wang, Shou; Furmanek, Tomasz; Kryvi, Harald; Krossøy, Christel; Totland, Geir Kåre; Grotmol, Sindre; Wargelius, Anna

2014-01-01

Background In teleosts such as Atlantic salmon (Salmo salar L.), segmentation and subsequent mineralisation of the notochord during embryonic stages are essential for normal vertebrae formation. However, the molecular mechanisms leading to segmentation and mineralisation of the notochord are poorly understood. The aim of this study was to identify genes/pathways acting in gradients over time and along the anterior-posterior axis during notochord segmentation and immediately prior to mineralis...

Effect of chlorine toxicity on certain blood parameters of adult rainbow trout (Salmo gairdneri)

Energy Technology Data Exchange (ETDEWEB)

Zeitoun, I.H.

1977-01-01

In an effort to assess the mode of chlorine action on rainbow trout (Salmo gairdneri), hematocrit percentage, and hemoglobin, methemoglobin, reduced glutathione, plasma protein, and plasma hemoglobin concentrations were determined in four tests in which duplicate groups of approximately 15 fish each were exposed to 3.86, 2.47, 2.75, and 1.09 mq l/sup -1/ TRCl/sub 2/ for 8, 19, 20, and 29 minutes, respectively. Blood from fish exposed to chlorine was darker and thicker than that of the control. Chlorine seemed to diffuse readily through the gills, oxidizing the hemoglobin to methemoglobin and disrupting the erythrocyte membranes, resulting in hemolysis. Stress polycythemia was also due to the substantial increase of the hematocrit values and hemoglobin concentration. Hemoconcentration led to a significant rise in the reduced glutathione and plasma protein concentrations. The hemoconcentration seemed to interfere with the blood circulation and hinder the delivery of oxygen to tissues.

Effects of temperature and body size on radiocaesium retention in brown trout, Salmo trutta

International Nuclear Information System (INIS)

Ugedal, O.; Jonsson, B.; Njastad, O.; Naeumann, R.

1992-01-01

The elimination rate of radiocaesium in brown trout Salmo trutta L. was determined in the laboratory at four water temperatures (range 4.4 -15.6 0 C). In the experiments three or four homogeneous size-groups of fish (mean weights 23-496g) were studied at each temperature. The brown trout received acute oral doses of 134 Cs and were killed at intervals for radioactivity counting. The retention versus time curves were composed of two distinct exponential components. The long-lived component was quantitatively the most important for retention of radiocaesium. Elimination rate increased with increasing water temperature and decreased with increasing body weight. The biological half-life of 134 Cs (T b , days) was related to fresh body weight (W, g) and water temperature (t, 0 C) by the equation: T b = 290 x W 0.176 x e -0.106 x t . The elimination rate of Cs could be predicted from weight-specific metabolic rate as given by Elliott's equations for brown trout. (author)

Estructura poblacional y demografía genética en poblaciones de trucha común (Salmo trutta) del Pirineo catalán

OpenAIRE

Fernández Cebrián, Raquel

2012-01-01

El sistema de 9 loci microsatélites desarrollado en este trabajo resulta muy eficiente para el análisis de la estructura poblacional y la demografía genética de las poblaciones de trucha común (Salmo trutta) en las cuencas del Pirineo. La complejidad de los procesos evolutivos ocurridos durante las glaciaciones del cuaternario en el Pirineo y la diferente escala espacial y temporal en que estos han tenido lugar impiden establecer un patrón general que relacione la estructura poblacional y la ...

Preference and avoidance pH of brook trout Salvelinus fontinalis and brown trout Salmo trutta exposed to different holding pH.

Science.gov (United States)

Fost, B A; Ferreri, C P

2015-08-01

The goal of this study was to determine if short-term exposure of brook trout Salvelinus fontinalis and brown trout Salmo trutta to a lower pH than found in their source stream results in a shift in preference or avoidance pH. The lack of a shift in preference or avoidance pH of adult S. fontinalis and S. trutta suggests that these species can be held at a pH different from the source waterbody for a short period of time without altering preference or avoidance pH behaviour. © 2015 The Fisheries Society of the British Isles.

Accelerated recovery of Atlantic salmon (Salmo salar) from effects of crowding by swimming.

Science.gov (United States)

Veiseth, Eva; Fjaera, Svein Olav; Bjerkeng, Bjørn; Skjervold, Per Olav

2006-07-01

The effects of post-crowding swimming velocity (0, 0.35, and 0.70 m/s) and recovery time (1.5, 6, and 12 h) on physiological recovery and processing quality parameters of adult Atlantic salmon (Salmo salar) were determined. Atlantic salmon crowded to a density similar to that of a commercial slaughter process (>200 kg/m(3), 40 min) were transferred to a swimming chamber for recovery treatment. Osmolality and concentrations of cortisol, glucose and lactate in blood plasma were used as physiological stress indicators, whereas image analyses of extent and duration of rigor contraction, and fillet gaping were used as measures of processing quality. Crowded salmon had a 5.8-fold higher plasma cortisol concentration than control salmon (Prigor mortis contraction. However, subjecting crowded salmon to active swimming for 6 h before slaughter delayed the onset of rigor mortis contraction from 2.5 to 7.5 h post mortem. The extent of rigor mortis contraction was also affected by crowding and post-stress swimming activity (Prigor mortis contraction, which has a positive technological implication for the salmon processing industry.

A Dense Brown Trout (Salmo trutta) Linkage Map Reveals Recent Chromosomal Rearrangements in the Salmo Genus and the Impact of Selection on Linked Neutral Diversity

Science.gov (United States)

Leitwein, Maeva; Guinand, Bruno; Pouzadoux, Juliette; Desmarais, Erick; Berrebi, Patrick; Gagnaire, Pierre-Alexandre

2017-01-01

High-density linkage maps are valuable tools for conservation and eco-evolutionary issues. In salmonids, a complex rediploidization process consecutive to an ancient whole genome duplication event makes linkage maps of prime importance for investigating the evolutionary history of chromosome rearrangements. Here, we developed a high-density consensus linkage map for the brown trout (Salmo trutta), a socioeconomically important species heavily impacted by human activities. A total of 3977 ddRAD markers were mapped and ordered in 40 linkage groups using sex- and lineage-averaged recombination distances obtained from two family crosses. Performing map comparison between S. trutta and its sister species, S. salar, revealed extensive chromosomal rearrangements. Strikingly, all of the fusion and fission events that occurred after the S. salar/S. trutta speciation happened in the Atlantic salmon branch, whereas the brown trout remained closer to the ancestral chromosome structure. Using the strongly conserved synteny within chromosome arms, we aligned the brown trout linkage map to the Atlantic salmon genome sequence to estimate the local recombination rate in S. trutta at 3721 loci. A significant positive correlation between recombination rate and within-population nucleotide diversity (π) was found, indicating that selection constrains variation at linked neutral sites in brown trout. This new high-density linkage map provides a useful genomic resource for future aquaculture, conservation, and eco-evolutionary studies in brown trout. PMID:28235829

A Dense Brown Trout (Salmo trutta Linkage Map Reveals Recent Chromosomal Rearrangements in the Salmo Genus and the Impact of Selection on Linked Neutral Diversity

Directory of Open Access Journals (Sweden)

Maeva Leitwein

2017-04-01

Full Text Available High-density linkage maps are valuable tools for conservation and eco-evolutionary issues. In salmonids, a complex rediploidization process consecutive to an ancient whole genome duplication event makes linkage maps of prime importance for investigating the evolutionary history of chromosome rearrangements. Here, we developed a high-density consensus linkage map for the brown trout (Salmo trutta, a socioeconomically important species heavily impacted by human activities. A total of 3977 ddRAD markers were mapped and ordered in 40 linkage groups using sex- and lineage-averaged recombination distances obtained from two family crosses. Performing map comparison between S. trutta and its sister species, S. salar, revealed extensive chromosomal rearrangements. Strikingly, all of the fusion and fission events that occurred after the S. salar/S. trutta speciation happened in the Atlantic salmon branch, whereas the brown trout remained closer to the ancestral chromosome structure. Using the strongly conserved synteny within chromosome arms, we aligned the brown trout linkage map to the Atlantic salmon genome sequence to estimate the local recombination rate in S. trutta at 3721 loci. A significant positive correlation between recombination rate and within-population nucleotide diversity (π was found, indicating that selection constrains variation at linked neutral sites in brown trout. This new high-density linkage map provides a useful genomic resource for future aquaculture, conservation, and eco-evolutionary studies in brown trout.

Combining Radio and PIT-Telemetry to Study the Large and Fine-Scale Movements of Stocked and Wild Brown Trout (Salmo trutta L.) in a Northeastern Stream, Portugal

OpenAIRE

Teixeira, Amílcar A. T.; Cortes, Rui M. V.

2011-01-01

Stream-resident salmonid movements have been the subject of numerous studies and their behaviour is relatively well-known (Harcup et al., 1984; Heggenes, 1988). For example, brown trout (Salmo trutta) is described as a sedentary species based on the behaviour displayed, often associated to the strong site attachment to a territory or home range (Bridcut & Giller, 1993; Armstrong & Herbert, 1997). Other salmonids like brook (Salvelinus fontinalis) (Roghair & Dolloff, 2005) and c...

Feeding of holoshesthes Heterodon eigenmann (Teleostei, Cheirodontinae of the cajuru reservoir (Minas Gerais, Brazil, in relation to the vegetal biomass on its depletion zone

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Márcio Camilo Carvalho Alvim

1998-12-01

Full Text Available Stomach contents of Holoshesthes heterodon Eigenmann, 1915 (Teleostei, Cheirodontinae, collected in the depletion zone of Cajuru reservoir when it was at its maximum water level in two stations with different vegetal densities, were studied in order to investigate the influence of the flooded vegetal biomass on the food quantity and quality ingested by fish. Eighteen individuals from each station were examined. The standard length was l.53±0.05 cm and l.52±0.05 cm, respectively at the lower biomass (8.19 kg diy weight/ha and higher biomass (38.10 kg diy weight/ha sampling stations. The stomach repletion Index (SRI was applied for the quantitative analysis. The alimentary index (IAi was used for the quali-quantitative analysis, with the volume of the items obtained through the points method. SRI did not show values significatively different between the two stations, p>0.05, by applying the Mann-Whitney test. In both situations, Cladocera was the most important item. There were no correlation between the flooded vegetal biomass in the depletion zone and the intake of food by H. heterodon. However, as there were no empty stomachs, possibly even the lower vegetal biomass was enough to provide abundant feeding resources.

Proposed standard-weight (Ws) equation and length-categorization standards for brown trout (Salmo trutta) in lentic habitats

Science.gov (United States)

Hyatt, M.W.; Hubert, W.A.

2001-01-01

We developed a standard-weight (Ws) equation for brown trout (Salmo trutta) in lentic habitats by applying the regression-line-percentile technique to samples from 49 populations in North America. The proposed Ws equation is log10 Ws = -5.422 + 3.194 log10 TL, when Ws is in grams and TL is total length in millimeters. The English-unit equivalent is log10 Ws = -3.592 + 3.194 log10 TL, when Ws is in pounds and TL is total length in inches. The equation is applicable for fish of 140-750 mm TL. Proposed length-category standards to evaluate fish within populations are: stock, 200 mm (8 in); quality, 300 mm (12 in); preferred, 400 mm (16 in); memorable, 500 mm (20 in); and trophy, 600 mm (24 in).

Impact of groundwater abstraction on physical habitat of brown trout (Salmo trutta) in a small Danish stream

DEFF Research Database (Denmark)

Olsen, M.; Bøgh, E.; Pedersen, Stig

2009-01-01

The purpose of this study was to assess the impact of groundwater abstraction on stream discharge and physical habitat conditions for brown trout (Salmo trutta) in a small Danish stream. Stream discharge was simulated using a lumped hydrological model (NAM) and a scenario was set up for stream...... discharge reference conditions. Stream physical habitat conditions (WUA) were simulated for four life stages of trout using a hydraulic habitat model (RHYHABSIM). The impact of groundwater abstraction on WUA for trout was assessed by combined simulations from the NAM-model and the RHYHABSIM-model. The model...... predicted that groundwater abstraction reduced median annual discharge by 37 % and mean annual 90th percentile discharge by 82 %. Summer discharge was relatively most affected by groundwater abstraction (66 % reduction of median discharge) and WUA was therefore particularly affected by groundwater...

Arteriosclerosis in the ventral aorta and epicarditis in the bulbus arteriosus of Atlantic salmon (Salmo salar L).

Science.gov (United States)

Dalum, A S; Kristthorsdottir, K H; Griffiths, D J; Bjørklund, K; Poppe, T T

2017-06-01

Spontaneous mortality of seemingly healthy, farmed Atlantic salmon (Salmo salar L) is an increasing problem in Norwegian aquaculture. In this study, we present a morphological study of the previously undescribed syndrome of arteriosclerosis of the ventral aorta and epicarditis of the adjacent bulbus arteriosus found in farmed Atlantic salmon, with wild-captured fish as a control group. Both the ventral aorta and epicardium are vital for correct arterial compliance and vascular resistance in the respiratory capillaries of the gills. We discuss the possible implications of ventral aorta arteriosclerosis and epicarditis for blood vascular health and in particular for the increasing frequency of spontaneous gill bleeding in farmed salmon. As both these conditions primarily occur in farmed salmon, we suggest that they should be considered pathological. © 2016 John Wiley & Sons Ltd.

On behavioural responses to smell and sight of alpine bullhead Cottus poecilopus Heckel for an allopatric and a sympatric population of brown trout Salmo trutta L.

OpenAIRE

Hauge, Joakim

2007-01-01

Freshwater sculpins and salmonids coexist in many streams throughout the Northern hemisphere, and often constitute an important component of stream ecosystems. Alpine bullhead Cottus poecilopus Heckel have been known to predate eggs and fry of brown trout Salmo trutta L., and also to function as a competitor to older brown trout for habitat and prey items. This study was designed to examine possible behavioural differences in activity level and positioning between a sympatric and an allopatri...

Influence of parental life history on maturation and smoltification in brown trout (Salmo trutta L.

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Dȩbowski Piotr

2016-12-01

Full Text Available The developmental pathways of the offspring of three groups of trout, Salmo trutta L., with known life histories were compared: one group from a freshwater resident population and two groups from an anadromous population (fish that have smoltified and fish that have not. The fish were hybridized within a group, and 27 families were obtained and reared mixed in two tanks. Tracking fish specimens was possible thanks to individual passive integrated transponder (PIT tagging. All families followed different life pathways. Faster growth favored early smoltification and maturation at the age of 1+ in males that had not smoltified. In addition, both processes were clearly also influenced by inherited factors. Fish of freshwater resident origin smoltified more infrequently, and males matured earlier than did fish from the migratory population. The offspring of parents from the migratory population, which did smoltify during their individual histories, smoltified early (in the second year more often than offspring of non-smoltified members of the population.

The significance of water ionic strength on aluminium toxicity in brown trout (Salmo trutta L.)

Energy Technology Data Exchange (ETDEWEB)

Alstad, Nina E.W. [Department of Biology, University of Oslo, P.O. Box 1066 Blindern, N-0316 Oslo (Norway); Kjelsberg, Birgitte M. [Department of Biology, University of Oslo, P.O. Box 1066 Blindern, N-0316 Oslo (Norway); Voellestad, L. Asbjoern [Department of Biology, University of Oslo, P.O. Box 1066 Blindern, N-0316 Oslo (Norway); Lydersen, Espen [Norwegian Institute for Water Research, P.O. Box 173 Kjelsaas, N-0411 Oslo (Norway); Poleo, Antonio B.S. [Department of Biology, University of Oslo, P.O. Box 1066 Blindern, N-0316 Oslo (Norway)]. E-mail: toni.poleo@bio.uio.no

2005-01-01

The toxicity of aluminium to fish is related to interactions between aluminium and the gill surface. We investigated the possible effect of water ionic strength on this interaction. The mortality of brown trout (Salmo trutta L.) exposed to three different degrees of Al polymerisation was compared in water with increased ionic strength (mean 7.31 x 10{sup -4} M) after additions of the base cations Ca{sup 2+}, Mg{sup 2+}, Na{sup +} or K{sup +}, and in water with no such addition (mean ionic strength 5.58 x 10{sup -4} M). Only a very slight ameliorating effect of increased ionic strength was observed, while the degree of Al polymerisation was of major importance in fish mortality. In addition, it was observed that smaller fish survived the Al exposures for a longer time than larger fish. We hypothesise that this is because larger fish are more susceptible to hypoxia than smaller fish. - Ionic strength has a slight ameliorating effect on Al toxicity in brown trout.

The significance of water ionic strength on aluminium toxicity in brown trout (Salmo trutta L.)

International Nuclear Information System (INIS)

Alstad, Nina E.W.; Kjelsberg, Birgitte M.; Voellestad, L. Asbjoern; Lydersen, Espen; Poleo, Antonio B.S.

2005-01-01

The toxicity of aluminium to fish is related to interactions between aluminium and the gill surface. We investigated the possible effect of water ionic strength on this interaction. The mortality of brown trout (Salmo trutta L.) exposed to three different degrees of Al polymerisation was compared in water with increased ionic strength (mean 7.31 x 10 -4 M) after additions of the base cations Ca 2+ , Mg 2+ , Na + or K + , and in water with no such addition (mean ionic strength 5.58 x 10 -4 M). Only a very slight ameliorating effect of increased ionic strength was observed, while the degree of Al polymerisation was of major importance in fish mortality. In addition, it was observed that smaller fish survived the Al exposures for a longer time than larger fish. We hypothesise that this is because larger fish are more susceptible to hypoxia than smaller fish. - Ionic strength has a slight ameliorating effect on Al toxicity in brown trout

Comparison of vegetable shortening and cocoa butter as vehicles for cortisol manipulation in Salmo trutta.

Science.gov (United States)

Birnie-Gauvin, K; Peiman, K S; Larsen, M H; Aarestrup, K; Gilmour, K M; Cooke, S J

2018-01-01

This study demonstrates that vegetable shortening and cocoa butter are two effective vehicles for intraperitoneal cortisol implants in juvenile teleosts, specifically brown trout Salmo trutta, residing in north temperate freshwater environments. Each vehicle showed a different pattern of cortisol elevation. Vegetable shortening was found to be a more suitable vehicle for long-term cortisol elevation [elevated at 3, 6 and 9 days post treatment (dpt)], while cocoa butter may be better suited for short-term cortisol elevation (only elevated at 3 dpt). Additionally, plasma cortisol levels were higher with cortisol-vegetable shortening than with cortisol-cocoa butter implants. Plasma glucose levels were elevated 6 and 9 dpt for fishes injected with cortisol-vegetable shortening, but did not change relative to controls and shams in cortisol-cocoa butter fishes. In conclusion, vegetable shortening and cocoa butter are both viable techniques for cortisol manipulation in fishes in temperate climates, providing researchers with different options depending on study objectives. © 2017 The Fisheries Society of the British Isles.

Patterns of natural mortality in stream-living brown trout (Salmo trutta)

Science.gov (United States)

Lobon-Cervia, J.; Budy, P.; Mortensen, E.

2012-01-01

We tested the hypothesis that lifetime mortality patterns and their corresponding rates and causal factors differ among populations of stream-living salmonids. To this end, we examined the lifetime mortality patterns of several successive cohorts of two stream-living brown trout (Salmo trutta) populations in Spain and Denmark. In the southern population, we observed a consistent two-phase pattern, in which mortality was negligible during the first half of the lifetime and severe during the rest of the lifetime. In contrast, the northern population demonstrated a three-phase pattern with an earlier phase varying from negligible to severe, followed by a second stage of weak mortality, and lastly by a third life stage of severe mortality. Despite substantial differences in the mortality patterns between the two populations, the combined effect of recruitment (as a proxy of the density-dependent processes occurring during the lifetime) and mean body mass (as a proxy of growth experienced by individuals in a given cohort) explained c. 89% of the total lifetime mortality rates across cohorts and populations. A comparison with other published data on populations of stream-living brown trout within its native range highlighted lifetime mortality patterns of one, two, three and four phases, but also suggested that common patterns may occur in populations that experience similar individual growth and population density. ?? 2011 Blackwell Publishing Ltd.

Simultaneous analysis of five molecular markers provides a well-supported phylogenetic hypothesis for the living bony-tongue fishes (Osteoglossomorpha: Teleostei).

Science.gov (United States)

Lavoué, Sébastien; Sullivan, John P

2004-10-01

Fishes of the Superorder Osteoglossomorpha (the "bonytongues") constitute a morphologically heterogeneous group of basal teleosts, including highly derived subgroups such as African electric fishes, the African butterfly fish, and Old World knifefishes. Lack of consensus among hypotheses of osteoglossomorph relationships advanced during the past 30 years may be due in part to the difficulty of identifying shared derived characters among the morphologically differentiated extant families of this group. In this study, we present a novel phylogenetic hypothesis for this group, based on the analysis of more than 4000 characters from five molecular markers (the mitochondrial cytochrome b, 12S and 16S rRNA genes, and the nuclear genes RAG2 and MLL). Our taxonomic sampling includes one representative of each extant non-mormyrid osteoglossomorph genus, one representative for the monophyletic family Mormyridae, and four outgroup taxa within the basal Teleostei. Maximum parsimony analysis of combined and equally weighted characters from the five molecular markers and Bayesian analysis provide a single, well-supported, hypothesis of osteoglossomorph interrelationships and show the group to be monophyletic. The tree topology is the following: (Hiodon alosoides, (Pantodon buchholzi, (((Osteoglossum bicirrhosum, Scleropages sp.), (Arapaima gigas, Heterotis niloticus)), ((Gymnarchus niloticus, Ivindomyrus opdenboschi), ((Notopterus notopterus, Chitala ornata), (Xenomystus nigri, Papyrocranus afer)))))). We compare our results with previously published phylogenetic hypotheses based on morpho-anatomical data. Additionally, we explore the consequences of the long terminal branch length for the taxon Pantodon buchholzi in our phylogenetic reconstruction and we use the obtained phylogenetic tree to reconstruct the evolutionary history of electroreception in the Notopteroidei.

Tetracapsuloides bryosalmonae persists in brown trout Salmo trutta for five years post exposure.

Science.gov (United States)

Soliman, Hatem; Kumar, Gokhlesh; El-Matbouli, Mansour

2018-01-31

Tetracapsuloides bryosalmonae is a malacosporean parasite and the causative agent of proliferative kidney disease (PKD) that seriously impacts farmed and wild salmonids. The parasite's life cycle includes an invertebrate host, the bryozoan Fredericella sultana, and a vertebrate host, salmonid fish. The persistence of T. bryosalmonae in brown trout Salmo trutta for up to 2 yr following exposure is well documented. Results from the present study confirmed that one brown trout that had recovered from PKD did not completely clear the parasite from its tissues and that T. bryosalmonae could persist in brown trout for up to 5 yr post exposure. Furthermore, recovered infected brown trout can release viable T. bryosalmonae spores that are able to infect specific pathogen-free F. sultana colonies. T. bryosalmonae DNA was detected by PCR in every organ, and parasite stages were observed in the kidney, spleen and liver following immunohistochemistry. This finding indicates that T. bryosalmonae-infected brown trout can act as asymptomatic carriers and release the parasite for several years after the initial infection, acting as a reservoir of infection, and contributing to the dissemination of the parasite to new areas.

Studies on the metabolism of astaxanthin in the rainbow trout (Salmo gairdneri)

International Nuclear Information System (INIS)

Al-Khalifah, A.S.

1986-01-01

Racemic astaxanthin was fed to rainbow trout (Salmo gairdneri) for 2, 4, and 6 weeks. The fish showed a bright pink coloration of the skin and flesh; the highest amount of astaxanthin was found in the skin of fish fed the test diet for six weeks. Lutein, 3-epilutein, and zeaxanthin were also detected in the flesh and skin; it was concluded that astaxanthin was converted to zeaxanthin in the skin. The mean vitamin A content of the liver was determined; the ratio of vitamin A 1 :vitamin A 2 was approximately 1:3. Retinol and 3,4-dehydroretinol were extracted from the intestine of rainbow trout low in vitamin A, after force feeding with astaxanthin using a feeding tube. Antibiotic-treated fish had no marked difference in vitamin A content compared with a control group that received no antibiotic. This proves that astaxanthin was converted to vitamin A in fish depleted of vitamin A, that microorganisms were not involved in the conversion, and that conversion occurred in the intestine. An in vitro study using 3 H 3S, 3S'-astaxanthin incubated with duodenal and ileal segments of the intestine provided HLPC and radioisotope data, which showed that rainbow trout were able to bioconvert astaxanthin to vitamin A

Plerocercoids of the cestode Diphyllobothrium ditremum in brown trout Salmo trutta: substantial increase in infection after establishment of European minnow Phoxinus phoxinus.

Science.gov (United States)

Borgstrøm, R; Trømborg, J; Haugen, T O; Rosseland, B O

2017-09-01

This study focuses on plerocercoids of the cestode Diphyllobothrium ditremum in brown trout Salmo trutta from the subalpine lake Øvre Heimdalsvatn in south-central Norway. Salmo trutta was the only fish species in this lake until European minnow Phoxinus phoxinus was registered in 1969. The P. phoxinus population increased substantially in the following years. In contrast with the 1969-1972 period, when plerocercoids of D. ditremum were practically absent in S. trutta, there was a high prevalence and intensity of infection in the 2013 S. trutta samples. Because the life cycle of D. ditremum involves two larval stages, in copepods and salmonids and mature worms in piscivorous birds, such as mergansers and loons, a change in feeding ecology of S. trutta or changes in population densities of copepods, fish or birds might have influenced the infection pattern. No relationships between D. ditremum infection and muscle-tissue δ 15 N signature or Hg concentration were found, indicating that infection is not a result of piscivory or cannibalism. Furthermore, consumption of copepods by S. trutta during summer and autumn was low. On the other hand, the number of piscivorous birds has increased, probably due to the presence of P. phoxinus as a new and numerous prey. An increased number of final D. ditremum hosts may have produced a higher output of cestode eggs, resulting in more infected copepods that in turn are consumed by S. trutta. Indirectly, P. phoxinus may therefore have caused the observed increased infection in S. trutta and thereby imposed further negative effects on S. trutta in high mountain areas. © 2017 The Fisheries Society of the British Isles.

The effect of Cu (II) on the electro-olfactogram (EOG) of the Atlantic salmon (Salmo salar L) in artificial freshwater of varying inorganic carbon concentrations

DEFF Research Database (Denmark)

Winberg, S; Bjerselius, R; Baatrup, E

1993-01-01

The effect of inorganic copper species was studied by recording the receptor potential, electro-olfactogram (EOG), from the olfactory epithelium of Atlantic salmon (Salmo salar L). In a series of experiments, the olfactory organ was irrigated with aqueous copper solutions with concentrations...... of the free cupric ion (Cu2+) ranging from 0.2 to 9.7 microM. The diverse copper species were created by varying the amount of bicarbonate (NaHCO3) in artificial freshwater solutions of equal total copper concentrations. In general, these copper solutions induced a slow depolarization of the baseline followed...

Genetic variation in threshold reaction norms for alternative reproductive tactics in male Atlantic salmon, Salmo salar.

Science.gov (United States)

Piché, Jacinthe; Hutchings, Jeffrey A; Blanchard, Wade

2008-07-07

Alternative reproductive tactics may be a product of adaptive phenotypic plasticity, such that discontinuous variation in life history depends on both the genotype and the environment. Phenotypes that fall below a genetically determined threshold adopt one tactic, while those exceeding the threshold adopt the alternative tactic. We report evidence of genetic variability in maturation thresholds for male Atlantic salmon (Salmo salar) that mature either as large (more than 1 kg) anadromous males or as small (10-150 g) parr. Using a common-garden experimental protocol, we find that the growth rate at which the sneaker parr phenotype is expressed differs among pure- and mixed-population crosses. Maturation thresholds of hybrids were intermediate to those of pure crosses, consistent with the hypothesis that the life-history switch points are heritable. Our work provides evidence, for a vertebrate, that thresholds for alternative reproductive tactics differ genetically among populations and can be modelled as discontinuous reaction norms for age and size at maturity.

Effects of passive integrated transponder tags on survival and growth of juvenile Atlantic salmon Salmo salar

DEFF Research Database (Denmark)

Larsen, Martin Hage; Thorn, Aske N.; Skov, Christian

2013-01-01

Background: A laboratory experiment was conducted to assess the potential impacts of surgically implanted 23 and 32 mm passive integrated transponder (PIT) tags on survival, growth, and body condition of juvenile Atlantic salmon Salmo salar. Rate of tag retention and healing of the tagging incision...... were also evaluated. Atlantic salmon of three different size classes (I: 80 to 99 mm fork length (FL), II: 100 to 119 mm FL, III: 120 to 135 mm FL) were allocated to each of five experimental treatment groups: control, sham-operated (surgery without PIT-tag implantation), 23 mm PIT-tag implantation...... with and without suture closure of the incision, and 32 mm PIT-tag implantation without suture closure. Results: Over the 35-day experiment, mortality occurred only among fish tagged with 32 mm PIT tags (14%) and all fish larger than 103 mm FL survived. Non-sutured Atlantic salmon between 80 and 99 mm FL implanted...

Identification of Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss) by using polymerase chain reaction amplification and restriction analysis of the mitochondrial cytochrome b gene.

Science.gov (United States)

Carrera, E; García, T; Céspedes, A; González, I; Sanz, B; Hernández, P E; Martín, R

1998-04-01

Restriction site analysis of polymerase chain reaction (PCR) products from a conserved region of the cytochrome b gene has been used for the identification of fresh and smoked samples of Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss). Digestion of the 359-bp PCR product with the endonucleases EcoRV and TaqI yielded specific banding patterns for salmon and trout. This genetic marker can be very useful for detecting fraudulent substitution of the cheaper smoked trout for the more expensive smoked salmon.

Supplementing a commercial diet for atlantic salmon (Salmo salar L.) with arginine, glutamate or tetradecylthioacetic acid (TTA). impact on production efficiency, slaughter parameters and flesh quality

OpenAIRE

Rahnama, Behzad

2010-01-01

The present study was carried out to evaluate the effects of supplementing a commercial diets with 1.5% L-arginine, 1.5% L-glutamate or 0.25% tetradecylthioacetic acid (TTA) on feed intake, feed utilization and growth parameters of Atlantic salmon (Salmo salar L.) during the critical periods after sea transfer with regard to seawater adaptation and onwards, from April to September. In the case of TTA, fish were fed until they reached a weight gain of 0.2% of the initial body weight, thereafte...

Seasonal Variations in Relative Weight of Lake Trout (Salvelinus namaycush), Kokanee Salmon (Oncorhynchus nerka), Rainbow Trout (Onocorhynchus mykiss), and Brown Trout (Salmo trutta) in Blue Mesa Reservoir, Colorado

OpenAIRE

Midas, Madeline; Williams, Asia; Cooper, Cindy; Courtney, Michael

2013-01-01

Blue Mesa Reservoir is the largest body of water in Colorado and is located on the western slope of the Rocky Mountains at an elevation of 7520 feet. Blue Mesa Reservoir contains recreationally important populations of lake trout (Salvelinus namaycush), kokanee salmon (Oncorhynchus nerka), rainbow trout (Onocorhynchus mykiss), and brown trout (Salmo trutta). A management challenge in recent years has been the overpopulation of lake trout, which has led to a steep decline in abundance of kokan...

Effects of TLR agonists and viral infection on cytokine and TLR expression in Atlantic salmon (Salmo salar).

Science.gov (United States)

Arnemo, Marianne; Kavaliauskis, Arturas; Gjøen, Tor

2014-10-01

The development of efficient and cheap vaccines against several aquatic viruses is necessary for a sustainable fish farming industry. Toll-like receptor (TLR) ligands have already been used as good adjuvants in human vaccines. With more understanding of TLR expression, function, and ligand specificity in fish, more efficient adjuvants for fish viral vaccines can be developed. In this paper, we examine all known TLRs in Atlantic salmon (Salmo salar) and demonstrate that head kidney and spleen are the main organs expressing TLRs in salmon. We also show that adherent head kidney leucocytes from salmon are able to respond to many of the known agonists for human TLRs, and that viral infection can induce up-regulation of several TLRs. These findings substantiate these receptors' role in immune responses to pathogens in salmonids making their ligands attractive as vaccine adjuvant candidates. Copyright © 2014 Elsevier Ltd. All rights reserved.

Future migratory behaviour predicted from premigratory levels of gill Na+/K(+-)ATPase activity in individual wild brown trout ( Salmo trutta )

DEFF Research Database (Denmark)

Nielsen, C.; Aarestrup, Kim; Norum, U.

2004-01-01

The relationship between premigratory gill Na+/K(+-)ATPase activity, determined at two dates during spring, and future migratory behaviour was investigated using non-lethal gill biopsies and PIT-tagging in wild brown trout (Salmo trutta) from two tributaries. No significant relationship between......(-1)), with an average of 91 % of the predictions being correct. The present study shows that a non-lethal premigratory biochemical measurement can successfully select individual brown trout with high probability of migration...... was obtained. The ability of this regression model from the tributaries to predict future migratory behaviour in an independent group of trout caught in early April in the mainstream was evaluated. A threshold probability of migration was used to predict the behaviour of the mainstream individuals as either...

Interpopulation differences in expression of candidate genes for salinity tolerance in winter migrating anadromous brown trout ( Salmo trutta L.)

DEFF Research Database (Denmark)

Larsen, Peter Foged; Eg Nielsen, Einar; Koed, Anders

2008-01-01

Background: Winter migration of immature brown trout (Salmo trutta) into freshwater rivers has been hypothesized to result from physiologically stressful combinations of high salinity and low temperature in the sea. Results: We sampled brown trout from two Danish populations entering different...... conditions in the sea drive sea-run brown trout into freshwater rivers in winter. However, our results also demonstrate intra-specific differences in expression of important stress and osmoregulative genes most likely reflecting adaptive differences between trout populations on a regional scale, thus...... was found in trout from the river entering high saline conditions, while a temperature independent up-regulation of both genes in full-strength seawater was found for trout entering marine conditions with lower salinities. Conclusion: Overall our results support the hypothesis that physiologically stressful...

Early enrichment effects on brain development in hatchery-reared Atlantic salmon (Salmo salar): no evidence for a critical period

DEFF Research Database (Denmark)

Näslund, Joacim; Aarestrup, Kim; Thomassen, Søren T.

2012-01-01

was released into nature and recaptured at smoltification. These stream-reared smolts developed smaller brains than the hatchery reared smolts, irrespective of initial enrichment treatment. These novel findings do not support the hypothesis that there is a critical early period determining the brain growth...... trajectory. In contrast, our results indicate that brain growth is plastic in relation to environment. In addition, we show allometric growth in brain substructures over juvenile development, which suggests that comparisons between groups of different body size should be made with caution. These results can......In hatcheries, fish are normally reared in barren environments, which have been reported to affect their phenotypic development compared with wild conspecifics. In this study, Atlantic salmon (Salmo salar) alevins were reared in conventional barren hatchery trays or in either of two types...

Ichthyobodo salmonis sp. n. (Ichthyobodonidae, Kinetoplastida), an euryhaline ectoparasite infecting Atlantic salmon (Salmo salar L.)

Science.gov (United States)

ISAKSEN, TROND E.; KARLSBAKK, EGIL; WATANABE, KUNINORI; NYLUND, ARE

2011-01-01

SUMMARY Phylogenetic analyses of SSU rDNA sequences have previously revealed the existence of 2 Ichthyobodo species able to infect Atlantic salmon (Salmo salar L.). Ichthyobodo necator sensu stricto (s.s.) is assumed to be a freshwater parasite, while a genetically distinct but undescribed species, Ichthyobodo sp. II sensu Todal et al. (2004) have been detected on Atlantic salmon in both fresh- and seawater. In the present study a morphological description of Ichthyobodo sp. II from the gills of salmon reared in fresh-, brackish- and seawater is presented, using both light- and electron microscopy. Comparative morphometry show that Ichthyobodo sp. II from both freshwater and seawater displays a different cell shape, and is significantly smaller than I. necator s.s. Also, ultrastructural characteristics distinguish these two species, notably differences in the attachment region and the presence of spine-like surface projections in Ichthyobodo sp. II. Based on both unique SSU rDNA sequences and morphological characteristics, we conclude that Ichthyobodo sp. II. represents a novel species for which we propose the name Ichthyobodo salmonis sp. n. PMID:21756424

Influence of fluoride on aluminum toxicity to Atlantic salmon (Salmo salar)

Science.gov (United States)

Hamilton, Steven J.; Haines, Terry A.

1995-01-01

Atlantic salmon (Salmo salar) alevins were exposed to various aluminum (0–4700 μg/L) and four fluoride (0–500 μg/L) concentrations at two pH values (5.5 and 6.5) for 4- and 30-d periods. In the 4-d tests, aluminum with fluoride was less toxic at pH 6.5 than at pH 5.5, whereas without fluoride, pH had no effect. In the 30-d test, mortality in all treatments was 17–21% at pH 5.5, but only 3–7% at pH 6.5. Fish length and weight after 30 d were reduced in all fluoride–aluminum treatments at pH 5.5, but only in the 200-μg/L aluminum without fluoride treatment at pH 6.5. At pH 5.5 and 6.5 without aluminum, histomorphological examinations revealed no abnormalities in gill tissue. However, in aluminum exposure with no fluoride, gill filaments and secondary lamellae were swollen and thickened. Addition of fluoride at pH 6.5 alleviated some gill damage. At pH 5.5 and 200 μg/L aluminum, addition of 100 μg/L fluoride reduced swelling of gill lamellae, but 200 μg/L fluoride did not reduce swelling. Low fluoride concentrations (fluoride concentrations (> 100 μg/L) may not reduce aluminum-induced effects.

Future migratory behaviour predicted from premigratory levels of gill Na⁺/K⁺-ATPase activity in individual wild brown trout (Salmo trutta)

DEFF Research Database (Denmark)

Nielsen, Christian; Aarestrup, Kim; Nørum, Ulrik

2004-01-01

The relationship between premigratory gill Na+/K+-ATPase activity, determined at two dates during spring, and future migratory behaviour was investigated using non-lethal gill biopsies and PIT-tagging in wild brown trout (Salmo trutta) from two tributaries. No significant relationship between...... future migrants or residents. The maximum percentage of correct predictions of future migratory behaviour in mainstream fish was observed at threshold probabilities between approximately 0.15 and 0.45 (corresponding to threshold gill Na+/K+-ATPase activities between 2.7 and 3.7 micromol ADP mg-1 protein...

Consistent melanophore spot patterns allow long-term individual recognition of Atlantic salmon Salmo salar.

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Stien, L H; Nilsson, J; Bui, S; Fosseidengen, J E; Kristiansen, T S; Øverli, Ø; Folkedal, O

2017-12-01

The present study shows that permanent melanophore spot patterns in Atlantic salmon Salmo salar make it possible to use images of the operculum to keep track of individual fish over extended periods of their life history. Post-smolt S. salar (n = 246) were initially photographed at an average mass of 98 g and again 10 months later after rearing in a sea cage, at an average mass of 3088 g. Spots that were present initially remained and were the most overt (largest) 10 months later, while new and less overt spots had developed. Visual recognition of spot size and position showed that fish with at least four initial spots were relatively easy to identify, while identifying fish with less than four spots could be challenging. An automatic image analysis method was developed and shows potential for fast match processing of large numbers of fish. The current findings promote visual recognition of opercular spots as a welfare-friendly alternative to tagging in experiments involving salmonid fishes. © The Authors. Journal of Fish Biology published by John Wiley & Sons Ltd on behalf of The Fisheries Society of the British Isles.

Persistence of Tetracapsuloides bryosalmonae (Myxozoa) in chronically infected brown trout Salmo trutta.

Science.gov (United States)

Abd-Elfattah, Ahmed; Kumar, Gokhlesh; Soliman, Hatem; El-Matbouli, Mansour

2014-08-21

Proliferative kidney disease (PKD) is a widespread disease of farmed and wild salmonid populations in Europe and North America, caused by the myxozoan parasite Tetracapsuloides bryosalmonae. Limited studies have been performed on the epidemiological role in spread of the disease played by fish that survive infection with T. bryosalmonae. The aim of the present study was to evaluate the persistence of T. bryosalmonae developmental stages in chronically infected brown trout Salmo trutta up to 2 yr after initial exposure to laboratory-infected colonies of the parasite's alternate host, the bryozoan Fredericella sultana. Kidney, liver, spleen, intestine, brain, gills and blood were sampled 24, 52, 78 and 104 wk post-exposure (wpe) and tested for T. bryosalmonae by PCR and immunohistochemistry (IHC). Cohabitation trials with specific pathogen free (SPF) F. sultana colonies were conducted to test the viability of T. bryosalmonae. PCR detected T. bryosalmonae DNA in all tissue samples collected at the 4 time points. Developmental stages of T. bryosalmonae were demonstrated by IHC in most samples at the 4 time points. Cohabitation of SPF F. sultana with chronically infected brown trout resulted in successful transmission of T. bryosalmonae to the bryozoan. This study verified the persistence of T. bryosalmonae in chronically infected brown trout and their ability to infect the bryozoan F. sultana up to 104 wpe.

Phylogenetic status of brown trout Salmo trutta populations in five rivers from the southern Caspian Sea and two inland lake basins, Iran: a morphogenetic approach.

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Hashemzadeh Segherloo, I; Farahmand, H; Abdoli, A; Bernatchez, L; Primmer, C R; Swatdipong, A; Karami, M; Khalili, B

2012-10-01

Interrelationships, origin and phylogenetic affinities of brown trout Salmo trutta populations from the southern Caspian Sea basin, Orumieh and Namak Lake basins in Iran were analysed from complete mtDNA control region sequences, 12 microsatellite loci and morphological characters. Among 129 specimens from six populations, seven haplotypes were observed. Based on mtDNA haplotype data, the Orumieh and southern Caspian populations did not differ significantly, but the Namak basin-Karaj population presented a unique haplotype closely related to the haplotypes of the other populations (0·1% Kimura two-parameter, K2P divergence). All Iranian haplotypes clustered as a distinct group within the Danube phylogenetic grouping, with an average K2P distance of 0·41% relative to other Danubian haplotypes. The Karaj haplotype in the Namak basin was related to a haplotype (Da26) formerly identified in the Tigris basin in Turkey, to a Salmo trutta oxianus haplotype from the Aral Sea basin, and to haplotype Da1a with two mutational steps, as well as to other Iranian haplotypes with one to two mutational steps, which may indicate a centre of origin in the Caspian basin. In contrast to results of the mtDNA analysis, more pronounced differentiation was observed among the populations studied in the morphological and microsatellite DNA data, except for the two populations from the Orumieh basin, which were similar, possibly due to anthropogenic causes. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

The abundance of large, piscivorous Ferox Trout (Salmo trutta in Loch Rannoch, Scotland

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Alastair Thorne

2016-11-01

Full Text Available Background Ferox Trout are large, long-lived piscivorous Brown Trout (Salmo trutta. Due to their exceptionally large size, Ferox Trout are highly sought after by anglers while their life-history strategy, which includes delayed maturation, multiphasic growth and extended longevity, is of interest to ecological and evolutionary modelers. However, despite their recreational and theoretical importance, little is known about the typical abundance of Ferox Trout. Methods To rectify this situation a 16 year angling-based mark-recapture study was conducted on Loch Rannoch, which at 19 km2 is one of the largest lakes in the United Kingdom. Results A hierarchical Bayesian Jolly-Seber analysis of the data suggest that if individual differences in catchability are negligible the population of Ferox Trout in Loch Rannoch in 2009 was approximately 71 fish. The results also suggest that a single, often unaccompanied, highly-experienced angler was able to catch roughly 8% of the available fish on an annual basis. Discussion It is recommended that anglers adopt a precautionary approach and release all trout with a fork length ≥400 mm caught by trolling in Loch Rannoch. There is an urgent need to assess the status of Ferox Trout in other lakes.

Genome-wide methylation study of diploid and triploid brown trout (Salmo trutta L.).

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Covelo-Soto, L; Leunda, P M; Pérez-Figueroa, A; Morán, P

2015-06-01

The induction of triploidization in fish is a very common practice in aquaculture. Although triploidization has been applied successfully in many salmonid species, little is known about the epigenetic mechanisms implicated in the maintenance of the normal functions of the new polyploid genome. By means of methylation-sensitive amplified polymorphism (MSAP) techniques, genome-wide methylation changes associated with triploidization were assessed in DNA samples obtained from diploid and triploid siblings of brown trout (Salmo trutta). Simple comparative body measurements showed that the triploid trout used in the study were statistically bigger, however, not heavier than their diploid counterparts. The statistical analysis of the MSAP data showed no significant differences between diploid and triploid brown trout in respect to brain, gill, heart, liver, kidney or muscle samples. Nonetheless, local analysis pointed to the possibility of differences in connection with concrete loci. This is the first study that has investigated DNA methylation alterations associated with triploidization in brown trout. Our results set the basis for new studies to be undertaken and provide a new approach concerning triploidization effects of the salmonid genome while also contributing to the better understanding of the genome-wide methylation processes. © 2015 Stichting International Foundation for Animal Genetics.

Biological variation of lipid constituents and distribution of tocopherols and astaxanthin in farmed Atlantic salmon (Salmo salar)

DEFF Research Database (Denmark)

Refsgaard, Hanne; Brockhoff, Per B; Jensen, Benny

1998-01-01

The contents of fat, astaxanthin, and tocogherols and the fatty acid composition of a homogeneous group of 145 farmed Atlantic salmon (Salmo salar) were determined. The analytical variation of the data was stastistically-separated from the biological variation. The fat content in the muscle near...... the head was 15.0% with a biological standard deviation of 3.0%. The astaxanthin concentration was 5.5 mg/kg of muscle with a biological standard deviation of 1.1 mg/kg of muscle, and the canthaxanthin concentration was 200 mu g/kg of muscle with a standard deviation of 47 mu g/kg of muscle....... The concentrations of alpha-, gamma-, and delta-tocopherols were approximately 32, 2.9, and 0.4 mg/kg of muscle, respectively, and the biological standard deviations were 4.5, 0.4, and 0.07 mg/kg (14, 14, and 20%), respectively. in another group of five salmon the distributions throughout the fillet were determined...

Ectoparasite Caligus rogercresseyi modifies the lactate response in Atlantic salmon (Salmo salar) and Coho salmon (Oncorhynchus kisutch).

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Vargas-Chacoff, L; Muñoz, J L P; Hawes, C; Oyarzún, R; Pontigo, J P; Saravia, J; González, M P; Mardones, O; Labbé, B S; Morera, F J; Bertrán, C; Pino, J; Wadsworth, S; Yáñez, A

2017-08-30

Although Caligus rogercresseyi negatively impacts Chilean salmon farming, the metabolic effects of infection by this sea louse have never been completely characterized. Therefore, this study analyzed lactate responses in the plasma, as well as the liver/muscle lactate dehydrogenase (LDH) activity and gene expression, in Salmo salar and Oncorhynchus kisutch infested by C. rogercresseyi. The lactate responses of Atlantic and Coho salmon were modified by the ectoparasite. Both salmon species showed increasing in plasma levels, whereas enzymatic activity increased in the muscle but decreased in the liver. Gene expression was overexpressed in both Coho salmon tissues but only in the liver for Atlantic salmon. These results suggest that salmonids need more energy to adapt to infection, resulting in increased gene expression, plasma levels, and enzyme activity in the muscles. The responses differed between both salmon species and over the course of infection, suggesting potential species-specific responses to sea-lice infection. Copyright © 2017 Elsevier B.V. All rights reserved.

Dietary linoleic acid elevates endogenous 2-arachidonoylglycerol and anandamide in Atlantic salmon (Salmo salar L.) and mice, and induces weight gain and inflammation in mice

DEFF Research Database (Denmark)

Alvheim, Anita R.; Torstensen, Bente E.; Lin, Yu Hong

2013-01-01

, arachidonic acid (AA), decreased EPA and DHA, elevated the endocannabinoids 2-arachidonoylglycerol (2-AG) and anandamide (AEA), and increased TAG accumulation in the salmon liver. In mice, the SO salmon diet increased LA and AA and decreased EPA and DHA in the liver and erythrocyte phospholipids, and elevated......Dietary intake of linoleic acid (LA) has increased dramatically during the twentieth century and is associated with a greater prevalence of obesity. Vegetable oils are recognised as suitable alternatives to fish oil (FO) in feed for Atlantic salmon (Salmo salar L.) but introduce high amounts of LA......-inflammatory properties of EPA and DHA in mice....

Short-and long term niche segregation and individual specialization of brown trout (Salmo trutta) in species poor Faroese lakes

DEFF Research Database (Denmark)

Brodersen, Jakob; Malmquist, Hilmar J.; Landkildehus, Frank

2012-01-01

fidelity to a niche may be variable both between and within populations. In order to study this complexity, relative simple systems with few species are needed. In this paper, we study how competitor presence affects the resource use of brown trout (Salmo trutta) in 11 species-poor Faroese lakes...... by comparing relative abundance, stable isotope ratios and diet in multiple habitats. In the presence of three-spined sticklebacks (Gasterosteus aculeatus), a higher proportion of the trout population was found in the pelagic habitat, and trout in general relied on a more pelagic diet base as compared to trout...... living in allopatry or in sympatry with Arctic charr (Salvelinus alpinus). Diet analyses revealed, however, that niche-segregation may be more complex than described on a one-dimensional pelagic-littoral axis. Trout from both littoral and offshore benthic habitats had in the presence of sticklebacks...

Influencia del α-tocoferol en la incorporación y peroxidación del ácido araquidónico en alevines parr de salmón del Atlántico (Salmo salar L. Influence of α-tocopherol on arachidonic acid deposition and peroxidation in Atlantic salmon (Salmo salar L. fingerlings

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Patricio Dantagnan

2012-09-01

Full Text Available Se evaluó el efecto sinérgico del ácido araquidónico (ARA (20:4n-6 y el α-tocoferol en la acumulación de estos nutrientes y su peroxidación en el músculo e hígado en juveniles de salmón del Atlántico (Salmo salar. Grupos por triplicado se alimentaron por 12 semanas con ocho dietas experimentales que contenían diferentes niveles de ácido araquidónico y α-tocoferol. Los parámetros productivos no se vieron afectados (P > 0,05 por las dietas suministradas. La acumulación del ARA en el músculo e hígado mostró diferencias significativas (P The synergistic effect of arachidonic acid (ARA (20:4n-6 and α-tocopherol on the accumulation of fatty acids and the peroxidation of lipids in liver and muscle was evaluated in Atlantic salmon (Salmo salar juveniles. Triplicate groups were fed during 12 weeks with eight experimental diets with different levels of ARA and α-tocopherol. In all experimental diets the productive parameters were not affected (P > 0.05. ARA accumulation in muscle and liver showed significant differences (P < 0.05 between treatments. The synergic relationship between ARAAx4ocopherol was influenced (P < 0.05 only in the liver, showing that high levels of α-tocopherol and ARA favored the fatty acids accumulation in this organ. Results indicate that a dietary concentration up to 0.6% ARA, the increment of α-tocopherol is not necessary. The data obtained in this study demonstrated that the interaction between the ARA and α-tocopherol influenced the accumulation of fatty acids in the liver.

AFRREV STECH, Vol. 1 (3) August-December, 2012

African Journals Online (AJOL)

First Lady

Because of the high food fish value of Chrysichthys nigrodigitatus. (Ezenwa, 1988 ... (fresh water) has been the constant presence of post larva and the presence of female with ripe ..... Fecundity of north American Salmonidae. U.S. fish. Wildl.

Phylogeny and biogeography of highly diverged freshwater fish species (Leuciscinae, Cyprinidae, Teleostei) inferred from mitochondrial genome analysis.

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Imoto, Junichi M; Saitoh, Kenji; Sasaki, Takeshi; Yonezawa, Takahiro; Adachi, Jun; Kartavtsev, Yuri P; Miya, Masaki; Nishida, Mutsumi; Hanzawa, Naoto

2013-02-10

The distribution of freshwater taxa is a good biogeographic model to study pattern and process of vicariance and dispersal. The subfamily Leuciscinae (Cyprinidae, Teleostei) consists of many species distributed widely in Eurasia and North America. Leuciscinae have been divided into two phyletic groups, leuciscin and phoxinin. The phylogenetic relationships between major clades within the subfamily are poorly understood, largely because of the overwhelming diversity of the group. The origin of the Far Eastern phoxinin is an interesting question regarding the evolutionary history of Leuciscinae. Here we present phylogenetic analysis of 31 species of Leuciscinae and outgroups based on complete mitochondrial genome sequences to clarify the phylogenetic relationships and to infer the evolutionary history of the subfamily. Phylogenetic analysis suggests that the Far Eastern phoxinin species comprised the monophyletic clades Tribolodon, Pseudaspius, Oreoleuciscus and Far Eastern Phoxinus. The Far Eastern phoxinin clade was independent of other Leuciscinae lineages and was closer to North American phoxinins than European leuciscins. All of our analysis also suggested that leuciscins and phoxinins each constituted monophyletic groups. Divergence time estimation suggested that Leuciscinae species diverged from outgroups such as Tincinae to be 83.3 million years ago (Mya) in the Late Cretaceous and leuciscin and phoxinin shared a common ancestor 70.7 Mya. Radiation of Leuciscinae lineages occurred during the Late Cretaceous to Paleocene. This period also witnessed the radiation of tetrapods. Reconstruction of ancestral areas indicates Leuciscinae species originated within Europe. Leuciscin species evolved in Europe and the ancestor of phoxinin was distributed in North America. The Far Eastern phoxinins would have dispersed from North America to Far East across the Beringia land bridge. The present study suggests important roles for the continental rearrangements during the

Ligophorus spp. (Monogenoidea: Dactylogyridae) parasitizing mullets (Teleostei: Mugiliformes: Mugilidae) occurring in the fresh and brackish waters of the Shatt Al-Arab River and Estuary in southern Iraq, with the description of Ligophorus sagmarius sp. n. from the greenback mullet Chelon subviridis (Valenciennes).

Science.gov (United States)

Kritsky, Delane C; Khamees, Najim R; Ali, Atheer H

2013-12-01

The gills of three of five species of mullets (Teleostei: Mugiliformes: Mugilidae) collected from the brackish and fresh waters of southern Iraq were infected with species of Ligophorus (Monogenoidea: Dactylogyridae) as follows: greenback mullet Chelon subviridis (Valenciennes) infected with Ligophorus lebedevi Dmitrieva, Gerasev, Gibson, Pronkina and Galli, 2012, Ligophorus bantingensis Soo and Lim, 2012, Ligophorus sagmarius n. sp., and Ligophorus fluviatilis (Bychowsky, 1949) Dmitrieva, Gerasev, Gibson, Pronkina, and Galli, 2012; Klunzinger’s mullet Liza klunzingeri (Day) with L. bantingensis, L. fluviatilis, and an apparently undescribed species of Ligophorus; and abu mullet Liza abu (Heckel) with L. bantingensis and L. fluviatilis. The keeled mullet Liza carinata (Valenciennes) and Speigler’s mullet Valamugil speigleri (Bleeker) were uninfected. L. sagmarius n. sp. is described, and L. lebedevi and L. bantingensis are redescribed. Available specimens of L. fluviatilis and the undescribed species of Ligophorus from Klunzinger’s mullet were insufficient for description.

Radiocesium in brown trout (Salmo trutta) from a subalpine lake ecosystem after the Chernobyl reactor accident

International Nuclear Information System (INIS)

Brittain, J.E.; Storruste, Anders; Larsen, Elena

1991-01-01

After Chernobyl in April 1986, radioactive cesium has been measured in Oevre Heimdalsvatn, a Norwegian subalpine lake, situated in an area of high fallout. The lake is an important reference site and has been the subject of extensive ecosystem studies since the 1950s. Emphasis has been given to measuring long-term trends in the activity content of radioactive cesium in the brown trout (Salmo trutta) population. After ice-break in June 1986, the average total cesium activity content rose to 7000 Bq/kg wet weight. The activity content fell during 1987 and at ice-break in 1988 was 4000 Bq/kg. However, there was no further reduction during the summers of 1988 and 1989, possibly due to increased inputs from the catchment. There is considerable variation in the radiocesium activity content measured in individual fish. On the basis of the changes in cesium activity content in trout since 1986, an observed half-life for 137 Cs and 134 Cs in trout of 3.0 and 1.3 years, respectively, has been estimated. (author)

The Skin-Mucus Microbial Community of Farmed Atlantic Salmon (Salmo salar)

Science.gov (United States)

Minniti, Giusi; Hagen, Live Heldal; Porcellato, Davide; Jørgensen, Sven Martin; Pope, Phillip B.; Vaaje-Kolstad, Gustav

2017-01-01

The skin of the teleost is a flexible and scaled structure that protects the fish toward the external environment. The outermost surface of the skin is coated with mucus, which is believed to be colonized by a diverse bacterial community (commensal and/or opportunistic). Little is known about such communities and their role in fish welfare. In aquaculture, fish seem to be more susceptible to pathogens compared to wild fish. Indeed common fish farming practices may play important roles in promoting their vulnerability, possibly by causing changes to their microbiomes. In the present study, 16S rRNA gene amplicon sequencing was employed to analyze the composition of the farmed Salmo salar skin-mucus microbiome before and after netting and transfer. The composition of the bacterial community present in the rearing water was also investigated in order to evaluate its correlation with the community present on the fish skin. Our results reveal variability of the skin-mucus microbiome among the biological replicates before fish handling. On the contrary, after fish handling, the skin-mucus community exhibited structural similarity among the biological replicates and significant changes were observed in the bacterial composition compared to the fish analyzed prior to netting and transfer. Limited correlation was revealed between the skin-mucus microbiome and the bacterial community present in the rearing water. Finally, analysis of skin-mucus bacterial biomasses indicated low abundance for some samples, highlighting the need of caution when interpreting community data due to the possible contamination of water-residing bacteria. PMID:29104567

The Skin-Mucus Microbial Community of Farmed Atlantic Salmon (Salmo salar

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Giusi Minniti

2017-10-01

Full Text Available The skin of the teleost is a flexible and scaled structure that protects the fish toward the external environment. The outermost surface of the skin is coated with mucus, which is believed to be colonized by a diverse bacterial community (commensal and/or opportunistic. Little is known about such communities and their role in fish welfare. In aquaculture, fish seem to be more susceptible to pathogens compared to wild fish. Indeed common fish farming practices may play important roles in promoting their vulnerability, possibly by causing changes to their microbiomes. In the present study, 16S rRNA gene amplicon sequencing was employed to analyze the composition of the farmed Salmo salar skin-mucus microbiome before and after netting and transfer. The composition of the bacterial community present in the rearing water was also investigated in order to evaluate its correlation with the community present on the fish skin. Our results reveal variability of the skin-mucus microbiome among the biological replicates before fish handling. On the contrary, after fish handling, the skin-mucus community exhibited structural similarity among the biological replicates and significant changes were observed in the bacterial composition compared to the fish analyzed prior to netting and transfer. Limited correlation was revealed between the skin-mucus microbiome and the bacterial community present in the rearing water. Finally, analysis of skin-mucus bacterial biomasses indicated low abundance for some samples, highlighting the need of caution when interpreting community data due to the possible contamination of water-residing bacteria.

Photoperiod control of downstream movements of Atlantic salmon Salmo salar smolts

Science.gov (United States)

Zydlewski, Gayle B.; Stich, Daniel S.; McCormick, Stephen D.

2014-01-01

This study provides the first direct observations that photoperiod controls the initiation of downstream movement in Atlantic salmon Salmo salar smolts. Under simulated natural day length (LDN) conditions and seasonal increases in temperature, smolts increased their downstream movements five-fold for a period of 1 month in late spring. Under the same conditions, parr did not show changes in downstream movement behaviour. When given a shortened day length (10L:14D) beginning in late winter, smolts did not increase the number of downstream movements. An early increase in day length (16L:8D) in late winter resulted in earlier initiation and termination of downstream movements compared to the LDN group. Physiological status and behaviour were related but not completely coincident: gill Na+/K+-ATPase activity increased in all treatments and thyroid hormone was elevated prior to movement in 16L:8D treatment. The most parsimonious model describing downstream movement of smolts included synergistic effects of photoperiod treatment and temperature, indicating that peak movements occurred at colder temperatures in the 16L:8D treatment than in LDN, and temperature did not influence movement of smolts in the 10L:14D treatment. The complicated interactions of photoperiod and temperature are not surprising since many organisms have evolved to rely on correlations among environmental cues and windows of opportunity to time behaviours associated with life-history transitions. These complicated interactions, however, have serious implications for phenological adjustments and persistence ofS. salar populations in response to climate change.

Spatiotemporal dynamics of the Atlantic salmon (Salmo salar) Greenland fishery inferred from mixed-stock analysis

Science.gov (United States)

Gauthier-Ouellet, M.; Dionne, M.; Caron, F.; King, T.L.; Bernatchez, L.

2009-01-01

Mixed-stock fisheries refer to the exploitation of admixed fish stocks coming from different origins. We identified the North American origin of 2835 Atlantic salmon (Salmo salar) in the Greenland mixed-stock fishery during 11 years (1995-2006) at three localities using 13 microsatellites. The study included 52 baseline populations representing nine genetically distinct regional groups. The contribution of each group ranged from increasing contribution for Labrador (+14.9%) was observed during the time course of the study. The estimated regional contribution to the Greenland fishery was significantly correlated to the number of multi-sea-winter salmon regionally produced in 2002 (r = 0.79) and 2004 (r = 0.92). No difference in contribution was found between the three Greenland sampling localities. Ungava and Southern Qu??bec regions showed the highest mortality estimates caused by the fishery, ranging from 12.10% to 18.08%, for both years tested. No regional group was overrepresented in landings compared with their respective productivity. Yet, management precautions should still be taken as the fishery strongly selects large females, which could have evolutionary impacts on populations over the long term.

Trophic interference by Salmo trutta on Aplochiton zebra and Aplochiton taeniatus in southern Patagonian lakes.

Science.gov (United States)

Elgueta, A; González, J; Ruzzante, D E; Walde, S J; Habit, E

2013-02-01

The length and mass ratio, diet and isotopic composition of Aplochiton zebra and Aplochiton taeniatus inhabiting a Salmo trutta-invaded and a S. trutta-free lake in southern Patagonia were compared. Results indicate that S. trutta exercises important trophic interference over A. zebra and A. taeniatus, causing changes in their dietary composition by reducing the consumption of winged Diptera through changes in feeding behaviours that involve jumping out of the water. This effect is significantly higher in A. zebra than in A. taeniatus a species that has a highly specialized diet. The dietary changes of A. zebra and A. taeniatus in sympatry with S. trutta lead to an impoverishment of their isotopic nitrogen signals (δ(15)N), suggesting a reduction of their trophic position. In the case of A. zebra, this translates into a significant decrease in its body condition factor. Such interference could lead to a population decline of this species and would explain the current distribution range decline and allopatry with S. trutta in fluvial systems. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

HABITAT USE BY NATIVE AND STOCKED TROUT (SALMO TRUTTA L. IN TWO NORTHEAST STREAMS, PORTUGAL

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TEIXEIRA A.

2006-04-01

Full Text Available Habitat use by stocked and native brown trout (Salmo trutta L. was assessed in two headwater streams of North-eastern Portugal. Underwater observations were made during the summer season in three successive years to evaluate the effect of supplemental trout stocking. Multivariate analysis techniques applied to data sets on microhabitat use were exploited to identify the focal elevation (distance of fish from the bottom, total depth and cover as the variables that contribute most to the discrimination between stocked and native trout. Preference curves computed for native and stocked trout of the same age (1+, showed a distinct pattern in their ability to explore the available microhabitat resources. Stocked trout tended to occupy deeper pools (total depth > 100 cm vs. 60-100 cm for native trout, holding higher focal elevations (140-160 cm vs. 22.5 cm and cover (combination of boulders and overhanging vegetation or undercut banks. Furthermore, a high poststocking movement of 80% hatchery-reared fish was verified just one month after their release, suggesting that stocking did not contribute to the sustainable populations in either stream, and is far from being an adequate management technique.

Evidence for episodic acidification effects on migrating Atlantic salmon Salmo salar smolts

Science.gov (United States)

Kelly, John T; Lerner, Darrren T.; O'Dea, Michael F.; Regish, Amy M.; Monette, Michelle Y.; Hawkes, J.P.; Nislow, Keith H.; McCormick, Stephen

2015-01-01

Field studies were conducted to determine levels of gill aluminium as an index of acidification effects on migrating Atlantic salmon Salmo salar smolts in the north-eastern U.S.A. along mainstem river migration corridors in several major river basins. Smolts emigrating from the Connecticut River, where most (but not all) tributaries were well buffered, had low or undetectable levels of gill aluminium and high gill Na+/K+-ATPase (NKA) activity. In contrast, smolts emigrating from the upper Merrimack River basin where most tributaries are characterized by low pH and high inorganic aluminium had consistently elevated gill aluminium and lower gill NKA activity, which may explain the low adult return rates of S. salar stocked into the upper Merrimack catchment. In the Sheepscot, Narraguagus and Penobscot Rivers in Maine, river and year-specific effects on gill aluminium were detected that appeared to be driven by underlying geology and high spring discharge. The results indicate that episodic acidification is affecting S. salar smolts in poorly buffered streams in New England and may help explain variation in S. salar survival and abundance among rivers and among years, with implications for the conservation and recovery of S. salar in the north-eastern U.S.A. These results suggest that the physiological condition of outmigrating smolts may serve as a large-scale sentinel of landscape-level recovery of atmospheric pollution in this and other parts of the North Atlantic region.

Structural and functional studies of STAT1 from Atlantic salmon (Salmo salar

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Thim Hanna L

2010-03-01

Full Text Available Abstract Background Type I and type II interferons (IFNs exert their effects mainly through the JAK/STAT pathway, which is presently best described in mammals. STAT1 is involved in signaling pathways induced by both types of IFNs. It has a domain-like structure including an amino-terminus that stabilizes interaction between STAT dimers in a promoter-binding situation, a coiled coil domain facilitating interactions to other proteins, a central DNA-binding domain, a SH2 domain responsible for dimerization of phosphorylated STATs and conserved phosphorylation sites within the carboxy terminus. The latter is also the transcriptional activation domain. Results A salmon (Salmo salar STAT1 homologue, named ssSTAT1a, has been identified and was shown to be ubiquitously expressed in various cells and tissues. The ssSTAT1a had a domain-like structure with functional motifs that are similar to higher vertebrates. Endogenous STAT1 was shown to be phosphorylated at tyrosine residues both in salmon leukocytes and in TO cells treated with recombinant type I and type II IFNs. Also ectopically expressed ssSTAT1 was phosphorylated in salmon cells upon in vitro stimulation by the IFNs, confirming that the cloned gene was recognized by upstream tyrosine kinases. Treatment with IFNs led to nuclear translocation of STAT1 within one hour. The ability of salmon STAT1 to dimerize was also shown. Conclusions The structural and functional properties of salmon STAT1 resemble the properties of mammalian STAT1.

Lipid peroxidation analysis in salmon (Salmo salar L.) processed by e-beam

International Nuclear Information System (INIS)

Thomaz, Fernanda S.; Trindade, Reginaldo A.; Fanaro, Gustavo B.; Araujo, Michel M.; Villavicencio, Ana Lucia C.H.; Mancini-Filho, Jorge

2007-01-01

In Brazil the consumption of fish is relatively small when compared with other source of meat protein. However the diets rich in fish have association with a wide range of positive health effects, due your great deal the fat acids omega 3, EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Salmon (Salmo salar L.) specifically have those fat acids in main quantity. The omega 3 fat acids are related to the prevention of several not transmissible illness; with emphasis to cardiovascular, hypertriglyceridemia, cancer, osteoporosis and inflammatory and anti immune diseases. Food borne illnesses have been a growing concern to the governments, producers and consumers, mainly regarding the damages they cause to human health. In this context, irradiation is used as a method to preserve food. The present work aim to evaluate the lipid peroxidation in natura salmon filet irradiated on the basis of thiobarbituric acid reactive substances (TBARS). Samples were irradiated in an e beam accelerator (Radiation Dynamics Co. model JOB, New York, USA), 1,5 MeV-25mA at doses of 0, 1.0 and 2.0 kGy, analyzed 7, 15, 21, 30 e 45 days after irradiation. Irradiated samples analyzed during a 45 day period, showed a higher lipid peroxidation than the control samples at the same period, increasing with dose and storage time. However, it did not pass the permitted value. Irradiation demonstrated effective without compromising the quality of the food. (author)

Lipid peroxidation analysis in salmon (Salmo salar L.) processed by e-beam

Energy Technology Data Exchange (ETDEWEB)

Thomaz, Fernanda S.; Trindade, Reginaldo A.; Fanaro, Gustavo B.; Araujo, Michel M.; Villavicencio, Ana Lucia C.H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: villavic@ipen.br; Mancini-Filho, Jorge [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas]. E-mail: jmancini@usp.br

2007-07-01

In Brazil the consumption of fish is relatively small when compared with other source of meat protein. However the diets rich in fish have association with a wide range of positive health effects, due your great deal the fat acids omega 3, EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Salmon (Salmo salar L.) specifically have those fat acids in main quantity. The omega 3 fat acids are related to the prevention of several not transmissible illness; with emphasis to cardiovascular, hypertriglyceridemia, cancer, osteoporosis and inflammatory and anti immune diseases. Food borne illnesses have been a growing concern to the governments, producers and consumers, mainly regarding the damages they cause to human health. In this context, irradiation is used as a method to preserve food. The present work aim to evaluate the lipid peroxidation in natura salmon filet irradiated on the basis of thiobarbituric acid reactive substances (TBARS). Samples were irradiated in an e beam accelerator (Radiation Dynamics Co. model JOB, New York, USA), 1,5 MeV-25mA at doses of 0, 1.0 and 2.0 kGy, analyzed 7, 15, 21, 30 e 45 days after irradiation. Irradiated samples analyzed during a 45 day period, showed a higher lipid peroxidation than the control samples at the same period, increasing with dose and storage time. However, it did not pass the permitted value. Irradiation demonstrated effective without compromising the quality of the food. (author)

Differential metabolite levels in response to spawning-induced inappetence in Atlantic salmon Salmo salar.

Science.gov (United States)

Cipriano, Rocco C; Smith, McKenzie L; Vermeersch, Kathleen A; Dove, Alistair D M; Styczynski, Mark P

2015-03-01

Atlantic salmon Salmo salar undergo months-long inappetence during spawning, but it is not known whether this inappetence is a pathological state or one for which the fish are adapted. Recent work has shown that inappetent whale sharks can exhibit circulating metabolite profiles similar to ketosis known to occur in humans during starvation. In this work, metabolite profiling was used to explore differences in analyte profiles between a cohort of inappetent spawning run Atlantic salmon and captively reared animals that were fed up to and through the time of sampling. The two classes of animals were easily distinguished by their metabolite profiles. The sea-run fish had elevated ɷ-9 fatty acids relative to the domestic feeding animals, while other fatty acid concentrations were reduced. Sugar alcohols were generally elevated in inappetent animals, suggesting potentially novel metabolic responses or pathways in fish that feature these compounds. Compounds expected to indicate a pathological catabolic state were not more abundant in the sea-run fish, suggesting that the animals, while inappetent, were not stressed in an unnatural way. These findings demonstrate the power of discovery-based metabolomics for exploring biochemistry in poorly understood animal models. Copyright © 2015 Elsevier Inc. All rights reserved.

Differential metabolic profiles associated to movement behaviour of stream-resident brown trout (Salmo trutta.

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Neus Oromi

Full Text Available The mechanisms that can contribute in the fish movement strategies and the associated behaviour can be complex and related to the physiology, genetic and ecology of each species. In the case of the brown trout (Salmo trutta, in recent research works, individual differences in mobility have been observed in a population living in a high mountain river reach (Pyrenees, NE Spain. The population is mostly sedentary but a small percentage of individuals exhibit a mobile behavior, mainly upstream movements. Metabolomics can reflect changes in the physiological process and can determine different profiles depending on behaviour. Here, a non-targeted metabolomics approach was used to find possible changes in the blood metabolomic profile of S. trutta related to its movement behaviour, using a minimally invasive sampling. Results showed a differentiation in the metabolomic profiles of the trouts and different level concentrations of some metabolites (e.g. cortisol according to the home range classification (pattern of movements: sedentary or mobile. The change in metabolomic profiles can generally occur during the upstream movement and probably reflects the changes in metabolite profile from the non-mobile season to mobile season. This study reveals the contribution of the metabolomic analyses to better understand the behaviour of organisms.

Differential metabolic profiles associated to movement behaviour of stream-resident brown trout (Salmo trutta).

Science.gov (United States)

Oromi, Neus; Jové, Mariona; Pascual-Pons, Mariona; Royo, Jose Luis; Rocaspana, Rafel; Aparicio, Enric; Pamplona, Reinald; Palau, Antoni; Sanuy, Delfi; Fibla, Joan; Portero-Otin, Manuel

2017-01-01

The mechanisms that can contribute in the fish movement strategies and the associated behaviour can be complex and related to the physiology, genetic and ecology of each species. In the case of the brown trout (Salmo trutta), in recent research works, individual differences in mobility have been observed in a population living in a high mountain river reach (Pyrenees, NE Spain). The population is mostly sedentary but a small percentage of individuals exhibit a mobile behavior, mainly upstream movements. Metabolomics can reflect changes in the physiological process and can determine different profiles depending on behaviour. Here, a non-targeted metabolomics approach was used to find possible changes in the blood metabolomic profile of S. trutta related to its movement behaviour, using a minimally invasive sampling. Results showed a differentiation in the metabolomic profiles of the trouts and different level concentrations of some metabolites (e.g. cortisol) according to the home range classification (pattern of movements: sedentary or mobile). The change in metabolomic profiles can generally occur during the upstream movement and probably reflects the changes in metabolite profile from the non-mobile season to mobile season. This study reveals the contribution of the metabolomic analyses to better understand the behaviour of organisms.

Daytime habitat selection for juvenile parr brown trout (Salmo trutta in small lowland streams

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Conallin J.

2014-03-01

Full Text Available Physical habitat is important in determining the carrying capacity of juvenile brown trout, and within freshwater management. Summer daytime physical habitat selection for the parr lifestage (7–20 cm juvenile brown trout (Salmo trutta was assessed in 6 small lowland streams. Habitat preference was determined for the four variables; water velocity, water depth, substrate and cover, and the preferences for physical habitat selection were expressed in terms of habitat suitability indices (HSI’s. The statistical confidence of HSI’s was evaluated using power analysis. It was found that a minimum of 22 fish observations was needed to have statistical confidence in the HSIs for water depth, and a minimum of 92 fish observations for water velocity during daytime summer conditions. Generally parr were utilising the deeper habitats, indicating preference for deeper water. Cover was also being selected for at all sites, but selection was inconsistent among sites for the variables substrate and velocity. The results indicate that during daytime summer conditions water depth is a significant variable for parr habitat selection in these small lowland streams, with cover also being important. Therefore, daytime refugia may be a critical limiting factor for parr in small lowland streams, and important for stream management actions under the Water Framework Directive.

Disposition of naphthalene and its metabolites in the brain of rainbow trout (Salmo gairdneri)

International Nuclear Information System (INIS)

Collier, T.K.; Krahn, M.M.; Malins, D.C.

1980-01-01

Rainbow trout (Salmo gairdneri) were exposed to orally administered [ 3 H]naphthalene. Another group received naphthyl glucuronic acid and naphthyl sulfate via iv injection. Brain, liver, and blood were assayed for the parent compound and/or total metabolites. Individual naphthalene derivatives were determined by high-performance liquid chromatography (hplc) using either radiometric or on-line fluorimetric detection systems. Naphthalene concentrations in brain (8.2 pmol/mg dry wt at 16 hr after feeding) approximated those found at the same time in liver (7.4 pmol/mg dry wt). A nonconjugated naphthalene derivative, 1,2-dihydro-1,2-dihydroxynaphthalene, also accumulated in brain (0.041 pmol/mg dry wt after 16 hr), although to a lesser degree than in liver (0.10 pmol/mg dry wt after 16 hr). Conjugated naphthalene derivatives, 1-naphthyl sulfate and 1-naphthyl glucuronic acid, although present in liver and blood, were largely excluded from the brain. Low naphthalene hydroxylase activity (<2.0 pmol product formed/mg protein/min) indicated that the trout brain has a minimal ability to oxidize aromatic hydrocarbons. These findings suggest that the brain of adult trout is substantially different from other tissues (e.g., liver and blood) with respect to the disposition of naphthalene and its metabolites

Study of the quality characteristics in cold-smoked salmon (Salmo salar) originating from pre- or post-rigor raw material.

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Birkeland, S; Akse, L

2010-01-01

Improved slaughtering procedures in the salmon industry have caused a delayed onset of rigor mortis and, thus, a potential for pre-rigor secondary processing. The aim of this study was to investigate the effect of rigor status at time of processing on quality traits color, texture, sensory, microbiological, in injection salted, and cold-smoked Atlantic salmon (Salmo salar). Injection of pre-rigor fillets caused a significant (Prigor processed fillets; however, post-rigor (1477 ± 38 g) fillets had a significant (P>0.05) higher fracturability than pre-rigor fillets (1369 ± 71 g). Pre-rigor fillets were significantly (Prigor fillets (37.8 ± 0.8) and had significantly lower (Prigor processed fillets. This study showed that similar quality characteristics can be obtained in cold-smoked products processed either pre- or post-rigor when using suitable injection salting protocols and smoking techniques. © 2010 Institute of Food Technologists®

Density-dependent effects of non-native brown trout Salmo trutta on the species-area relationship in stream fish assemblages.

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Hasegawa, K; Mori, T; Yamazaki, C

2017-01-01

The spatial scale and density-dependent effects of non-native brown trout Salmo trutta on species richness of fish assemblages were examined at 48 study sites in Mamachi Stream, a tributary of Chitose River, Hokkaido, Japan. The density of age ≥1 year S. trutta was high in the upstream side of the main stem of Mamachi Stream. Fish species richness increased with increasing area of study sites (habitat size), but the increasing magnitude of the species richness with area decreased with increasing age of ≥1 year S. trutta density. The relationships between age ≥1 year S. trutta, however, and presence-absence of each species seemed to be different among species. Species richness was also determined by location and physical environmental variables, i.e. it was high on the downstream side and in structurally complex environments. © 2016 The Fisheries Society of the British Isles.

Survival of migrating sea trout (Salmo trutta ) smolts during their passage of an artificial lake in a Danish lowland stream

DEFF Research Database (Denmark)

Schwinn, Michael; Aarestrup, Kim; Baktoft, Henrik

2017-01-01

Artificial lake development is often used as a management tool to reduce nutrient runoff to coastal waters. Denmark has restored more than 10 000 ha of wetlands and lakes in the last 14 years as a consequence of ‘Action Plans for the Aquatic Environment’, which aim to meet the demands...... of the European Union’s Water Framework Directive. Juvenile, seaward migrating salmonids are highly affected by impounded waterbodies, as they are subjected to extraordinary high mortalities due to predation and altered habitat. From 2005 to 2015, survival and migration patterns of wild brown trout (Salmo trutta....... Water temperature and discharge were key environmental factors affecting survival of the smolts during the passage of the lake. Furthermore, smolt survival was negatively correlated with condition factor. This elevated level of smolt mortality may seriously compromise self-sustaining anadromous salmonid...

Non-invasive ancient DNA protocol for fluid-preserved specimens and phylogenetic systematics of the genus Orestias (Teleostei: Cyprinodontidae).

Science.gov (United States)

Garrigos, Yareli Esquer; Hugueny, Bernard; Koerner, Kellie; Ibañez, Carla; Bonillo, Celine; Pruvost, Patrice; Causse, Romain; Cruaud, Corinne; Gaubert, Philippe

2013-01-01

Specimens stored in museum collections represent a crucial source of morphological and genetic information, notably for taxonomically problematic groups and extinct taxa. Although fluid-preserved specimens of groups such as teleosts may constitute an almost infinite source of DNA, few ancient DNA protocols have been applied to such material. In this study, we describe a non-invasive Guanidine-based (GuSCN) ancient DNA extraction protocol adapted to fluid-preserved specimens that we use to re-assess the systematics of the genus Orestias (Cyprinodontidae: Teleostei). The latter regroups pupfishes endemic to the inter-Andean basin that have been considered as a 'species flock', and for which the morphology-based taxonomic delimitations have been hotly debated. We extracted DNA from the type specimens of Orestias kept at the Muséum National d'Histoire Naturelle of Paris, France, including the extinct species O. cuvieri. We then built the first molecular (control region [CR] and rhodopsin [RH]) phylogeny including historical and recently collected representatives of all the Orestias complexes as recognized by Parenti (1984a): agassizii, cuvieri, gilsoni and mulleri. Our ancient DNA extraction protocol was validated after PCR amplification through an approach based on fragment-by-fragment chimera detection. After optimization, we were able to amplify Titicaca. We could not recover the reciprocal monophyly of any of the 15 species or morphotypes that were considered in our analyses, possibly due to incomplete lineage sorting and/or hybridization events. As a consequence, our results starkly question the delineation of a series of diagnostic characters listed in the literature for Orestias. Although not included in our phylogenetic analysis, the syntype of O. jussiei could not be assigned to the agassizii complex as newly defined. The CR sequence of the extinct O. cuvieri was recovered within the cuvieri clade (same haplotype as one representative of O. pentlandii), so

The diet of otters ( Lutra lutra L.) in Danish freshwater habitats : comparisons of prey fish populations

DEFF Research Database (Denmark)

Taastrom, H.M.; Jacobsen, Lene

1999-01-01

Otter spraints from five Danish freshwater localities were analysed. In all localities fish was the main prey (76-99% of estimated bulk), especially in winter. Depending on locality, the prey fish mainly consisted of cyprinids (Cyprinidae), percids (Percidae) or salmonids (Salmonidae). Seasonal v...

Evaluation of feed and feeding regime on growth performance, flesh quality and fecal viscosity of Atlantic salmon ( Salmo salar L.) in recirculating aquaculture systems

Science.gov (United States)

Sun, Guoxiang; Liu, Ying; Li, Yong; Li, Xian; Wang, Shunkui

2015-10-01

The effects of different feeds and feeding regimes on growth performance, flesh quality and fecal viscosity of Atlantic salmon ( Salmo salar L.) in recirculating aquaculture systems (RAS) were investigated. Fish (initial body weight of 1677 g ± 157 g) were fed with four commercial feeds (Nosan salmon-NS, Aller gold-AG, Skretting salmon-SS and Han ye-HY) in two feeding regimes (80% and 100% satiation) for 78 d. The results showed that salmon specific growth ratio (SGR) and weight gain ratio (WGR) were significantly affected by feed type and feeding regime ( P vitamin E, hydroxyproline (HYP), liquid loss and muscle pH among all groups showed significant differences ( P important quality attributes of Atlantic salmon.

Investigation of humic acid effects versus cadmium toxicity on hematological paramaters of Brown Trout (Salmo trutta fario.

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E.Mahmut Kocaman

2015-12-01

Full Text Available Bu çalışmada, kahverengi alabalıklarda (Salmo trutta fario Linneaus, 1792 kadmiyum toksisitesine karşı humik asitin koruyucu etkisi bazı hematolojik parametreler açısından araştırılmıştır. Balıklar kadmiyum ve/veya humik asite (2ppm Cd, 2ppm Cd+ 5 ppm humik asit ve kontrol 7 gün boyunca maruz bırakılmışlardır. Deneme periyodu sonunda hematolojik parametrelerden hemoglobin, hematokrit, eritrosit, eritrosit başına düşen ortalama hemoglobin miktarı (MCH, ortalama eritrosit hacmi (MCV ve eritrosit başına düşen ortalama hemoglobin konsantrasyonu (MCHC değerlerinde meydana gelen değişimler incelenmiştir. İstatistiki açıdan tüm parametrelerde gruplar arası fark belirlenmiş olsa da kırmızı kan hücresi (RBC, hematokrit, trombosit sayısı, MCV ve MCH parametreleri p

Short- and long-term effects of dietary l-tryptophan supplementation on the neuroendocrine stress response in seawater-reared Atlantic salmon (Salmo salar)

DEFF Research Database (Denmark)

Basic, D.; Krogdahl, T.; Scholden, J.

2013-01-01

. Basal plasma cortisol levels were lower among non-stressed fish at 1 and 10. days post dietary Trp supplementation. By comparison, stressed fish displayed stimulatory post-stress plasma cortisol responses at 1 and 2. days after the Trp regimen was terminated. However, a reversed pattern was observed...... as well as habituation to seawater involves the neuroendocrine stress response, suggesting that such environmental factors may modulate the stress-reducing effects of Trp. To date, studies that have investigated the neuroendocrine effects of dietary Trp have only been conducted in rainbow trout...... (. Oncorhynchus mykiss), a salmonid species, under conditions featuring social isolation in the freshwater environment. Here, we address the effects of dietary Trp on post-stress plasma cortisol and hypothalamic monoamines in seawater-adapted Atlantic salmon (. Salmo salar), reared at densities relevant...

Sex hormone concentrations and gonad histology in brown trout (Salmo Trutta) exposed to 17β-estradiol and bisphenol A

DEFF Research Database (Denmark)

B Bjerregaard, Lisette; Lindholst, Christian; Korsgaard, Bodil

2008-01-01

Abstract: The impact of 17 beta-estradiol (E2) and bisphenol A (BPA) on steroid hormone levels and gonad development in brown trout (Salmo trutta) was determined. Exposure took place from 0 to 63 days post-fertilisation (dpf) and gonad development was followed till 400 dpf. The onset...... began during the first weeks of embryonic development. Few consistent effects were found on the sex differentiation of the brown trout. Only one intersex fish (4.5%) was found among male fish at 400 dpf exposed to 500 ng E2/l. Females with male germ cells among the normally developing oocytes were...... observed in all groups (in up to 50% of the female fish, independently of exposure regime). The fact that exposure to 500 ng E2/l only caused subtle effects in a small number of individuals indicates that exposure during early life stages results in little to no induction of endocrine disruption in brown...

Thermal and oxidative stability of Atlantic salmon oil (Salmo salar L. and complexation with β-cyclodextrin

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Daniel I. Hădărugă

2016-02-01

Full Text Available The thermal and oxidative stability of Atlantic salmon oil (Salmo salar L. as well as its β-cyclodextrin (β-CD complexation ability has been verified for the first time. The main omega-3 fatty acids, EPA and DHA, were significantly degraded, even at 50 °C. Their relative concentrations decrease from 6.1% for EPA and 4.1% for DHA to 1.7% and 1.5% after degradation at 150 °C, respectively. On the other hand, the relative concentrations of monounsaturated and saturated fatty acids remained constant or slightly increased by a few percent after degradation (e.g., from 10.7% to 12.9% for palmitic acid. Co-crystallization of ASO with β-CD at a host–guest ratio of 1:1 and 3:1 from an ethanol–water mixture and kneading methods has been used for the preparation of β-CD/ASO complexes. The analysis of the complexes by thermogravimetry, differential scanning calorimetry (DSC, and Karl Fischer titration (KFT as well as the decrease of the “strongly-retained” water content confirm the formation of the inclusion compound. Furthermore, the DSC parameters correlate well with the KFT kinetic data for β-CD/ASO complexes.

Intestinal microbiota of healthy and unhealthy Atlantic salmon Salmo salar L. in a recirculating aquaculture system

Science.gov (United States)

Wang, Chun; Sun, Guoxiang; Li, Shuangshuang; Li, Xian; Liu, Ying

2018-03-01

The present study sampled the intestinal content of healthy and unhealthy Atlantic salmon ( Salmo salar L.), the ambient water of unhealthy fish, and the biofilter material in the recirculating aquaculture system (RAS) to understand differences in the intestinal microbiota. The V4-V5 regions of the prokaryotic 16S rRNA genes in the samples were analyzed by MiSeq high-throughput sequencing. The fish were adults with no differences in body length or weight. Representative members of the intestinal microbiota were identified. The intestinal microbiota of the healthy fish included Proteobacteria (44.33%), Actinobacteria (17.89%), Bacteroidetes (15.25%), and Firmicutes (9.11%), among which the families Micrococcaceae and Oxalobacteraceae and genera Sphingomonas, Streptomyces, Pedobacter, Janthinobacterium, Burkholderia, and Balneimonas were most abundant. Proteobacteria (70.46%), Bacteroidetes (7.59%), and Firmicutes (7.55%) dominated the microbiota of unhealthy fish, and Chloroflexi (2.71%), and Aliivibrio and Vibrio as well as genera in the family Aeromonadaceae were most strongly represented. Overall, the intestinal hindgut microbiota differed between healthy and unhealthy fish. This study offers a useful tool for monitoring the health status of fish and for screening the utility of probiotics by studying the intestinal microbiota.

Morphological and molecular confirmation of Myxobolus cerebralis myxospores infecting wild‑caught and cultured trout in North Carolina (SE USA).

Science.gov (United States)

Ruiz, Carlos F; Rash, Jacob M; Arias, Cova R; Besler, Doug A; Orélis-Ribeiro, Raphael; Womble, Matthew R; Roberts, Jackson R; Warren, Micah B; Ray, Candis L; Lafrentz, Stacey; Bullard, Stephen A

2017-11-21

We used microscopy and molecular biology to provide the first documentation of infections of Myxobolus cerebralis (Myxozoa: Myxobolidae), the etiological agent of whirling disease, in trout (Salmonidae) from North Carolina (USA) river basins. A total of 1085 rainbow trout Oncorhynchus mykiss, 696 brown trout Salmo trutta, and 319 brook trout Salvelinus fontinalis from 43 localities across 9 river basins were screened. Myxospores were observed microscopically in pepsin-trypsin digested heads of rainbow and brown trout from the Watauga River Basin. Those infections were confirmed using the prescribed nested polymerase chain reaction (PCR; 18S rDNA), which also detected infections in rainbow, brown, and brook trout from the French Broad River Basin and the Yadkin Pee-Dee River Basin. Myxospores were 9.0-10.0 µm (mean ± SD = 9.6 ± 0.4; N = 119) long, 8.0-10.0 µm (8.8 ± 0.6; 104) wide, and 6.0-7.5 µm (6.9 ± 0.5; 15) thick and had polar capsules 4.0-6.0 µm (5.0 ± 0.5; 104) long, 2.5-3.5 µm (3.1 ± 0.3; 104) wide, and with 5 or 6 polar filament coils. Myxospores from these hosts and rivers were morphologically indistinguishable and molecularly identical, indicating conspecificity, and the resulting 18S rDNA and ITS-1 sequences derived from these myxospores were 99.5-100% and 99.3-99.8% similar, respectively, to published GenBank sequences ascribed to M. cerebralis. This report comprises the first taxonomic circumscription and molecular confirmation of M. cerebralis in the southeastern USA south of Virginia.

Salmonid Chromosome Evolution as Revealed by a Novel Method for Comparing RADseq Linkage Maps

Science.gov (United States)

Gosselin, Thierry; Normandeau, Eric; Lamothe, Manuel; Isabel, Nathalie; Audet, Céline; Bernatchez, Louis

2016-01-01

Whole genome duplication (WGD) can provide material for evolutionary innovation. Family Salmonidae is ideal for studying the effects of WGD as the ancestral salmonid underwent WGD relatively recently, ∼65 Ma, then rediploidized and diversified. Extensive synteny between homologous chromosome arms occurs in extant salmonids, but each species has both conserved and unique chromosome arm fusions and fissions. Assembly of large, outbred eukaryotic genomes can be difficult, but structural rearrangements within such taxa can be investigated using linkage maps. RAD sequencing provides unprecedented ability to generate high-density linkage maps for nonmodel species, but can result in low numbers of homologous markers between species due to phylogenetic distance or differences in library preparation. Here, we generate a high-density linkage map (3,826 markers) for the Salvelinus genera (Brook Charr S. fontinalis), and then identify corresponding chromosome arms among the other available salmonid high-density linkage maps, including six species of Oncorhynchus, and one species for each of Salmo, Coregonus, and the nonduplicated sister group for the salmonids, Northern Pike Esox lucius for identifying post-duplicated homeologs. To facilitate this process, we developed MapComp to identify identical and proximate (i.e. nearby) markers between linkage maps using a reference genome of a related species as an intermediate, increasing the number of comparable markers between linkage maps by 5-fold. This enabled a characterization of the most likely history of retained chromosomal rearrangements post-WGD, and several conserved chromosomal inversions. Analyses of RADseq-based linkage maps from other taxa will also benefit from MapComp, available at: https://github.com/enormandeau/mapcomp/ PMID:28173098

The physiological basis of the migration continuum in brown trout (Salmo trutta).

Science.gov (United States)

Boel, Mikkel; Aarestrup, Kim; Baktoft, Henrik; Larsen, Torben; Søndergaard Madsen, Steffen; Malte, Hans; Skov, Christian; Svendsen, Jon C; Koed, Anders

2014-01-01

Partial migration is common in many animal taxa; however, the physiological variation underpinning migration strategies remains poorly understood. Among salmonid fishes, brown trout (Salmo trutta) is one of the species that exhibits the most complex variation in sympatric migration strategies, expressed as a migration continuum, ranging from residency to anadromy. In looking at brown trout, our objective with this study was to test the hypothesis that variation in migration strategies is underpinned by physiological variation. Prior to migration, physiological samples were taken from fish in the stream and then released at the capture site. Using telemetry, we subsequently classified fish as resident, short-distance migrants (potamodromous), or long-distance migrants (potentially anadromous). Our results revealed that fish belonging to the resident strategy differed from those exhibiting any of the two migratory strategies. Gill Na,K-ATPase activity, condition factor, and indicators of nutritional status suggested that trout from the two migratory strategies were smoltified and energetically depleted before leaving the stream, compared to those in the resident strategy. The trout belonging to the two migratory strategies were generally similar; however, lower triacylglycerides levels in the short-distance migrants indicated that they were more lipid depleted prior to migration compared with the long-distance migrants. In the context of migration cost, we suggest that additional lipid depletion makes migrants more inclined to terminate migration at the first given feeding opportunity, whereas individuals that are less lipid depleted will migrate farther. Collectively, our data suggest that the energetic state of individual fish provides a possible mechanism underpinning the migration continuum in brown trout.

Sulphated glycosaminoglycans and proteoglycans in the developing vertebral column of juvenile Atlantic salmon (Salmo salar).

Science.gov (United States)

Hannesson, Kirsten O; Ytteborg, Elisabeth; Takle, Harald; Enersen, Grethe; Bæverfjord, Grete; Pedersen, Mona E

2015-08-01

In the present study, the distribution of sulphated glycosaminoglycans (GAGs) in the developing vertebral column of Atlantic salmon (Salmo salar) at 700, 900, 1100 and 1400 d° was examined by light microscopy. The mineralization pattern was outlined by Alizarin red S and soft structures by Alcian blue. The temporal and spatial distribution patterns of different types of GAGs: chondroitin-4-sulphate/dermatan sulphate, chondroitin-6-sulphate, chondroitin-0-sulphate and keratan sulphate were addressed by immunohistochemistry using monoclonal antibodies against the different GAGs. The specific pattern obtained with the different antibodies suggests a unique role of the different GAG types in pattern formation and mineralization. In addition, the distribution of the different GAG types in normal and malformed vertebral columns from 15 g salmon was compared. A changed expression pattern of GAGs was found in the malformed vertebrae, indicating the involvement of these molecules during the pathogenesis. The molecular size of proteoglycans (PGs) in the vertebrae carrying GAGs was analysed with western blotting, and mRNA transcription of the PGs aggrecan, decorin, biglycan, fibromodulin and lumican by real-time qPCR. Our study reveals the importance of GAGs in development of vertebral column also in Atlantic salmon and indicates that a more comprehensive approach is necessary to completely understand the processes involved.

Global transcriptional analysis of short-term hepatic stress responses in Atlantic salmon (Salmo salar) exposed to depleted uranium

Science.gov (United States)

Song, You; Salbu, Brit; Teien, Hans-Christian; Heier, Lene Sørlie; Rosseland, Bjørn Olav; Høgåsen, Tore; Tollefsen, Knut Erik

2014-01-01

Potential environmental hazards of radionuclides are often studied at the individual level. Sufficient toxicogenomics data at the molecular/cellular level for understanding the effects and modes of toxic action (MoAs) of radionuclide is still lacking. The current article introduces transcriptomic data generated from a recent ecotoxicological study, with the aims to characterize the MoAs of a metallic radionuclide, deplete uranium (DU) in an ecologically and commercially important fish species, Atlantic salmon (Salmo salar). Salmon were exposed to three concentrations (0.25, 0.5 and 1.0 mg/L) of DU for 48 h. Short-term global transcriptional responses were studied using Agilent custom-designed high density 60,000-feature (60 k) salmonid oligonucleotide microarrays (oligoarray). The microarray datasets deposited at Gene Expression Omnibus (GEO ID: GSE58824) were associated with a recently published study by Song et al. (2014) in BMC Genomics. The authors describe the experimental data herein to build a platform for better understanding the toxic mechanisms and ecological hazard of radionuclides such as DU in fish. PMID:26484125

Global transcriptional analysis of short-term hepatic stress responses in Atlantic salmon (Salmo salar exposed to depleted uranium

Directory of Open Access Journals (Sweden)

You Song

2014-12-01

Full Text Available Potential environmental hazards of radionuclides are often studied at the individual level. Sufficient toxicogenomics data at the molecular/cellular level for understanding the effects and modes of toxic action (MoAs of radionuclide is still lacking. The current article introduces transcriptomic data generated from a recent ecotoxicological study, with the aims to characterize the MoAs of a metallic radionuclide, deplete uranium (DU in an ecologically and commercially important fish species, Atlantic salmon (Salmo salar. Salmon were exposed to three concentrations (0.25, 0.5 and 1.0 mg/L of DU for 48 h. Short-term global transcriptional responses were studied using Agilent custom-designed high density 60,000-feature (60 k salmonid oligonucleotide microarrays (oligoarray. The microarray datasets deposited at Gene Expression Omnibus (GEO ID: GSE58824 were associated with a recently published study by Song et al. (2014 in BMC Genomics. The authors describe the experimental data herein to build a platform for better understanding the toxic mechanisms and ecological hazard of radionuclides such as DU in fish.

Extended spawning in brown trout (Salmo trutta populations from the Southern Iberian Peninsula: the role of climate variability

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José E. Larios-López

2014-02-01

Full Text Available The reproductive periods of brown trout (Salmo trutta populations in 12 rivers in the Baetic Mountains in southern Spain were studied from 2008 to 2013. This area is an ecological and geographical limit for the distribution of this species in Europe. We found that the spawning period has been markedly extended in these fish. The mean spawning dates in the studied populations are consistent with the European trend at this latitude, but our data suggest that females from most of the populations that we studied are able to produce eggs from early October through late April or early May, yielding a reproductive period of between 150 and 170 days, the longest and most delayed brown trout reproduction periods that have been reported in the literature. We believe that such expanded spawning periods result primarily from the unpredictability of the Mediterranean climate, although it is possible that other factors may have contributed to the development of this reproductive behaviour. This hypothesis is discussed in the context of a comparison of our results with those found for other European S. trutta populations.

Ascent ability of brown trout, Salmo trutta, and two Iberian cyprinids − Iberian barbel, Luciobarbus bocagei, and northern straight-mouth nase, Pseudochondrostoma duriense − in a vertical slot fishway

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Sanz-Ronda, Fco. Javier; Bravo-Cordoba, F.J.; Fuentes-Perez, J.F.; Castro-Santos, Theodore R.

2016-01-01

Passage performance of brown trout (Salmo trutta), Iberian barbel (Luciobarbus bocagei), and northern straight-mouth nase (Pseudochondrostoma duriense) was investigated in a vertical slot fishway in the Porma River (Duero River basin, Spain) using PIT telemetry. We analysed the effects of different fishway discharges on motivation and passage success. Both cyprinid species ascended the fishway easily, performing better than the trout despite their theoretically weaker swimming performance. Fishway discharge affected fish motivation although it did not clearly influence passage success. Observed results can guide design and operation criteria of vertical slot fishways for native Iberian fish.

Survival of Atlantic salmon Salmo salar smolts through a hydropower complex.

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Stich, D S; Bailey, M M; Zydlewski, J D

2014-10-01

This study evaluated Atlantic salmon Salmo salar smolt survival through the lower Penobscot River, Maine, U.S.A., and characterized relative differences in proportional use and survival through the main-stem of the river and an alternative migration route, the Stillwater Branch. The work was conducted prior to removal of two main-stem dams and operational changes in hydropower facilities in the Stillwater Branch. Survival and proportional use of migration routes in the lower Penobscot were estimated from multistate (MS) models based on 6 years of acoustic telemetry data from 1669 smolts and 2 years of radio-telemetry data from 190 fish. A small proportion (0·12, 95% c.i. = 0·06-0·25) of smolts used the Stillwater Branch, and mean survival through the two operational dams in this part of the river was relatively high (1·00 and 0·97). Survival at Milford Dam, the dam that will remain in the main-stem of the Penobscot River, was relatively low (0·91), whereas survival through two dams that were removed was relatively high (0·99 and 0·98). Smolt survival could decrease in the Stillwater Branch with the addition of two new powerhouses while continuing to meet fish passage standards. The effects of removing two dams in the main-stem are expected to be negligible for smolt survival based on high survival observed from 2005 to 2012 at those locations. Survival through Milford Dam was been well below current regulatory standards, and thus improvement of passage at this location offers the best opportunity for improving overall smolt survival in the lower river. © 2014 The Fisheries Society of the British Isles.

Extraction of gelatin from salmon (Salmo salar) fish skin using trypsin-aided process: optimization by Plackett-Burman and response surface methodological approaches.

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Fan, HuiYin; Dumont, Marie-Josée; Simpson, Benjamin K

2017-11-01

Gelatin from salmon ( Salmo salar ) skin with high molecular weight protein chains ( α -chains) was extracted using trypsin-aided process. Response surface methodology was used to optimise the extraction parameters. Yield, hydroxyproline content and protein electrophoretic profile via sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of gelatin were used as responses in the optimization study. The optimum conditions were determined as: trypsin concentration at 1.49 U/g; extraction temperature at 45 °C; and extraction time at 6 h 16 min. This response surface optimized model was significant and produced an experimental value (202.04 ± 8.64%) in good agreement with the predicted value (204.19%). Twofold higher yields of gelatin with high molecular weight protein chains were achieved in the optimized process with trypsin treatment when compared to the process without trypsin.

Divergent trends in life-history traits between Atlantic salmon Salmo salar of wild and hatchery origin in the Baltic Sea.

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Vainikka, A; Kallio-Nyberg, I; Heino, M; Koljonen, M-L

2010-02-01

Four Atlantic salmon Salmo salar stocks in the Baltic Sea, varying in their breeding history, were studied for changes in life-history traits over the years 1972-1995. Total length (L(T)) at age of captured (L(TC)) fish had increased throughout the study period, partly due to increased temperature and increased L(T) at release, (L(TR)) but also due to remaining cohort effects that could represent unaccounted environmental or genetic change. Simultaneously, maturation probabilities controlled for water temperature, L(TC) and L(TR) had increased in all stocks. The least change was observed in the River Tornionjoki S. salar that was subject only to supportive stockings originating from wild parents. These results suggest a long-term divergence between semi-natural and broodstock-based S. salar stocks. Increased L(T) at age explained advanced maturation only marginally, and it remains an open question to what extent the generally increased probabilities to mature at early age reflected underlying genetic changes.

The accumulation of radioactive caesium from water by the brown trout (Salmo trutta) and its comparison with plaice and rays

International Nuclear Information System (INIS)

Hewett, C.J.; Jefferies, D.F.

1976-01-01

The patterns of accumulation of caesium-137 from water by the tissues and organs of the freshwater teleost, the brown trout (Salmo trutta) are described. Estimates of the biological half-times and steady-state concentrations are derived, using a simple exponential equation. In all tissues and organs examined, other than muscle, the rate processes of the trout fall between those of the plaice and the ray. It is concluded that most of the caesium accumulated by the brown trout from water enters other than by the gut, probably through the gills, but as with plaice and ray, the main source of the caesium, possibly 90%, must come from the food. Despite differences in the levels of accumulation, the ratios of the tissue to blood steady state concentrations were very similar in all three species. The steady state caesium concentration of the blood appeared to be directly related to the red blood cell count of the fish. (author)

Effect of potassium ethylxanthate and sodium diethyldithiocarbamate on the accumulation and disposition of nickel in the brown trout (salmo trutta)

International Nuclear Information System (INIS)

Gottofrey, J.; Borg, K.; Jasim, S.; Tjaelve, H.

1988-01-01

Brown trouts, Salmo trutta, were exposed to water containing 0.1 or 10 μg/1 of 63 Ni 2+ , alone or with potassium ethylxanthate or sodium diethyldithiocarbamate. After one and three weeks the accumulation and disposition of the 63 Ni 2+ in the fish were examined by liquid scintillation spectrometry and whole-body autoradiography. The sodium diethyldithiocarbamate was found to greatly enhance the uptake of 63 Ni 2+ in several tissues of the trouts. Potassium ethylxanthate was without effect. Diethyldithiocarbamate is known to form lipophilic complexes with metals, including nickel, and a facilitated penetration of the complexed nickel over the cellular membranes of the gills and other tissues is a likely mechanism underlying our results. The ethylxanthate is also able to form a lipophilic nickel-chelate, although of a lower lipophilicity than the nickel-diethyldithiocarbamate-complex. This variance in lipophilicity may explain why the disposition of the 63 Ni 2+ was affected by the diethyldithiocarbamate, but not by the ethylxanthate. (author)

Breaking the speed limit--comparative sprinting performance of brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta)

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Castro-Santos, Theodore; Sanz-Ronda, Francisco Javier; Ruiz-Legazpi, Jorge

2013-01-01

Sprinting behavior of free-ranging fish has long been thought to exceed that of captive fish. Here we present data from wild-caught brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta), volitionally entering and sprinting against high-velocity flows in an open-channel flume. Performance of the two species was nearly identical, with the species attaining absolute speeds > 25 body lengths·s−1. These speeds far exceed previously published observations for any salmonid species and contribute to the mounting evidence that commonly accepted estimates of swimming performance are low. Brook trout demonstrated two distinct modes in the relationship between swim speed and fatigue time, similar to the shift from prolonged to sprint mode described by other authors, but in this case occurring at speeds > 19 body lengths·s−1. This is the first demonstration of multiple modes of sprint swimming at such high swim speeds. Neither species optimized for distance maximization, however, indicating that physiological limits alone are poor predictors of swimming performance. By combining distributions of volitional swim speeds with endurance, we were able to account for >80% of the variation in distance traversed by both species.

Impacts of episodic acidification on in-stream survival and physiological impairment of Atlantic salmon (Salmo salar) smolts

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McCormick, S.D.; Keyes, A.; Nislow, K.H.; Monette, M.Y.

2009-01-01

We conducted field studies to determine the levels of acid and aluminum (Al) that affect survival, smolt development, ion homeostasis, and stress in Atlantic salmon (Salmo salar) smolts in restoration streams of the Connecticut River in southern Vermont, USA. Fish were held in cages in five streams encompassing a wide range of acid and Al levels for two 6-day intervals during the peak of smolt development in late April and early May. Physiological parameters were unchanged from initial sampling at the hatchery and the high water quality reference site (pH > 7.0, inorganic Al pH (5.4-5.6) and highest inorganic Al (50-80 μg·L-1). Moderate loss of plasma chloride, increased plasma cortisol and glucose, and moderately elevated gill Al occurred at less severely impacted sites. Gill Al was a better predictor of integrated physiological impacts than water chemistry alone. The results indicate that Al and low pH under field conditions in some New England streams can cause mortality and impair smolt development in juvenile Atlantic salmon and provide direct evidence that episodic acidification is impacting conservation and recovery of Atlantic salmon in the northeastern USA.

Sperm motility in fishes. (II) Effects of ions and osmolality: a review.

Science.gov (United States)

Alavi, Sayyed Mohammad Hadi; Cosson, Jacky

2006-01-01

The spermatozoa of most fish species are immotile in the testis and seminal plasma. Therefore, motility is induced after the spermatozoa are released into the aqueous environment during natural reproduction or into the diluent during artificial reproduction. There are clear relationships between seminal plasma composition and osmolality and the duration of fish sperm motility. Various parameters such as ion concentrations (K+, Na+, and Ca2+), osmotic pressure, pH, temperature and dilution rate affect motility. In the present paper, we review the roles of these ions on sperm motility in Salmonidae, Cyprinidae, Acipenseridae and marine fishes, and their relationship with seminal plasma composition. Results in the literature show that: 1. K+ is a key ion controlling sperm motility in Salmonidae and Acipenseridae in combination with osmotic pressure; this control is more simple in other fish species: sperm motility is prevented when the osmotic pressure is high (Cyprinidae) or low (marine fishes) compared to that of the seminal fluid. 2. Cations (mostly divalent, such as Ca2+) are antagonistic with the inhibitory effect of K+ on sperm motility. 3. In many species, Ca2+ influx and K+ or Na+ efflux through specific ionic channels change the membrane potential and eventually lead to an increase in cAMP concentration in the cell, which constitutes the initiation signal for sperm motility in Salmonidae. 4. Media that are hyper- and hypo-osmotic relative to seminal fluid trigger sperm motility in marine and freshwater fishes, respectively. 5. The motility of fish spermatozoa is controlled through their sensitivity to osmolality and ion concentrations. This phenomenon is related to ionic channel activities in the membrane and governs the motility mechanisms of axonemes.

COMPARAÇÃO ENTRE OS MÉTODOS DE EXTRAÇÃO DE METACERCÁRIAS DE ASCOCOTYLE SP (TREMATODA: DIGENEA DOS TECIDOS DE MUGIL LIZA VALENCIENNES, 1836 (TELEOSTEI: MUGILIDAE

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Renato Ribeiro Nogueira Ferraz

2014-09-01

Full Text Available The demand and consumption of fish and their derivatives has increased considerably in recent years. However, fish are ideal hosts of numerous parasites, highlighting the need to develop new research methodologies for its detection. The aim of present study was to compare the efficacy of Ascocotyle metacercariae (Trematoda: Digenea extraction from visceral tissues of Mugil liza Valenciennes, 1836 (Teleostei: Mugilidae by two methods: homogenization by blender or mixer. Twentysix samples of M. liza were collected, being 16 liver samples and 10 samples of muscle tissue. Approximately 5g of each sample were processed by blender and mixer techniques homogenization for metacercariae extraction. In liver samples, up to 46 metacercariae were found in samples homogenized in blender. The lowest amount found was 2 metacercariae for blender and mixer techniques. In samples of muscle tissue, 4 metacercariae were observed in the mixer extraction. The lowest amount was found to be 2 parasites to blender and mixer. The mean metacercariae found and extracted from muscle tissue were 0.2 (+0.357 and 1.2 (+0.963 for blender and mixer, respectively. The averages of metacercariae found and extracted from fish liver, in blender and mixer, were 24 (+15.145 and 18 (+8.246, respectively. The homogenization techniques for blender and mixer were effective for the extraction of metacercariae of mullet fish tissues, suggesting that they may be directly applicable in the field of study, especially due to the ease of testing.

Applying Fourier Transform Mid Infrared Spectroscopy to Detect the Adulteration of Salmo salar with Oncorhynchus mykiss

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Moreira, Maria João

2018-01-01

The aim of this study was to evaluate the potential of Fourier transform infrared (FTIR) spectroscopy coupled with chemometric methods to detect fish adulteration. Muscles of Atlantic salmon (Salmo salar) (SS) and Salmon trout (Onconrhynchus mykiss) (OM) muscles were mixed in different percentages and transformed into mini-burgers. These were stored at 3 °C, then examined at 0, 72, 160, and 240 h for deteriorative microorganisms. Mini-burgers was submitted to Soxhlet extraction, following which lipid extracts were analyzed by FTIR. The principal component analysis (PCA) described the studied adulteration using four principal components with an explained variance of 95.60%. PCA showed that the absorbance in the spectral region from 721, 1097, 1370, 1464, 1655, 2805, to 2935, 3009 cm−1 may be attributed to biochemical fingerprints related to differences between SS and OM. The partial least squares regression (PLS-R) predicted the presence/absence of adulteration in fish samples of an external set with high accuracy. The proposed methods have the advantage of allowing quick measurements, despite the storage time of the adulterated fish. FTIR combined with chemometrics showed that a methodology to identify the adulteration of SS with OM can be established, even when stored for different periods of time. PMID:29621135

Heavy metal contamination and hepatic toxicological responses in brown trout (Salmo trutta from the Kerguelen Islands

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Ali Jaffal

2015-09-01

Full Text Available The Kerguelen Islands include various species of freshwater fish such as brown trout (Salmo trutta. These trout are among the most isolated from direct anthropogenic impact worldwide. This study was designed to analyse cadmium (Cd and copper (Cu concentrations in the liver of Kerguelen brown trout, and to assess the possible impacts of these metals on hepatic histopathology and oxidative stress parameters (superoxide dismutase and catalase activity and glutathione levels. Trout were caught in the Château River, the Studer Lakes and the Ferme Pond, close to the scientific station of the Kerguelen Islands, corresponding to three morphotypes (river, lake and station. Kerguelen trouts’ hepatic concentrations of Cd and Cur were similar to those reported in previous studies in salmonids populations from areas under anthropological impacts. Clear hepatic disturbances (fibrosis, nuclear alteration, increased immune response, melanomacrophage centres [MMCs] were observed in all tested trout. A similar histo-pathological trend was observed among the trout from the three morphotypes but anti-oxidative responses were higher in the trout from the “station” morphotype. Hepatic alterations and the presence of MMCs in the livers of Kerguelen brown trout may be related to the high levels of Cd and Cu measured in this fish at all sampling sites.

Population size structure indices and growth standards for Salmo (trutta trutta Linnaeus, 1758 in Central Italy

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Pedicillo G.

2010-10-01

Full Text Available The purpose of this study was to provide reference data on the growth and population structure of brown trout Salmo (trutta trutta Linnaeus, in Central Italy. Standards for growth (percentiles and a standard growth model were developed from the von Bertalanffy growth model by using length-at-age data obtained from 122 sampling sites in the River Tiber basin. Length-frequency indices provide a numeric estimation for deviations of the population structure from a balanced population. We adapted the traditional North American Relative Stock Density (RSD and Proportional Stock Density (PSD indices to brown trout populations in Central Italy by means of two methods. In the first method, the benchmarks of length categories were established by using percentages applied to the largest individual in the dataset. In the second method, asymptotic length and size at maturity were used to define the length categories for index calculation. Both methods were tested on length-frequency data from 263 sampling sites in the River Tiber basin. The results showed that the PSD calculated by the first method provided a better insight into the population structures of brown trout. These results provide tools that will help ichthyologists and fish managers to compare the growth and population structure of brown trout throughout Central Italy.

Cold-water fishes and climate change in North America

Science.gov (United States)

J. E. Williams; Daniel Isaak; J. Imhof; D. A. Hendrickson; J. R. McMillan

2015-01-01

Trout, salmon, grayling and whitefishes (Salmonidae) are among the most ecologically and economically important fishes. They also are among the most vulnerable to global warming, and increasing drought, floods, and wildfires. In North America, salmonids occur from central Mexico northward along coastal regions and mountainous interiors to the Arctic Plains. A...

From the viral perspective: infectious salmon anemia virus (ISAV) transcriptome during the infective process in Atlantic salmon (Salmo salar).

Science.gov (United States)

Valenzuela-Miranda, Diego; Cabrejos, María Eugenia; Yañez, José Manuel; Gallardo-Escárate, Cristian

2015-04-01

The infectious salmon anemia virus (ISAV) is a severe disease that mainly affects the Atlantic salmon (Salmo salar) aquaculture industry. Although several transcriptional studies have aimed to understand Salmon-ISAV interaction through the evaluation of host-gene transcription, none of them has focused their attention upon the viral transcriptional dynamics. For this purpose, RNA-Seq and RT-qPCR analyses were conducted in gills, liver and head-kidney of S. salar challenged by cohabitation with ISAV. Results evidence the time and tissue transcript patterns involved in the viral expression and how the transcription levels of ISAV segments are directly linked with the protein abundance found in other virus of the Orthomyxoviridae family. In addition, RT-qPCR result evidenced that quantification of ISAV through amplification of segment 3 would result in a more sensitive approach for detection and quantification of ISAV. This study offers a more comprehensive approach regarding the ISAV infective process and gives novel knowledge for its molecular detection. Copyright © 2014 Elsevier B.V. All rights reserved.

An Evaluation of Molybdenum Toxicity to the Oligochaete, Tubifex tubifex, and Early-Life Stages of Brown Trout, Salmo trutta.

Science.gov (United States)

Lucas, Brett T; Quinteros, Claudio; Burnett-Seidel, Charlene; Elphick, James R

2017-06-01

Limited data are available describing the aquatic toxicity of molybdenum in freshwater environments, making it difficult to assess the aquatic risk to freshwater organisms. In order to increase available information on the aquatic toxicity of molybdenum, a 96-h LC50 test with the oligochaete Tubifex tubifex and an 85-day development test using brown trout, Salmo trutta, were conducted. The T. tubifex test resulted in an LC50 value of 2782 mg/L. No adverse effects were observed on brown trout survival or length in the concentrations tested, however an IC10 value for growth (wet weight) was determined to be 202 mg/L. Whole body fish tissue concentrations for molybdenum increased in all treatment concentrations tested, although bioconcentration factors decreased at greater exposure concentrations, and ranged from 0.13 at an exposure concentration of 20 mg/L to 0.04 at an exposure of 1247 mg/L. A body burden of 26.0 mg/kg was associated with reduced wet weight.

Experimental tests for heritable morphological color plasticity in non-native brown trout (Salmo trutta populations.

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Peter A H Westley

Full Text Available The success of invasive species is frequently attributed to phenotypic plasticity, which facilitates persistence in novel environments. Here we report on experimental tests to determine whether the intensity of cryptic coloration patterns in a global invader (brown trout, Salmo trutta was primarily the result of plasticity or heritable variation. Juvenile F1 offspring were created through experimental crosses of wild-caught parents and reared for 30 days in the laboratory in a split-brood design on either light or dark-colored gravel substrate. Skin and fin coloration quantified with digital photography and image analysis indicated strong plastic effects in response to substrate color; individuals reared on dark substrate had both darker melanin-based skin color and carotenoid-based fin colors than other members of their population reared on light substrate. Slopes of skin and fin color reaction norms were parallel between environments, which is not consistent with heritable population-level plasticity to substrate color. Similarly, we observed weak differences in population-level color within an environment, again suggesting little genetic control on the intensity of skin and fin colors. Taken as whole, our results are consistent with the hypothesis that phenotypic plasticity may have facilitated the success of brown trout invasions and suggests that plasticity is the most likely explanation for the variation in color intensity observed among these populations in nature.

Remodeling of the notochord during development of vertebral fusions in Atlantic salmon (Salmo salar).

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Ytteborg, Elisabeth; Torgersen, Jacob Seilø; Pedersen, Mona E; Baeverfjord, Grete; Hannesson, Kirsten O; Takle, Harald

2010-12-01

Histological characterization of spinal fusions in Atlantic salmon (Salmo salar) has demonstrated shape alterations of vertebral body endplates, a reduced intervertebral space, and replacement of intervertebral cells by ectopic bone. However, the significance of the notochord during the fusion process has not been addressed. We have therefore investigated structural and cellular events in the notochord during the development of vertebral fusions. In order to induce vertebral fusions, Atlantic salmon were exposed to elevated temperatures from fertilization until they attained a size of 15g. Based on results from radiography, intermediate and terminal stages of the fusion process were investigated by immunohistochemistry and real-time quantitative polymerase chain reaction. Examination of structural extracellular matrix proteins such as Perlecan, Aggrecan, Elastin, and Laminin revealed reduced activity and reorganization at early stages in the pathology. Staining for elastic fibers visualized a thinner elastic membrane surrounding the notochord of developing fusions, and immunohistochemistry for Perlecan showed that the notochordal sheath was stretched during fusion. These findings in the outer notochord correlated with the loss of Aggrecan- and Substance-P-positive signals and the further loss of vacuoles from the chordocytes in the central notochord. At more progressed stages of fusion, chordocytes condensed, and the expression of Aggrecan and Substance P reappeared. The hyperdense regions seem to be of importance for the formation of notochordal tissue into bone. Thus, the remodeling of notochord integrity by reduced elasticity, structural alterations, and cellular changes is probably involved in the development of vertebral fusions.

Histochemical demonstration of mercury in the olfactory system of salmon (Salmo salar L.) following treatments with dietary methylmercuric chloride and dissolved mercuric chloride

DEFF Research Database (Denmark)

Baatrup, E; Døving, K B

1991-01-01

The deposition of organic and inorganic mercury compounds was studied histochemically in the salmon (Salmo salar L.) olfactory system. One group of salmon was given fodder pellets containing methylmercuric chloride (CH3HgCl, 99 micrograms Hg/g) for 4 weeks. Other groups of fish were exposed...... to dissolved mercuric chloride (HgCl2, 270 micrograms Hg/liter) for 2, 6, and 12 hr, respectively. In both series of experiments, the radioisotope 203Hg was included in order to determine the accumulation of mercury in the olfactory system. Gamma-spectrometry showed that both mercury compounds accumulated...... in the olfactory rosettes and their nerves. Tissue sections from the rosettes and olfactory nerves were subjected to autometallographic silver enhancement, thereby rendering mercury deposits visible for light and electron microscopy. Microscopic analysis demonstrated an intense and comprehensive Hg deposition...

The effects of swimming exercise and dissolved oxygen on growth performance, fin condition and precocious maturation of early-rearing Atlantic salmon Salmo salar

Science.gov (United States)

Waldrop, Thomas; Summerfelt, Steven T.; Mazik, Patricia M.; Good, Christopher

2018-01-01

Swimming exercise, typically measured in body-lengths per second (BL/s), and dissolved oxygen (DO), are important environmental variables in fish culture. While there is an obvious physiological association between these two parameters, their interaction has not been adequately studied in Atlantic salmon Salmo salar. Because exercise and DO are variables that can be easily manipulated in modern aquaculture systems, we sought to assess the impact of these parameters, alone and in combination, on the performance, health and welfare of juvenile Atlantic salmon. In our study, Atlantic salmon fry were stocked into 12 circular 0.5 m3 tanks in a flow-through system and exposed to either high (1.5–2 BL/s) or low (salmon early rearing can result in improved growth performance and a lower incidence of precocious parr.

The complete genome sequence of CrRV-Ch01, a new member of the family Rhabdoviridae in the parasitic copepod Caligus rogercresseyi present on farmed Atlantic salmon (Salmo salar) in Chile.

Science.gov (United States)

Økland, Arnfinn Lodden; Skoge, Renate Hvidsten; Nylund, Are

2018-06-01

We have determined the complete genome sequence of a new rhabdovirus, tentatively named Caligus rogercresseyi rhabdovirus Ch01 (CrRV-Ch01), which was found in the parasite Caligus rogercresseyi, present on farmed Atlantic salmon (Salmo salar) in Chile. The genome encodes the five canonical rhabdovirus proteins in addition to an unknown protein, in the order N-P-M-U (unknown)-G-L. Phylogenetic analysis showed that the virus clusters with two rhabdoviruses (Lepeophtheirus salmonis rhabdovirus No9 and Lepeophtheirus salmonis rhabdovirus No127) obtained from another parasitic caligid, Lepeophtheirus salmonis, present on farmed Atlantic salmon on the west coast of Norway.

A comparison of neutral and immune genetic variation in Atlantic salmon, Salmo salar L. in Chilean aquaculture facilities.

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David S Portnoy

Full Text Available Genetic diversity was assessed in samples of cultured Atlantic salmon, Salmo salar L., obtained from facilities in Chile between 2005 and 2010, a period of time during which the infectious pathogens Infectious Salmon Anemia (ISA virus, Caligus rogercresseyi (sea lice, and Piscirickettsia salmonis (salmon rickettsial syndrome were common. Two panels of microsatellite markers were utilized: one with microsatellites with no known gene associations (neutral and one featuring microsatellites linked to putative immune-related genes (immune-related. Allelic richness and gene diversity across samples were significantly greater in neutral loci as compared to immune-related loci. Both diversity measures were homogeneous among samples for immune-related loci and heterogeneous among samples for neutral loci. Immune-related loci were identified as F(ST outliers in pairwise comparisons of samples at a 10-fold higher frequency than neutral loci. These results indicate that neutral and immune-related portions of the Atlantic salmon genome may have differed in response to the gauntlet of pathogens and that monitoring of specific, well characterized immune-related loci as well as neutral loci in cultured species could be useful when disease control and prevention is a goal.

Effect of Maillard browning reaction on protein utilization and plasma amino acid response by rainbow trout (Salmo gairdneri).

Science.gov (United States)

Plakas, S M; Lee, T C; Wolke, R E; Meade, T L

1985-12-01

The effect of the Maillard browning reaction in the diet of rainbow trout (Salmo gairdneri) on growth and amino acid availability was investigated. Chemical and enzymatic hydrolysis methods were applied for the detection of the losses of amino acids in a model protein browning system. Arginine and lysine exhibited the greatest losses in the mixture of fish protein isolate and glucose stored for 40 d at 37 degrees C. The apparent digestibility and absorption of individual amino acids, particularly lysine, was lower in trout fed browned protein than in those fed the control protein. Plasma lysine levels were significantly depressed, while the plasma levels of glucose and most other amino acids were elevated in relation to the loss in nutritive value of dietary protein after browning. The early Maillard reaction derivative of lysine, epsilon-deoxy-fructosyl-lysine, was recovered from browned protein (by using the in vitro enzymatic hydrolysis procedure) and from the plasma of trout fed browned protein. Analysis of plasma free amino acids provided an indication of lysine bioavailability and identified lysine as the first-limiting amino acid in the diets containing browned protein.

Effect of feeding frequency and feeding rate on growth of ...

African Journals Online (AJOL)

Effect of feeding frequency and feeding rate on growth of Oreochromis mossambicus (Teleostei: Cichlidae) fry. ... Weight gain, specific growth rate and gross food conversion ratio were significantly affected by ... AJOL African Journals Online.

Environmental Planning Technical Report. Biological Resources

Science.gov (United States)

1984-01-01

Salmo clarki pleuriticus Colorado River cutthroat trout x Salmo clarki stomias Greenback cutthroat trout x Salmo gairdneri Rainbow trout x x x x Salmo...SnGFPD. These spec may occur within the drainages of the ROI s7able 2.5.S..1), The greenback cutthroet trout (SAlm cla.-ki stomias ) is federal-listed

Dietary soya saponins increase gut permeability and play a key role in the onset of soyabean-induced enteritis in Atlantic salmon (Salmo salar L.)

DEFF Research Database (Denmark)

Knudsen, Sven David Lausten; Jutfelt, Fredrik; Sundh, Henrik

2008-01-01

are naturally occurring amphiphilic molecules and have been associated with many biological activities. The aim of the present study was to investigate whether soya saponins trigger the onset of soyabean-induced enteritis in Atlantic salmon (Salmo salar L.), and to examine if dietary soya saponins...... increase the epithelial permeability of the distal intestine in Atlantic salmon. Seven experimental diets containing different levels of soya saponins were fed to seawater-adapted Atlantic salmon for 53 d. The diets included a fishmeal-based control diet, two fishmeal-based diets with different levels...... of added soya saponins, one diet containing 25 % lupin kernel meal, two diets based on 25 % lupin kernel meal with different levels of added soya saponins, and one diet containing 25 % defatted soyabean meal. The effect on intestinal morphology, intestinal epithelial permeability and faecal DM content...

Attempt to validate breakpoint MIC values estimated from pharmacokinetic data obtained during oxolinic acid therapy of winter ulcer disease in Atlantic salmon ( Salmo salar )

DEFF Research Database (Denmark)

Coyne, R.; Bergh, Ø.; Samuelsen, O.

2004-01-01

Concentrations of oxolinic acid (OXA) were measured in the plasma, muscle, liver, and kidney of 48 Atlantic salmons (Salmo salar) 1 day after the end of an oral administration. OXA was administered over a period of 13 days to control an outbreak of winter ulcer disease in a commercial marine farm...... administration of OXA. A numerical description of the concentration of the antimicrobial agent achieved in therapy is necessary to determine the resistance or sensitivity of the bacteria involved in the infection. The degree of fish-to-fish variation in the concentrations of OXA, both within the healthy fish...... a useful parameter for describing the concentrations of agents achieved during therapy. The plasma data from this investigation were used to estimate clinically relevant breakpoint minimum inhibitory concentration (MIC) values. The validity of these breakpoint values was discussed with reference...

Feeding of guitarfish Rhinobatos percellens (Walbaum, 1972 (Elasmobranchii, Rhinobatidae, the target of artisanal fishery in Southern Brazil

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Hugo Bornatowski

2010-03-01

Full Text Available Rhinobatos percellens is one of three species of Rhinobatidae found on Brazilian shores and is one of the most abundant species on the shallow continental shelf of Paraná and Santa Catarina States. Specimens caught by artisanal fishery between July/2001 and March/2003 by fishing communities located on the frontier between two southern Brazilian States (Paraná and Santa Catarina had their stomach contents analyzed. According to the Alimentary Index (IAi, Decapoda (69% and Teleostei (22% were the main items consumed. Polychaeta, a common prey consumed by several benthonic fishes, was poorly represented in the feeding of R. percellens. This fact may be related to the availability of prey in the environment, or to the size of the guitarfish analyzed (ontogeny. Seasonal variance of main preys (with higher IAi was observed: Dendrobranchiata and Pleocyemata displayed higher percentages in spring and autumn, Teleostei in the winter and Brachyura during the summer.Rhinobatos percellens é uma das três espécies de Rhinobatidae encontrada na costa brasileira e uma das espécies de elasmobrânquio mais abundante na plataforma continental dos estados do Paraná e Santa Catarina. Indivíduos capturados pela pesca artesanal entre Julho/2001 e Março/2003 nas comunidades pesqueiras localizadas entre o Paraná e Santa Catarina tiveram seus conteúdos estomacais analisados. O Índice de Importância Alimentar (IAi mostrou que as principais presas consumidas foram Decapoda (69% e Teleostei (22%. Polychaeta, principal presa ingerida por várias espécies de peixes bentônicos foi pouco expressiva na alimentação de R. percellens. Essa diferença pode estar relacionada com a disponibilidade de presas no ambiente ou com o tamanho das raias analisadas (ontogenia. De acordo com análises sazonais, observou-se que os camarões Dendrobranchiata e Pleocyemata foram as principais presas consumidas durante a primavera e outono, Teleostei durante o inverno e Brachyura

Distribution and elimination of [14C]octachlorostyrene in cod (Gadus morhua), rainbow trout (Salmo gairdneri), and blue mussel (Mytilus edulis)

International Nuclear Information System (INIS)

Ingebrigtsen, K.; Solbakken, J.E.; Norheim, G.; Nafstad, I.

1988-01-01

Cod (Gadus morhua) and rainbow trout (Salmo gairdneri) were given a single oral dose of 100 microCi/kg b.w. of [ 14 C]octachlorostyrene [( 14 C]OCS) in peanut oil. Blue mussel (Mytilus edulis) was exposed to [ 14 C]OCS in water. The distribution and elimination of the compound was studied by liquid scintillation counting and whole-body autoradiography. The highest degree of radioactivity in the cod and rainbow trout was measured in the liver and the visceral fat, respectively. The degree of radioactivity in the brain of cod exceeded that of the rainbow trout by a factor between 2 and 4 at all survival times. In addition to bile excretion of [ 14 C]OCS-derived radioactivity, a possible excretion over the intestinal mucosa was suggested. The rate of elimination was slow in both species, and substantial amounts of radioactivity remained in the tissues 90 d after administration. In the blue mussel, the highest degree of radioactivity was found in the hepatopancreas. Substantial amounts of radioactivity were present in the mussel tissues 60 d after administration

Water contaminated with Didymosphenia geminata generates changes in Salmo salar spermatozoa activation times.

Science.gov (United States)

Olivares, Pamela; Orellana, Paola; Guerra, Guillermo; Peredo-Parada, Matías; Chavez, Viviana; Ramirez, Alfredo; Parodi, Jorge

2015-06-01

Didimosphenia geminata ("didymo"), has become a powerful and devastating river plague in Chile. A system was developed in D. geminata channels with the purpose evaluating the effects of water polluted with didymo on the activation of Atlantic salmon (Salmo salar) spermatozoa. Results indicate that semen, when activated with uncontaminated river water had an average time of 60±21s. When using Powermilt, (a commercial activator), times of 240±21s are achieved, while rivers contaminated with D. geminata achieve a motility time of 30±12s. Interestingly enough, the kinetic parameters of VSL, VCL and VAP showed no significant changes under all of the conditions. Furthermore, the presence of D. geminata reduces activation time of the samples as the cells age, indicating increased effects in spermatozoa that are conserved for more than 5 days. D. geminata has antioxidant content, represented by polyphenols; 200ppm of polyphenol were obtained in this study per 10g of microalgae. Spermatozoa exposed to these extracts showed a reduction in mobility time in a dose dependent manner, showing an IC50 of 15ppm. The results suggest an effect on spermatozoa activation, possibly due to the release of polyphenols present in contaminated rivers, facilitating the alteration of sperm motility times, without affecting the viability or kinetics of the cells. These findings have important implications for current policy regarding the control of the algae. Current control measures focus on the number of visible species, and not on the compounds that they release, which this study shows, also have a problematic effect on salmon production. Copyright © 2015 Elsevier B.V. All rights reserved.

Distribution of radioactivity in the chondrichthyes Squalus acanthias and the osteichthyes salmo gairdneri following intragastric administration of (9-/sup 14/C)phenanthrene

Energy Technology Data Exchange (ETDEWEB)

Solbakken, J.E.; Palmork, K.H.

1980-12-01

The fate of polycyclic hydrocarbons (PAH) in marine animals has received increasing attention in the last decade. The present studies dealing with spiny dogfish (Squalus acanthias) and rainbow trout (Salmo gairdneri) are part of a series of experiments with different marine organisms. All the experiments were performed under the same laboratory conditions using intragastric administration of the PAH-component, /sup 14/C-labelled phenanthrene. Thus it is possible to compare species differences of disposition of PAH in various marine organisms. The most pronounced differences in the disposition of phenanthrene between bony fish and cartilaginous fish in our studies are that the maximum value of radioactivity in the liver of cartilaginous fish occurred several days later than the corresponding value in bony fish. Furthermore, the radioactivity in cartilaginous fish was retained at a high level beyond 672 h (28 days), a time at which the radioactivity in bony fish is near the background values.

Estrogenic effect of the phytoestrogen biochanin A in zebrafish, Danio rerio, and brown trout, Salmo trutta.

Science.gov (United States)

Holbech, Henrik; Schröder, Kristoffer D; Nielsen, Marie L; Brande-Lavridsen, Nanna; Holbech, Bente Frost; Bjerregaard, Poul

2013-11-15

Isoflavones with estrogenic activity produced in Fabaceae plants are known to leach from agricultural areas to freshwater systems, but the effect of waterborne isoflavones in fish has not been thoroughly characterized. Therefore, the estrogenic effect of waterborne biochanin A was investigated in zebrafish (Danio rerio) and juvenile brown trout (Salmo trutta). Exposure of juvenile brown trout to 10 μg biochanin AL(-1) or higher caused marked vitellogenin induction after 9-10 days of exposure and so did exposure to 186 μg biochanin AL(-1) for 6h. Following 8d of exposure, a NOEC for induction of vitellogenin production in male zebrafish was 70 and LOEC 114 μg biochanin AL(-1). Exposure to 209 μg biochanin AL(-1) from hatch to 60 days post hatch (dph) caused a skewing of the sex ratio toward more phenotypic female zebrafish, but did not cause induction of vitellogenin in male and undifferentiated fish. (1) biochanin A elicits estrogenic effects in trout at environmentally realistic concentrations, (2) brown trout plasma vitellogenin concentrations respond to lower biochanin A exposure concentrations than vitellogenin concentrations in zebrafish homogenates and (3) concerning vitellogenin induction, the hypothesis should be tested if short term tests with zebrafish may show a higher sensitivity than partial life cycle tests. Copyright © 2013 Elsevier B.V. All rights reserved.

Short Note Effect of turbidity on the foraging success of ...

African Journals Online (AJOL)

Teleostei: Gobiidae). MC Parkinson, AJ Booth. Abstract. No Abstract. African Journal of Aquatic Science 2011, 36(2): 213–216. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

Ecotoxicological impact of highway runoff using brown trout (Salmo trutta L.) as an indicator model.

Science.gov (United States)

Meland, Sondre; Salbu, Brit; Rosseland, Bjørn Olav

2010-03-01

The ecotoxicological impact of highway runoff on brown trout (Salmo trutta L.) was studied in an in situ experiment consisting of four 24 h simulated runoff episodes. Fish were maintained in 5 tanks and exposed to highway runoff from a sedimentation pond close to E6 outside the city of Oslo, Norway. The tanks had the following contaminant loadings during the episodes: stream water (control), pond inlet, pond outlet, pond inlet + stream water and pond outlet + stream water. Opposite to road salt and compared to earlier findings, the first two episodes had rather low concentrations of trace metals, hydrocarbons and polycyclic aromatic hydrocarbons. A heavy rainfall before episode 3 increased the concentrations of all the contaminants except road salt which was diluted. In addition, lowered oxygen levels led to hypoxic conditions. Overall the fish exposed to highway runoff had, compared to the control fish, higher concentrations of trace metals in gills and liver, increased activity of the antioxidant defense system represented by superoxide dismutase, catalase and metallothionein, problems with the regulation of plasma Cl and Na, as well as increased levels of blood glucose and pCO(2). Finally, this seemed to affect the metabolism of the fish through reduced condition factor. The observed effects were likely caused by multiple stressors and not by a single contaminant. The sedimentation pond clearly reduced the toxicity of the highway runoff. But even in the least polluted exposure tank (pond outlet + stream water) signs of physiological disturbances were evident.

Genetic diversity and population structure in Meconopsis ...

African Journals Online (AJOL)

STORAGESEVER

2010-05-24

May 24, 2010 ... The location and main ecological characteristics of sample sites are shown in ..... suggest that this is wind-pollinated and allogamous plant species ... (Teleostei, Characidae) from an urban stream, Hydrobiology, 553: 245-254 ...

gonads of Cheimerius nufar (Ehrenberg, 1820)

African Journals Online (AJOL)

macroscopic changes in the gonads of Cheimerius nuJar. In addition .... Cytoplasm stains darker. ..... period. All stages present; 50% of lobules with sperm; main duct full .... in five species of grey mullets (Teleostei, Mugilidae) from natural.

Mate choice for major histocompatibility complex genetic divergence as a bet-hedging strategy in the Atlantic salmon (Salmo salar)

Science.gov (United States)

Evans, Melissa L.; Dionne, Mélanie; Miller, Kristina M.; Bernatchez, Louis

2012-01-01

Major histocompatibility complex (MHC)-dependent mating preferences have been observed across vertebrate taxa and these preferences are expected to promote offspring disease resistance and ultimately, viability. However, little empirical evidence linking MHC-dependent mate choice and fitness is available, particularly in wild populations. Here, we explore the adaptive potential of previously observed patterns of MHC-dependent mate choice in a wild population of Atlantic salmon (Salmo salar) in Québec, Canada, by examining the relationship between MHC genetic variation and adult reproductive success and offspring survival over 3 years of study. While Atlantic salmon choose their mates in order to increase MHC diversity in offspring, adult reproductive success was in fact maximized between pairs exhibiting an intermediate level of MHC dissimilarity. Moreover, patterns of offspring survival between years 0+ and 1+, and 1+ and 2+ and population genetic structure at the MHC locus relative to microsatellite loci indicate that strong temporal variation in selection is likely to be operating on the MHC. We interpret MHC-dependent mate choice for diversity as a likely bet-hedging strategy that maximizes parental fitness in the face of temporally variable and unpredictable natural selection pressures. PMID:21697172

Interpopulation differences in expression of candidate genes for salinity tolerance in winter migrating anadromous brown trout (Salmo trutta L.

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Thomsen Dennis S

2008-01-01

Full Text Available Abstract Background Winter migration of immature brown trout (Salmo trutta into freshwater rivers has been hypothesized to result from physiologically stressful combinations of high salinity and low temperature in the sea. Results We sampled brown trout from two Danish populations entering different saline conditions and quantified expression of the hsp70 and Na/K-ATPases α 1b genes following acclimation to freshwater and full-strength seawater at 2°C and 10°C. An interaction effect of low temperature and high salinity on expression of both hsp70 and Na/K-ATPase α 1b was found in trout from the river entering high saline conditions, while a temperature independent up-regulation of both genes in full-strength seawater was found for trout entering marine conditions with lower salinities. Conclusion Overall our results support the hypothesis that physiologically stressful conditions in the sea drive sea-run brown trout into freshwater rivers in winter. However, our results also demonstrate intra-specific differences in expression of important stress and osmoregulative genes most likely reflecting adaptive differences between trout populations on a regional scale, thus strongly suggesting local adaptations driven by the local marine environment.

Consistent boldness behaviour in early emerging fry of domesticated Atlantic salmon (Salmo salar): Decoupling of behavioural and physiological traits of the proactive stress coping style

DEFF Research Database (Denmark)

Vaz-Serrano, J.; Ruiz-Gomez, M. L.; Gjøen, H. M.

2011-01-01

style seem to be coupled to the time to emerge of fry from spawning redds in natural populations of salmonid fishes. In the present study, behavioural and physiological traits of stress coping styles were compared two and five months after emergence in farmed Atlantic salmon (Salmo salar), using......Individual variation in the way animals cope with stressors has been documented in a number of animal groups. In general, two distinct sets of behavioural and physiological responses to stress have been described: the proactive and the reactive coping styles. Some characteristics of stress coping...... hunger, in the present study. This observation was repeated five months after emergence, demonstrating behavioural consistency over time in this trait. However, in other traits of proactive and reactive stress coping styles, such as social status, resting metabolism or post stress cortisol concentrations...

Increased backcrossing has reduced the usefulness of ...

African Journals Online (AJOL)

Increased backcrossing has reduced the usefulness of morphological and allozyme data for identifying Oreochromis niloticus , O. mossambicus (Teleostei: Cichlidae) and their hybrids in the Pafuri reach of the Luvuvhu River in the Kruger National Park, South Africa.

Toxicity of road deicing salt (NaCl) and copper (Cu) to fertilization and early developmental stages of Atlantic salmon (Salmo salar).

Science.gov (United States)

Mahrosh, Urma; Kleiven, Merethe; Meland, Sondre; Rosseland, Bjørn Olav; Salbu, Brit; Teien, Hans-Christian

2014-09-15

In many countries, salting of ice or snow covered roads may affect aquatic organisms in the catchment directly or indirectly by mobilization of toxic metals. We studied the toxicity of road deicing salt and copper (Cu) on the vulnerable early life stages of Atlantic salmon (Salmo salar), from fertilization till hatching. Controlled episodic exposure to road salt (≥ 5,000 mg/L) during fertilization resulted in reduced swelling and less percent egg survival. Exposure to Cu both during and post fertilization caused delayed hatching. Larval deformities were, however found as an additional effect, when eggs were exposed to high salt concentration (≥ 5,000 mg/L) mixed with Cu (10 μg Cu/L) during fertilization. Thus, it appears that the sensitivity of early developmental stages of Atlantic salmon increased when exposed to these stressors, and road salt application during spawning can pose threat to Atlantic salmon in water bodies receiving road runoff. The study gives insight on assessment and management of risks on Atlantic salmon population posed by road related hazardous chemicals. Copyright © 2014 Elsevier B.V. All rights reserved.

Observations sur le comportement alimentaire de la population de truites communes (Salmo trutta L. dans la rivière Estoräos, Portugal

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VALENTE A.

1990-07-01

Full Text Available L'étude du comportement alimentaire d'une population de truites, Salmo trutta L., est abor-dée dans la rivière Estoräos, au nord du Portugal. L'étude des macroinvertébrés benthiques et en dérive montre une composition comparable à celle d'autres rivières européennes. La fréquence d'occurrence des organismes proies ingérés met en évidence la diversité du choix alimentaire, plus marquée chez les poissons 1+. Le comportement alimentaire opportuniste de l'espèce est confirmé. L'analyse en composantes principales révèle des similitudes entre le spectre trophique des deux groupes d'âge étudiés. Le comportement alimentaire ne semble pas responsable des faibles croissance et densité de cette population détruites.

Anatomia Funcional e Morfometria do Intestino no Teleostei (Pisces de Água Doce Surubim (Pseudoplatystoma coruscans - Agassiz, 1829

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Seixas Filho José Teixeira de

2001-01-01

Full Text Available Os objetivos do presente trabalho foram estudar a anatomia funcional e a morfometria comparativas nos intestinos médio e no reto, do peixe Teleostei, surubim, Pseudoplatystoma coruscans (Agassiz, 1829 (Siluriformes, Siluroidei, Pimelodidae, de hábito alimentar carnívoro, em duas classes de tamanho, visando fornecer referência à nutrição para o ajuste de diferentes sistemas de alimentação artificial para essa espécie nativa. Por meio destes estudos concluiu-se que o intestino do surubim, sob o ponto de vista morfológico, deve ser denominado, de intestino médio e reto, devido a presença da valva ileorretal e da invaginação valvar intestinal entre esses segmentos. Em relação ao padrão de enrolamento do intestino, apesar do plano geral do intestino médio e do reto ter sido mantido, as alças do intestino médio apresentaram arranjo indefinido, não tendo sido determinado um arranjo-padrão para a espécie. O arranjo intestinal é compatível ao da maioria de peixes carnívoros, ou predominantemente carnívoro, uma vez que seu intestino é quase retilíneo; contudo, as circunvoluções das alças finais do intestino médio talvez possam ser vistas como adaptações a um possível regime onívoro, preferencialmente carnívoro. As pregas intestinais encontram-se mais complexas e desenvolvidas no intestino dos exemplares da segunda classe de tamanho. Procurando estabelecer relações entre o arranjo das pregas das mucosas e a velocidade de transporte do alimento no intestino médio da espécie estudada, sugere-se que o padrão longitudinal, com numerosas anastomoses retardam o avanço do alimento em sentido aboral, o que possibilita maior período digestivo e, conseqüentemente, maior aproveitamento dos nutrientes, pela exposição do material alimentar à mucosa intestinal por período maior, além de contribuir para a preparação do bolo fecal. As pregas da mucosa próxima ao ânus têm direção longitudinal, sugerindo auxílio na

Effects of nonylphenol on key hormonal balances and histopathology of the endangered Caspian brown trout (Salmo trutta caspius).

Science.gov (United States)

Shirdel, Iman; Kalbassi, Mohammad Reza

2016-01-01

Endocrine disruptor chemicals (EDCs) potentially pose a hazard to endangered species. Evaluation of the sensitivity of these species to EDCs could be helpful for protecting their populations. So, the present study investigated the adverse effects of nonylphenol, an EDC, on the endocrine hormones and histopathology of male and female juvenile Caspian brown trout (Salmo trutta caspius) following 21 days of exposure to nominal concentrations of 1, 10 and 100 μg/l. The results showed that the HSI and plasma total calcium of male and female fishes exposed to 100 μg/l nonylphenol were significantly increased compared with the control groups (P0.05). No significant effect of nonylphenol exposure was observed on male plasma TSH levels (P>0.05), whereas, in females, nonylphenol at all concentrations significantly reduced TSH levels. A bell-shaped response was observed in male and female plasma GH levels. Moreover, various histopathological lesions were observed in gill and intestine tissues of fishes exposed to different nonylphenol concentrations. These results demonstrate the high sensitivity of this endangered species to even environmentally relevant concentrations of nonylphenol. Furthermore, Caspian brown trout could be used as bioindicators reflecting the toxicity of nonylphenol. Copyright © 2016 Elsevier Inc. All rights reserved.

Maximum heart rate in brown trout (Salmo trutta fario) is not limited by firing rate of pacemaker cells.

Science.gov (United States)

Haverinen, Jaakko; Abramochkin, Denis V; Kamkin, Andre; Vornanen, Matti

2017-02-01

Temperature-induced changes in cardiac output (Q̇) in fish are largely dependent on thermal modulation of heart rate (f H ), and at high temperatures Q̇ collapses due to heat-dependent depression of f H This study tests the hypothesis that firing rate of sinoatrial pacemaker cells sets the upper thermal limit of f H in vivo. To this end, temperature dependence of action potential (AP) frequency of enzymatically isolated pacemaker cells (pacemaker rate, f PM ), spontaneous beating rate of isolated sinoatrial preparations (f SA ), and in vivo f H of the cold-acclimated (4°C) brown trout (Salmo trutta fario) were compared under acute thermal challenges. With rising temperature, f PM steadily increased because of the acceleration of diastolic depolarization and shortening of AP duration up to the break point temperature (T BP ) of 24.0 ± 0.37°C, at which point the electrical activity abruptly ceased. The maximum f PM at T BP was much higher [193 ± 21.0 beats per minute (bpm)] than the peak f SA (94.3 ± 6.0 bpm at 24.1°C) or peak f H (76.7 ± 2.4 at 15.7 ± 0.82°C) (P brown trout in vivo. Copyright © 2017 the American Physiological Society.

Effect of ectoparasite infestation density and life history stages on the swimming performance of Atlantic salmon Salmo salar

Directory of Open Access Journals (Sweden)

Samantha Bui

2016-06-01

Full Text Available To overcome sustainability obstacles and improve operations, the Atlantic salmon farming industry is testing novel approaches to production. Redistributing farm sites to offshore locations is one such solution; however, tolerance to high-current velocity sites must be considered, particularly if fish health status is compromised by parasites. We tested the effect of parasite density and life-history stage on the swimming performance of Atlantic salmon Salmo salar using a swim flume. Salmon with 3 different salmon lice Lepeophtheirus salmonis densities (0, 0.02 � 0.01 and 0.11 � 0.01 lice cm-2 [mean � SE] were tested across the 4 major life-history stages of lice (copepodid, chalimus, pre-adult and adult for critical swimming performance (Ucrit. Salmon Ucrit declined slightly by a mean of 0.04 to 0.10 body lengths s-1 with high parasite densities compared to uninfested and low densities, across the lice stages, while progression through the parasite life-history stages had little effect on swimming performance. Our results suggest that increasing infestation density of salmon lice incurs negative fitness consequences for farmed Atlantic salmon held in high-current velocity sites, with little difference in costs associated with attachment by different life-history stages of the lice.

Fish fauna of the Camp dels Ninots locality (Pliocene; Caldes de Malavella, province of Girona, Spain) - first results with notes on palaeoecology and taphonomy

Czech Academy of Sciences Publication Activity Database

Přikryl, Tomáš; Gómez de Soler, B.; Oms, O.; Roubach, S.; Blain, H-A.; Agustí, J.

2016-01-01

Roč. 28, č. 3 (2016), s. 347-357 ISSN 0891-2963 Institutional support: RVO:67985831 Keywords : Camp dels Ninots * Cyprinidae * maar lake * NE Spain * Pliocene * Teleostei Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.556, year: 2016

EFFECT OF CULTURE CONDITIONS ON REPRODUCTIVE TRAITS OF BROWN TROUT SALMO TRUTTA L.

Directory of Open Access Journals (Sweden)

RANDÁK T.

2006-07-01

Full Text Available Progeny from artificial propagation of wild brown trout (Salmo trutta L. of the Blanice river, Czech Republic, were farmed to maturity and spawned at ages three, four and five during 2002-2004. Reproductive parameters and biological quality of eggs in this farmed population were compared to those of the original wild population. ANCOVA showed no differences between wild and farmed fish in weight of eggs per female, total fecundity, or relative fecundity in any year. Significantly higher egg diameter (4.57 mm, P = 0.001 and weight (69.3 mg, P = 0.0375 were found in the wild population in 2002 and conversely in 2004, the mean egg weight was higher in the farmed population (94.7 mg, P = 0.0021. Differences in egg diameter in this year (4.64 ± 0.06 and 4.82 ± 0.06 in wild and farmed trout, respectively were close to the level of significance (P = 0.079. Mutual correlations between length or weight and studied reproductive traits were similar in both populations. Fertilization rate, duration of incubation period, egg losses during incubation and mortality of starving hatched fry were monitored in embryos and larvae of farmed population only (FxF, crosses between farmed females and wild males (FxW and wild population only (WxW. Altogether 6.3%, 5.8% and 5.4% of eggs died during incubation period in FxF, FxW and WxW, respectively. There were also no significant differences in duration of incubation period and mortality of starving fry. It can be concluded that farming conditions did not significantly affect the reproductive parameters and quality of eggs in the first generation of farmed broodstock.

Identification and characterisation of TLR18-21 genes in Atlantic salmon (Salmo salar).

Science.gov (United States)

Lee, P T; Zou, J; Holland, J W; Martin, S A M; Collet, B; Kanellos, T; Secombes, C J

2014-12-01

Teleost fish possess many types of toll-like receptor (TLR) some of which exist in other vertebrate groups and some that do not (ie so-called "fish-specific" TLRs). In this study, we identified in Atlantic salmon (Salmo salar) whole-genome shotgun (WGS) contigs seven TLRs that are not found in mammals, including six types of fish-specific TLRs (one TLR18, one TLR19, and four TLR20 members (two of which are putative soluble forms (s)) and one TLR21. Phylogenetic analysis revealed that teleost TLR19-21 are closely related with murine TLR11-TLR13, whilst teleost TLR18 groups with mammalian TLR1, 2, 6 and 10. A typical TLR protein domain structure was found in all these TLRs with the exception of TLR20b(s) and TLR20c(s). TLR-GFP expression plasmids transfected into SHK-1 cells showed that salmon TLR19, TLR20a and TLR20d were preferentially localised to the intracellular compartment. Real time PCR analysis suggested that salmon TLR19-TLR21 are mainly expressed in immune related organs, such as spleen, head kidney and gills, while TLR18 transcripts are more abundant in muscle. In vitro stimulation of primary head kidney cells with type I IFN, IFNγ and IL-1β had no impact on TLR expression. Infectious salmon anaemia virus (ISAV) infection, in vivo, down-regulated TLR20a, TLR20b(s), TLR20d and TLR21 in infected salmon kidney tissue. In contrast, up-regulation of TLR19 and TLR20a expression was found in posterior kidney in rainbow trout with clinical proliferative kidney disease (PKD). Copyright © 2014 Elsevier Ltd. All rights reserved.

The predatory impact of invasive alien smallmouth bass, Micropterus ...

African Journals Online (AJOL)

Teleostei: Centrarchidae), on indigenous fishes in a Cape Floristic Region ... The Rondegat River is home to five species of indigenous fish and is partially invaded by M. dolomieu, which has penetrated the lower river up to a waterfall barrier.

Natural selection constrains personality and brain gene expression differences in Atlantic salmon (Salmo salar).

Science.gov (United States)

Thörnqvist, Per-Ove; Höglund, Erik; Winberg, Svante

2015-04-01

In stream-spawning salmonid fishes there is a considerable variation in the timing of when fry leave the spawning nests and establish a feeding territory. The timing of emergence from spawning nests appears to be related to behavioural and physiological traits, e.g. early emerging fish are bolder and more aggressive. In the present study, emerging Atlantic salmon (Salmo salar L.) alevins were sorted into three fractions: early, intermediate and late emerging. At the parr stage, behaviour, stress responses, hindbrain monoaminergic activity and forebrain gene expression were explored in fish from the early and late emerging fractions (first and last 25%). The results show that when subjected to confinement stress, fish from the late emerging fraction respond with a larger activation of the brain serotonergic system than fish from the early fraction. Similarly, in late emerging fish, stress resulted in elevated expression of mRNA coding for serotonin 1A receptors (5-HT1A), GABA-A receptor-associated protein and ependymin, effects not observed in fish from the early emerging fraction. Moreover, fish from the early emerging fraction displayed bolder behaviour than their late emerging littermates. Taken together, these results suggest that time of emergence, boldness and aggression are linked to each other, forming a behavioural syndrome in juvenile salmon. Differences in brain gene expression between early and late emerging salmon add further support to a relationship between stress coping style and timing of emergence. However, early and late emerging salmon do not appear to differ in hypothalamus-pituitary-interrenal (HPI) axis reactivity, another characteristic of divergent stress coping styles. © 2015. Published by The Company of Biologists Ltd.

Spatial and temporal movement dynamics of brook Salvelinus fontinalis and brown trout Salmo trutta

Science.gov (United States)

Davis, L.A.; Wagner, Tyler; Barton, Meredith L.

2015-01-01

Native eastern brook trout Salvelinus fontinalis and naturalized brown trout Salmo trutta occur sympatrically in many streams across the brook trout’s native range in the eastern United States. Understanding within- among-species variability in movement, including correlates of movement, has implications for management and conservation. We radio tracked 55 brook trout and 45 brown trout in five streams in a north-central Pennsylvania, USA watershed to quantify the movement of brook trout and brown trout during the fall and early winter to (1) evaluate the late-summer, early winter movement patterns of brook trout and brown trout, (2) determine correlates of movement and if movement patterns varied between brook trout and brown trout, and (3) evaluate genetic diversity of brook trout within and among study streams, and relate findings to telemetry-based observations of movement. Average total movement was greater for brown trout (mean ± SD = 2,924 ± 4,187 m) than for brook trout (mean ± SD = 1,769 ± 2,194 m). Although there was a large amount of among-fish variability in the movement of both species, the majority of movement coincided with the onset of the spawning season, and a threshold effect was detected between stream flow and movement: where movement increased abruptly for both species during positive flow events. Microsatellite analysis of brook trout revealed consistent findings to those found using radio-tracking, indicating a moderate to high degree of gene flow among brook trout populations. Seasonal movement patterns and the potential for relatively large movements of brook and brown trout highlight the importance of considering stream connectivity when restoring and protecting fish populations and their habitats.

Baking reduces prostaglandin, resolvin, and hydroxy-fatty acid content of farm-raised Atlantic salmon (Salmo salar).

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Raatz, Susan K; Golovko, Mikhail Y; Brose, Stephen A; Rosenberger, Thad A; Burr, Gary S; Wolters, William R; Picklo, Matthew J

2011-10-26

The consumption of seafood enriched in n-3 polyunsaturated fatty acids (PUFA) is associated with a decreased risk of cardiovascular disease. Several n-3 oxidation products from eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (22:6n-3) have known protective effects in the vasculature. It is not known whether the consumption of cooked seafood enriched in n-3 PUFA causes appreciable consumption of lipid oxidation products. We tested the hypothesis that baking Atlantic salmon (Salmo salar) increases the level of n-3 and n-6 PUFA oxidation products over raw salmon. We measured the contents of several monohydroxy-fatty acids (MHFA), prostanoids, and resolvins. Our data demonstrate that baking did not change the overall total levels of MHFA. However, baking resulted in selective regioisomeric loss of hydroxy fatty acids from arachidonic acid (20:4n-6) and EPA, while significantly increasing hydroxyl-linoleic acid levels. The contents of prostanoids and resolvins were reduced several-fold with baking. The inclusion of a coating on the salmon prior to baking reduced the loss of some MHFA but had no effect on prostanoid losses incurred by baking. Baking did not decrease n-3 PUFA contents, indicating that baking of salmon is an acceptable means of preparation that does not alter the potential health benefits of high n-3 seafood consumption. The extent to which the levels of MHFA, prostanoids, and resolvins in the raw or baked fish have physiologic consequence for humans needs to be determined.

Sublethal effects in Atlantic salmon (Salmo salar) exposed to mixtures of copper, aluminium and gamma radiation

International Nuclear Information System (INIS)

Heier, Lene Sørlie; Teien, Hans Christian; Oughton, Deborah; Tollefsen, Knut-Erik; Olsvik, Pål A.; Rosseland, Bjørn Olav; Lind, Ole Christian; Farmen, Eivind; Skipperud, Lindis; Salbu, Brit

2013-01-01

The present study was designed to investigate the effects in presmolt of Atlantic salmon (Salmo salar) exposed to copper (Cu), aluminium (Al) and gamma radiation, individually or in combination. Fish were exposed for 48 h to metals added to lake water; 10, 40 and 80 μg Cu/L, 250 μg Al/L and a combination of 40 μg Cu/L and 250 μg Al/L. In addition, gamma radiation (4–70 mGy delivered over 48 h) was added as an additional exposure stressor. Selected endpoints were chosen to reveal different toxic mechanisms and included Cu and Al accumulation on gills, blood chemistry and haematological variables (plasma sodium and chloride, haematocrit, glucose), hepatic levels of reduced and oxidised glutathione (GSH and GSSG) and hepatic transcriptional response of glutathione peroxidase (GPx), gamma-glutamylcysteine synthetase (GCS), metallothionein (MT) and ubiquitin. Exposure to Cu alone resulted in gill accumulation of Cu, reduction of plasma ions and increased transcriptional response of GPx, MT and ubiquitin. Exposure to Al alone reduced plasma ion levels but did not affect any of the hepatic biomarkers except for ubiquitin. The combined metal exposure (Cu + Al) altered the GSH levels, however GPx and MT were not affected suggesting a different mode of detoxification in the combined exposure. Gamma radiation appeared to influence GSH and ubiquitin levels. The observed effects seemed to be both stressor and concentration dependent

Water chemistry and its effects on the physiology and survival of Atlantic salmon Salmo salar smolts

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Liebich, T.; McCormick, S.D.; Kircheis, D.; Johnson, K.; Regal, R.; Hrabik, T.

2011-01-01

The physiological effects of episodic pH fluctuations on Atlantic salmon Salmo salar smolts in eastern Maine, U.S.A., were investigated. During this study, S. salar smolts were exposed to ambient stream-water chemistry conditions at nine sites in four catchments for 3 and 6 day intervals during the spring S. salar smolt migration period. Plasma chloride, plasma glucose, gill aluminium and gill Na+- and K+-ATPase levels in S. salar smolts were assessed in relation to ambient stream-water chemistry during this migration period. Changes in both plasma chloride and plasma glucose levels of S. salar smolts were strongly correlated with stream pH, and S. salar smolt mortality occurred in one study site with ambient stream pH between 5??6 and 5??8 during the study period. The findings from this study suggest that physiological effects on S. salar smolts are strongly correlated with stream pH and that in rivers and streams with low dissolved organic carbon (DOC) concentrations the threshold for physiological effects and mortality probably occurs at a higher pH and shorter exposure period than in rivers with higher DOC. Additionally, whenever an acidification event in which pH drops below 5??9 coincides with S. salar smolt migration in eastern Maine rivers, there is potential for a significant reduction in plasma ions of S. salar smolts. ?? 2011 The Fisheries Society of the British Isles.

Effects of host genetics and environment on egg-associated microbiotas in brown trout (Salmo trutta).

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Wilkins, Laetitia G E; Fumagalli, Luca; Wedekind, Claus

2016-10-01

Recent studies found fish egg-specific bacterial communities that changed over the course of embryogenesis, suggesting an interaction between the developing host and its microbiota. Indeed, single-strain infections demonstrated that the virulence of opportunistic bacteria is influenced by environmental factors and host immune genes. However, the interplay between a fish embryo host and its microbiota has not been studied yet at the community level. To test whether host genetics affects the assemblage of egg-associated bacteria, adult brown trout (Salmo trutta) were sampled from a natural population. Their gametes were used for full-factorial in vitro fertilizations to separate sire from dam effects. In total, 2520 embryos were singly raised under experimental conditions that differently support microbial growth. High-throughput 16S rRNA amplicon sequencing was applied to characterize bacterial communities on milt and fertilized eggs across treatments. Dam and sire identity influenced embryo mortality, time until hatching and composition of egg-associated microbiotas, but no link between bacterial communities on milt and on fertilized eggs could be found. Elevated resources increased embryo mortality and modified bacterial communities with a shift in their putative functional potential. Resource availability did not significantly affect any parental effects on embryo performance. Sire identity affected bacterial diversity that turned out to be a significant predictor of hatching time: embryos associated with high bacterial diversity hatched later. We conclude that both host genetics and the availability of resources define diversity and composition of egg-associated bacterial communities that then affect the life history of their hosts. © 2016 John Wiley & Sons Ltd.

Winter feeding, growth and condition of brown trout Salmo trutta in a groundwater-dominated stream

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French, William E.; Vondracek, Bruce C.; Ferrington, Leonard C.; Finlay, Jacques C.; Dieterman, Douglas J.

2014-01-01

Winter can be a stressful period for stream-dwelling salmonid populations, often resulting in reduced growth and survival. Stream water temperatures have been identified as a primary mechanism driving reductions in fitness during winter. However, groundwater inputs can moderate water temperature and may reduce winter severity. Additionally, seasonal reductions in prey availability may contribute to decreased growth and survival, although few studies have examined food webs supporting salmonids under winter conditions. This study employed diet, stable isotope, and mark-recapture techniques to examine winter (November through March) feeding, growth, and condition of brown troutSalmo trutta in a groundwater-dominated stream (Badger Creek, Minnesota, USA). Growth was greater for fish ≤ 150 mm (mean = 4.1 mg g−1 day−1) than for those 151–276 mm (mean = 1.0 mg g−1 day−1) during the winter season. Overall condition from early winter to late winter did not vary for fish ≤150 mm (mean relative weight (Wr) = 89.5) and increased for those 151–276 mm (mean Wr = 85.8 early and 89.4 late). Although composition varied both temporally and by individual, brown trout diets were dominated by aquatic invertebrates, primarily Amphipods, Dipterans, and Trichopterans. Stable isotope analysis supported the observations of the dominant prey taxa in stomach contents and indicated the winter food web was supported by a combination of allochthonous inputs and aquatic macrophytes. Brown trout in Badger Creek likely benefited from the thermal regime and increased prey abundance present in this groundwater-dominated stream during winter.

Morphological Traits of Brown Trout (Salmo Trutta Fario from Fiad Trout Farm, Bistrița-Năsăud County

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Paul UIUIU

2017-11-01

Full Text Available The purpose of this this study was to complete the data from the specialized literature regarding some morphological charactersof male and female breeders of brown trout (Salmo trutta fario, exploited in Fiad trout farm, Bistrița-Năsăud County, Romania. The body mass (Bm of males ranged from 0.67 kg to 1.39 kg with a mean value of 0.96 ±0.07 kg. The body mass of females (Bm ranged from 0.50 kg to 0.90 kg with a mean value of 0.73±0.04 kg. In terms of descriptive statistics, the values of variability of studied characters, both males and females, are low. This low variability, shows the existence of a good homogeneity of the breeding group from Fiad trout farm.The One-Way ANOVA analysis showed that there is no statistically significance difference for the means of studied characters, except for commercial length and small perimeter of fishes. The results of t-test for showed that there is a statistically significance difference between the measurements and the gender of the specimens.

Gill pathology in Scottish farmed Atlantic salmon, Salmo salar L., associated with the microsporidian Desmozoon lepeophtherii Freeman et Sommerville, 2009.

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Matthews, C G G; Richards, R H; Shinn, A P; Cox, D I

2013-10-01

Gill disorders have emerged in recent years as a significant problem in the production of marine-stage Atlantic salmon Salmo salar L. The multi-aetiological condition 'proliferative gill inflammation' (PGI) has been reported to cause heavy losses in western Norway, yet reports of Scottish cases of the disease have remained anecdotal. In the present study, histopathological material from a marine production site in the Scottish Highlands experiencing mortalities due to a seasonal gill disease with proliferative-type pathology was examined using light microscopy, special staining techniques and transmission electron microscopy (TEM). The microsporidian Desmozoon lepeophtherii Freeman et Sommerville, 2009 (syn. Paranucleospora theridion) was identified by staining using a Gram Twort method and TEM associated with distinctive proliferative and necrotic pathology confined to the interlamellar Malpighian cell areas of the primary filaments. Epitheliocystis was not a feature of the gill pathology observed. It is believed this is the first report of D. lepeophtherii being identified associated with pathology in a Scottish gill disease case, and supports anecdotal reports that a disease at least partly synonymous with PGI as described by Norwegian researchers is present in Scottish aquaculture. © 2013 John Wiley & Sons Ltd.

Dévalaison et survie d'alevins de saumon atlantique (Salmo salar L. en milieu semi-naturel contrôlé

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BEALL E.

1983-04-01

Full Text Available Dans un chenal artificiel expérimental, des œufs de saumon atlantique (Salmo salar L. ont été pondus naturellement ou ont été enfouis au stade embryonné. A la fin de la résorption de la vésicule, une fraction importante des alevins survivants dévale de la zone de frayère. La dévalaison semble stimulée par des baisses de niveau ou des hausses de température et ralentie en période de pleine lune. D'autres facteurs pouvant être responsables de cette dévalaison sont discutés. La survie jusqu'à la collecte de tous les alevins est estimée à 74 p. 100 pour les sujets issus de la reproduction naturelle et est égale à 80 p. 100 pour ceux issus d'œufs introduits dans le gravier au stade embryonné. Des comparaisons entre ces résultats et ceux obtenus dans d'autres chenaux de fraie ou en milieu naturel montrent la validité de cette méthode pour la production d'alevins de saumon atlantique destinés au repeuplement.

Seasonal and sex-related variations in serum steroid hormone levels in wild and farmed brown trout Salmo trutta L. in the north-west of Spain.

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Fregeneda-Grandes, Juan M; Hernández-Navarro, Salvador; Fernandez-Coppel, Ignacio A; Correa-Guimaraes, Adriana; Ruíz-Potosme, Norlan; Navas-Gracia, Luis M; Aller-Gancedo, J Miguel; Martín-Gil, Francisco J; Martín-Gil, Jesús

2013-12-01

Serum steroid profiles were investigated in order to evaluate the potential use of circulating sex steroid levels as a tool for sex identification in brown trout. Changes in the serum concentrations of testosterone (T), progesterone (P), 17-β-estradiol (E2), and cortisol (F) in wild and farmed mature female and male brown trout, Salmo trutta L., were measured in each season (January, May, July, and October) in six rivers and four hatcheries located in the north-west of Spain. Serum cortisol levels in farmed brown trout were significantly higher and showed a seasonal pattern opposite to that found in wild trout. Because levels of the hormones under study can be affected by disruptive factors such as exposure to phytoestrogens (which alters the hypothalamic-pituitary-gonadal axis) and infection with Saprolegnia parasitica (which alters the hypothalamic-pituitary-adrenal axis), both factors are taken into account.

Phase difference between calcification and organic matrix formation in the diurnal growth of otoliths in rainbow trout, Salmo gairdneri

International Nuclear Information System (INIS)

Mugiya, Y.

1987-01-01

The relative role of calcium and organic matrix deposition in the formation of daily increments in otoliths was studied in in vitro preparations of otolith-containing sacculi of rainbow trout, Salmo gairdneri. Sacculi were incubated in a Ringer solution containing both 45 Ca and 3 H-glutamic acid for 2 hours at 6-h intervals throughout a 24-h period and then the uptake of these isotopes was determined for both otolith and saccular tissue fractions. Serum calcium and sodium concentrations were also analyzed for diurnal variations. Serum calcium concentrations varied diurnally by 8% in a single phasic pattern, reaching a peak at dusk (1600 h) and a nadir at night (2200 h), while sodium concentrations remained almost constant throughout a 24-h period. Diurnal variation in the otolith's uptake of calcium and glutamic acid showed discrete, antiphasic cycles. The rate of calcium uptake varied in a pattern closely resembling that of serum calcium (the peak at 1600 h and the nadir at 2200 h); glutamic acid uptake remained almost constant during the daytime and peaked at night (2200 h). The results indicate that in rainbow trout daily increments of otoliths are formed by the antiphasic deposition of calcium and organic matrix

Errata. Notes on development of the Oligocene trachinid Trachinus minutus (Jonet, 1958). (Palaeontographica, Abteilung A: Palaozoologie - Stratigraphie (2017) 308:1 DOI: 10.1127/pala/308/2017/69)

Czech Academy of Sciences Publication Activity Database

Přikryl, Tomáš

2017-01-01

Roč. 308, 4/6 (2017), s. 177-177 ISSN 0375-0442 R&D Projects: GA ČR GP13-19250P Institutional support: RVO:67985831 Keywords : Erratum * Teleostei * osteology * ontogeny * Oligocene Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.615, year: 2016

Determinação do sistema endócrino difuso nos intestinos de três Teleostei (Pisces de água doce com hábitos alimentares diferentes

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Seixas Filho José Teixeira de

2001-01-01

Full Text Available O objetivo do presente trabalho foi o de verificar a presença de células endócrinas nos intestinos médio e posterior, ou reto, e nos cecos pilóricos de três espécies tropicais de peixes Teleostei de água doce com hábitos alimentares diferentes: piracanjuba, (Brycon orbignyanus e piau (Leporinus friderici, onívoro; e surubim (Pseudoplatystoma coruscans, carnívoro. Para tanto, foram utilizados sete exemplares da piracanjuba, com médias de peso e comprimento-padrão de 410,16 ± 66,33 g e 27,42 ± 1,17 cm, respectivamente, 13 exemplares de piau com médias de 77,71 ± 24,31 g e 14,84 ± 1,56 cm de peso e comprimento-padrão, respectivamente; e cinco exemplares do surubim com médias de peso e comprimento-padrão de 309,91 ± 94,23 g e 32,70 ± 1,79 cm, respectivamente. Pode-se constatar a presença de células endócrinas do "tipo aberto" nos segmentos referentes aos intestinos médio e posterior das espécies onívoras e do "tipo fechado" no intestino médio e no reto da espécie carnívora. As células argirófilas foram observadas entre as células absortivas do epitélio intestinal. Os resultados permitem concluir que a presença de células endócrinas nas espécies estudadas pode indicar que estas atuam no mecanismo de controle da absorção dos nutrientes do alimento.

First evidence of the pore-forming properties of a keratin from skin mucus of rainbow trout (Oncorhynchus mykiss, formerly Salmo gairdneri).

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Molle, Virginie; Campagna, Sylvie; Bessin, Yannick; Ebran, Nathalie; Saint, Nathalie; Molle, Gérard

2008-04-01

The epidermis of fish is covered with a layer of mucus, which contributes to the defence of the species against parasites, bacteria and fungi. We have previously extracted glycoproteins from various mucus samples from fish and have shown that they present pore-forming activities well correlated with strong antibacterial properties [Ebran, Julien, Orange, Saglio, Lemaitre and Molle(2000) Biochim. Biophys. Acta 1467, 271-280]. The present study focuses on the 65 kDa glycoprotein, Tr65, from the rainbow trout (Oncorhynchus mykiss, formerly Salmo gairdneri).Enzymatic digestion of Tr65 yielded a fragment pattern with strong homology with that of trout type II cytokeratin. Sequence analysis of the cDNA clone obtained by PCR confirmed this homology. We thus constructed a plasmid to overproduce the recombinant Tr65. We extracted and purified this recombinant Tr65, using it for multichannel and single-channel experiments in azolectin bilayers. Our results with recombinant Tr65 confirmed the pore-forming properties already shown with native antibacterial Tr65. These findings offer new insights into the function of keratin proteins present in various mucosal surfaces of animals and human beings.

The effects of swimming exercise and dissolved oxygen on growth performance, fin condition and precocious maturation of early-rearing Atlantic salmon Salmo salar

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Waldrop, Thomas; Summerfelt, Steven T.; Mazik, Patricia M.; Good, Christopher

2018-01-01

Swimming exercise, typically measured in body-lengths per second (BL/s), and dissolved oxygen (DO), are important environmental variables in fish culture. While there is an obvious physiological association between these two parameters, their interaction has not been adequately studied in Atlantic salmon Salmo salar. Because exercise and DO are variables that can be easily manipulated in modern aquaculture systems, we sought to assess the impact of these parameters, alone and in combination, on the performance, health and welfare of juvenile Atlantic salmon. In our study, Atlantic salmon fry were stocked into 12 circular 0.5 m3 tanks in a flow-through system and exposed to either high (1.5–2 BL/s) or low (exercise and DO concentration on growth, feed conversion, survival and fin condition. By study's end, both increased swimming speed and higher DO were independently associated with a statistically significant increase in growth performance (p exercise and dissolved oxygen at saturation during Atlantic salmon early rearing can result in improved growth performance and a lower incidence of precocious parr.

The sexually dimorphic adipose fin is an androgen target tissue in the brown trout (Salmo trutta fario).

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Hisar, Olcay; Sönmez, Adem Yavuz; Hisar, Şükriye Aras; Budak, Harun; Gültepe, Nejdet

2013-04-01

An investigation has been described on the relationship of body length, age and sex with adipose fin length and the number of androgen receptor (AR)-containing cells in the adipose fin as a secondary sexual characteristic for brown trout (Salmo trutta fario). Firstly, body and adipose fin lengths of 2- to 5-year-old brown trout were measured. Thereafter, these fish were killed by decapitation, then their sexes were determined, and adipose fins were excised. The cellular bases of AR binding activities in the adipose fins were analyzed with an antibody against human/rat AR peptide. Immunocytochemistry and western blotting techniques were performed with this antibody. Analysis of morphological measurements indicated that body length and age had a linear relationship with adipose fin length. The coefficients of determination for the body length and age were 0.92 and 0.85 in the male fish and 0.76 and 0.73 in the female fish against the adipose fin length, respectively. At 2 years of age, cells in the adipose fin did not exhibit AR immunoreactivity. However, AR-immunopositive cells were abundant in the adipose fin of 3- to 5-year-old fish. Moreover, the number of AR-immunopositive cells was significantly (P brown trout is a probable target for androgen action and that tissue function or development may to some extent be androgen dependent. In addition, it is likely that such an effect will be mediated by specific androgen receptors.

Intestinal Fluid Permeability in Atlantic Salmon (Salmo salar L. Is Affected by Dietary Protein Source.

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Haibin Hu

Full Text Available In Atlantic salmon (Salmo salar L., and also in other fish species, certain plant protein ingredients can increase fecal water content creating a diarrhea-like condition which may impair gut function and reduce fish growth. The present study aimed to strengthen understanding of the underlying mechanisms by observing effects of various alternative plant protein sources when replacing fish meal on expression of genes encoding proteins playing key roles in regulation of water transport across the mucosa of the distal intestine (DI. A 48-day feeding trial was conducted with five diets: A reference diet (FM in which fish meal (72% was the only protein source; Diet SBMWG with a mix of soybean meal (30% and wheat gluten (22%; Diet SPCPM with a mix of soy protein concentrate (30% and poultry meal (6%; Diet GMWG with guar meal (30% and wheat gluten (14.5%; Diet PM with 58% poultry meal. Compared to fish fed the FM reference diet, fish fed the soybean meal containing diet (SBMWG showed signs of enteritis in the DI, increased fecal water content of DI chyme and higher plasma osmolality. Altered DI expression of a battery of genes encoding aquaporins, ion transporters, tight junction and adherens junction proteins suggested reduced transcellular transport of water as well as a tightening of the junction barrier in fish fed the SBMWG diet, which may explain the observed higher fecal water content and plasma osmolality. DI structure was not altered for fish fed the other experimental diets but alterations in target gene expression and fecal water content were observed, indicating that alterations in water transport components may take place without clear effects on intestinal structure.

Radiocaesium turnover in Arctic charr (Salvelinus alpinus) and brown trout (Salmo trutta) in a Norwegian lake

International Nuclear Information System (INIS)

Forseth, T.; Ugedal, O.; Jonsson, B.; Langeland, A.; Njaastad, O.

1991-01-01

The radioactivity of brown trout (Salmo trutta L.) and Arctic charr (Salvelinus alpinus (L.)) was monitored in a Norwegian lake from 1986 to 1989. A distinct difference was observed between brown trout and Arctic charr in the accumulation of radiocaesium ( 134 Cs and 137 Cs) from the Chernobyl fallout, and the study focused on the understanding of this difference. Brown trout had a large food consumption and a corresponding high intake of radiocaesium. Excretion was 20% faster in brown trout than Arctic charr as brown trout lived at high temperatures in epilimnic water. Arctic charr had a lower food consumption (less than one-third of trout) and lived in colder meta-and hypolimnic water. Arctic charr therefore had a lower intake and slower excretion of radiocaesium. Brown trout an Arctic charr had different diets. For brown trout zoobenthos was the dominant food item, whereas Artic charr mainly fed on zooplankton. The radioactivity in the stomach contents of the two species was different in 1986, but similar for the rest of the period. Higher levels of radiocaesium in brown trout than Arctic charr in 1986 were due to a higher food consumption and more radioactive food items in its diet. The parallel development in accumulated radiocaesium through summer 1987 was probably formed by brown trout balancing a higher intake with a faster excretion. The ecological half-lives of radiocaesium in brown trout (357 days) and Arctic charr (550 days) from Lake Hoeysjoeen indicated a slow removal of the isotopes from the food webs. (author)

Schistura puncticeps, a new species of loach from Myanmar (Cypriniformes: Nemacheilidae)

Czech Academy of Sciences Publication Activity Database

Bohlen, Jörg; Šlechtová, Vendula

2013-01-01

Roč. 24, č. 1 (2013), s. 85-92 ISSN 0936-9902 R&D Projects: GA ČR GA206/08/0637 Institutional research plan: CEZ:AV0Z50450515 Keywords : Teleostei Nemacheilidae * basin Subject RIV: EG - Zoology Impact factor: 2.275, year: 2013

African Journal of Aquatic Science - Vol 30, No 2 (2005)

African Journals Online (AJOL)

Fish migrations in two seasonal streams in Zimbabwe · EMAIL FULL TEXT EMAIL FULL TEXT ... The predatory impact of invasive alien smallmouth bass, Micropterus dolomieu ... Assessing the true status of the fish species Labeo cylindricus (Peters 1868) (Teleostei: ... Aquaculture: Farming Aquatic Animals and Plants

Synopsis of fossil fish fauna from the Hermanowa locality (Rupelian; Central Paratethys; Poland): current state of knowledge

Czech Academy of Sciences Publication Activity Database

Přikryl, Tomáš; Kania, I.; Krzemiński, W.

2016-01-01

Roč. 109, č. 3 (2016), s. 429-443 ISSN 1661-8726 R&D Projects: GA ČR GP13-19250P Institutional support: RVO:67985831 Keywords : fish * Teleostei * Elasmobranchii * Paleogene * Oligocene * Paratethys Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.533, year: 2016

The barbs of Lake Tana, Ethiopia : morphological diversity and its implications for taxonomy, trophic resource partitioning, and fisheries

NARCIS (Netherlands)

Nagelkerke, L.

1997-01-01

The rediscovery of a unique species flock of cyprinid fish, its taxonomy and its feeding-biology are described. Fourteen species of barbs (Barbus spp, Cyprinidae, Teleostei) were found in highland (1800 m) Lake Tana, in northwestern Ethiopia. Lake Tana is

Gyrodactylus salinae n. sp. (Platyhelminthes: Monogenea infecting the south European toothcarp Aphanius fasciatus (Valenciennes (Teleostei, Cyprinodontidae from a hypersaline environment in Italy

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Huyse Tine

2011-06-01

Full Text Available Abstract Background Historically, non-native species of Gambusia (Poeciliidae have been used to control larval stages of the Asian tiger mosquito, Stegomyia albopicta Reinert, Harbach et Kitching, 2004 throughout Italy. The potential utility of indigenous populations of Aphanius fasciatus (Valenciennes (Teleostei: Cyprinodontidae as an appropriate alternative biological control is currently being explored. A sub-sample of ten fish collected from Cervia Saline, Italy (salinity 65 ppt; 30°C to assess their reproductive capability in captivity, harboured a moderate infection of Gyrodactylus von Nordmann, 1832 (Platyhelminthes, Monogenea. A subsequent morphological and molecular study identified this as being a new species. Results Gyrodactylus salinae n. sp. is described from the skin, fins and gills of A. fasciatus. Light and scanning electron microscopical (SEM examination of the opisthaptoral armature and their comparison with all other recorded species suggested morphological similarities to Gyrodactylus rugiensoides Huyse et Volckaert, 2002 from Pomatoschistus minutus (Pallas. Features of the ventral bar, however, permit its discrimination from G. rugiensoides. Sequencing of the nuclear ribosomal DNA internal transcribed spacers 1 and 2 and the 5.8S rRNA gene and a comparison with all species listed in GenBank confirmed they are unique and represent a new species (most similar to Gyrodactylus anguillae Ergens, 1960, 8.3% pair-wise distance based on 5.8S+ITS2. This represents the first species of Gyrodactylus to be described from Aphanius and, to date, has the longest ITS1 (774 bp sequenced from any Gyrodactylus. Additional sampling of Cervia Saline throughout the year, found G. salinae n. sp. to persist in conditions ranging from 35 ppt and 5°C in December to 65 ppt and 30°C in July, while in captivity a low level of infection was present, even in freshwater conditions (0 ppt. Conclusions The ability of G. salinae n. sp. to tolerate a wide

Atlantic salmon, Salmo salar L. are broadly susceptible to isolates representing the North American genogroups of infectious hematopoietic necrosis virus

Science.gov (United States)

Kurath, Gael; Winton, James R.; Dale, Ole B.; Purcell, Maureen K.; Falk, Knut; Busch, Robert D.

2016-01-01

Beginning in 1992, three epidemic waves of infectious hematopoietic necrosis, often with high mortality, occurred in farmed Atlantic salmon Salmo salar L. on the west coast of North America. We compared the virulence of eleven strains of infectious hematopoietic necrosis virus (IHNV), representing the U, M and L genogroups, in experimental challenges of juvenile Atlantic salmon in freshwater. All strains caused mortality and there was wide variation within genogroups: cumulative mortality for five U-group strains ranged from 20 to 100%, four M-group strains ranged 30-63% and two L-group strains varied from 41 to 81%. Thus, unlike Pacific salmonids, there was no apparent correlation of virulence in a particular host species with virus genogroup. The mortality patterns indicated two different phenotypes in terms of kinetics of disease progression and final per cent mortality, with nine strains having moderate virulence and two strains (from the U and L genogroups) having high virulence. These phenotypes were investigated by histopathology and immunohistochemistry to describe the variation in the course of IHNV disease in Atlantic salmon. The results from this study demonstrate that IHNV may become a major threat to farmed Atlantic salmon in other regions of the world where the virus has been, or may be, introduced.

Variation in wind and piscivorous predator fields affecting the survival of Atlantic salmon, Salmo salar, in the Gulf of Maine

Science.gov (United States)

Friedland, K.D.; Manning, J.P.; Link, Jason S.; Gilbert, J.R.; Gilbert, A.T.; O'Connell, A.F.

2012-01-01

Observations relevant to the North American stock complex of Atlantic salmon, Salmo salar L., suggest that marine mortality is influenced by variation in predation pressure affecting post-smolts during the first months at sea. This hypothesis was tested for Gulf of Maine (GOM) stocks by examining wind pseudostress and the distribution of piscivorous predator fields potentially affecting post-smolts. Marine survival has declined over recent decades with a change in the direction of spring winds, which is likely extending the migration of post-smolts by favouring routes using the western GOM. In addition to changes in spring wind patterns, higher spring sea surface temperatures have been associated with shifting distributions of a range of fish species. The abundance of several pelagic piscivores, which based on their feeding habits may predate on salmon post-smolts, has increased in the areas that serve as migration corridors for post-smolts. In particular, populations of silver hake, Merluccius bilinearis (Mitchell), red hake, Urophycis chuss (Walbaum), and spiny dogfish, Squalus acanthias L., increased in size in the portion of the GOM used by post-smolts. Climate variation and shifting predator distributions in the GOM are consistent with the predator hypothesis of recruitment control suggested for the stock complex.

Feeding habits of the alien brook trout Salvelinus fontinalis and the native brown trout Salmo trutta in Czech mountain streams

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Horká Petra

2017-01-01

Full Text Available Quantifying patterns of prey resource use is fundamental to identify mechanisms enabling the coexistence of related fish species. Trophic interactions between the native brown trout, Salmo trutta, and the introduced brook trout, Salvelinus fontinalis, were studied monthly from May to October in three mountain streams in Central Europe (Czech Republic. To evaluate whether the feeding habits differ between separated and coexisting populations of these species, one locality where both species coexist, and two allopatric populations of either species were studied. Across the study period, the mean stomach fullness of fish varied, being highest in spring and declining through autumn. The diet overlap (Schoener's overlap index between the species increased through the studied season (from 54.5% in July to 81.5% in October. In allopatry, both species had nearly the same feeding habits. However, in sympatry, brook trout consumed higher proportion of terrestrial invertebrates, while brown trout showed no changes either in the proportions of aquatic and terrestrial prey utilized or in the selectivity for prey categories in comparison to allopatric conditions. The dietary shift observed for brook trout, but not for brown trout, suggests that brown trout is a stronger competitor in the studied sympatric locality, leading the brook trout to change its feeding habits to reduce interspecific competition.

Notes on development of the Oligocene trachinid .i.Trachinus minutus./i. (Jonet, 1958)

Czech Academy of Sciences Publication Activity Database

Přikryl, Tomáš

2017-01-01

Roč. 308, 1-3 (2017), s. 69-87 ISSN 0375-0442 R&D Projects: GA ČR(CZ) GP13-19250P Institutional support: RVO:67985831 Keywords : Teleostei * osteology * ontogeny * Oligocene * Europe Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.615, year: 2016

African Journal of Aquatic Science - Vol 38 (2013)

African Journals Online (AJOL)

Mitochondrial and nuclear DNA reveals a complete lineage sorti ng of Glossogobius callidus (Teleostei: Gobiidae) in southern Africa · EMAIL FULL TEXT ... Determining the minimum effective dose of rotenone for eradication of alien smallmouth bass Micropterus dolomieu from a South African river · EMAIL FULL TEXT ...

Two Procamallanus (Spirocamallanus) species (Nematoda: Camallanidae) from freshwater fishes in the Lower Congo River

Czech Academy of Sciences Publication Activity Database

Moravec, František; Jirků, Miloslav

2015-01-01

Roč. 60, č. 2 (2015), s. 226-233 ISSN 1230-2821 R&D Projects: GA ČR GBP505/12/G112 Institutional support: RVO:60077344 Keywords : parasitic nematode * new species * redescription * Synodontis * Parachanna * Teleostei * Africa Subject RIV: EG - Zoology Impact factor: 1.293, year: 2015

Atlas of marine bony fish otoliths (Sagittae of Southeastern - Southern Brazil Part I: Gadiformes (Macrouridae, Moridae, Bregmacerotidae, Phycidae and Merlucciidae; Part II: Perciformes (Carangidae, Sciaenidae, Scombridae and Serranidae

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Carmen Lucia Del Bianco Rossi-Wongtschowski

2014-01-01

Full Text Available The drawings, detailed pictures, precise descriptions and measurements that characterize otoliths must be made available for studies in various areas, including taxonomy, phylogeny, ecology, fisheries, paleontology, diversity, predator-prey relationships and modeling. The Collection of Teleostei Fish Otoliths of Southeastern-Southern Brazil (COSS-Brasil of IOUSP contains 45,000 pairs of otoliths from 210 species. This publication is the first in a series that will constitute an atlas of Teleostei otoliths for southeastern-southern Brazil and presents the results of the morphologic and morphometric analyses of 11 Gadiformes and 36 Perciformes species by means of the most commonly used features, measurements and indices. Three otoliths of each species were illustrated and photographed whenever possible. The frequency of occurrence was calculated for each characteristic by total length classes (TL, and the ontogenetic differences were analyzed (multiple χ2 test; significance 0.05. Morphometric analyses were conducted for each characteristic per total length (TL class and for the whole sample, and the ontogenetic differences were analyzed.

Characterization of a rhabdovirus isolated from carpione Salmo trutta carpio in Italy

Science.gov (United States)

Bovo, G.; Olesen, N.J.; Jorgensen, P.E.V.; Ahne, W.; Winton, J.R.

1995-01-01

A virus, strain 583, was isolated from carpione Salmo trutta carpio fry exhibiting high mortality. The virus was not neutralized by rabbit antisera against the fish rhabdoviruses viral haemorrhagic septicaemia virus (VHSV), infectious hematopoietic necrosis virus, eel rhabdovirus European X, spring viraemia of carp virus or pike fry rhabdovirus, or against the birnavirus infectious pancreatic necrosis virus. The virus replicated in several fish cell lines incubated at 20 to 25*C and grew optimally in the bluegill fry (BF-2) and fathead minnow (FHM) cell lines. Electron microscopy of infected BF-2 cell cultures revealed the presence of typical rhabdovirus particles, and immunofluorescent staining was observed using various polyclonal and monoclonal antibodies (MAbs) against Egtved virus, the causative agent of viral haemorrhagic septicaemia. The staining by a MAb against the nucleoprotein (N) of VHSV was particularly strong, a MAb against the glycoprotein (G) gave a moderate reaction, whereas a second MAb against the G protein and MAbs against the matrix proteins, M_(1) and M_(2), of VHSV did not react. Fluorescence titres using 3 rabbit antisera against whole Egtved virus varied between negative and moderately positive. Western blotting using polyclonal and monoclonal sera confirmed that both the N and G proteins of the carpione virus shared some epitopes with those of VHSV, but the M_(1) and M_(2) proteins did not. SDS-PAGE showed the structural proteins of the carpione virus produced a pattern typical of members of the Lyssavirus genus of the Rhabdoviridae and the molecular weights were very similar to those of VHSV, except for the M_(2) protein which was somewhat smaller. Infection trials showed the carpione virus induced high mortalities in carpione fry but not in rainbow trout Oncorhynchus mykiss fry. The carpione virus was clearly distinguishable from Egtved virus despite limited serological cross reaction. Since it was also easily distinguishable by

Detection of emamectin benzoate tolerance emergence in different life stages of sea lice, Lepeophtheirus salmonis, on farmed Atlantic salmon, Salmo salar L.

Science.gov (United States)

Jones, P G; Hammell, K L; Gettinby, G; Revie, C W

2013-03-01

Emamectin benzoate has been used to treat sea lice, Lepeophtheirus salmonis, infestations on farmed Atlantic salmon, Salmo salar. Recent evidence suggests a reduction in effectiveness in some locations. A major challenge in the detection of tolerance emergence can be the typically low proportion of resistant individuals in a population during the early phases. The objectives of this study were to develop a method for determining differences in temporal development of tolerance between sea lice life stages and to explore how these differences might be used to improve the monitoring of treatment effectiveness in a clinical setting. This study examined two data sets based on records of sea lice abundance following emamectin benzoate treatments from the west coast of Scotland (2002-2006) and from New Brunswick, Canada (2004-2008). Life stages were categorized into two groups (adult females and the remaining mobile stages) to examine the trends in mean abundance and treatment effectiveness. Differences in emamectin benzoate effectiveness were found between the two groups by year and location, suggesting that an important part of monitoring drug resistance development in aquatic ectoparasites may be the need to focus on key life stages. © 2013 Blackwell Publishing Ltd.

Differential modulation of host genes in the kidney of brown trout Salmo trutta during sporogenesis of Tetracapsuloides bryosalmonae (Myxozoa).

Science.gov (United States)

Kumar, Gokhlesh; Abd-Elfattah, Ahmed; El-Matbouli, Mansour

2014-10-04

Tetracapsuloides bryosalmonae (Myxozoa) is the causative agent of proliferative kidney disease in various species of salmonids in Europe and North America. In Europe, spores of T. bryosalmonae develop in the kidney of infected brown trout Salmo trutta and are released via urine to infect the freshwater bryozoan Fredericella sultana. The transcriptomes of kidneys of infected and non-infected brown trout were compared by suppressive subtractive hybridization. Differential screening and a subsequent NCBI BLAST analysis of expressed sequence tags revealed 21 transcripts with functions that included cell stress and cell growth, ribonucleoprotein, signal transduction, ion transporter, immune response, hemoglobin and calcium metabolisms. Quantitative real time PCR was used to verify the presence of these selected transcripts in brown trout kidney at sporogonic stages of T. bryosalmonae development. Expression of cold-inducible RNA-binding protein, cyclin-dependent kinase inhibitor 2A, prothymosin alpha, transforming protein RhoA, immunoglobulin light chain and major histocompatibility complex class I were up-regulated significantly in infected brown trout. Expression of both the hemoglobin subunit beta and stanniocalcin precursor were down-regulated significantly in infected brown trout. This study suggests that cell stress and cell growth processes, signal transduction activities, erythropoiesis and calcium homeostasis of the host are modulated during sporogonic stages of parasite development, which may support the sporogenesis of T. bryosalmonae in the kidney of brown trout.

Associations between piscine reovirus infection and life history traits in wild-caught Atlantic salmon Salmo salar L. in Norway.

Science.gov (United States)

Garseth, Ase Helen; Biering, Eirik; Aunsmo, Arnfinn

2013-10-01

Piscine Reovirus (PRV), the putative causative agent of heart and skeletal muscle inflammation (HSMI), is widely distributed in both farmed and wild Atlantic salmon (Salmo salar L.) in Norway. While HSMI is a common and commercially important disease in farmed Atlantic salmon, the presence of PRV has so far not been associated with HSMI related lesions in wild salmon. Factors associated with PRV-infection were investigated in returning Atlantic salmon captured in Norwegian rivers. A multilevel mixed-effect logistic regression model confirmed clustering within rivers and demonstrated that PRV-infection is associated with life-history, sex, catch-year and body length as a proxy for sea-age. Escaped farmed salmon (odds ratio/OR: 7.32, p<0.001) and hatchery-reared salmon (OR: 1.69 p=0.073) have higher odds of being PRV-infected than wild Atlantic salmon. Male salmon have double odds of being PRV infected compared to female salmon (OR: 2.11, p<0.001). Odds of being PRV-infected increased with body-length measured as decimetres (OR: 1.20, p=0.004). Since body length and sea-age are correlated (r=0.85 p<0.001), body length serves as a proxy for sea-age, meaning that spending more years in sea increases the odds of being PRV-infected. Copyright © 2013 The Author. Published by Elsevier B.V. All rights reserved.

Effect of polyunsatured aldehyde (A3 as an antiparasitary ingredient of Caligus rogercresseyi in the feed of Atlantic salmon, Salmo salar Efecto del aldehído poli-insaturado (A3 como ingrediente antiparasitario de Caligus rogercresseyi en la alimentación de salmón del atlántico, Salmo salar

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José Troncoso

2011-11-01

Full Text Available Some polyunsaturated aldehydes (PUAs such as 2-trans, 4-trans decadenial (A3 have a detrimental effect on the development of copepod sharmful to the salmon industrysuch as Caligus rogercresseyi (sea lice. The purpose of this study was to evaluate the potential use of A3 as a salmon feed ingredient in order to reduce reproduction of Caligus rogercresseyi in infested Atlantic salmon (Salmo salar. The toxicity of A3 was assessed histopathologically for 7 days, using intra-peritoneal injections of different doses (0, 0.24, 0.47, 2.37, 11.86, and 23.71 mg kg-1 in brain, intestine, skin, liver, and muscletissues of Salmosalar at the end of each treatment. The effect of A3 on sea lice was evaluated using 250 Atlantic salmon in an open-flow system of seawater (~13°C. The effect of the dosage in the fish diet was evaluated at two levels (9 mg kg-1, 18 mg kg-1 and considering a control (without A3 for 4, 8, and 12 days, once the sea lice had reached maturity. As a complement, the persistent effect of diluted A3 in sea water (0.5 g L-1 was evaluated at 10, 12, and 14°C for 0, 1, 3, 6, 10, and 15 days; and the maximum persistence was found at 10 days at 10°C. The results showed that the dosages over 0.47 mg kg-1 had no toxic effect on Atlantic salmon, but induced a detrimental effect on Caligus rogercresseyi (reduction of 15% of mature females with a dose of 18 mg kg-1, which could be attributed to alterations in the embryonic development of the sea lice. A3 is a potential supplement in the diet of salmon. However, studies ofits mechanism of action should be undertaken prior to its use.Algunos aldehídos poli-insaturados (PUAs tales como 2-trans, 4-trans decadenal (A3 tienen efecto perjudicial para el desarrollo de copépodos perjudiciales para la industria del salmón, tales como Caligus rogercresseyi (piojo de mar. El objetivo del presente estudio fue evaluar el uso potencial de A3 en alimentación de salmones, de forma de reducir la reproducción de

Fish introductions in the former Soviet Union: The Sevan trout (Salmo ischchan - 80 years later.

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Wiesław Bogdanowicz

Full Text Available The Soviet Union played the leading role in fish introductions in Eurasia. However, only 3% of all introductions prior to 1978 gave a commercial benefit. One of the noteworthy examples appears to be the Sevan trout (Salmo ischchan Kessler, 1877-an endemic salmonid of Lake Sevan in Armenia. This species has been introduced to Kirghizstan, Kazakhstan, and Uzbekistan, however, only the Kirghiz population has persisted in relatively high numbers. In this paper we provide the first extensive molecular study of S. ischchan using samples from the native population from Lake Sevan and three hatcheries in Armenia, as well as from the population introduced to Lake Issyk Kul in Kirghizstan. The Kirghiz population has been isolated since the introductions took place in 1930 and 1936. Our results, based on 11 nuclear microsatellites and a 905 bp fragment of the mitochondrial control region suggest that hatcheries have maintained genetic variability by way of ongoing translocations of individuals from Lake Sevan. Simultaneously, significant Garza-Williamson M-values suggest that bottlenecks could have reduced the genetic variability of the wild populations in the past. This hypothesis is supported by historical data, indicating highly manipulated water-level regulations and poaching as two main factors that dramatically impact fish abundance in the lake. On the other hand, a similar situation has been observed in Kirghizstan, but this population likely rebounded from small population size faster than the other populations examined. The Kirghiz population is significantly genetically differentiated from the other groups and have morphological features and biological attributes not observed in the source population. Genetic data imply that the effective population size in the native population is lower than that found in the introduced population, suggesting that some active protection of the Lake Sevan population may be needed urgently.

Epithelial Label-Retaining Cells Are Absent during Tooth Cycling in Salmo salar and Polypterus senegalus.

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Sam Vandenplas

Full Text Available The Atlantic salmon (Salmo salar and African bichir (Polypterus senegalus are both actinopterygian fish species that continuously replace their teeth without the involvement of a successional dental lamina. Instead, they share the presence of a middle dental epithelium: an epithelial tier enclosed by inner and outer dental epithelium. It has been hypothesized that this tier could functionally substitute for a successional dental lamina and might be a potential niche to house epithelial stem cells involved in tooth cycling. Therefore, in this study we performed a BrdU pulse chase experiment on both species to (1 determine the localization and extent of proliferating cells in the dental epithelial layers, (2 describe cell dynamics and (3 investigate if label-retaining cells are present, suggestive for the putative presence of stem cells. Cells proliferate in the middle dental epithelium, outer dental epithelium and cervical loop at the lingual side of the dental organ to form a new tooth germ. Using long chase times, both in S. salar (eight weeks and P. senegalus (eight weeks and twelve weeks, we could not reveal the presence of label-retaining cells in the dental organ. Immunostaining of P. senegalus dental organs for the transcription factor Sox2, often used as a stem cell marker, labelled cells in the zone of outer dental epithelium which grades into the oral epithelium (ODE transition zone and the inner dental epithelium of a successor only. The location of Sox2 distribution does not provide evidence for epithelial stem cells in the dental organ and, more specifically, in the middle dental epithelium. Comparison of S. salar and P. senegalus reveals shared traits in tooth cycling and thus advances our understanding of the developmental mechanism that ensures lifelong replacement.

Regulation of the glucocorticoid receptor mRNA levels in the gills of Atlantic salmon (Salmo salar during smoltification

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MAZURAIS D.

1998-07-01

Full Text Available The regulation of the Glucocorticoid Receptor (GR transcript was investigated in the gills of Atlantic salmon (Salmo salar during the parr-smolt transformation. Sampling of parr and smolt fish was performed between December and July and in particular during the smoltification period occurring in spring. Quantification of GR transcripts revealed differences between the two groups in March and at the beginning of April. During these dates, the amounts of GR mRNA in parr gills were respectively three and two fold lower than those measured in smolts. In order to determine which factors are responsible for these differences, we studied the long-term effects of prolactin and Cortisol treatments on GR transcript in the gills of presmolt fish. The plasma levels of these two hormones respectively drop and rise during smoltification. Contrary to Cortisol long-term treatment which did not modify the amount of gill GR transcript, short-term treatment induced a significant decrease within 12 hours. Prolactin long-term treatment caused a significant increase of GR transcript abundance after 13 days of implant treatment. This result is unexpected with regard to those obtained in the smoltification analysis but is in agreement with previous studies performed in mammary gland revealing a positive control of PRL on GR in epithelial cells. Our data suggest that the regulation of the GR transcript during the parr-smolt transformation probably involves several hormonal factors.

Suppression of the primary immune response in rainbow trout, Salmo gairdneri, sublethally exposed to tritiated water during embryogenesis

International Nuclear Information System (INIS)

Strand, J.A.

1975-01-01

Antibody synthesis in response to vaccination with a 0.1 cc (1.8 x 10 8 cells/cc) intraperitoneally injected heat-killed strain of Flexibacter columnaris was employed to investigate the effect of tritium irradiation (0, 0.04, 0.4, 4.0 and 40.0 rads total dose for 20 days during embryogenesis) on development of the primary immune response in 5-month rainbow trout, Salmo gairdneri. Total serum protein measurements and electrophoretic separation of blood serum proteins followed by densitometric analyses were performed to assess the potential for qualitative and quantitative changes in blood serum components which conceivably accounted for suppressed immune responsiveness in tritium-irradiated fish. Data on the biological effects of tritium on early life stages in terms of hatchability, abnormality, latent mortality, and growth were also collected. A review of all experiments directed at determining the effects of early radiation exposure on the parameters of hatchability, incidence of abnormality, latent mortality and depressed growth, revealed considerable variation among similar treatments and indicated that significant effects at dose levels of 50 rads and below were not consistently demonstrated. While present experimental results demonstrated that the primary immune response in juvenile rainbow trout was significantly suppressed following embryonic exposure to tritium at essentially the 1.0 μCi/ml level, and perhaps at the 0.1 μCi/ml level, these concentrations are no less than 5 to 6 orders of magnitude above present levels for tritium in the aquatic environment

Browse Title Index

African Journals Online (AJOL)

Items 51 - 100 of 719 ... African Journal of Aquatic Science. ... Vol 32, No 2 (2007), Algal communities associated with aquatic macrophytes ... index to Clarias gariepinus (Teleostei: Clariidae) in the Vaal River system, South Africa, Abstract ... Vol 40, No 2 (2015), Benthic macroinvertebrate assemblages in mangroves and open ...

Factors determining parasite community richness and species composition in black snook Centropomus nigrescens (Centropomidae) from coastal lagoons in Guerrero, Mexico

Czech Academy of Sciences Publication Activity Database

Violante-González, J.; Mendoza-Franco, Edgar F.; Rojas-Herrera, A.; Guerrero, S.G.

2010-01-01

Roč. 107, č. 1 (2010), 59-66 ISSN 0932-0113 Institutional research plan: CEZ:AV0Z60220518 Keywords : TRES-PALOS LAGOON * HELMINTH COMMUNITIES * PACIFIC COAST * BALTIC SEA * FISHES * SIMILARITY * COLONIZATION * TELEOSTEI * BRAZIL * GILLS Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.812, year: 2010

Biochemical and Physiological Responses in Atlantic Salmon (Salmo salar) Following Dietary Exposure to Copper and Cadmium

International Nuclear Information System (INIS)

Lundebye, A.-K.; Berntssen, M.H.G.; Bonga, S.E.Wendelaar; Maage, A.

1999-01-01

Three experiments were conducted with Atlantic salmon (Salmo salar) to assess the effects of dietary exposure to copper and cadmium. The results presented here provide an overview, details of each experiment will be published in full elsewhere. In the first experiment, salmon parr exposed for four weeks to 35 and 700 mg Cu kg -1 diet had significantly elevated intestinal copper concentrations, cell proliferation (PCNA) and apoptosis rates compared to control fish. No differences were observed in gill or plasma copper concentrations among the groups. In contrast to the controls, the Cu exposed groups did not grow significantly during the exposure period. The second experiment (three months exposure) was conducted to assess the effects of dietary copper (control, 35, 500, 700, 900 or 1750 mg Cu kg -1 diet) on growth and feed utilization in salmon fingerlings. Growth was significantly reduced after three months exposure to dietary Cu concentrations above 500 mg kg -1 . Similarly, copper body burdens were significantly higher in fish exposed to elevated dietary copper concentrations (above 35 mg Cu kg -1 diet). In the third experiment, salmon parr were exposed to one of six dietary cadmium concentrations (0, 0.5, 5, 25, 125 or 250 mg Cd kg -1 diet) for four months. Cadmium accumulated in the liver>intestine>gills of exposed fish. Rates of apoptosis and cell proliferation in the intestine increased following exposure to dietary cadmium. Exposure to elevated concentrations of dietary cadmium had no effect on growth in salmon parr. Results from these studies indicate that cellular biomarkers have potential as early warning signs of negative effects on the overall fitness of an organism

Uptake of 17β-estradiol and biomarker responses in brown trout (Salmo trutta) exposed to pulses

International Nuclear Information System (INIS)

Knudsen, Jacob J.G.; Holbech, Henrik; Madsen, Steffen S.; Bjerregaard, Poul

2011-01-01

In streams, chemicals such as 17β-estradiol (E2) are likely to occur in pulses. We investigated uptake and biomarker responses in juvenile brown trout (Salmo trutta) of 3- or 6-h pulses of concentrations up to 370 ng E2 L -1 . Uptake by the fish was estimated from disappearance of E2 from tank water. A single 6-h pulse of 370 ng E2 L -1 increased the plasma vitellogenin concentration, liver Erα- and vitellogenin-mRNA. Exposure to 150-160 ng E2 L -1 for 6 h increased vitellogenin in one experiment but not in another. Two 6-h pulses had a larger effect one pulse. Brown trout in the size range 24-74 g took up E2 linearly with time and exposure concentration with a concentration ratio rate of 20.2 h -1 . In conclusion, the threshold for induction of estrogenic effects in juvenile brown trout at short term pulse exposure appears to be in the range 150-200 ng E2 L -1 . - Highlights: → We investigated estrogenic effects of pulse exposure of 17β-estradiol in brown trout. → We used induction of vitellogenin and gene expression as biomarkers. → The threshold for effects after 6 h pulses ranges between 150 and 200 ng E2 L -1 . → E2 is taken up in ∼50 g fish linearly with time and concentration at 20 h -1 . - The threshold concentration for induction of estrogenic effects in brown trout upon short term (6 h) exposure is in the range 150-200 ng E2 L -1 .

Uptake of 17{beta}-estradiol and biomarker responses in brown trout (Salmo trutta) exposed to pulses

Energy Technology Data Exchange (ETDEWEB)

Knudsen, Jacob J.G.; Holbech, Henrik; Madsen, Steffen S. [Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense (Denmark); Bjerregaard, Poul, E-mail: poul@biology.sdu.dk [Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense (Denmark)

2011-12-15

In streams, chemicals such as 17{beta}-estradiol (E2) are likely to occur in pulses. We investigated uptake and biomarker responses in juvenile brown trout (Salmo trutta) of 3- or 6-h pulses of concentrations up to 370 ng E2 L{sup -1}. Uptake by the fish was estimated from disappearance of E2 from tank water. A single 6-h pulse of 370 ng E2 L{sup -1} increased the plasma vitellogenin concentration, liver Er{alpha}- and vitellogenin-mRNA. Exposure to 150-160 ng E2 L{sup -1} for 6 h increased vitellogenin in one experiment but not in another. Two 6-h pulses had a larger effect one pulse. Brown trout in the size range 24-74 g took up E2 linearly with time and exposure concentration with a concentration ratio rate of 20.2 h{sup -1}. In conclusion, the threshold for induction of estrogenic effects in juvenile brown trout at short term pulse exposure appears to be in the range 150-200 ng E2 L{sup -1}. - Highlights: > We investigated estrogenic effects of pulse exposure of 17{beta}-estradiol in brown trout. > We used induction of vitellogenin and gene expression as biomarkers. > The threshold for effects after 6 h pulses ranges between 150 and 200 ng E2 L{sup -1}. > E2 is taken up in {approx}50 g fish linearly with time and concentration at 20 h{sup -1}. - The threshold concentration for induction of estrogenic effects in brown trout upon short term (6 h) exposure is in the range 150-200 ng E2 L{sup -1}.

Age- and stage-dependent variations of muscle-specific gene expression in brown trout Salmo trutta L.

Science.gov (United States)

Churova, Maria V; Meshcheryakova, Olga V; Ruchev, Mikhail; Nemova, Nina N

2017-09-01

This study was conducted to characterize the features of muscle-specific genes expression during development of brown trout Salmo trutta inhabiting the river Krivoy ruchey (Kola Peninsula, Russia). Gene expression levels of myogenic regulatory factors (MRFs - MyoD1 paralogs (MyoD1a, MyoD1b, MyoD1c), Myf5, myogenin), myostatin paralogs (MSTN-1a, MSTN-1b, MSTN-2a), fast skeletal myosin heavy chain (MyHC) were measured in the white muscles of brown trout parr of ages 0+ (under-yearling), 1+ (yearling) and 2+ (two year old) and smolts of age 2+. Multidirectional changes in MyoD1 and MSTN paralogs expression along with myogenin, Myf 5 and MyHC expression levels in white muscles in parr of trout with age were revealed. The expression of MyoD1c, myogenin, MSTN-2a was the highest in 0+ parr and then decreased. MyoD1a/b expression levels didn't differ between age groups. The simultaneous elevation of MyHC, Myf5, MSTN-1a, and MSTN-1b was found in trout yearlings. In smolts, expression levels of MSTN paralogs, MyHC, Myf5, MyoD1a was lower than in parr. But in contrast, the MyoD1c and myogenin mRNA levels was higher in smolts. The study revealed that there are definite patterns in simultaneous muscle-specific genes expression in age groups of parr and smolts. As MyoD and MSTN paralogs expression changed differently in dependence on age and stage, it was suggested that paralogs of the same gene complementarily control myogenesis during development. Copyright © 2017 Elsevier Inc. All rights reserved.

Skeletal muscle protease activities in the early growth and development of wild Atlantic salmon (Salmo salar L.).

Science.gov (United States)

Lysenko, Liudmila A; Kantserova, Nadezda P; Kaivarainen, Elena I; Krupnova, Marina Yu; Nemova, Nina N

2017-09-01

Growth-related dynamics of intracellular protease activities in four year classes of the Atlantic salmon (Salmo salar L. 1758) parr and smolts inhabiting salmon rivers of northwestern Russia (the White Sea basin) were studied. Cathepsin B, cathepsin D, proteasome, and calpain activities in the skeletal muscles of salmon were assessed to investigate their relative contribution to the total protein degradation as well as to young fish growth process. It was confirmed that calpain activity dominates in salmon muscles while proteasome plays a minor role, in contrast to terrestrial vertebrates. Calpain and proteasome activities were maximal at the early post-larval stage (in parrs 0+) and declined with age (parrs 1+ through 2+) dropping to the lowest level in salmon smolts. Annual growth increments and proteolytic activities of calpains and proteasome in the muscles of salmon juveniles changed with age in an orchestrated manner, while lysosomal cathepsin activities increased with age. Comparing protease activities and growth increments in salmon parr and smolts we suggested that the partial suppression of the protein degradation could be a mechanism stimulating efficient growth in smoltifying salmon. Growth and smoltification-related dynamics of protease activities was quite similar in salmon populations from studied spawning rivers, such as Varzuga and Indera; however, some habitat-related differences were observed. Growth increments and protease activities varied in salmon parr 0+ (but not on later ages) inhabiting either main rivers or small tributaries apparently due to habitat difference on the resources for fish growth. Copyright © 2017 Elsevier Inc. All rights reserved.

Assessing the sensitivity of Atlantic salmon (Salmo salar) to dietary endosulfan exposure using tissue biochemistry and histology

International Nuclear Information System (INIS)

Glover, Chris N.; Petri, Dietrich; Tollefsen, Knut-Erik; Jorum, Nanne; Handy, Richard D.; Berntssen, Marc H.G.

2007-01-01

The incorporation of plant-based ingredients, and the possible carry-over of pesticides such as endosulfan, in fish feeds may present new toxicological challenges to aquacultural species. Biological responses of Atlantic salmon (Salmo salar) to a 35-day dietary endosulfan exposure at levels ranging from 4 to 710 μg kg -1 were assessed using tissue histology and biochemistry. Liver 7-ethoxyresorufin-O-deacetylase (EROD) activity was significantly elevated in the highest exposure group (710 μg kg -1 ) by day 35. Other hepatic indicators of stress impacts and responses (glutathione-S-transferase and glutathione peroxidase activities and hepatic α-tocopherol content) remained unchanged. Branchial Na + , K + -ATPase activity was significantly reduced at day 14 in the highest exposure group, but returned to control levels by day 35. Conversely, intestinal Na + , K + -ATPase activity was significantly inhibited at day 35, but again only at the highest exposure level. In contrast to the biochemical results, hepatic and intestinal histology revealed effects of exposure even at the lowest dose tested (4 μg kg -1 ). In the posterior intestine, pathology was characterised by vacuolation and fusion of villi, and in the most severe cases, loss of epithelial integrity in villi tips. In the liver the primary effects were glycogen depletion and lipidosis. These changes were typical of a generalised stress response. While histology endpoints may prove to be the most sensitive indicators of dietary endosulfan exposure, the organismal relevance of these structural changes must be considered in the absence of effects in other biomarkers at dietary levels less than 710 μg kg -1

Comparison of sperm motility subpopulation structure among wild anadromous and farmed male Atlantic salmon (Salmo salar) parr using a CASA system.

Science.gov (United States)

Caldeira, Carina; García-Molina, Almudena; Valverde, Anthony; Bompart, Daznia; Hassane, Megan; Martin, Patrick; Soler, Carles

2018-04-13

Atlantic salmon (Salmo salar) is an endangered freshwater species that needs help to recover its wild stocks. However, the priority in aquaculture is to obtain successful fertilisation and genetic variability to secure the revival of the species. The aims of the present work were to study sperm subpopulation structure and motility patterns in wild anadromous males and farmed male Atlantic salmon parr. Salmon sperm samples were collected from wild anadromous salmon (WS) and two generations of farmed parr males. Sperm samples were collected from sexually mature males and sperm motility was analysed at different times after activation (5 and 35s). Differences among the three groups were analysed using statistical techniques based on Cluster analysis the Bayesian method. Atlantic salmon were found to have three sperm subpopulations, and the spermatozoa in ejaculates of mature farmed parr males had a higher velocity and larger size than those of WS males. This could be an adaptation to high sperm competition because salmonid species are naturally adapted to this process. Motility analysis enables us to identify sperm subpopulations, and it may be useful to correlate these sperm subpopulations with fertilisation ability to test whether faster-swimming spermatozoa have a higher probability of success.

Selective precipitation reaction: a novel diagnostic test for tissue pathology in Atlantic salmon, Salmo salar, infected with salmonid alphavirus (SAV3).

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Braceland, M; Tinsley, J; Cockerill, D; Bickerdike, R; McLoughlin, M F; Eckersall, P D

2017-08-01

While investigating biomarkers for infection with salmonid alphavirus (SAV), the cause of pancreas disease (PD), a selective precipitation reaction (SPR) has been discovered in serum which could be an on-farm qualitative test and an in-laboratory quantitative assay for health assessments in aquaculture. Mixing serum from Atlantic salmon, Salmo salar, with SAV infection with a sodium acetate buffer caused a visible precipitation which does not occur with serum from healthy salmon. Proteomic examination of the precipitate has revealed that the components are a mix of muscle proteins, for example enolase and aldolase, along with serum protein such as serotransferrin and complement C9. The assay has been optimized for molarity, pH, temperature and wavelength so that the precipitation can be measured as the change in optical density at 340 nm (Δ 340 ). Application of the SPR assay to serum samples from a cohabitation trial of SAV infection in salmon showed that the Δ 340 in infected fish rose from undetectable to a maximum at 6 weeks post-infection correlating with histopathological score of pancreas, heart and muscle damage. This test may have a valuable role to play in the diagnostic evaluation of stock health in salmon. © 2016 The Authors. Journal of Fish Diseases Published by John Wiley & Sons Ltd.

Method for aquatic multiple species toxicant testing: acute toxicity of 10 chemicals to 5 vertebrates and 2 invertebrates. [Pimephales promelas; Carassius auratus; Ictalurus punctatus; Lepomis macrochirus; Salmo gairdneri; Orconectes immunis; Aplexa hypnorum

Energy Technology Data Exchange (ETDEWEB)

Phipps, G.L.; Holcombe, G.W.

1985-01-01

A method was developed to simultaneously ascertain 96 h LC/sub 50/ values for seven freshwater species in a single flow through test with measured concentrations. It allows interspecific comparisons, easy determination of the most sensitive species, and cuts cost of labor, materials and chemical analysis for measured concentration tests. Species tested included fathead minnows Pimephales promelas, goldfish Carassius auratus, channel catfish Ictalurus punctatus, bluegill Lepomis macrochirus, rainbow trout Salmo gairdneri, crayfish Orconectes immunis and snails Aplexa hypnorum. Compounds tested were pentachlorophenol, 2-chloroethanol, 2,4-pentanedione, hexachloroethane, ..cap alpha..-bromo-2',5'-dimethoxyacetophenone, benzaldehyde, 1,3-dichloro-4,6-dinitro-benzene, dursban, sevin and cadmium chloride. The LC/sub 50/ values from these multiple species tests compared favourably with those determined using single species tests at this laboratory, usually within 20%.

Efficacy of emamectin benzoate against sea lice infestations of Atlantic salmon, Salmo salar L.: evaluation in the absence of an untreated contemporary control.

Science.gov (United States)

Gustafson, L; Ellis, S; Robinson, T; Marenghi, F; Endris, R

2006-10-01

The efficacy of emamectin benzoate (SLICE) against sea lice infestations of Atlantic salmon, Salmo salar L., is typically assessed using untreated fish, or fish treated with alternative therapeutants, as controls. The State of Maine, USA, is currently under active management for the OIE-notifiable pathogen, infectious salmon anaemia virus (ISAV); consequently, neither control group is feasible in this region. Untreated salmon risk extensive damage from the ectoparasites, and threaten to increase vector-borne exposure or susceptibility of farms to ISAV; and the only treatment presently available in Maine is SLICE. However, because sea lice infestations are unlikely to resolve spontaneously, and response to treatment occurs within weeks, use of a pretreatment baseline is a reasonable alternative for confirmatory studies. We evaluated SLICE efficacy on Atlantic salmon farms in Cobscook Bay 2002-2005, in the absence of untreated controls, using pretreatment lice loads as a reference for calculation. Maximum efficacy ranged from 68% to 100% reduction from initial levels. Time-to-maximum efficacy ranged from 1 to 8 weeks after treatment initiation. Efficacy duration, measured between first reduction and first progressive rise in counts, ranged from 4 to 16 weeks.

TUCUNARELLA N. GEN. AND OTHER DACTYLOGYRIDS (MONOGENOIDEA) FROM CICHLID FISH (PERCIFORMES) FROM PERUVIAN AMAZONIA

Czech Academy of Sciences Publication Activity Database

Mendoza-Franco, Edgar F.; Scholz, Tomáš; Rozkošná, Petra

2010-01-01

Roč. 96, č. 3 (2010), s. 491-498 ISSN 0022-3395 R&D Projects: GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : NEOTROPICAL MONOGENEA * ANCYROCEPHALINAE * PROPOSAL * GILLS * TREMATODES * TELEOSTEI Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.208, year: 2010

Tentative de réacclimatation de Salmo salar dans le bassin de la Bresle (Normandie, France

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ARRIGNON J.

2008-09-01

Full Text Available La BRESLE, rivière séparant la Haute-Normandie de la Picardie, dans le Nord-Ouest de la France était occasionnellement fréquentée jusqu'en 1964 par le saumon de lAtlantique, Salmo Salar. Le Conseil Supérieur de la Pêche a décidé de diriger l'essentiel des moyens consacrés à cette région à la réacclimatation du saumon, à l'« ensaumonnement » de ce cours d'eau. Le choix a été opéré en fonction de la situation hydrographique, hydraulique et hydrobiologique de la rivière. Les travaux ont porté sur la lutte contre la pollution sévissant dans la basse vallée, la lutte contre le braconnage, l'amélioration du milieu aquatique : franchissement d'obstacles à la remontée des salmonidés migrateurs, ameublissement des frayères, enlèvement des prédateurs. Ils ont également porté sur des introductions annuelles d'environ 100.000 oeufs de saumons à des stades divers. Les résultats montrent que le nombre des smolts s'accroît, de même que, en 1972, le nombre des adultes contrôlés et marqués lors de leurs déplacements. Le nombre modeste des uns et des autres ainsi que le caractère récent de cette réapparition du saumon en Bresle ne permettent pas de dire qu'il y a réacclimatation de l'espèce : il s'agit d'un simple indice favorable à la réacclimatation du saumon. L'auteur conclut en pensant que la truite de mer présente dans les cours d'eau de cette région un intérêt supérieur à celui du Saumon mais que, dans le cas particulier de la rivière la BRESLE, l'introduction du saumon est une initiative intéressante pour les pêcheurs sportifs. Il conviendra toutefois de grossir considérablement l'ensaumonnement en introduisant davantage de smolts. Il sera également important de prévoir une réglementation de la pêche assurant le maintien de l'installation du saumon dans cette rivière. The Bresle river, running between upper Normandy and Picardy in the North-Western part of France, saw occasional runs of

La croissance de la truite commune (Salmo trutta L. sur le bassin de Scorff

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BAGLINIÈRE J. L.

1990-07-01

Full Text Available La croissance de la truite commune (Salmo trutta L. a été étudiée à partir du suivi de cinq cohortes âgées de 0 - à 2 - ans dans quatre milieux différents (Scorff aval et amont, affluent, sous-affluent. D'une manière générale, la taille destruites quelque soit leur âge diminue de l'aval vers l'amont du Scorff et de la rivière à l'affluent et au sous-affluent. Le taux mensuel de croissance G = 2,85 (LnL2 — LnL1/(T2 — T1 diminue de la première à la troisième année de vie quelque soit l'ordre de drainage. Ce taux de croissance varie suivant le milieu pour les deux premières classes d'âge (0 + et 1 +, cet effet milieu étant relié à la densité de population pour les individus 0 +. Le taux de croissance varie également suivant les années mais uniquement chez les plus jeunes truites et cet effet année est relié principalement à la température de l'eau. Un modèle de Von Bertalanffy est proposé pour décrire la relation entre la taille (Lf et la somme des températures moyennes journalières depuis la date moyenne d'émergence (Tmjpendant la première année : Lf = 106,7 (1 — exp [ — 0,0005 (Tmj + 468]. Les résultats sont discutés et permettent de dégager les faits majeurs intervenant sur la croissance de la truite tout au long d'un cycle jusqu'à la maturation sexuelle. Mots-clés : Température - Croissance - Truite commune - Rivière - France.

Evidence for long-term change in length, mass and migration phenology of anadromous spawners in French Atlantic salmon Salmo salar.

Science.gov (United States)

Bal, G; Montorio, L; Rivot, E; Prévost, E; Baglinière, J-L; Nevoux, M

2017-06-01

This study provides new data on Atlantic salmon Salmo salar life-history traits across France. Using a long-term recreational angling database (1987-2013) covering 34 rivers in three regions (genetic units), a decline in individual length, mass and a delayed adult return to French rivers was reported. Temporal similarities in trait variations between regions may be attributed to common change in environmental conditions at sea. The relative rate of change in phenotypic traits was more pronounced in early maturing fish [1 sea-winter (1SW) fish] than in late maturing fish (2SW fish). Such contrasted response within populations highlights the need to account for the diversity in life histories when exploring mechanisms of phenotypic change in S. salar. Such detailed life-history data on returning S. salar have not previously been reported from France. This study on French populations also contributes to reducing the gap in knowledge by providing further empirical evidence of a global pattern in S. salar across its distribution range. Results are consistent with the hypothesis that the observed changes in life-history traits are primarily associated with environmental changes in the North Atlantic Ocean. They also emphasize the presence of less important, but still significant contrasts between region and life history. © 2017 The Fisheries Society of the British Isles.

Assessing the potential for rainbow trout reproduction in tributaries of the Mountain Fork River below Broken Bow Dam, southeastern Oklahoma

Science.gov (United States)

Long, James M.; Starks, Trevor A.; Farling, Tyler; Bastarache, Robert

2016-01-01

Stocked trout (Salmonidae) in reservoir tailwater systems in the Southern United States have been shown to use tributary streams for spawning and rearing. The lower Mountain Fork of the Little River below Broken Bow Dam is one of two year-round tailwater trout fisheries in Oklahoma, and the only one with evidence of reproduction by stocked rainbow trout (Oncorhynchus mykiss). Whether stocked trout use tributaries in this system for spawning is unknown. Furthermore, an

A salmonid EST genomic study: genes, duplications, phylogeny and microarrays

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Brahmbhatt Sonal

2008-11-01

Full Text Available Abstract Background Salmonids are of interest because of their relatively recent genome duplication, and their extensive use in wild fisheries and aquaculture. A comprehensive gene list and a comparison of genes in some of the different species provide valuable genomic information for one of the most widely studied groups of fish. Results 298,304 expressed sequence tags (ESTs from Atlantic salmon (69% of the total, 11,664 chinook, 10,813 sockeye, 10,051 brook trout, 10,975 grayling, 8,630 lake whitefish, and 3,624 northern pike ESTs were obtained in this study and have been deposited into the public databases. Contigs were built and putative full-length Atlantic salmon clones have been identified. A database containing ESTs, assemblies, consensus sequences, open reading frames, gene predictions and putative annotation is available. The overall similarity between Atlantic salmon ESTs and those of rainbow trout, chinook, sockeye, brook trout, grayling, lake whitefish, northern pike and rainbow smelt is 93.4, 94.2, 94.6, 94.4, 92.5, 91.7, 89.6, and 86.2% respectively. An analysis of 78 transcript sets show Salmo as a sister group to Oncorhynchus and Salvelinus within Salmoninae, and Thymallinae as a sister group to Salmoninae and Coregoninae within Salmonidae. Extensive gene duplication is consistent with a genome duplication in the common ancestor of salmonids. Using all of the available EST data, a new expanded salmonid cDNA microarray of 32,000 features was created. Cross-species hybridizations to this cDNA microarray indicate that this resource will be useful for studies of all 68 salmonid species. Conclusion An extensive collection and analysis of salmonid RNA putative transcripts indicate that Pacific salmon, Atlantic salmon and charr are 94–96% similar while the more distant whitefish, grayling, pike and smelt are 93, 92, 89 and 86% similar to salmon. The salmonid transcriptome reveals a complex history of gene duplication that is

Immunological cross-reactivity between four distant parvalbumins-Impact on allergen detection and diagnostics.

Science.gov (United States)

Sharp, Michael F; Stephen, Juan N; Kraft, Lukas; Weiss, Thomas; Kamath, Sandip D; Lopata, Andreas L

2015-02-01

Fish are the largest and most diverse group of vertebrates. Fish are also a part of the eight food groups that cause the majority of IgE mediated food reactions. Detection tools for fish allergens are however limited due to the great diversity of fish species, despite fish allergy and its major allergen parvalbumin being well documented. The most commonly studied fish are frequently consumed in North America and Europe. However, much less is known about fish allergens in the Australasian region although fish is widely consumed in this region. A comprehensive phylogenetic analysis was performed of known parvalbumin amino acid sequences to determine possible candidate antigens for new cross-reactive antibodies to be used to detect most fish parvalbumins. Polyclonal rabbit antibodies were raised against parvalbumins from frequently consumed barramundi (Lates calcarifer), basa (Pangasius bocourti), pilchard (Sardinops sagax) and Atlantic salmon (Salmo salar). These were evaluated for cross-reactivity against a panel of 45 fish extracts (raw, heated and canned fish). Anti-barramundi parvalbumin proved to be the most cross-reactive antibody, detecting 87.5% of the 40 species analyzed, followed by anti-pilchard and anti-basa antibody. In contrast the anti-salmon antibody was very specific and only reacted to salmonidae and a few other fish. All analyzed fish species, except mahi mahi, swordfish, yellowfin tuna and all 5 canned fish had parvalbumin detected in raw extracts. However antibody reactivity to many fish was heat liable or susceptible to denaturation, demonstrating that some parvalbumins have most likely conformational epitopes, which lose antibody reactivity after heat treatment. We have demonstrated the generation of highly cross-reactive anti-parvalbumin antibodies that could be used for the detection of allergenic fish parvalbumin in contaminated food products. This cross-reactivity study thus shows processing of fish, especially canning, can have on impact

Fish remains from Miocene beds of Višnja vas near Vojnik, Slovenia

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Aleš Šoster

2013-06-01

Full Text Available This paper discusses fossil teeth of sharks (Elasmobranchii, Neoselachii and porgies (Teleostei, Sparidae fromthe Miocene glauconite sandstones of Vi{nja vas near Vojnik. The remains of fish teeth, mostly tooth crowns, belongto cartilaginous fishes of the genera Notorynchus, Carcharias, Carcharoides, Isurus and Cosmopolitodus and to abony fish genus Pagrus.

African Zoology - Vol 17, No 1 (1982)

African Journals Online (AJOL)

The biology and taxonomic status of an estuarine population of Pranesus pinguis (Lacépède) (Teleostei: Atherinidae) in south east Africa · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. M.A.J. Harman, S.J.M. Blaber, D.P. Cyrus, 15-23 ...

An update on the fish composition (Teleostei of the coastal lagoons of the Restinga de Jurubatiba National Park and the Imboassica Lagoon, northern Rio de Janeiro State

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Fabio Di Dario

Full Text Available AIM: We present an update on the composition of the fish species of the Restinga de Jurubatiba National Park and the Imboassica Lagoon, in the northern portion of Rio de Janeiro State, based on collecting efforts of almost two decades, historical museum records, and a review of the literature. METHODS: Specimens were collected using a variety of techniques, mostly between 1994 and 2012, and were fixed with the use of a 10% solution of formalin and subsequently stored in 70% alcohol solution. All specimens examined are deposited in the fish collections of the Núcleo em Ecologia e Desenvolvimento Socioambiental de Macaé, Universidade Federal do Rio de Janeiro (NPM, and Museu Nacional, Universidade Federal do Rio de Janeiro (MNRJ. Continental (freshwater fishes and some marine or estuarine species frequently collected were regarded as Resident, whereas marine species collected only sporadically were regarded as Occasional. Possible associations between the orientation of the lagoons and the composition of Resident fishes were explored through a Correspondence Analysis (CA. RESULTS: A total of 100 species, belonging to 19 orders and 41 families of the Teleostei were recorded. When both Resident and Occasional species are considered, families Carangidae and Engraulidae, with nine and eight species respectively, are the most representative. When only Resident species are considered, the Gerreidae and Gobiidae, both with seven species, are the most representative families. The Imboassica Lagoon, with 76 species, has the highest species richness among lagoons included in this study. A total of 81 species were recorded in the Restinga de Jurubatiba National Park, a number two times higher than reported on previous studies. An identification key, including 57 Resident species, is also presented. CONCLUSIONS: Parallel lagoons were characterized by a small group of continental species presumably of marine ancestry (Secondary Division, while marine species

Development of intestinal ion-transporting mechanisms during smoltification and seawater acclimation in Atlantic salmon Salmo salar

Science.gov (United States)

Sundh, Henrik; Nilsen, Tom O.; Lindström, Jenny; Hasselberg-Frank, Linda; Stefansson, Sigurd O.; McCormick, Stephen D.; Sundell, K.

2014-01-01

This study investigated the expression of ion transporters involved in intestinal fluid absorption and presents evidence for developmental changes in abundance and tissue distribution of these transporters during smoltification and seawater (SW) acclimation of Atlantic salmonSalmo salar. Emphasis was placed on Na+, K+-ATPase (NKA) and Na+, K+, Cl− co-transporter (NKCC) isoforms, at both transcriptional and protein levels, together with transcription of chloride channel genes. The nka α1c was the dominant isoform at the transcript level in both proximal and distal intestines; also, it was the most abundant isoform expressed in the basolateral membrane of enterocytes in the proximal intestine. This isoform was also abundantly expressed in the distal intestine in the lower part of the mucosal folds. The protein expression of intestinal Nkaα1c increased during smoltification. Immunostaining was localized to the basal membrane of the enterocytes in freshwater (FW) fish, and re-distributed to a lateral position after SW entry. Two other Nka isoforms, α1a and α1b, were expressed in the intestine but were not regulated to the same extent during smoltification and subsequent SW transfer. Their localization in the intestinal wall indicates a house-keeping function in excitatory tissues. The absorptive form of the NKCC-like isoform (sub-apically located NKCC2 and/or Na+, Cl−co-transporter) increased during smoltification and further after SW transfer. The cellular distribution changed from a diffuse expression in the sub-apical regions during smoltification to clustering of the transporters closer to the apical membrane after entry to SW. Furthermore, transcript abundance indicates that the mechanisms necessary for exit of chloride ions across the basolateral membrane and into the lateral intercellular space are present in the form of one or more of three different chloride channels: cystic fibrosis transmembrane conductance regulator I and II and chloride channel

Measurement of peroxisomal enzyme activities in the liver of brown trout (Salmo trutta, using spectrophotometric methods

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Resende Albina D

2003-03-01

Full Text Available Abstract Background This study was aimed primarily at testing in the liver of brown trout (Salmo trutta spectrophotometric methods previously used to measure the activities of catalase and hydrogen peroxide producing oxidases in mammals. To evaluate the influence of temperature on the activities of those peroxisomal enzymes was the second objective. A third goal of this work was the study of enzyme distribution in crude cell fractions of brown trout liver. Results The assays revealed a linear increase in the activity of all peroxisomal enzymes as the temperature rose from 10° to 37°C. However, while the activities of hydrogen peroxide producing oxidases were strongly influenced by temperature, catalase activity was only slightly affected. A crude fraction enriched with peroxisomes was obtained by differential centrifugation of liver homogenates, and the contamination by other organelles was evaluated by the activities of marker enzymes for mitochondria (succinate dehydrogenase, lysosomes (aryl sulphatase and microsomes (NADPH cytochrome c reductase. For peroxisomal enzymes, the activities per mg of protein (specific activity in liver homogenates were strongly correlated with the activities per g of liver and with the total activities per liver. These correlations were not obtained with crude peroxisomal fractions. Conclusions The spectrophotometric protocols originally used to quantify the activity of mammalian peroxisomal enzymes can be successfully applied to the study of those enzymes in brown trout. Because the activity of all studied peroxisomal enzymes rose in a linear mode with temperature, their activities can be correctly measured between 10° and 37°C. Probably due to contamination by other organelles and losses of soluble matrix enzymes during homogenisation, enzyme activities in crude peroxisomal fractions do not correlate with the activities in liver homogenates. Thus, total homogenates will be used in future seasonal and

Differential response of continental stock complexes of Atlantic salmon (Salmo salar) to the Atlantic Multidecadal Oscillation

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Friedland, Kevin D.; Shank, Burton V.; Todd, Christopher D.; McGinnity, Philip; Nye, Janet A.

2014-05-01

Atlantic salmon, Salmo salar, in the North Atlantic are managed as a set of population complexes distributed in North America and Europe. In recent years, these complexes have experienced reduced marine survival and many populations within the complexes are at risk, especially those at the southern ends of the species amphi-Atlantic range. Atlantic salmon is an anadromous fish dividing its life history between residence in freshwater and the marine environment. The freshwater portion of the life history includes spawning and the rearing of juveniles where in-river production has tended to be relatively stable, whereas the first year at sea, termed the post-smolt year, is characterized by more variable rates of mortality. Although their habitats are widely separated geographically along the North Atlantic seaboards, strong recruitment coherence exists between North American and European stock complexes. This recruitment coherence is correlated with ocean temperature variation associated with the Atlantic Multidecadal Oscillation (AMO). The North Atlantic Oscillation (NAO) appears to be relatively unimportant as a driver of salmon abundance. The mechanism determining the link between AMO-related thermal variation and abundance appears to differ fundamentally for the two continental stock groupings. Whereas ocean climate variability during the first springtime months of juvenile salmon migration to sea appears to be important to the survival of North American stocks, summer climate variation appears to be central to adult recruitment variation for European stocks. This contrast in seasonal effects appears to be related to the varying roles of predation pressure and size-related mortality on the continental stock complexes. The anticipated warming due to global climate change will impose thermal conditions on salmon populations outside historical context and challenge the ability of many populations to persist.

Estrogen therapy offsets thermal impairment of vitellogenesis, but not zonagenesis, in maiden spawning female Atlantic salmon (Salmo salar

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Kelli Anderson

2017-11-01

Full Text Available In female Atlantic salmon (Salmo salar, exposure to warm summer temperatures causes a reduction in plasma 17β-estradiol (E2, which impairs downstream vitellogenesis and zonagenesis, and reduces egg fertility and embryo survival. The aim of the present study was to determine whether E2-treatment could offset thermal impairment of endocrine function and maintain egg quality in maiden (first-time-spawning S. salar reared at 22 °C. Treatment with E2 at 22 °C stimulated vitellogenin (vtg gene expression and subsequent protein synthesis which promoted oocyte growth and increased egg size relative to untreated fish at 14 and 22 °C. However, E2-treatment at 22 °C was not associated with an increase in egg fertility and embryo survival relative to untreated fish at 22 °C, despite the positive effects of E2-treatment on vitellogenesis and oocyte growth. As there was no evidence to suggest that the estrogen receptor alpha expression was suppressed by high temperature, this could be due to the lack of stimulation on zonagenesis by E2-treatment observed at high temperature during oocyte development. Our results demonstrate that treatment with E2 is not able to maintain zonagenesis or egg quality in maiden S. salar at high temperature, even when vtg gene expression, protein synthesis and subsequent oocyte growth is promoted. This implies that the mechanisms regulating zonagenesis, but not vitellogenesis are impaired at elevated temperature in female S. salar broodstock, and highlights the remarkable complexity of thermally induced endocrine disruption in fish.

Contaminant levels in Norwegian farmed Atlantic salmon (Salmo salar) in the 13-year period from 1999 to 2011.

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Nøstbakken, Ole Jakob; Hove, Helge T; Duinker, Arne; Lundebye, Anne-Katrine; Berntssen, Marc H G; Hannisdal, Rita; Lunestad, Bjørn Tore; Maage, Amund; Madsen, Lise; Torstensen, Bente E; Julshamn, Kåre

2015-01-01

Environmental pollutants such as dioxins and PCBs, heavy metals, and organochlorine pesticides are a global threat to food safety. In particular, the aquatic biota can bioaccumulate many of these contaminants potentially making seafood of concern for chronic exposure to humans. The main objective was to evaluate trends of contaminant levels in Norwegian farmed Atlantic salmon in light of the derived tolerable intakes. Through an EU-instigated surveillance programme, the Norwegian Food Safety Authority (NFSA) has between 1999 and 2011 collected more than 2300 samples of Norwegian farmed Atlantic salmon (Salmo salar) for contaminant analyses. The fillets of these fish were homogenised and analysed for dioxins, PCBs, heavy metals and organochlorine pesticides. The levels of the contaminants mercury, arsenic, dioxins, dioxin-like PCBs and DDT in Norwegian farmed salmon fillet have decreased during our period of analyses. The levels of cadmium, lead and several organochlorine pesticides were too close to the limit of quantification to calculate time trends. For PCB6 and quantifiable amounts of pesticides, except DDT, stable levels were observed. The contaminant levels in Norwegian farmed salmon have generally decreased between 1999 and 2011. Excluding other dietary sources, the levels of dioxins and dioxin-like PCBs in 2011 allowed consumption of up to 1.3kg salmon per week to reach the tolerable weekly intake. The group of contaminants which was the limiting factor for safe consumption of Norwegian farmed salmon, based on currently established TWI values, is the sum of dioxins and dioxin-like PCBs. Copyright © 2014. Published by Elsevier Ltd.

Etude de la structure d'une population de truite commune (Salmo trutta L. dans une zone à barbeau

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BAGLINIERE J. L.

1981-10-01

Full Text Available Au total 16 espèces de poissons, dont la truite commune (Salmo trutta L. ont été recensées par pêche électrique dans le cours aval de la rivière Colmont, classée rivière à salmonidés dominants, et un de ses affluents. La présence de gros cyprins d'eaux vives (barbeau, Barbus barbus L., et chevaine, Leuciscus cephalus L. et de quelques espèces de cyprins d'eaux lentes est une caractéristique de la zone à barbeau. Parmi les cyprins, les espèces les plus abondantes sont le goujon (Gobio gobio L. et le chevaine présent dans tous les types d'habitats de la rivière. La population de truites se caractérise par : — une faible densité dans la rivière et l'affluent et par une bonne croissance. Ces deux paramètres montrent des variations annuelles. — une ségrégation spatiale des classes d'âge ; les truites 0+ sont localisées principalement dans l'affluent, alors que dans la rivière les truites sont âgées d'au moins 1 an et sont présentes uniquement dans les zones rapide-radier. Les caractéristiques de cette population de truite sont discutées en considérant l'interaction possible avec les autres populations pisciaires dans un milieu dont l'habitat est dégradé.

Pharmacokinetics and transcriptional effects of the anti-salmon lice drug emamectin benzoate in Atlantic salmon (Salmo salar L.).

Science.gov (United States)

Olsvik, Pål A; Lie, Kai K; Mykkeltvedt, Eva; Samuelsen, Ole B; Petersen, Kjell; Stavrum, Anne-Kristin; Lunestad, Bjørn T

2008-09-11

Emamectin benzoate (EB) is a dominating pharmaceutical drug used for the treatment and control of infections by sea lice (Lepeophtheirus salmonis) on Atlantic salmon (Salmo salar L). Fish with an initial mean weight of 132 g were experimentally medicated by a standard seven-day EB treatment, and the concentrations of drug in liver, muscle and skin were examined. To investigate how EB affects Atlantic salmon transcription in liver, tissues were assessed by microarray and qPCR at 7, 14 and 35 days after the initiation of medication. The pharmacokinetic examination revealed highest EB concentrations in all three tissues at day 14, seven days after the end of the medication period. Only modest effects were seen on the transcriptional levels in liver, with small fold-change alterations in transcription throughout the experimental period. Gene set enrichment analysis (GSEA) indicated that EB treatment induced oxidative stress at day 7 and inflammation at day 14. The qPCR examinations showed that medication by EB significantly increased the transcription of both HSP70 and glutathione-S-transferase (GST) in liver during a period of 35 days, compared to un-treated fish, possibly via activation of enzymes involved in phase II conjugation of metabolism in the liver. This study has shown that a standard seven-day EB treatment has only a modest effect on the transcription of genes in liver of Atlantic salmon. Based on GSEA, the medication seems to have produced a temporary oxidative stress response that might have affected protein stability and folding, followed by a secondary inflammatory response.

INTRACELLULAR ION CONCENTRATIONS IN BRANCHIAL EPITHELIAL CELLS OF BROWN TROUT (SALMO TRUTTA L.) DETERMINED BY X-RAY MICROANALYSIS

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Morgan; Potts; Oates

1994-09-01

The intracellular concentrations of sodium, chloride, phosphorus and potassium under normal conditions in pavement epithelial (PE) cells of brown trout (Salmo trutta) gill were 66, 51, 87 and 88 mmol l-1 respectively. The concentrations of these elements under identical conditions in mitochondria-rich (MR) cells were not significantly different, except for that of chlorine, which was lower in MR cells (40 mmol l-1). The concentration of sodium in the PE cells decreased slightly after exposure of the fish to low external [Na+] (25 µmol l-1) for 7 days but increased greatly within 5 min of subsequent exposure to 1 mmol l-1 external Na+. These changes in external [Na+] had no significant effect on MR cells. Exposure of fish to low [Cl-] (25 µmol l-1) had no effect on PE or MR cells, but on exposure to 1 mmol l-1 Cl- the concentrations of chlorine, phosphorus and potassium in both types of cells increased, whilst the intracellular sodium concentration decreased only in MR cells. The PE cells were little affected by exposure of the fish to the carbonic anhydrase inhibitor acetazolamide. In contrast, 0.5 mmol l-1 external acetazolamide caused a significant decrease in intracellular phosphorus, chlorine and potassium concentrations in MR cells. This suggests that the PE cells are the sites of sodium uptake in the gills of the brown trout and that chloride uptake occurs via the MR cells. These results are discussed with respect to the sites and possible mechanisms of ionic exchange in freshwater vertebrates.

Metabolism, health and fillet nutritional quality in Atlantic salmon (Salmo salar) fed diets containing n-3-rich microalgae.

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Kousoulaki, Katerina; Østbye, Tone-Kari Knutsdatter; Krasnov, Aleksei; Torgersen, Jacob Seilø; Mørkøre, Turid; Sweetman, John

2015-01-01

Microalgae, as primary producers of EPA and DHA, are among the most prominent alternative sources to fish oil for n-3 long-chain PUFA in animal and human nutrition. The present study aimed to assess technical, nutritional and fish health aspects of producing n-3-rich Atlantic salmon (Salmo salar) fish fillets by dietary supplementation of increasing levels of a DHA-producing Schizochytrium sp. and reduced or without use of supplemental fish oil. Atlantic salmon smolt were fed diets with graded levels of microalgae for 12 weeks, during which all fish showed high feed intake rates with postprandial plasma leptin levels inversely correlating with final mean fish body weights. Fish performance was optimal in all experimental treatments (thermal growth coefficient about 4·0 and feed conversion ratio 0·8-0·9), protein digestibility was equal in all diets, whereas dietary lipid digestibility inversely correlated with the dietary levels of the SFA 16 : 0. Fillet quality was good and similar to the control in all treatments in terms of n-3 long-chain PUFA content, gaping, texture and liquid losses during thawing. Histological fluorescence staining and immunofluorescence analysis of salmon intestines (midgut: base of intestine and villi) revealed significant effects on slime, goblet cell production and inducible nitric oxide synthase (iNOS) activity with increasing levels of dietary Schizochytrium sp. supplementation. Microarray analysis did not reveal any signs of toxicity, stress, inflammation or any other negative effects from Schizochytrium sp. supplementation in diets for Atlantic salmon.

Delousing efficiency of farmed ballan wrasse (Labrus bergylta) against Lepeophtheirus salmonis infecting Atlantic salmon (Salmo salar) post-smolts.

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Leclercq, Eric; Davie, Andrew; Migaud, Hervé

2014-08-01

Cleaner-fish (wrasse, Labridae) are increasingly deployed within the Atlantic salmon (Salmo salar L.) industry as a biological control against sea-lice (Lepeophtheirus salmonis Krøyer). Two tank-based trials were performed to test the effect of farmed ballan wrasse (Labrus bergylta Ascanius) body mass and supplementary feeding on the delousing of Atlantic salmon post-smolts with an initial infection level of ∼12 lice salmon(-1) and a ∼5% wrasse:salmon ratio. Sea-louse levels below 0.5 lice salmon(-1) were obtained within 84 h, and preferential preying upon larger motile stages was found. The wrasse body mass and the availability of fresh, opened blue mussels (Mytilus edulis L.) did not significantly affect delousing efficiency. The functional predator response was linear, showing no minimum prey density threshold for sea-louse foraging and no satiation plateau, in spite of the high consumption rates measured. Sea-louse infection levels declined following a one-phase exponential decay model, with a standardised decline time constant of 0.8-1.3% h(-1) for each wrasse stocked per 100 salmon. Farmed ballan wrasse are confirmed as highly effective therapeutic and preventive biological controls against sea-lice. The study supports the current minimum hatchery size target (10 mm total length) and the use of supplementary feeding to sustain the wrasse stocks in operation. The functional predator response and the standardised decline time constant of sea-louse abundance are proposed as useful indicators of delousing efficiency. © 2013 Society of Chemical Industry.

Assessing the sensitivity of Atlantic salmon (Salmo salar) to dietary endosulfan exposure using tissue biochemistry and histology

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Glover, Chris N.; Petri, Dietrich [National Institute of Nutrition and Seafood Research (NIFES), Bergen (Norway); Tollefsen, Knut-Erik [Norwegian Institute for Water Research (NIVA), Oslo (Norway); Jorum, Nanne [Skretting ARC, Stavanger (Norway); Handy, Richard D. [School of Biological Sciences, University of Plymouth, Plymouth (United Kingdom); Berntssen, Marc H.G. [National Institute of Nutrition and Seafood Research (NIFES), Bergen (Norway)], E-mail: marc.berntssen@nifes.no

2007-10-15

The incorporation of plant-based ingredients, and the possible carry-over of pesticides such as endosulfan, in fish feeds may present new toxicological challenges to aquacultural species. Biological responses of Atlantic salmon (Salmo salar) to a 35-day dietary endosulfan exposure at levels ranging from 4 to 710 {mu}g kg{sup -1} were assessed using tissue histology and biochemistry. Liver 7-ethoxyresorufin-O-deacetylase (EROD) activity was significantly elevated in the highest exposure group (710 {mu}g kg{sup -1}) by day 35. Other hepatic indicators of stress impacts and responses (glutathione-S-transferase and glutathione peroxidase activities and hepatic {alpha}-tocopherol content) remained unchanged. Branchial Na{sup +}, K{sup +}-ATPase activity was significantly reduced at day 14 in the highest exposure group, but returned to control levels by day 35. Conversely, intestinal Na{sup +}, K{sup +}-ATPase activity was significantly inhibited at day 35, but again only at the highest exposure level. In contrast to the biochemical results, hepatic and intestinal histology revealed effects of exposure even at the lowest dose tested (4 {mu}g kg{sup -1}). In the posterior intestine, pathology was characterised by vacuolation and fusion of villi, and in the most severe cases, loss of epithelial integrity in villi tips. In the liver the primary effects were glycogen depletion and lipidosis. These changes were typical of a generalised stress response. While histology endpoints may prove to be the most sensitive indicators of dietary endosulfan exposure, the organismal relevance of these structural changes must be considered in the absence of effects in other biomarkers at dietary levels less than 710 {mu}g kg{sup -1}.

Fate of Tetracapsuloides bryosalmonae (Myxozoa) after infection of brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss.

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Kumar, Gokhlesh; Abd-Elfattah, Ahmed; Saleh, Mona; El-Matbouli, Mansour

2013-11-25

Tetracapsuloides bryosalmonae (Myxozoa) is the causative agent of proliferative kidney disease in salmonids. We assessed differences in intensity of T. bryosalmonae infection between brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss from the clinical phase of infection onwards. Specific pathogen-free fish were exposed to T. bryosalmonae spores under controlled laboratory conditions and sampled at 6, 8, 10, 12, 14, and 17 wk post exposure (wpe), and the transmission of T. bryosalmonae from infected fish to the bryozoan Fredericella sultana was observed. Parasite load was determined in fish kidneys by quantitative real-time PCR (qRT-PCR), and parasite stages were detected in kidney, liver, and spleen tissues at different time points by immunohistochemistry. T. bryosalmonae was successfully transmitted from infected brown trout to F. sultana colonies but not from infected rainbow trout. Body length and weight of infected brown trout did not differ significantly from control brown trout during all time points, while length and weight of infected rainbow trout differed significantly compared to controls from 10 to 17 wpe. qRT-PCR revealed that parasite load was significantly higher in kidneys of brown trout compared with rainbow trout. Immunohistochemistry showed high numbers of intra-luminal stages (sporogonic stages) in kidneys of brown trout with low numbers of pre-sporogonic stages. Sporogonic stages were not seen in kidneys of rainbow trout; only high numbers of pre-sporogonic stages were detected. Numbers of pre-sporogonic stages were low in the spleen and liver of brown trout but high in rainbow trout. These data confirmed that there are differences in the development and infection progress of T. bryosalmonae between brown trout and rainbow trout.

Fate of Tetracapsuloides bryosalmonae (Myxozoa) after infection of brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss

Science.gov (United States)

Kumar, Gokhlesh; Abd-Elfattah, Ahmed; Saleh, Mona; El-Matbouli, Mansour

2014-01-01

Tetracapsuloides bryosalmonae (Myxozoa) is the causative agent of proliferative kidney disease in salmonids. We assessed differences in intensity of T. bryosalmonae infection between brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss from the clinical phase of infection onwards. Specific pathogen-free fish were exposed to T. bryosalmonae spores under controlled laboratory conditions and sampled at 6, 8, 10, 12, 14, and 17 wk post exposure (wpe), and the transmission of T. bryosalmonae from infected fish to the bryozoan Fredericella sultana was observed. Parasite load was determined in fish kidneys by quantitative real-time PCR (qRT-PCR), and parasite stages were detected in kidney, liver, and spleen tissues at different time points by immunohistochemistry. T. bryosalmonae was successfully transmitted from infected brown trout to F. sultana colonies but not from infected rainbow trout. Body length and weight of infected brown trout did not differ significantly from control brown trout during all time points, while length and weight of infected rainbow trout differed significantly compared to controls from 10 to 17 wpe. qRT-PCR revealed that parasite load was significantly higher in kidneys of brown trout compared with rainbow trout. Immunohistochemistry showed high numbers of intra-luminal stages (sporogonic stages) in kidneys of brown trout with low numbers of pre-sporogonic stages. Sporogonic stages were not seen in kidneys of rainbow trout; only high numbers of pre-sporogonic stages were detected. Numbers of pre-sporogonic stages were low in the spleen and liver of brown trout but high in rainbow trout. These data confirmed that there are differences in the development and infection progress of T. bryosalmonae between brown trout and rainbow trout. PMID:24270019

La pesca de sardina, Sardinella aurita (Teleostei: Clupeidae asociada con la variabilidad ambiental del ecosistema de surgencia costera de Nueva Esparta, Venezuela

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Leo W González

2007-03-01

Full Text Available Se comparó la pesca de sardina (Sardinella aurita con algunos parámetros climáticos y meteorológicos del ecosistema de surgencia costera de El Morro, Nueva Esparta, Venezuela. Para el período 1996-2000, se aplicaron los modelos de regresión lineal simple y múltiple a los datos de captura en función de la velocidad del viento, temperatura superficial del mar, temperatura del aire y pluviosidad. Hubo una correlación positiva de la captura con la velocidad del viento, y una negativa con temperatura superficial del mar, temperatura del aire y pluviosidad. El modelo de regresión múltiple con intercepto mostró un ajuste bajo, por tal razón se aplicó un modelo de regresión sin intercepto, el cual mejoró significativamente el ajuste. También se aplicó el método de selección de variables "hacia adelante", encontrándose que las variables independientes viento y temperatura del aire guardan relación significativa con la captura de sardina a tiempo real (pAssociation of sardine fishery, Sardinella aurita (Teleostei: Clupeidae and environmental variability of the coastal upwelling ecosystem of Nueva Esparta, Venezuela. The present research is an analysis of Spanish sardine fishing (Sardinella aurita associated with some climatic and meteorologic parameters of the ecosystem from El Morro Nueva Esparta, Venezuela. The catch and environmental data from the area were taken in the period 1996-2000. Catch data as a function of wind speed, sea surface temperature, air temperature and rain were analyzed by means of simple lineal regression and multiple models. We found a positive correlation of catch with wind speed, and a negative correlation with sea surface temperature, air temperature, and rain. The multiple regression model with intercept had a poor fit, therefore, we made a model without intercept, which improve greatly the fit. A selection of the variables using the forward procedure verified that the independent variables "wind speed

Effects of steroids and sex reversal on intestinal absorption of L-[14C]leucine in vivo, in rainbow trout, Salmo gairdneri

International Nuclear Information System (INIS)

Habibi, H.R.; Ince, B.W.

1983-01-01

The effects of steroids (17 alpha-methyltestosterone (MT), 17 beta-oestradiol (E2)), and of sex reversal (XX male) on intestinal absorption and accumulation of L-[ 14 C]leucine (5 mM), were investigated in unanaesthetized rainbow trout (Salmo gairdneri), using an in vivo gut perfusion technique. Each steroid was luminally perfused through the gut at a concentration of 50 micrograms/ml perfusate, during five separate perfusions carried out on the same fish at 30-min intervals (perfusion periods 1 to 5), for a total of 120 min at 14 degrees. Experiments were also conducted on masculinized, genetically female trout (XX male) with steroid-free perfusate. MT treatment significantly increased the intestinal absorption of radioleucine during periods 1 and 2, whilst E2 was without effect. Neither MT nor E2 influenced intestinal accumulation (mid- and hindgut) of radioleucine, and accumulation of 14 C-solutes in skeletal muscle. Sex reversal, however, whilst having no effect on leucine absorption, nevertheless significantly increased intestinal accumulation of radioleucine, and accumulation of 14 C-solutes in skeletal muscle. The effects observed in the present study are in agreement with previous work in trout using everted gut sac preparations. It is suggested that the growth-promoting effects of anabolic-androgenic steroids in fish may be partly explained by their action on gastrointestinal function

Effectiveness of emamectin benzoate for treatment of Lepeophtheirus salmonis on farmed Atlantic salmon Salmo salar in the Bay of Fundy, Canada.

Science.gov (United States)

Jones, Patti G; Hammell, K Larry; Dohoo, Ian R; Revie, Crawford W

2012-12-03

Emamectin benzoate (an avermectin chemotherapeutant administered to fish as an in-feed treatment) has been used to treat infestations of sea lice Lepeophtheirus salmonis on farmed Atlantic salmon Salmo salar in the Bay of Fundy, New Brunswick, Canada, since 1999. This retrospective study examined the effectiveness of 114 emamectin benzoate treatment episodes from 2004 to 2008 across 54 farms. Study objectives were to establish whether changes in the effectiveness of emamectin benzoate were present for this period, examine factors associated with treatment outcome, and determine variables that influenced differences in L. salmonis abundance after treatment. The analysis was carried out in 2 parts: first, trends in treatment effectiveness and L. salmonis abundance were explored, and second, statistical modelling (linear and logistic regression) was used to examine the effects of multiple variables on post-treatment abundance and treatment outcome. Post-treatment sea lice abundance increased in the later years examined. Mean abundance differed between locations in the Bay of Fundy, and higher numbers were found at farms closer to the mainland and lower levels were found in the areas around Grand Manan Island. Treatment effectiveness varied by geographical region and decreased over time. There was an increased risk for unsuccessful treatments in 2008, and treatments applied during autumn months were more likely to be ineffective than those applied during summer months.

Age dependence of the accumulation of organochlorine pollutants in brown trout (Salmo trutta) from a remote high mountain lake (Redo, Pyrenees)

International Nuclear Information System (INIS)

Vives, I.; Grimalt, J.O.; Ventura, M.; Catalan, J.; Rosseland, B.O.

2005-01-01

Polychlorobiphenyls (PCBs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB) and DDT were examined in the muscle of brown trout (Salmo trutta) from a high mountain lake located in the Pyrenees (Catalonia, Spain) that was used as a model of these lacustrine environments. Results indicate that fish age is the main factor of variability among specimens in this population that is subjected to atmospheric inputs of the organochlorine compounds (OC). Increases of 2- and 20-fold between fish aged 1 year and 15 years old are found. The observed pattern cannot be explained in terms of fish size, condition factor, or muscle lipid content. Higher molecular weight compounds (higher lipophilicity) are better correlated with fish age than low molecular weight compounds. A transformation from 4,4'-DDT to 4,4'-DDE occurs in fish after ingestion; this results in amplified age-dependent signals, especially in male specimens. In contrast, PCB congener no. 180 has lower age dependence than the general OC group, which could be due to its high hydrophobicity (log K ow > 7). In any case, selective accumulation of hydrophobic compounds is already observed among younger fish (age, 1 year). Due to this effect, the relative OC composition does not reflect the main OC pollutants in the lake waters. - Trout in high mountain lakes display age-dependent accumulation of certain organochlorine pollutants

Age dependence of the accumulation of organochlorine pollutants in brown trout (Salmo trutta) from a remote high mountain lake (Redo, Pyrenees)

Energy Technology Data Exchange (ETDEWEB)

Vives, I. [Department of Environmental Chemistry, Institute of Chemical and Environmental Research (CSIC), Jordi Girona 18, 08034-Barcelona, Catalonia (Spain); Grimalt, J.O. [Department of Environmental Chemistry, Institute of Chemical and Environmental Research (CSIC), Jordi Girona 18, 08034-Barcelona, Catalonia (Spain)]. E-mail: jgoqam@cid.csic.es; Ventura, M. [Limnology Group (CSIC-UB), Centre for Advanced Studies of Blanes (CEAB-CSIC), Acces Cala St. Francesc, 14, Blanes 17300, Catalonia (Spain); Catalan, J. [Limnology Group (CSIC-UB), Centre for Advanced Studies of Blanes (CEAB-CSIC), Acces Cala St. Francesc, 14, Blanes 17300, Catalonia (Spain); Rosseland, B.O. [Norwegian Institute for Water Research (NIVA), P.O.B. 173 Kjelsaas, N-0411 Oslo (Norway); Institute for Biology and Nature Conservation, The Agricultural University of Norway (NLH) (Norway)

2005-01-01

Polychlorobiphenyls (PCBs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB) and DDT were examined in the muscle of brown trout (Salmo trutta) from a high mountain lake located in the Pyrenees (Catalonia, Spain) that was used as a model of these lacustrine environments. Results indicate that fish age is the main factor of variability among specimens in this population that is subjected to atmospheric inputs of the organochlorine compounds (OC). Increases of 2- and 20-fold between fish aged 1 year and 15 years old are found. The observed pattern cannot be explained in terms of fish size, condition factor, or muscle lipid content. Higher molecular weight compounds (higher lipophilicity) are better correlated with fish age than low molecular weight compounds. A transformation from 4,4'-DDT to 4,4'-DDE occurs in fish after ingestion; this results in amplified age-dependent signals, especially in male specimens. In contrast, PCB congener no. 180 has lower age dependence than the general OC group, which could be due to its high hydrophobicity (log K{sub ow} > 7). In any case, selective accumulation of hydrophobic compounds is already observed among younger fish (age, 1 year). Due to this effect, the relative OC composition does not reflect the main OC pollutants in the lake waters. - Trout in high mountain lakes display age-dependent accumulation of certain organochlorine pollutants.

Development and validation of a high density SNP genotyping array for Atlantic salmon (Salmo salar)

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2014-01-01

Background Dense single nucleotide polymorphism (SNP) genotyping arrays provide extensive information on polymorphic variation across the genome of species of interest. Such information can be used in studies of the genetic architecture of quantitative traits and to improve the accuracy of selection in breeding programs. In Atlantic salmon (Salmo salar), these goals are currently hampered by the lack of a high-density SNP genotyping platform. Therefore, the aim of the study was to develop and test a dense Atlantic salmon SNP array. Results SNP discovery was performed using extensive deep sequencing of Reduced Representation (RR-Seq), Restriction site-Associated DNA (RAD-Seq) and mRNA (RNA-Seq) libraries derived from farmed and wild Atlantic salmon samples (n = 283) resulting in the discovery of > 400 K putative SNPs. An Affymetrix Axiom® myDesign Custom Array was created and tested on samples of animals of wild and farmed origin (n = 96) revealing a total of 132,033 polymorphic SNPs with high call rate, good cluster separation on the array and stable Mendelian inheritance in our sample. At least 38% of these SNPs are from transcribed genomic regions and therefore more likely to include functional variants. Linkage analysis utilising the lack of male recombination in salmonids allowed the mapping of 40,214 SNPs distributed across all 29 pairs of chromosomes, highlighting the extensive genome-wide coverage of the SNPs. An identity-by-state clustering analysis revealed that the array can clearly distinguish between fish of different origins, within and between farmed and wild populations. Finally, Y-chromosome-specific probes included on the array provide an accurate molecular genetic test for sex. Conclusions This manuscript describes the first high-density SNP genotyping array for Atlantic salmon. This array will be publicly available and is likely to be used as a platform for high-resolution genetics research into traits of evolutionary and economic importance in

Uptake and effects of 2, 4, 6 - trinitrotoluene (TNT) in juvenile Atlantic salmon (Salmo salar).

Science.gov (United States)

Mariussen, Espen; Stornes, Siv Marie; Bøifot, Kari Oline; Rosseland, Bjørn Olav; Salbu, Brit; Heier, Lene Sørlie

2018-01-01

Organ specific uptake and depuration, and biological effects in Atlantic salmon (Salmo salar) exposed to 2, 4, 6-trinitrotoluene (TNT) were studied. Two experiments were conducted, the first using radiolabeled TNT ( 14 C-TNT, 0.16mg/L) to study uptake (48h) and depuration (48h), while the second experiment focused on physiological effects in fish exposed to increasing concentrations of unlabeled TNT (1μg-1mg/L) for 48h. The uptake of 14 C-TNT in the gills and most of the organs increased rapidly during the first 6h of exposure (12h in the brain) followed by a rapid decrease even though the fish were still exposed to TNT in the water. The radioactivity in the gall bladder reached a maximum after 55h, 7h after the transfer to the clean water. A high concentration of 14 C-TNT in the gall bladder indicates that TNT is excreted through the gall bladder. Mortality (2 out of 14) was observed at a concentration of 1mg/L, and the surviving fish had hemorrhages in the dorsal muscle tissue near the spine. Analysis of the physiological parameters in blood from the high exposure group revealed severe effects, with an increase in the levels of glucose, urea and HCO 3 , and a decrease in hematocrit and the levels of Cl and hemoglobin. No effects on blood physiology were observed in fish exposed to the lower concentrations of TNT (1-100μg/L). TNT and the metabolites 2-amino-4,6-dinitrotoluene (2-ADNT) and 4-amino-2,6-dinitrotoluene (4-ADNT) were found in the muscle tissue, whereas only 2-ADNT and 4-ADNT were found in the bile. The rapid excretion and estimated bioconcentration factors (range of 2-18 after 48h in gills, blood, liver, kidney, muscle and brain) indicated a low potential for bioaccumulation of TNT. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparative responses to endocrine disrupting compounds in early life stages of Atlantic salmon, Salmo salar

Science.gov (United States)

Duffy, Tara A.; Iwanowicz, Luke R.; McCormick, Stephen D.

2014-01-01

Atlantic salmon (Salmo salar) are endangered anadromous fish that may be exposed to feminizing endocrine disrupting compounds (EDCs) during early development, potentially altering physiological capacities, survival and fitness. To assess differential life stage sensitivity to common EDCs, we carried out short-term (four day) exposures using three doses each of 17α-ethinylestradiol (EE2), 17β-estradiol (E2), and nonylphenol (NP) on four early life stages; embryos, yolk-sac larvae, feeding fry and one year old smolts. Differential response was compared using vitellogenin (Vtg, a precursor egg protein) gene transcription. Smolts were also examined for impacts on plasma Vtg, cortisol, thyroid hormones (T4/T3) and hepatosomatic index (HSI). Compound-related mortality was not observed in any life stage, but Vtg mRNA was elevated in a dose-dependent manner in yolk-sac larvae, fry and smolts but not in embyos. The estrogens EE2 and E2 were consistently stronger inducers of Vtg than NP. Embryos responded significantly to the highest concentration of EE2 only, while older life stages responded to the highest doses of all three compounds, as well as intermediate doses of EE2 and E2. Maximal transcription was greater for fry among the three earliest life stages, suggesting fry may be the most responsive life stage in early development. Smolt plasma Vtg was also significantly increased, and this response was observed at lower doses of each compound than was detected by gene transcription suggesting this is a more sensitive indicator at this life stage. HSI was increased at the highest doses of EE2 and E2 and plasma T3 decreased at the highest dose of EE2. Our results indicate that all life stages after hatching are potentially sensitive to endocrine disruption by estrogenic compounds and that physiological responses were altered over a short window of exposure, indicating the potential for these compounds to impact fish in the wild.

Comparative responses to endocrine disrupting compounds in early life stages of Atlantic salmon, Salmo salar.

Science.gov (United States)

Duffy, T A; Iwanowicz, L R; McCormick, S D

2014-07-01

Atlantic salmon (Salmo salar) are endangered anadromous fish that may be exposed to feminizing endocrine disrupting compounds (EDCs) during early development, potentially altering physiological capacities, survival and fitness. To assess differential life stage sensitivity to common EDCs, we carried out short-term (4 day) exposures using three doses each of 17 α-ethinylestradiol (EE2), 17 β-estradiol (E2), and nonylphenol (NP) on four early life stages; embryos, yolk-sac larvae, feeding fry and 1 year old smolts. Differential response was compared using vitellogenin (Vtg, a precursor egg protein) gene transcription. Smolts were also examined for impacts on plasma Vtg, cortisol, thyroid hormones (T4/T3) and hepatosomatic index (HSI). Compound-related mortality was not observed in any life stage, but Vtg mRNA was elevated in a dose-dependent manner in yolk-sac larvae, fry and smolts but not in embryos. The estrogens EE2 and E2 were consistently stronger inducers of Vtg than NP. Embryos responded significantly to the highest concentration of EE2 only, while older life stages responded to the highest doses of all three compounds, as well as intermediate doses of EE2 and E2. Maximal transcription was greater for fry among the three earliest life stages, suggesting fry may be the most responsive life stage in early development. Smolt plasma Vtg was also significantly increased, and this response was observed at lower doses of each compound than was detected by gene transcription suggesting plasma Vtg is a more sensitive indicator at this life stage. HSI was increased at the highest doses of EE2 and E2, and plasma T3 was decreased at the highest dose of EE2. Our results indicate that all life stages are potentially sensitive to endocrine disruption by estrogenic compounds and that physiological responses were altered over a short window of exposure, indicating the potential for these compounds to impact fish in the wild. Copyright © 2014 Elsevier B.V. All rights

Early stress responses in Atlantic salmon (Salmo salar) exposed to environmentally relevant concentrations of uranium

International Nuclear Information System (INIS)

Song You; Salbu, Brit; Heier, Lene Sørlie; Teien, Hans-Christian; Lind, Ole-Christian; Oughton, Deborah; Petersen, Karina; Rosseland, Bjørn Olav; Skipperud, Lindis; Tollefsen, Knut Erik

2012-01-01

Uranium (U) is a naturally occurring heavy metal widely used in many military and civil applications. Uranium contamination and the associated potential adverse effects of U on the aquatic environment have been debated during recent years. In order to understand the effect and mode of action (MoA) of U in vivo, juvenile Atlantic salmon (Salmo salar) were exposed to 0.25 mg/L, 0.5 mg/L and 1.0 mg/L waterborne depleted uranyl acetate, respectively, in a static system for 48 h. The U concentrations in the gill and liver were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) and the resulting biological effects were determined by a combination of analysis of gene expression and micronuclei formation. The hepatic transcriptional level of 12 biomarker genes from four stress–response categories, including oxidative stress (γ-glutamyl cysteine synthetase (GCS), glutathione reductase (GR), glutathione peroxidase (GPx)), DNA damage and repair (P53, cyclin-dependent kinase inhibitor 1 (P21), growth arrest and DNA damage-inducible gene gamma (Gadd45G), proliferating cell nuclear antigen (PCNA), Rad51), apoptosis (Bcl2-associated X protein (BAX), Bcl-x, Caspase 6A,) and protein degradation (Ubiquitin) were evaluated by quantitative real-time polymerase chain reaction (q-rtPCR). The results clearly showed accumulation of U in the gill and liver with increasing concentrations of U in the exposure water. The effects of U on differential hepatic gene expression also occurred in a concentration-dependent manner, although deviations from ideal concentration–response relationships were observed at the highest U concentration (1.0 mg/L). All the genes tested were found to be up-regulated by U while no significant micronuclei formation was identified. The results suggest that U may cause oxidative stress in fish liver at concentrations greater than 0.25 mg/L, giving rise to clear induction of several toxicologically relevant biomarker genes, although no significant

The effects of different levels of Beta Plus on growth performance, microbial flora and blood parameters of Caspian trout, Salmo caspius (Kessler, 1877

Directory of Open Access Journals (Sweden)

Sadegh Krimzadeh

2014-11-01

Full Text Available This study was conducted to evaluate the effects of Beta plus probiotic, a mixture of Bacillius leicheniformic and Bacillius subtilis, on the growth performance and intestinal microbial flora of Caspian trout (Salmo caspius. A basal diet was formulated and supplemented with Beta plus at 0, 0.5 and 1 g kg-1, leading to three experimental diets. Each experimental diet was randomly assigned to quadruple 1500 L tanks. The Caspian trout with an initial weight of 108.7 ± 1.8 g were randomly distributed in the experimental tanks. The results showed that inclusion of dietary Beta plus significantly increased the final weight and specific growth rate (SGR of Caspian trout compared to those the control treatment. The feed conversion ratio (FCR was also improved significantly after probiotic administration to the experimental fish. However, the body composition and blood parameters were not influenced by the probiotic inclusion. Total count of Gram positive and negative bacteria in the intestine of the fish increased by feeding on diet contained 1 g kg-1 Beta Plus (P<0.05. In conclusion, administration of the probiotic Beta plus can improve the nutrient efficiency and growth performance of Caspian trout confirming the positive effect of a mixture of Bacillus spp.

Effects of dietary n-3 fatty acids on Toll-like receptor activation in primary leucocytes from Atlantic salmon (Salmo salar).

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Arnemo, Marianne; Kavaliauskis, Arturas; Andresen, Adriana Magalhaes Santos; Bou, Marta; Berge, Gerd Marit; Ruyter, Bente; Gjøen, Tor

2017-08-01

The shortage of the n-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on the international markets has led to increasing substitution of fish oil by plant oils in Atlantic salmon (Salmo salar) feed and thereby reducing the EPA and DHA content in salmon. However, the minimum required levels of these fatty acids in fish diets for securing fish health are unknown. Fish were fed with 0, 1 or 2% EPA or DHA alone or in combination of both over a period, growing from 50 to 400 g. Primary head kidney leucocytes were isolated and stimulated with Toll-like receptor (TLR) ligands to determine if EPA and DHA deficiency can affect expression of important immune genes and eicosanoid production. Several genes related to viral immune response did not vary between groups. However, there was a tendency that the high-level EPA and DHA groups expressed lower levels of IL-1β in non-stimulated leucocytes. These leucocytes were also more responsive to the TLR ligands, inducing higher expression levels of IL-1β and Mx1 after stimulation. The levels of prostaglandin E2 and leukotriene B4 in serum and media from stimulated leucocytes were lower in both low and high EPA and DHA groups. In conclusion, leucocytes from low EPA and DHA groups seemed to be less responsive towards immunostimulants, like TLR ligands, indicating that low levels or absence of dietary EPA and DHA may have immunosuppressive effects.

Antioxidant properties of salmon (Salmo salar L.) protein fraction hydrolysates revealed following their ex vivo digestion and in vitro hydrolysis.

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Borawska, Justyna; Darewicz, Małgorzata; Pliszka, Monika; Vegarud, Gerd E

2016-06-01

Salmon (Salmo salar L.) myofibryllar protein (MP) and sarcoplasmic protein (SP) were digested with human gastric and duodenal juices and hydrolysed in vitro with commercial pepsin and Corolase PP. The digestion after duodenal juice/Corolase PP caused almost complete breakdown of peptide bonds in MP and SP. The DPPH(•) scavenging activity of proteins decreased during both ex vivo digestion and in vitro hydrolysis. The highest value of DPPH(•) scavenging activity was shown for the gastric digest of SP (8.88 ± 0.87%). The ABTS(+•) scavenging activity of MP and SP increased during digestion/hydrolysis. The duodenal digest of SP was characterised by the highest value of ABTS(+•) scavenging activity (72.7 ± 1.2%). In turn, the highest value of ferric-reducing power was determined for the gastric digest of SP (84.8 ± 0.2%). Salmon antioxidant peptides Phe-Ile-Lys-Lys, His-Leu, Ile-Tyr, Pro-His-Leu, Pro-Trp, Val-Pro-Trp were identified in both ex vivo digested and in vitro hydrolysed MP and SP. An antioxidant peptide, Val-Tyr, was additionally detected in the in vitro hydrolysate of SP. The results indicate the salmon myofibrillar and sarcoplasmic protein fractions as potential sources of antioxidant peptides that could be released in the gastrointestinal tract but their amino acid sequence and quantification vary. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Salmo salar and Esox lucius full-length cDNA sequences reveal changes in evolutionary pressures on a post-tetraploidization genome

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Holt Robert A

2010-04-01

Full Text Available Abstract Background Salmonids are one of the most intensely studied fish, in part due to their economic and environmental importance, and in part due to a recent whole genome duplication in the common ancestor of salmonids. This duplication greatly impacts species diversification, functional specialization, and adaptation. Extensive new genomic resources have recently become available for Atlantic salmon (Salmo salar, but documentation of allelic versus duplicate reference genes remains a major uncertainty in the complete characterization of its genome and its evolution. Results From existing expressed sequence tag (EST resources and three new full-length cDNA libraries, 9,057 reference quality full-length gene insert clones were identified for Atlantic salmon. A further 1,365 reference full-length clones were annotated from 29,221 northern pike (Esox lucius ESTs. Pairwise dN/dS comparisons within each of 408 sets of duplicated salmon genes using northern pike as a diploid out-group show asymmetric relaxation of selection on salmon duplicates. Conclusions 9,057 full-length reference genes were characterized in S. salar and can be used to identify alleles and gene family members. Comparisons of duplicated genes show that while purifying selection is the predominant force acting on both duplicates, consistent with retention of functionality in both copies, some relaxation of pressure on gene duplicates can be identified. In addition, there is evidence that evolution has acted asymmetrically on paralogs, allowing one of the pair to diverge at a faster rate.

Local and systemic humoral immune response in farmed Atlantic salmon (Salmo salar L.) under a natural amoebic gill disease outbreak.

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Marcos-López, Mar; Espinosa Ruiz, Cristóbal; Rodger, Hamish D; O'Connor, Ian; MacCarthy, Eugene; Esteban, M Ángeles

2017-07-01

Amoebic gill disease (AGD), caused by the protozoan parasite Neoparamoeba perurans, is one of the most significant infectious diseases for Atlantic salmon (Salmo salar L.) mariculture. The present study investigated the humoral immune response (both local in gill mucus and systemic in serum) of farmed Atlantic salmon naturally infected with N. perurans in commercial sea pens, at two different stages of the disease and after freshwater treatment. Parameters analysed included activity of immune related enzymes (i.e. lysozyme, peroxidase, protease, anti-protease, esterase, alkaline phosphatase), IgM levels, and the terminal carbohydrate profile in the gill mucus. Overall, greater variations between groups were noted in the immune parameters determined in gill mucus than the equivalent in the serum. In gill mucus, IgM levels and peroxidase, lysozyme, esterase and protease activities were decreased in fish showing longer exposure time to the infection and higher disease severity, then showed a sequential increase after treatment. Results obtained highlight the capacity of gills to elicit a local response to the infection, indicate an impaired immune response at the later stages of the disease, and show partial reestablishment of the host immune status after freshwater treatment. In addition to providing data on the humoral response to AGD, this study increases knowledge on gill mucosal humoral immunity, since some of the parameters were analysed for the first time in gill mucus. Copyright © 2017 Elsevier Ltd. All rights reserved.

Metabolism of sn-1(3)-Monoacylglycerol and sn-2-Monoacylglycerol in Caecal Enterocytes and Hepatocytes of Brown Trout (Salmo trutta).

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Li, Keshuai; Olsen, Rolf Erik

2017-01-01

sn-2-Monoacylglycerol (2-MAG) and sn-1(3)-monoacylglycerol [1(3)-MAG] are important but yet little studied intermediates in lipid metabolism. The current study compared the metabolic fate of 2-MAG and 1(3)-MAG in isolated caecal enterocytes and hepatocytes of brown trout (Salmo trutta). 1(3)-Oleoyl [9,10-3H(N)]-glycerol and 2-Oleoyl [9,10-3H(N)]-glycerol were prepared by pancreatic lipase digestion of triolein [9,10-3H(N)]. The 1(3)-MAG and 2-MAG were efficiently absorbed by enterocytes and hepatocytes at similar rates. The 2-MAG was quickly resynthesized into TAG through the monoacylglycerol acyltransferase (EC: 2.3.1.22, MGAT) pathway in both tissues, whereas 1(3)-MAG was processed into TAG and phospholipids at a much slower rate, suggesting 2-MAG was the preferred substrates for MGAT. Further analysis showed that 1(3)-MAG was synthesized into 1,3-DAG, but there were no accumulation of 1,3-DAG in either enterocytes or hepatocytes, which contrasts that of mammalian studies. Some of the 1(3)-MAG may be acylated to 1,2(2,3)-DAG and then utilized for TAG synthesis. Alternatively, 1(3)-MAG can be hydrolyzed to free fatty acid and glycerol, and re-synthesized into TAG through the glycerol-3-phosphate (Gro-3-P) pathway. The overall data suggested that the limiting step of the intracellular 1(3)-MAG metabolism is the conversion of 1(3)-MAG itself.

Loaches and the environment in two provinces in Northern Vietnam

Czech Academy of Sciences Publication Activity Database

Petrtýl, M.; Bohlen, Jörg; Kalous, L.; Bui, A.T.; Chaloupková, P.

2011-01-01

Roč. 60, č. 4 (2011), 368-374 ISSN 0139-7893 R&D Projects: GA ČR GA206/05/2556; GA ČR GA206/08/0637 Grant - others:MZe(CZ) 29/Mze/B/08-10 Institutional research plan: CEZ:AV0Z50450515 Keywords : biodiversity * conservation * Teleostei Subject RIV: EG - Zoology Impact factor: 0.554, year: 2011

Reduced host-specificity in a parasite infecting non-littoral Lake Tanganyika cichlids evidenced by intraspecific morphological and genetic diversity

Czech Academy of Sciences Publication Activity Database

Kmentová, N.; Gelnar, M.; Mendlová, M.; Van Steenberge, M.; Koblmüller, Stephan; Vanhove, M. P. M.

2016-01-01

Roč. 6, č. 39605 (2016), č. článku 39605. ISSN 2045-2322 R&D Projects: GA ČR(CZ) GBP505/12/G112 Institutional support: RVO:68081766 Keywords : Monogenean parasites * Ancyrocephalidae * adaptive radiation * statistical tests * population growth * DNA polymorphism * fish families * Teleostei * phylogeny Subject RIV: EG - Zoology Impact factor: 4.259, year: 2016

NEW SPECIES OF DEMIDOSPERMUS (MONOGENEA: DACTYLOGYRIDAE) OF PIMELODID CATFISH (SILURIFORMES) FROM PERUVIAN AMAZONIA AND THE REASSIGNMENT OF UROCLEIDOIDES LEBEDEVI KRITSKY AND THATCHER, 1976

Czech Academy of Sciences Publication Activity Database

Mendoza-Palmero, Carlos Alonso; Scholz, Tomáš

2011-01-01

Roč. 97, č. 4 (2011), s. 586-592 ISSN 0022-3395 R&D Projects: GA MŠk LC522; GA ČR GD206/09/H026 Institutional research plan: CEZ:AV0Z60220518 Keywords : BRAZIL * ANCYROCEPHALINAE * TELEOSTEI * FISHES * GILLS Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.405, year: 2011

Crecimiento y mortalidad del pez Haemulon aurolineatum (Teleostei: Haemulidae en el suroeste de la isla de Margarita, Venezuela

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Edwis Bravo

2009-06-01

Full Text Available Se determinó el crecimiento y la mortalidad natural del pez cují (Haemulon aurolineatum del suroeste de la Isla de Margarita (julio 2005 -junio 2006, para lo cual se analizó una muestra constituida por 2 541 ejemplares recolectados de la pesca artesanal de Boca del Río. La relación talla-peso entre machos y hembras no mostró diferencias significativas en las pendientes "b" (p>0.05; ts=-1.69 ni en los interceptos "a" (p>0.05; ts=-1.01, por lo que se estableció una relación común para ambos sexos: P=0.038*LT2.87. A partir de los datos de distribución de frecuencia de tallas se estimó la longitud asintótica ( aplicando la rutina de Powell-Wetherall, y el coeficiente de crecimiento (k a través de la rutina ELEFAN I (Gayanilo et al. 1996. Posteriormente se empleó el análisis de la progresión modal, previa descomposición de la frecuencia de longitudes de acuerdo al método de Bhattacharya (1967, y se optimizaron las estimaciones de y k según el procedimiento de Gulland y Holt (1959. Los parámetros de crecimiento estimados (L8=24.2 cm y k=0.48 año-1 mostraron un crecimiento moderadamente rápido. Los datos de frecuencias de longitudes fueron ajustados al modelo de von Bertalanffy (1960, indicando una tendencia de tipo exponencial: crecimiento acelerado hasta los 2 años de edad, que luego se hizo lento hasta que el pez alcanzó la longitud máxima. La tasa de mortalidad natural fue alta (M=1.15 año-1, probablemente por alta depredación.Growth and mortality of the fish Haemulon aurolineatum (Teleostei: Haemulidae from Southwest of Margarita Island, Venezuela. We analyzed the growth and natural mortality of the fish known locally as cují (H. aurolineatum in the southwest of Margarita Island, July 2005 to June 2006. A sample of 1 378 males and 1 143 females from artisanal fishing vessels of Boca del Río was analyzed. The common relation for both sexes was expressed by the equation P=0.038*L2.87. The asymptotic length ( was

Crecimiento y mortalidad natural del pez Haemulon aurolineatum (Teleostei: Haemulidae del suroeste de la isla de Margarita, Venezuela

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Edwis Bravo

2009-09-01

Full Text Available Se determinó el crecimiento y la mortalidad natural del cují (Haemulon aurolineatum del suroeste de la isla de Margarita, entre julio 2005 hasta junio 2006, para lo cual se analizó una muestra de 2 541 ejemplares colectados de la pesca artesanal de Boca del Río. La relación talla-peso entre machos y hembras no mostró diferencias significativas en las pendientes "b" (p>0.05, ts = -1.69 ni en los interceptos "a" (p>0.05, ts = -1.01, por lo que se estableció una relación común para ambos sexos, expresada mediante el modelo P = 0.038*LT2.87. A partir de los datos de distribución de frecuencia de tallas se estimó la longitud asintótica (L∞ con la rutina de Powell-Wetherall, y el coeficiente de crecimiento (k con la rutina ELEFAN I (Gayanilo et al.1996. Se empleó el análisis de la progresión modal, previa descomposición de la frecuencia de longitudes de acuerdo al método de Bhattacharya (1967, y se optimizaron las estimaciones de L∞ y k según Gulland y Holt (1959. Los parámetros de crecimiento estimados (L∞ = 24.2 cm y k = 0.48 año-1 mostraron un crecimiento moderadamente rápido. Los datos de frecuencias de longitudes fueron ajustados al modelo de von Bertalanffy (1960, mostrando una tendencia de tipo exponencial, donde se observó un crecimiento acelerado hasta los 2 años de edad, que luego se hizo lento a medida que el pez alcanzó la longitud máxima. La tasa de mortalidad natural fue alta (M = 1.15 año-1, probablemente causada por alta depredación.Growth and natural mortality of the fish Haemulon aurolineatum (Teleostei: Haemulidae in the Southwest of Margarita Island, Venezuela. We analyzed the growth and natural mortality of the cují (Haemulon aurolineatum in the southwest of Margarita Island, from July 2005 through June 2006. A sample of 1 378 males and 1 143 females collected from Boca del Río artisanal fishing vessels was analyzed. The common relation for both sexes was expressed by the equation P=0.038*L2

Ontogenetic profile of innate immune related genes and their tissue-specific expression in brown trout, Salmo trutta (Linnaeus, 1758).

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Cecchini, Stefano; Paciolla, Mariateresa; Biffali, Elio; Borra, Marco; Ursini, Matilde V; Lioi, Maria B

2013-09-01

The innate immune system is a fundamental defense weapon of fish, especially during early stages of development when acquired immunity is still far from being completely developed. The present study aims at looking into ontogeny of innate immune system in the brown trout, Salmo trutta, using RT-PCR based approach. Total RNA extracted from unfertilized and fertilized eggs and hatchlings at 0, 1 h and 1, 2, 3, 4, 5, 6, 7 weeks post-fertilization was subjected to RT-PCR using self-designed primers to amplify some innate immune relevant genes (TNF-α, IL-1β, TGF-β and lysozyme c-type). The constitutive expression of β-actin was detected in all developmental stages. IL-1β and TNF-α transcripts were detected from 4 week post-fertilization onwards, whereas TGF-β transcript was detected only from 7 week post-fertilization onwards. Lysozyme c-type transcript was detected early from unfertilized egg stage onwards. Similarly, tissues such as muscle, ovary, heart, brain, gill, testis, liver, intestine, spleen, skin, posterior kidney, anterior kidney and blood collected from adult brown trout were subjected to detection of all selected genes by RT-PCR. TNF-α and lysozyme c-type transcripts were expressed in all tissues. IL-1β and TGF-β transcripts were expressed in all tissues except for the brain and liver, respectively. Taken together, our results show a spatial-temporal expression of some key innate immune-related genes, improving the basic knowledge of the function of innate immune system at early stage of brown trout. Copyright © 2013 Elsevier Ltd. All rights reserved.

Accumulation of lead (Pb) in brown trout (Salmo trutta) from a lake downstream a former shooting range.

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Mariussen, Espen; Heier, Lene Sørlie; Teien, Hans Christian; Pettersen, Marit Nandrup; Holth, Tor Fredrik; Salbu, Brit; Rosseland, Bjørn Olav

2017-01-01

An environmental survey was performed in Lake Kyrtjønn, a small lake within an abandoned shooting range in the south of Norway. In Lake Kyrtjønn the total water concentrations of Pb (14µg/L), Cu (6.1µg/L) and Sb (1.3µg/L) were elevated compared to the nearby reference Lake Stitjønn, where the total concentrations of Pb, Cu and Sb were 0.76, 1.8 and 0.12µg/L, respectively. Brown trout (Salmo trutta) from Lake Kyrtjønn had very high levels of Pb in bone (104mg/kg w.w.), kidney (161mg/kg w.w.) and the gills (137mg/kg d.w), and a strong inhibition of the ALA-D enzyme activity were observed in the blood (24% of control). Dry fertilized brown trout eggs were placed in the small outlet streams from Lake Kyrtjønn and the reference lake for 6 months, and the concentrations of Pb and Cu in eggs from the Lake Kyrtjønn stream were significantly higher than in eggs from the reference. More than 90% of Pb accumulated in the egg shell, whereas more than 80% of the Cu and Zn accumulated in the egg interior. Pb in the lake sediments was elevated in the upper 2-5cm layer (410-2700mg/kg d.w), and was predominantly associated with redox sensitive fractions (e.g., organic materials, hydroxides) indicating low potential mobility and bioavailability of the deposited Pb. Only minor amounts of Cu and Sb were deposited in the sediments. The present work showed that the adult brown trout, as well as fertilized eggs and alevins, may be subjected to increased stress due to chronic exposure to Pb, whereas exposure to Cu, Zn and Sb were of less importance. Copyright © 2016 Elsevier Inc. All rights reserved.

Induction of gynogenetic and androgenetic haploid and doubled haploid development in the brown trout (Salmo trutta Linnaeus 1758).

Science.gov (United States)

Michalik, O; Dobosz, S; Zalewski, T; Sapota, M; Ocalewicz, K

2015-04-01

Gynogenetic and androgenetic brown trout (Salmo trutta Linnaeus 1758) haploids (Hs) and doubled haploids (DHs) were produced in the present research. Haploid development was induced by radiation-induced genetic inactivation of spermatozoa (gynogenesis) or eggs (androgenesis) before insemination. To provide DHs, gynogenetic and androgenetic haploid zygotes were subjected to the high pressure shock to suppress the first mitotic cleavage. Among haploids, gynogenetic embryos were showing lower mortality when compared to the androgenetic embryos; however, most of them die before the first feeding stage. Gynogenetic doubled haploids provided in the course of the brown trout eggs activation performed by homologous and heterologous sperm (rainbow trout) were developing equally showing hatching rates of 14.76 ± 2.4% and 16.14 ± 2.90% and the survival rates at the first feeding stage of 10.48 ± 3.48% and 12.78 ± 2.18%, respectively. Significantly, lower survival rate was observed among androgenetic progenies from the diploid groups with only few specimens that survived to the first feeding stage. Cytogenetic survey showed that among embryos from the diploid variants of the research, only gynogenetic individuals possessed doubled sets of chromosomes. Thus, it is reasonable to assume that radiation employed for the genetic inactivation of the brown trout eggs misaligned mechanism responsible for the cell divisions and might have delayed or even arrested the first mitotic cleavage in the androgenetic brown trout zygotes. Moreover, protocol for the radiation-induced inactivation of the paternal and maternal genome should be adjusted as some of the cytogenetically surveyed gynogenetic and androgenetic embryos exhibited fragments of the irradiated chromosomes. © 2015 Blackwell Verlag GmbH.

Coping with unpredictability: dopaminergic and neurotrophic responses to omission of expected reward in Atlantic salmon (Salmo salar L.).

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Vindas, Marco A; Sørensen, Christina; Johansen, Ida B; Folkedal, Ole; Höglund, Erik; Khan, Uniza W; Stien, Lars H; Kristiansen, Tore S; Braastad, Bjarne O; Øverli, Øyvind

2014-01-01

Comparative studies are imperative for understanding the evolution of adaptive neurobiological processes such as neural plasticity, cognition, and emotion. Previously we have reported that prolonged omission of expected rewards (OER, or 'frustrative nonreward') causes increased aggression in Atlantic salmon (Salmo salar). Here we report changes in brain monoaminergic activity and relative abundance of brain derived neurotrophic factor (BDNF) and dopamine receptor mRNA transcripts in the same paradigm. Groups of fish were initially conditioned to associate a flashing light with feeding. Subsequently, the expected food reward was delayed for 30 minutes during two out of three meals per day in the OER treatment, while the previously established routine was maintained in control groups. After 8 days there was no effect of OER on baseline brain stem serotonin (5-HT) or dopamine (DA) activity. Subsequent exposure to acute confinement stress led to increased plasma cortisol and elevated turnover of brain stem DA and 5-HT in all animals. The DA response was potentiated and DA receptor 1 (D1) mRNA abundance was reduced in the OER-exposed fish, indicating a sensitization of the DA system. In addition OER suppressed abundance of BDNF in the telencephalon of non-stressed fish. Regardless of OER treatment, a strong positive correlation between BDNF and D1 mRNA abundance was seen in non-stressed fish. This correlation was disrupted by acute stress, and replaced by a negative correlation between BDNF abundance and plasma cortisol concentration. These observations indicate a conserved link between DA, neurotrophin regulation, and corticosteroid-signaling pathways. The results also emphasize how fish models can be important tools in the study of neural plasticity and responsiveness to environmental unpredictability.

Speciation, uptake and toxicity of uranium in Atlantic Salmon (Salmo salar)

Energy Technology Data Exchange (ETDEWEB)

Teien, Hans-Christian; Hertel-Aas, Turid; Lind, Ole Christian; Skipperud, Lindis; Oughton, Deborah H.; Salbu, Brit [Norwegian University of Life Sciences (NMBU), Center of Excellence in Environmental Radioactivity (CERAD). P.O. Box 5003, N-1432 Aas (Norway); Thoerring, Haavard [Norwegian Radiation Protection Authority (NRPA), P.O. Box 55, N-1332 Oesteraas (Norway)

2014-07-01

To obtain information about the bioavailability of uranium (U) and its chemical toxicity, a significant number of Atlantic Salmon (Salmo salar) juveniles (in total about 800 fish) were exposure to commercial available depleted uranium (DU) in controlled experiments conducted in accordance with the OECD guidelines for acute toxicity tests. Speciation, gill accumulation and induced toxicity of U as a function of varying water concentrations of H{sup +}, Ca{sup 2+}, Mg{sup 2+}, Na{sup +} and K{sup +} as well as U were studied. In addition to recording mortality, blood samples were collected and analysed for general stress parameters (plasma Cl and glucose) prior to fish dissection and collection of different tissues. The observed dose-response demonstrated that varying concentrations of K{sup +}, Na{sup +} or Mg{sup 2+} had no apparent effect on the U induced toxicity in terms of 96 h LC50-values. U toxicity was, however, strongly dependent on pH. Reducing pH from about 6.7 to 6.0 or 5.5 reduced the LC50-value from 3.1 to 1.4 mg U/l. However, by increasing pH to 7.9, LC50-values increased to 25 mg/L. Fractionation of the exposure waters, demonstrated that U was present as dissolved species less than 10 kDa in size predominantly as anion, and that a fraction (30%) was present as U colloids ( 3-10 kDa). Furthermore, U accumulated in fish gills, and the accumulation of U in the fish gills increased with increasing U concentration in the water. U accumulation at >50 μg U/g dry weight gill was correlated with ion regulation problems and stress response in fish, reflected by reduced plasma Cl concentration and increased blood glucose, and mortality was observed at concentration levels >300 μg/g gill dry weight. Thus, toxic effects in fish were correlated to U concentration in gills, and the concentration of U in gills was highly dependent upon pH in water and the U speciation. As presented in detail on a poster at the present conference (Cagno et al.), U did not only

Characterization of full-length sequenced cDNA inserts (FLIcs) from Atlantic salmon (Salmo salar)

Science.gov (United States)

Andreassen, Rune; Lunner, Sigbjørn; Høyheim, Bjørn

2009-01-01

DNA libraries generated by SGP represent a valuable cCDS FLIc source. The conservation of 7-mers in 3'UTRs indicates that these motifs are functionally important. Identity between some of these 7-mers and miRNA target sequences suggests that they are miRNA targets in Salmo salar transcripts as well. PMID:19878547

Characterization of full-length sequenced cDNA inserts (FLIcs from Atlantic salmon (Salmo salar

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Lunner Sigbjørn

2009-10-01

suggests that the remaining cDNA libraries generated by SGP represent a valuable cCDS FLIc source. The conservation of 7-mers in 3'UTRs indicates that these motifs are functionally important. Identity between some of these 7-mers and miRNA target sequences suggests that they are miRNA targets in Salmo salar transcripts as well.

Effects of steroids and sex reversal on intestinal absorption of L-(/sup 14/C)leucine in vivo, in rainbow trout, Salmo gairdneri

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Habibi, H.R.; Ince, B.W.

1983-12-01

The effects of steroids (17 alpha-methyltestosterone (MT), 17 beta-oestradiol (E2)), and of sex reversal (XX male) on intestinal absorption and accumulation of L-(/sup 14/C)leucine (5 mM), were investigated in unanaesthetized rainbow trout (Salmo gairdneri), using an in vivo gut perfusion technique. Each steroid was luminally perfused through the gut at a concentration of 50 micrograms/ml perfusate, during five separate perfusions carried out on the same fish at 30-min intervals (perfusion periods 1 to 5), for a total of 120 min at 14 degrees. Experiments were also conducted on masculinized, genetically female trout (XX male) with steroid-free perfusate. MT treatment significantly increased the intestinal absorption of radioleucine during periods 1 and 2, whilst E2 was without effect. Neither MT nor E2 influenced intestinal accumulation (mid- and hindgut) of radioleucine, and accumulation of /sup 14/C-solutes in skeletal muscle. Sex reversal, however, whilst having no effect on leucine absorption, nevertheless significantly increased intestinal accumulation of radioleucine, and accumulation of /sup 14/C-solutes in skeletal muscle. The effects observed in the present study are in agreement with previous work in trout using everted gut sac preparations. It is suggested that the growth-promoting effects of anabolic-androgenic steroids in fish may be partly explained by their action on gastrointestinal function.

Effects of rearing density and dietary fat content on burst-swim performance and oxygen transport capacity in juvenile Atlantic salmon Salmo salar.

Science.gov (United States)

Hammenstig, D; Sandblom, E; Axelsson, M; Johnsson, J I

2014-10-01

The effects of hatchery rearing density (conventional or one third of conventional density) and feeding regime (high or reduced dietary fat levels) on burst-swim performance and oxygen transport capacity were studied in hatchery-reared Atlantic salmon Salmo salar, using wild fish as a reference group. There was no effect of rearing density or food regime on swimming performance in parr and smolts. The maximum swimming speed of wild parr was significantly higher than that of hatchery-reared conspecifics, while no such difference remained at the smolt stage. In smolts, relative ventricle mass was higher in wild S. salar compared with hatchery-reared fish. Moreover, wild S. salar had lower maximum oxygen consumption following a burst-swim challenge than hatchery fish. There were no effects of hatchery treatment on maximum oxygen consumption or relative ventricle mass. Haemoglobin and haematocrit levels, however, were lower in low-density fish than in fish reared at conventional density. Furthermore, dorsal-fin damage, an indicator of aggression, was similar in low-density reared and wild fish and lower than in S. salar reared at conventional density. Together, these results suggest that reduced rearing density is more important than reduced dietary fat levels in producing an S. salar smolt suitable for supplementary release. © 2014 The Fisheries Society of the British Isles.

Efecto de reducir la frecuencia de alimentación en la supervivencia, crecimiento, conversión y conducta alimenticia en juveniles de salmón del Atlántico Salmo salar (Linnaeus, 1758: experiencia a nivel productivo Effect of reducing the feeding frequency on the survival, growth, conversion, and feeding behavior of juvenile Atlantic salmon Salmo salar (Linnaeus, 1758: an experience at the productive level

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Héctor Flores

2012-09-01

Full Text Available En Chile, la mayoría de las empresas de cultivo de salmones en la fase parr alimentan a los peces con 24 raciones/día; por otra parte, el alimento en el estómago de los peces, puede permanecer cerca de 4 a 5 h. Este trabajo evalúa en base a procedimientos y protocolos productivos, la disminución en la frecuencia de raciones de alimento y su efecto en la supervivencia, crecimiento, conversión y conducta de alimentación de los peces. Se trabajó en condiciones normales de producción comercial, con aproximadamente 1.200.000 peces de 0,17 g durante cuatro meses. Hubo dos tratamientos, el control con 24 raciones/día y el ensayo, que al inicio de la experiencia se entrego 12 raciones/día y al finalizar la experiencia se proporcionó 4 raciones/día. Se emplearon cinco estanques de 18 m³ para cada tratamiento. La disminución en la frecuencia de alimentación, no afectó la supervivencia de Salmo salar, se obtuvo mayor crecimiento en los peces del ensayo, con mejor conversión de alimento, se logró reducción de alimento depositado en el fondo de los estanques y se visualizó mejor apetito en los peces.In Chile, most salmon-farming companies feed fish in the parr phase 24 rations/day. However, food can remain in fish stomachs for around four or five hours. Using productive procedures and protocols, this study evaluates less frequent food rations and how they affect the survival, growth, conversion, and feeding behavior of the fish. The study was conducted over four months under normal commercial production conditions, using approximately 1,200,000 fish of 0.17 g each. There were two treatments: the control, which received 24 rations/day, and the assay, which received 12 rations/day at the onset of the study and 4 rations/day at the end of this. Five tanks, each 18 m³, were used for each treatment. The lower feeding frequency did not affect the survival of Salmo salar. The fish in the assay obtained greater growth and had better food

Transcriptional changes in Atlantic salmon (Salmo salar) after embryonic exposure to road salt.

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Tollefsen, Knut Erik; Song, You; Kleiven, Merethe; Mahrosh, Urma; Meland, Sondre; Rosseland, Bjørn Olav; Teien, Hans-Christian

2015-12-01

Road salt is extensively used as a deicing chemical in road maintenance during winter and has in certain areas of the world led to density stratifications in lakes and ponds, and adversely impacted aquatic organisms in the recipients of the road run-off. Aquatic vertebrates such as fish have been particularly sensitive during fertilisation, as the fertilisation of eggs involves rapid uptake of the surrounding water, reduction in egg swelling and in ovo exposure to high road salt concentrations. The present study aimed to identify the persistent molecular changes occurring in Atlantic salmon (Salmo salar) eggs after 24h exposure to high concentrations (5000 mg/L) of road salt at fertilisation. The global transcriptional changes were monitored by a 60k salmonid microarray at the eyed egg stage (cleavage stage, 255 degree days after fertilisation) and identified a high number of transcripts being differentially regulated. Functional enrichment, pathway and gene-gene interaction analysis identified that the differentially expressed genes (DEGs) were mainly associated with toxiciologically relevant processes involved in osmoregulation, ionregulation, oxidative stress, metabolism (energy turnover), renal function and developmental in the embryos. Quantitative rtPCR analysis of selected biomarkers, identified by global transcriptomics, were monitored in the eggs for an extended range of road salt concentrations (0, 50, 100, 500 and 5000 mg/L) and revealed a positive concentration-dependent increase in cypa14, a gene involved in lipid turnover and renal function, and nav1, a gene involved in neuraxonal development. Biomarkers for osmoregulatory responses such as atp1a2, the gene encoding the main sodium/potassium ATP-fueled transporter for chloride ions, and txdc9, a gene involved in regulation of cell redox homeostasis (oxidative stress), displayed apparent concentration-dependency with exposure, although large variance in the control group precluded robust statistical

HPLC confirmatory method development for the determination of seven quinolones in salmon tissue (Salmo salar L.) validated according to the European Union Decision 2002/657/EC.

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Evaggelopoulou, Evaggelia N; Samanidou, Victoria F

2013-01-15

A confirmatory high pressure liquid chromatographic method for the determination of seven quinolone antibiotics in tissue of Atlantic salmon (Salmo salar L.) was developed. Ciprofloxacin (CIP), danofloxacin (DAN), enrofloxacin (ENR), sarafloxacin (SAR), oxolinic acid (OXO), nalidixic acid (NAL) and flumequine (FLU) were separated on a Perfectsil ODS-2 120 (250 mm × 4 mm, 5 μm) column by gradient elution with a mobile phase consisting of 0.1% trifluoroacetic acid (pH=1), acetonitrile and methanol at 25°C within 22 min. Analytes were monitored at 255 nm (for the determination of OXO, NAL and FLU) and 275 nm (for CIP, DAN, ENR and SAR) by means of photodiode array detector. Examined quinolones were isolated from salmon tissue by extraction with citrate buffer solution (pH=4.7) and purified by solid phase extraction using Oasis HLB (200mg/6 mL) cartridges. The developed method was fully validated in terms of selectivity, linearity, accuracy, precision, stability and sensitivity according to the European Union Decision 2002/657/EC. The accuracy of the method was additionally proved by its application to certified reference material of salmon tissue (BCR® 725). Copyright © 2012 Elsevier Ltd. All rights reserved.

Lactococcus lactis subsp. tructae subsp. nov. isolated from the intestinal mucus of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss).

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Pérez, Tania; Balcázar, José Luis; Peix, Alvaro; Valverde, Angel; Velázquez, Encarna; de Blas, Ignacio; Ruiz-Zarzuela, Imanol

2011-08-01

The species Lactococcus lactis currently includes three subspecies; L. lactis subsp. lactis and L. lactis subsp. cremoris, isolated from milk sources, and L. lactis subsp. hordniae, isolated from the leafhopper Hordnia circellata. In this study, three strains, designated L105(T), I3 and L101, were isolated from the intestinal mucus of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss). These strains were closely related to members of the species Lactococcus lactis. Strain L105(T) showed 99.4 % 16S rRNA gene sequence similarity to that of the type strains L. lactis subsp. lactis NCDO 604(T) and L. lactis subsp. hordniae NCDO 2181(T) and showed 99.9 % similarity to the type strain Lactococcus lactis subsp. cremoris NCDO 607(T). Analysis of two housekeeping genes, rpoB and recA, confirmed the close relationship between the novel strains and L. lactis subsp. cremoris with similarities of 99.3 and 99.7 %, respectively. The three strains could, however, be differentiated from their closest relatives on the basis of several phenotypic characteristics, as was the case for L. lactis subsp. lactis and L. lactis subsp. hordniae, which were also closely related on the basis of 16S rRNA, rpoB and recA gene sequence similarities. The strains isolated in this study represent a new subspecies, for which the name Lactococcus lactis subsp. tructae subsp. nov. is proposed. The type strain is L105(T) ( = LMG 24662(T)  = DSM 21502(T)).

Early life traits of farm and wild Atlantic salmon Salmo salar and first generation hybrids in the south coast of Newfoundland.

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Hamoutene, D; Perez-Casanova, J; Burt, K; Lush, L; Caines, J; Collier, C; Hinks, R

2017-06-01

This study examined fertilization rates, survival and early life-trait differences of pure farm, wild and first generation (F1) hybrid origin embryos after crossing farm and wild Atlantic salmon Salmo salar. Results show that despite a trend towards higher in vitro fertilization success for wild females, differences in fertilization success in river water are not significantly different among crosses. In a hatchery environment, wild females' progeny (pure wild and hybrids with wild maternal parent) hatched 7-11 days earlier than pure farm crosses and hybrids with farm maternal parents. In addition, pure wild progeny had higher total lengths (L T ) at hatch than pure farm crosses and hybrids. Directions in trait differences need to be tested in a river environment, but results clearly show the maternal influence on early stages beyond egg-size differences. Differences in L T were no longer significant at 70 days post hatch (shortly after the onset of exogenous feeding) showing the need to investigate later developmental stages to better assess somatic growth disparities due to genetic differences. Higher mortality rates of the most likely hybrids (farm female × wild male hybrids) at egg and fry stages and their delayed hatch suggest that these F1 hybrids might be less likely to survive the early larval stages than wild stocks. © 2017 Her Majesty the Queen in Right of Canada. Journal of Fish Biology © 2017 The Fisheries Society of the British Isles.

Establishment and characterization of a new cell line (SSP-9) derived from Atlantic salmon Salmo salar that expresses type I ifn.

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Rodriguez Saint-Jean, S; González, C; Monrás, M; Romero, A; Ballesteros, N; Enríquez, R; Perez-Prieto, S

2014-11-01

In the present work, the establishment and biological characterization of a new cell line, SSP-9, derived from the pronephros of the Atlantic salmon Salmo salar, are reported. These cells grew well in Leibovitz's (L15) medium supplemented with 10% foetal calf serum at temperatures from 15 to 25° C, and they have been sub-cultured over 100 passages to produce a continuous cell line with an epithelial-like morphology. The SSP-9 cells attached and spread efficiently at different plating densities, retaining 80% of cell viability after storage in liquid nitrogen. When karyotyped, the cells had 40-52 chromosomes, with a modal number of 48. Viral susceptibility tests showed that SSP-9 cells were susceptible to infectious pancreatic necrosis virus and infectious haematopoietic necrosis virus, producing infectious virus and regular cytopathic effects. Moreover, these cells could be stimulated by poly I:C, showing significant up-regulation in the expression of the genes that regulate immune responses, such as ifn and mx-1. SSP-9 cells constitutively express genes characteristic of macrophages, such as major histocompatibility complex (mhc-II) and interleukin 12b (il-12b), and flow cytometry assays confirmed that SSP-9 cells can be permanently transfected with plasmids expressing a reporter gene. Accordingly, this new cell line is apparently suitable for transgenic manipulation, and to study host cell-virus interactions and immune processes. © 2014 The Fisheries Society of the British Isles.

Contribuição ao conhecimento da ictiofauna do Manguezal de Cacha Pregos, Ilha de Itaparica, Baía de Todos os Santos, Bahia Contribution to knowledge of ichthyofauna of Mangrove Cacha Pregos, Itaparica island, Todos os Santos bay, Bahia

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Paulo Roberto Duarte Lopes

1998-01-01

Full Text Available A check-list of fishes collected in a mangrove in Cacha Pregos, south of ltaparic Island, State of Bahia, Brazil (about 13o07'S,38o48'W from 1988-1989 and 1991-1992 is presented. Fifteen orders, 46 families and 85 species (Teleostei except one Chondrichthyes were identified, represented specimens whose adults live in different marine ecossystems.

The notochord in Atlantic salmon (Salmo salar L.) undergoes profound morphological and mechanical changes during development.

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Kryvi, Harald; Rusten, Iselin; Fjelldal, Per Gunnar; Nordvik, Kari; Totland, Geir K; Karlsen, Tine; Wiig, Helge; Long, John H

2017-11-01

We present the development of the notochord of the Atlantic salmon (Salmo salar L.), from early embryo to sexually mature fish. Over the salmon's lifespan, profound morphological changes occur. Cells and gross structures of the notochord reorganize twice. In the embryo, the volume of the notochord is dominated by large, vacuolated chordocytes; each cell can be modeled as a hydrostat organized into a larger cellular-hydrostat network, structurally bound together with desmosomes. After the embryo hatches and grows into a fry, vacuolated chordocytes disappear, replaced by extracellular lacunae. The formation of mineralized, segmental chordacentra stiffens the notochord and creates intervertebral joints, where tissue strain during lateral bending is now focused. As development proceeds towards the parr stage, a process of devacuolization and intracellular filament accumulation occur, forming highly dense, non-vacuolated chordocytes. As extracellular lacunae enlarge, they are enclosed by dense filamentous chordocytes that form transverse intervertebral septa, which are connected to the intervertebral ligaments, and a longitudinal notochordal strand. In the vertebral column of pelagic adults, large vacuolated chordocytes reappear; cells of this secondary population have a volume up to 19 000 times larger than the primary vacuolated chordocytes of the early notochord. In adults the lacunae have diminished in relative size. Hydrostatic pressure within the notochord increases significantly during growth, from 525 Pa in the alevins to 11 500 Pa in adults, at a rate of increase with total body length greater than that expected by static stress similarity. Pressure and morphometric measurements were combined to estimate the stress in the extracellular material of the notochordal sheath and intervertebral ligaments and the flexural stiffness of the axial skeleton. The functional significance of the morphological changes in the axial skeleton is discussed in relation to the

Tissue distribution and elimination of deoxynivalenol and ochratoxin A in dietary-exposed Atlantic salmon (Salmo salar).

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Bernhoft, Aksel; Høgåsen, Helga R; Rosenlund, Grethe; Ivanova, Lada; Berntssen, Marc H G; Alexander, Jan; Eriksen, Gunnar Sundstøl; Fæste, Christiane Kruse

2017-07-01

Post-smolt Atlantic salmon (Salmo salar) were fed standard feed with added 2 or 6 mg kg -1 pure deoxynivalenol (DON), 0.8 or 2.4 mg kg -1 pure ochratoxin A (OTA), or no added toxins for up to 8 weeks. The experiments were performed in duplicate tanks with 25 fish each per diet group, and the feed was given for three 2-h periods per day. After 3, 6 and 8 weeks, 10 fish from each diet group were sampled. In the following hours after the last feeding at 8 weeks, toxin elimination was studied by sampling three fish per diet group at five time points. Analysis of DON and OTA in fish tissues and plasma was conducted by liquid chromatography-mass spectrometry and high-pressure liquid chromatography with fluorescence detection, respectively. DON was distributed to the liver, kidney, plasma, muscle, skin and brain, and the concentrations in liver and muscle increased significantly from 3 to 8 weeks of exposure to the high-DON diet. After the last feeding at 8 weeks, DON concentration in liver reached a maximum at 1 h and decreased thereafter with a half-life (t 1/2 ) of 6.2 h. DON concentration in muscle reached a maximum at 6 h and was then eliminated with a t 1/2  = 16.5 h. OTA was mainly found in liver and kidney, and the concentration in liver decreased significantly from 3 to 8 weeks in the high-OTA group. OTA was eliminated faster than DON from various tissues. By using Norwegian food consumption data and kinetic findings in this study, we predicted the human exposure to DON and OTA from fish products through carryover from the feed. Following a comparison with tolerable daily intakes, we found the risk to human health from the consumption of salmon-fed diets containing maximum recommended levels of these toxins to be negligible.

Effective freezing rate for semen cryopreservation in endangered Mediterranean brown trout (Salmo trutta macrostigma) inhabiting the Biferno river (South Italy).

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Iaffaldano, Nicolaia; Di Iorio, Michele; Manchisi, Angelo; Esposito, Stefano; Gibertoni, Pier Paolo

2016-10-01

This study was designed to determine: (i) the in vitro effects of different freezing rates on post-thaw semen quality of Mediterranean brown trout (Salmo trutta macrostigma) from the Biferno river; and (ii) the in vivo fertilization and hatching percentage of freezing rate giving rise to the best post-thaw semen quality. Pooled semen samples were diluted 1:3 (v:v) in a freezing extender composed of 300 mM glucose, 10% egg yolk and 10% dimethyl sulfoxide (DMSO). The extended semen was packaged in 0.25 ml plastic straws and frozen at different heights above the liquid nitrogen surface (1, 5 or 10 cm) for 10 min to give three different freezing rates. Semen samples were thawed at 30°C for 10 s. The variables assessed after thawing were sperm motility, duration of motility and viability. Our results clearly indicate a significant effect of freezing rate on post-thaw semen quality. Semen frozen 5 cm above the liquid nitrogen surface showed the best quality after freezing/thawing. Based on these in vitro data, 2 groups of 200 eggs were fertilized with fresh semen or semen frozen 5 cm above the liquid nitrogen surface. Fertilization and hatching rates recorded for eggs fertilized with frozen semen were significantly lower (25.4% and 22.5%, respectively) than the ones obtained using fresh semen (87.8% and 75.5%, respectively). An effective freezing protocol will allow for the creation of a sperm cryobank to recover the original population of Mediterranean brown trout in the Biferno river.

Effects of algal-produced neurotoxins on metabolic activity in telencephalon, optic tectum and cerebellum of Atlantic salmon (Salmo salar)

International Nuclear Information System (INIS)

Bakke, Marit Jorgensen; Horsberg, Tor Einar

2007-01-01

Neurotoxins from algal blooms have been reported to cause mortality in a variety of species, including sea birds, sea mammals and fish. Farmed fish cannot escape harmful algal blooms and their potential toxins, thus they are more vulnerable for exposure than wild stocks. Sublethal doses of the toxins are likely to affect fish behaviour and may impair cognitive abilities. In the present study, changes in the metabolic activity in different parts of the Atlantic salmon (Salmo salar) brain involved in central integration and cognition were investigated after exposure to sublethal doses of three algal-produced neurotoxins; saxitoxin (STX), brevetoxin (BTX) and domoic acid (DA). Fish were randomly selected to four groups for i.p. injection of saline (control) or one of the neurotoxins STX (10 μg STX/kg bw), BTX (68 μg BTX/kg bw) or DA (6 mg DA/kg bw). In addition, 14 C-2-deoxyglucose was i.m. injected to measure brain metabolic activity by autoradiography. The three regions investigated were telencephalon (Tel), optic tectum (OT) and cerebellum (Ce). There were no differences in the metabolic activity after STX and BTX exposure compared to the control in these regions. However, a clear increase was observed after DA exposure. When the subregions with the highest metabolic rate were pseudocoloured in the three brain regions, the three toxins caused distinct differences in the respective patterns of metabolic activation. Fish exposed to STX displayed similar patterns as the control fish, whereas fish exposed to BTX and DA showed highest metabolic activity in subregions different from the control group. All three neurotoxins affected subregions that are believed to be involved in cognitive abilities in fish

Effects of temperature on feed intake and plasma chemistry after exhaustive exercise in triploid brown trout (Salmo trutta L).

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Preston, Andrew C; Taylor, John F; Fjelldal, Per Gunnar; Hansen, Tom; Migaud, Hervé

2017-04-01

The physiological effect of temperature on feed intake and haematological parameters after exhaustive swimming in diploid and triploid brown trout (Salmo trutta) was investigated. Trout were exposed to an incremental temperature challenge (2 °C/day) from ambient (6 °C) to either 10 or 19 °C. Feed intake profiles did not differ between ploidy at 10 °C; however, triploids had a significantly higher total feed intake at 19 °C. After 24 days, each temperature-ploidy group was exposed to exhaustive swimming for 10 min. The haematological response differed between ploidy, with the magnitude of the response affected by temperature and ploidy. Post-exercise, acid-base and ionic differences were observed. Plasma lactate increased significantly from rest for both temperature and ploidy groups, but glucose increased significantly at higher temperature. Post-exercise, triploids at 19 °C had significantly higher osmolality and cholesterol than diploids, but differences were resumed within 4 h. Elevated alkaline phosphatase (ALP) and aspartate aminotransferase (AST) in fish at higher temperature suggested greater tissue damage; however, both ploidy responded similarly. Despite no significant differences in deformity prevalence, the type and location of deformities observed differed between ploidy (decreased intervertebral space with higher prevalence in tail area and fin regions for diploids, while vertebral compression, fusion in cranial and caudal trunks for triploids). These results suggest triploids have greater appetite than diploids at elevated temperature and that triploids suffer similar blood disturbances after exercise as diploids. These findings have implications for the management of freshwater ecosystems and suggest that stocking triploid brown trout may offer an alternative to diploid brown trout.

Assessing hydrodynamic space use of brown trout, Salmo trutta, in a complex flow environment: a return to first principles.

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Kerr, James R; Manes, Costantino; Kemp, Paul S

2016-11-01

It is commonly assumed that stream-dwelling fish should select positions where they can reduce energetic costs relative to benefits gained and enhance fitness. However, the selection of appropriate hydrodynamic metrics that predict space use is the subject of recent debate and a cause of controversy. This is for three reasons: (1) flow characteristics are often oversimplified, (2) confounding variables are not always controlled and (3) there is limited understanding of the explanatory mechanisms that underpin the biophysical interactions between fish and their hydrodynamic environment. This study investigated the space use of brown trout, Salmo trutta, in a complex hydrodynamic flow field created using an array of different sized vertically oriented cylinders in a large open-channel flume in which confounding variables were controlled. A hydrodynamic drag function (D) based on single-point time-averaged velocity statistics that incorporates the influence of turbulent fluctuations was used to infer the energetic cost of steady swimming. Novel hydrodynamic preference curves were developed and used to assess the appropriateness of D as a descriptor of space use compared with other commonly used metrics. Zones in which performance-enhancing swimming behaviours (e.g. Kármán gaiting, entraining and bow riding) that enable fish to hold position while reducing energetic costs (termed 'specialised behaviours') were identified and occupancy was recorded. We demonstrate that energy conservation strategies play a key role in space use in an energetically taxing environment with the majority of trout groups choosing to frequently occupy areas in which specialised behaviours may be adopted or by selecting low-drag regions. © 2016. Published by The Company of Biologists Ltd.

Evaluation of the net energy value of glucose (cerelose) and maize starch in diets for rainbow trout (Salmo gairdneri).

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Hilton, J W; Atkinson, J L; Slinger, S J

1987-11-01

1. Quadruplicate groups of rainbow trout (Salmo gairdneri) (mean body-weight 24.9 g) were reared on six dietary treatments (practical-type diets) in a modified paired-feeding experiment for 12 weeks at 15 degrees to determine the net energy (NE) value of starch and glucose to rainbow trout. 2. Three test diets were prepared to contain (g/kg): 0 supplemented carbohydrate (diet 1), 250 maize starch (diet 2) and 250 glucose (diet 3) and were given ad lib. to the trout with the feeding rate of the glucose- and starch-fed groups being monitored after each feeding. The remaining three treatments involved controlled feeding of the trout with diet 1 at 75% of the feed intake of trout reared on diets 2 and 3, so as to provide the same levels of protein and lipids without carbohydrate, and with diet 2 at 100% of the feed intake of trout reared on diet 3. 3. The difference in the final carcass energy of the ad lib.-fed group and the respective controlled-fed group divided by the amount of dietary glucose or starch energy consumed by the trout is the NE value for that carbohydrate. 4. The determined NE value of glucose was 3.99 kJ/g and starch 2.17 kJ/g, which is 24.6 and 12.6% respectively of the gross energy values of these carbohydrates in rainbow trout. 5. The results indicate that digestible energy and calculated metabolizable energy values for carbohydrates in rainbow trout overestimate the utilizable energy content of the diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Coping with unpredictability: dopaminergic and neurotrophic responses to omission of expected reward in Atlantic salmon (Salmo salar L..

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Marco A Vindas

Full Text Available Comparative studies are imperative for understanding the evolution of adaptive neurobiological processes such as neural plasticity, cognition, and emotion. Previously we have reported that prolonged omission of expected rewards (OER, or 'frustrative nonreward' causes increased aggression in Atlantic salmon (Salmo salar. Here we report changes in brain monoaminergic activity and relative abundance of brain derived neurotrophic factor (BDNF and dopamine receptor mRNA transcripts in the same paradigm. Groups of fish were initially conditioned to associate a flashing light with feeding. Subsequently, the expected food reward was delayed for 30 minutes during two out of three meals per day in the OER treatment, while the previously established routine was maintained in control groups. After 8 days there was no effect of OER on baseline brain stem serotonin (5-HT or dopamine (DA activity. Subsequent exposure to acute confinement stress led to increased plasma cortisol and elevated turnover of brain stem DA and 5-HT in all animals. The DA response was potentiated and DA receptor 1 (D1 mRNA abundance was reduced in the OER-exposed fish, indicating a sensitization of the DA system. In addition OER suppressed abundance of BDNF in the telencephalon of non-stressed fish. Regardless of OER treatment, a strong positive correlation between BDNF and D1 mRNA abundance was seen in non-stressed fish. This correlation was disrupted by acute stress, and replaced by a negative correlation between BDNF abundance and plasma cortisol concentration. These observations indicate a conserved link between DA, neurotrophin regulation, and corticosteroid-signaling pathways. The results also emphasize how fish models can be important tools in the study of neural plasticity and responsiveness to environmental unpredictability.

Developmental Hypoxia Has Negligible Effects on Long-Term Hypoxia Tolerance and Aerobic Metabolism of Atlantic Salmon (Salmo salar).

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Wood, Andrew T; Clark, Timothy D; Andrewartha, Sarah J; Elliott, Nicholas G; Frappell, Peter B

Exposure to developmental hypoxia can have long-term impacts on the physiological performance of fish because of irreversible plasticity. Wild and captive-reared Atlantic salmon (Salmo salar) can be exposed to hypoxic conditions during development and continue to experience fluctuating oxygen levels as juveniles and adults. Here, we examine whether developmental hypoxia impacts subsequent hypoxia tolerance and aerobic performance of Atlantic salmon. Individuals at 8°C were exposed to 50% (hypoxia) or 100% (normoxia) dissolved oxygen (DO) saturation (as percent of air saturation) from fertilization for ∼100 d (800 degree days) and then raised in normoxic conditions for a further 15 mo. At 18 mo after fertilization, aerobic scope was calculated in normoxia (100% DO) and acute (18 h) hypoxia (50% DO) from the difference between the minimum and maximum oxygen consumption rates ([Formula: see text] and [Formula: see text], respectively) at 10°C. Hypoxia tolerance was determined as the DO at which loss of equilibrium (LOE) occurred in a constantly decreasing DO environment. There was no difference in [Formula: see text], [Formula: see text], or aerobic scope between fish raised in hypoxia or normoxia. There was some evidence that hypoxia tolerance was lower (higher DO at LOE) in hypoxia-raised fish compared with those raised in normoxia, but the magnitude of the effect was small (12.52% DO vs. 11.73% DO at LOE). Acute hypoxia significantly reduced aerobic scope by reducing [Formula: see text], while [Formula: see text] remained unchanged. Interestingly, acute hypoxia uncovered individual-level relationships between DO at LOE and [Formula: see text], [Formula: see text], and aerobic scope. We discuss our findings in the context of developmental trajectories and the role of aerobic performance in hypoxia tolerance.

Altitudinal and thermal gradients of hepatic Cyp1A gene expression in natural populations of Salmo trutta from high mountain lakes and their correlation with organohalogen loads

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Jarque, Sergio; Gallego, Eva [Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, 08034-Barcelona, Catalonia (Spain); Bartrons, Mireia; Catalan, Jordi [Center for Advanced Studies of Blanes (CEAB-CSIC), Acces Cala St. Francesc 14, 17300-Blanes, Catalonia (Spain); Grimalt, Joan O. [Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, 08034-Barcelona, Catalonia (Spain); Pina, Benjamin, E-mail: bpcbmc@cid.csic.e [Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, 08034-Barcelona, Catalonia (Spain)

2010-05-15

The biomarker of xenobiotic exposure cytochrome p450A1 (Cyp1A) was used to analyze the biological response to chemical pollution in Salmo trutta (brown trout) from nine high mountain European lakes in Norway, Tatras, Tyrol, and central Pyrenees. Hepatic Cyp1A mRNA levels correlated both with the reciprocal of absolute annual average air temperatures of the sampled lakes and with muscle concentrations of several hydrophobic organohalogen compounds (OC), including chlorinated polychlorobiphenyls (PCB), DDE, and DDT. The correlation between Cyp1A expression and OC content was observed across the whole temperature range (between -0.7 deg. C and +6.2 deg. C), but also in the absence of any thermal gradient. We concluded that airborne pollutants accumulate in high mountain lake fish at concentrations high enough to increase Cyp1A expression, among other possible effects. As geographical distribution of semi-volatile OC is strongly influenced by air temperatures, future climate modifications will potentially enhance their physiological effects in lake ecosystems. - Altitudinal gradients of hepatic Cyp1A gene expression in mountain trout correlate with geographic and individual organohalogen distribution.

Accuracy of Assignment of Atlantic Salmon (Salmo salar L.) to Rivers and Regions in Scotland and Northeast England Based on Single Nucleotide Polymorphism (SNP) Markers

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Gilbey, John; Cauwelier, Eef; Coulson, Mark W.; Stradmeyer, Lee; Sampayo, James N.; Armstrong, Anja; Verspoor, Eric; Corrigan, Laura; Shelley, Jonathan; Middlemas, Stuart

2016-01-01

Understanding the habitat use patterns of migratory fish, such as Atlantic salmon (Salmo salar L.), and the natural and anthropogenic impacts on them, is aided by the ability to identify individuals to their stock of origin. Presented here are the results of an analysis of informative single nucleotide polymorphic (SNP) markers for detecting genetic structuring in Atlantic salmon in Scotland and NE England and their ability to allow accurate genetic stock identification. 3,787 fish from 147 sites covering 27 rivers were screened at 5,568 SNP markers. In order to identify a cost-effective subset of SNPs, they were ranked according to their ability to differentiate between fish from different rivers. A panel of 288 SNPs was used to examine both individual assignments and mixed stock fisheries and eighteen assignment units were defined. The results improved greatly on previously available methods and, for the first time, fish caught in the marine environment can be confidently assigned to geographically coherent units within Scotland and NE England, including individual rivers. As such, this SNP panel has the potential to aid understanding of the various influences acting upon Atlantic salmon on their marine migrations, be they natural environmental variations and/or anthropogenic impacts, such as mixed stock fisheries and interactions with marine power generation installations. PMID:27723810

Carbon monoxide stunning of Atlantic salmon (Salmo salar L.) modifies rigor mortis and sensory traits as revealed by NIRS and other instruments.

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Concollato, Anna; Parisi, Giuliana; Masoero, Giorgio; Romvàri, Robert; Olsen, Rolf-Erik; Dalle Zotte, Antonella

2016-08-01

Methods of stunning used in salmon slaughter are still the subject of research. Fish quality can be influenced by pre-, ante- and post-mortem conditions, including handling before slaughter, slaughter methods and storage conditions. Carbon monoxide (CO) is known to improve colour stability in red muscle and to reduce microbial growth and lipid oxidation in live fish exposed to CO. Quality differences in Atlantic salmon, Salmo salar L., stunned by CO or percussion, were evaluated and compared by different techniques [near infrared reflectance spectroscopy (NIRS), electronic nose (EN), electronic tongue (ET)] and sensory analysis. Thawed samples, freeze-dried preparates and NIRS devices proved to be the most efficient combinations for discriminating the treatments applied to salmon, i.e. first the stunning methods adopted, then the back-prediction of the maximum time to reach rigor mortis and finally to correlate some sensory attributes. A trained panel found significant differences between control and CO-stunned salmon: reduced tactile crumbliness, reduced odour and aroma intensities, and reduced tenderness of CO-treated fillets. CO stunning reduced radiation absorbance in spectra of thawed and freeze-dried fillets, but not fillet samples stored in ethanol, where it may have interacted with myoglobin and myosin. The good results in a rapid discrimination of thawed samples detected by NIRS suggest suitable applications in the fish industry. CO treatment could mitigate sensory perception, but consumer tests are needed to confirm our findings. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Encystment of parasitic freshwater pearl mussel (Margaritifera margaritifera) larvae coincides with increased metabolic rate and haematocrit in juvenile brown trout (Salmo trutta).

Science.gov (United States)

Filipsson, Karl; Brijs, Jeroen; Näslund, Joacim; Wengström, Niklas; Adamsson, Marie; Závorka, Libor; Österling, E Martin; Höjesjö, Johan

2017-04-01

Gill parasites on fish are likely to negatively influence their host by inhibiting respiration, oxygen transport capacity and overall fitness. The glochidia larvae of the endangered freshwater pearl mussel (FPM, Margaritifera margaritifera (Linnaeus, 1758)) are obligate parasites on the gills of juvenile salmonid fish. We investigated the effects of FPM glochidia encystment on the metabolism and haematology of brown trout (Salmo trutta Linnaeus, 1758). Specifically, we measured whole-animal oxygen uptake rates at rest and following an exhaustive exercise protocol using intermittent flow-through respirometry, as well as haematocrit, in infested and uninfested trout. Glochidia encystment significantly affected whole-animal metabolic rate, as infested trout exhibited higher standard and maximum metabolic rates. Furthermore, glochidia-infested trout also had elevated levels of haematocrit. The combination of an increased metabolism and haematocrit in infested fish indicates that glochidia encystment has a physiological effect on the trout, perhaps as a compensatory response to the potential respiratory stress caused by the glochidia. When relating glochidia load to metabolism and haematocrit, fish with low numbers of encysted glochidia were the ones with particularly elevated metabolism and haematocrit. Standard metabolic rate decreased with substantial glochidia loads towards levels similar to those of uninfested fish. This suggests that initial effects visible at low levels of encystment may be countered by additional physiological effects at high loads, e.g. potential changes in energy utilization, and also that high numbers of glochidia may restrict oxygen uptake by the gills.

A comparative study of diploid versus triploid Atlantic salmon (Salmo salar L.). The effects of rearing temperatures (5, 10 and 15°C) on raw material characteristics and storage quality.

Science.gov (United States)

Lerfall, Jørgen; Hasli, Pål Rune; Skare, Even Flønes; Olsen, Rolf Erik; Rotabakk, Bjørn Tore; Roth, Bjørn; Slinde, Erik; Egelandsdal, Bjørg

2017-06-15

Several major market operators argue that the current level of knowledge about quality is too scant to justify a switch to a large-scale production of triploid salmon. The aim of the present study was, therefore, to elucidate how rearing conditions (5, 10 and 15°C) affect the flesh quality of triploid Atlantic salmon (Salmo salar L., 1.6±0.3kg). As a reference, diploid salmon kept under equal conditions and with equal genetics were used. The main design discriminant was the holding temperature; increased temperature gave increased blood lactate, rigor index (I r ), drip loss (DL), content of astaxanthin and intensity of redness, but reduced muscle pH, cathepsin activity and fillet lightness. Salmon kept at 10°C grew the fastest. It is concluded that ploidy gave less variation than temperature. Triploids were characterized by lower blood haematocrit (Hct) and I r , higher DL and collagenase activity, and on average, paler and less yellowish fillets. Copyright © 2017 Elsevier Ltd. All rights reserved.

HPLC Quantification of astaxanthin and canthaxanthin in Salmonidae eggs.

Science.gov (United States)

Tzanova, Milena; Argirova, Mariana; Atanasov, Vasil

2017-04-01

Astaxanthin and canthaxanthin are naturally occurring antioxidants referred to as xanthophylls. They are used as food additives in fish farms to improve the organoleptic qualities of salmonid products and to prevent reproductive diseases. This study reports the development and single-laboratory validation of a rapid method for quantification of astaxanthin and canthaxanthin in eggs of rainbow trout (Oncorhynchus mykiss) and brook trout (Salvelinus fontinalis М.). An advantage of the proposed method is the perfect combination of selective extraction of the xanthophylls and analysis of the extract by high-performance liquid chromatography and photodiode array detection. The method validation was carried out in terms of linearity, accuracy, precision, recovery and limits of detection and quantification. The method was applied for simultaneous quantification of the two xanthophylls in eggs of rainbow trout and brook trout after their selective extraction. The results show that astaxanthin accumulations in salmonid fish eggs are larger than those of canthaxanthin. As the levels of these two xanthophylls affect fish fertility, this method can be used to improve the nutritional quality and to minimize the occurrence of the M74 syndrome in fish populations. Copyright © 2016 John Wiley & Sons, Ltd.

TELEOSTEI; CYPRINIDAE

African Journals Online (AJOL)

these fISh (Love 1970), but the effects of maintaining fISh in laboratory aquaria on their haematology per se have not yet been investigated and laboratory data are usually thought to apply to wild fish as well. Newly caught, exhausted fish cannot be used for the determination of certain physiological parameters (Love 1970) ...

Teleostei: Sparidae

African Journals Online (AJOL)

ponent of the fish community to receive attention. In order to assess the importance of the availability of various benthic ... Particular attention has also been paid to resource ..... has permitted an analysis of how selective R. sorbo is for prey.

TELEOSTEI: SPARIDAE

African Journals Online (AJOL)

There was no indication of sex-reversal, the steenbras remaining permanently ...... However, with ages greater than six exact determination ...... chances of inbreeding by self-fertilization and the possible crosses and lowering of the effective.

TELEOSTEI; MUGILIDAE

African Journals Online (AJOL)

The different spermatogenic cells were measured under oil immersion (1 000 X). Both bright field and ... which runs along the entire length of the testes, as in Eucalia inconstans (Ruby & McMillan. 1970). The left ..... The vertebrate body. Ed. 4.

Teleostei, Apogonidae

African Journals Online (AJOL)

1992-01-13

Jan 13, 1992 ... It remains to be seen if lhis social system is usual in this species. how olher aspects of ... Crewe 1990b), also has a queen caste, but it is not known how similar the .... several localities in the Western Indian Ocean. The counts.

Teleostei: Sparidae

African Journals Online (AJOL)

1991-05-02

May 2, 1991 ... P. grande is primarily herbivorous, feeding selectively on rhodophytes found on ... (1981) also states that P. grande attains sexual maturity between 40-45 cm ...... 31 these fish. For these reasons it is important that attention be.

TELEOSTEI: MUGILIDAE

African Journals Online (AJOL)

The breeding cycle of male Liza dumerili was studied in the Swartkops Estuary using a visual index, a gonosomatic index and a histological index. Histological studies were superior to any other means of establishing the breeding cycle in detail. Male fISh were in the inactive or non-breeding state during the winter months.

TELEOSTEI: MUGILIDAE

African Journals Online (AJOL)

Active. spermatocytogenesis, meiosis and spermiogenesis All testis lobules filled with cysts of primary and secondary spermato- cytes and spermatids. Sperm content of testis and main sperm duct varying from few sperm present to packed with sperm. Stage 6: Late spermiogenesis. More than 90% of testis filled with sperm.

TELEOSTEI; CLINIDAE

African Journals Online (AJOL)

richness and abundance of clinids in a group of intertidal rock pools near Muizenberg ... were made of the species, number and age classes of all fish present and their positions and activities. ... dependent variable due to variation in an independent variable (Sokal & Rohlf 1969). Log-. R ep ... Only two other fish species,.

Immunostimulation of Salmo salar L., and its effect on Lepeophtheirus salmonis (Krøyer) P-glycoprotein mRNA expression following subsequent emamectin benzoate exposure.

Science.gov (United States)

Igboeli, O O; Purcell, S L; Wotton, H; Poley, J; Burka, J F; Fast, M D

2013-03-01

Control of sea lice, Lepeophtheirus salmonis, on farmed Atlantic salmon, Salmo salar, relies heavily on chemotherapeutants. However, reduced efficacy of many treatments and need for integrated sea lice management plans require innovative strategies. Resistance to emamectin benzoate (EMB), a major sea lice parasiticide, has been linked with P-glycoprotein (P-gp) expression. We hypothesized that host immunostimulation would complement EMB treatment outcome. Lepeophtheirus salmonis-infected Atlantic salmon were fed immunostimulatory or control feeds. Sea lice were collected for 24-h EMB bioassays 1 and 2 weeks prior to commencement of EMB treatment of the fish. Two weeks after cessation of immunostimulant-treated feed, EMB was administered at 150 μg kg(-1) fish biomass for 7 days. The bioassay revealed stage, gender and immunostimulant-related differences in EMB EC(50) . Sea lice attached to salmon with a history of immunostimulation exhibited significantly greater survival than those on control feeds, despite similar levels of EMB in host tissues. Lepeophtheirus salmonis from salmon with a history of immunostimulation also exhibited higher P-gp mRNA expression as well as greater survivability compared to controls. Administration of immunostimulants prior to EMB treatment caused increased expression of P-gp mRNA which could have consequently caused decreased efficacy of the parasiticide. © 2013 Blackwell Publishing Ltd.

Biopsie et mesure de l'activité Na+/K+ ATPasique branchiale : validité et impact sur le développement du smolt de saumon Atlantique (Salmo salar L.

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SIEGLER L.

1996-01-01

Full Text Available Une biopsie de fragment de tissu branchial a été effectuée, durant toute la période de smoltification, sur des juvéniles de saumons Atlantique (Salmo salar élevés en pisciculture. Le microdosage de l'activité de la Na+/K+ ATPase branchiale, effectué sur ce fragment de tissu, a été comparé au macrodosage obtenu à partir des branchies entières. Aucune mortalité n'a été observée chez les saumons biopsies dont le taux de croissance (linéaire et pondérale est resté identique à celui des poissons témoins. La bonne correspondance des cinétiques de l'activité enzymatique obtenues par les deux méthodes valide la technique de microdosage et confirme l'absence d'influence sur le développement physiologique ultérieur du smolt biopsie. Nos résultats montrent les modifications envisageables pour améliorer la sensibilité de la méthode. Cette technique est très prometteuse pour l'analyse des populations naturelles

Sensitivity and toxic mode of action of dietary organic and inorganic selenium in Atlantic salmon (Salmo salar).

Science.gov (United States)

Berntssen, M H G; Sundal, T K; Olsvik, P A; Amlund, H; Rasinger, J D; Sele, V; Hamre, K; Hillestad, M; Buttle, L; Ørnsrud, R

2017-11-01

Depending on its chemical form, selenium (Se) is a trace element with a narrow range between requirement and toxicity for most vertebrates. Traditional endpoints of Se toxicity include reduced growth, feed intake, and oxidative stress, while more recent finding describe disturbance in fatty acid synthesis as underlying toxic mechanism. To investigate overall metabolic mode of toxic action, with emphasis on lipid metabolism, a wide scope metabolomics pathway profiling was performed on Atlantic salmon (Salmo salar) (572±7g) that were fed organic and inorganic Se fortified diets. Atlantic salmon were fed a low natural background organic Se diet (0.35mg Se kg -1 , wet weight (WW)) fortified with inorganic sodium selenite or organic selenomethionine-yeast (SeMet-yeast) at two levels (∼1-2 or 15mgkg -1 , WW), in triplicate for 3 months. Apparent adverse effects were assessed by growth, feed intake, oxidative stress as production of thiobarbituric acid-reactive substances (TBARS) and levels of tocopherols, as well as an overall metabolomic pathway assessment. Fish fed 15mgkg -1 selenite, but not 15mgkg -1 SeMet-yeast, showed reduced feed intake, reduced growth, increased liver TBARS and reduced liver tocopherol. Main metabolic pathways significantly affected by 15mgkg -1 selenite, and to a lesser extent 15mgkg -1 SeMet-yeast, were lipid catabolism, endocannabinoids synthesis, and oxidant/glutathione metabolism. Disturbance in lipid metabolism was reflected by depressed levels of free fatty acids, monoacylglycerols and diacylglycerols as well as endocannabinoids. Specific for selenite was the significant reduction of metabolites in the S-Adenosylmethionine (SAM) pathway, indicating a use of methyl donors that could be allied with excess Se excretion. Dietary Se levels to respectively 1.1 and 2.1mgkg -1 selenite and SeMet-yeast did not affect any of the above mentioned parameters. Apparent toxic mechanisms at higher Se levels (15mgkg -1 ) included oxidative stress and

Commercial trials using emamectin benzoate to control sea lice Lepeophtheirus salmonis infestations in Atlantic salmon Salmo salar.

Science.gov (United States)

Stone, J; Sutherland, I H; Sommerville, C; Richards, R H; Varma, K J

2000-06-19

Two trials were conducted at commercial salmon farms to evaluate the efficacy of emamectin benzoate (Slice, 0.2% aquaculture pre-mix, Schering-Plough Animal Health) as a treatment for sea lice Lepeophtheirus salmonis (Krøyer) and Caligus elongatus Nordmann infestations in Atlantic salmon Salmo salar L. Trials were carried out in 15 m2 commercial sea pens, at temperatures of 5.5 to 7.5 degrees C and 10.8 to 13.8 degrees C. Each pen was stocked with 14,000 to 17,500 fish with mean weights of 0.44 to 0.74 and 1.33 to 1.83 kg. Fish were naturally infested with sea lice at the start of each trial. At Day -1, samples of 10 or 15 fish were taken from each pen to determine pre-treatment numbers of lice. Emamectin benzoate was administered in feed, to 4 replicate pens, at a dose of 50 micrograms kg-1 biomass d-1 for 7 consecutive days (Days 0 to 6). Sea lice were counted again, between Days 7 and 77, and comparisons made with untreated control fish. Despite adverse weather conditions, wide variations in fish weights and exposure to new infestations, treatment was effective against chalimus and motile stages of L. salmonis. In the autumn trial, efficacy at Day 27 was 89%, and lice numbers remained lower on treated fish than on control fish 64 d from the start of treatment. In the winter trial, reductions in lice numbers at low temperatures were slower but good efficacy was achieved by Day 35. Although control fish had to be treated with hydrogen peroxide at Day 21, fish treated only with emamectin benzoate on Days 0 to 6 still had 89% fewer lice than control fish at Day 35. There were very few C. elongatus present, but at the end of both trials numbers were lower on treated fish. No adverse effects were associated with treatment of fish with emamectin benzoate.

Comparative analysis of innate immune responses to Streptococcus phocae strains in Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss).

Science.gov (United States)

Salazar, Soraya; Oliver, Cristian; Yáñez, Alejandro J; Avendaño-Herrera, Ruben

2016-04-01

Streptococcus phocae subsp. salmonis is a Gram-positive bacterium that causes mortality only in Atlantic salmon (Salmo salar) farmed in Chile, even when this species is co-cultured with rainbow trout (Oncorhynchus mykiss). This susceptibility could be determined by innate immune response components and their responses to bacterial infection. This fish pathogen shares subspecies status with Streptococcus phocae subsp. phocae isolated from seals. The present study compared innate immune system mechanisms in Atlantic salmon and rainbow trout when challenged with different S. phocae, including two isolates from Atlantic salmon (LM-08-Sp and LM-13-Sp) and two from seal (ATCC 51973(T) and P23). Streptococcus phocae growth was evaluated in the mucus and serum of both species, with rainbow trout samples evidencing inhibitory effects. Lysozyme activity supported this observation, with significantly higher (p trout serum and mucus as compared to Atlantic salmon. No differences were found in phagocytic capacity between fish species when stimulated with ATCC 51973(T) and P23. Against all S. phocae strains, rainbow trout and Atlantic salmon showed up to two-fold increased bactericidal activity, and rainbow trout demonstrated up to three-fold greater reactive oxygen species production in macrophages. In conclusion, the non-specific humoral and cellular barriers of Atlantic salmon were immunologically insufficient against S. phocae subsp. salmonis, thereby facilitating streptococcosis. Moreover, the more robust response of rainbow trout to S. phocae could not be attributed to any specific component of the innate immune system, but was rather the consequence of a combined response by the evaluated components. Copyright © 2016 Elsevier Ltd. All rights reserved.

Experimental Transmission of Infectious Pancreatic Necrosis Virus from the Blue Mussel, Mytilus edulis, to Cohabitating Atlantic Salmon (Salmo salar) Smolts

Science.gov (United States)

Pietrak, Michael R.; Bricknell, Ian

2013-01-01

Integrated multitrophic aquaculture (IMTA) reduces the environmental impacts of commercial aquaculture systems by combining the cultivation of fed species with extractive species. Shellfish play a critical role in IMTA systems by filter-feeding particulate-bound organic nutrients. As bioaccumulating organisms, shellfish may also increase disease risk on farms by serving as reservoirs for important finfish pathogens such as infectious pancreatic necrosis virus (IPNV). The ability of the blue mussel (Mytilus edulis) to bioaccumulate and transmit IPNV to naive Atlantic salmon (Salmo salar) smolts was investigated. To determine the ability of mussels to filter and accumulate viable IPNV, mussels were held in water containing log 4.6 50% tissue culture infective dose(s) (TCID50) of the West Buxton strain of IPNV ml−1. Viable IPNV was detected in the digestive glands (DGs) of IPNV-exposed mussels as early as 2 h postexposure. The viral load in mussel DG tissue significantly increased with time and reached log 5.35 ± 0.25 TCID50 g of DG tissue−1 after 120 h of exposure. IPNV titers never reached levels that were significantly greater than that in the water. Viable IPNV was detected in mussel feces out to 7 days postdepuration, and the virus persisted in DG tissues for at least 18 days of depuration. To determine whether IPNV can be transmitted from mussels to Atlantic salmon, IPNV-exposed mussels were cohabitated with naive Atlantic salmon smolts. Transmission of IPNV did occur from mussels to smolts at a low frequency. The results demonstrate that a nonenveloped virus, such as IPNV, can accumulate in mussels and be transferred to naive fish. PMID:23872575

Genome evolution in the fish family salmonidae: generation of a brook charr genetic map and comparisons among charrs (Arctic charr and brook charr with rainbow trout

Directory of Open Access Journals (Sweden)

Moghadam Hooman K

2011-07-01

species of charr (genus Salvelinus and a trout (genus Oncorhynchus have identified that linkage group arm arrangements are largely retained among these species. Previous studies have revealed that up to 7 regions of high duplicate marker retention occur between Salmo species (i.e., Atlantic salmon and brown trout and rainbow trout, with 5 of these regions exhibiting higher levels of pseudolinkage. Pseudolinkage was detected in the charr species (i.e., BC-1/21, AC-12/27, AC-6/23, = RT-2p/29q, RT-12p/16p, and RT-27p/31p, respectively consistent with three of the five 'salmonid-specific' pseudolinkage regions. Chromosome arms with the highest number of duplicated markers in rainbow trout are the linkage group arms with the highest retention of duplicated markers in both charr species.

Some quantitative indicators of postovulatory aging and its effect on larval and juvenile development of Atlantic salmon (Salmo salar).

Science.gov (United States)

Mommens, Maren; Storset, Arne; Babiak, Igor

2015-07-01

Modern out-of-season egg production in Atlantic salmon (Salmo salar) increases the risk of postovulatory aging (POA) of oocytes. Postovulatory aging is known to influence oocyte quality in salmonids, but reliable tests for POA are lacking in Atlantic salmon egg production. To address this problem, we have collected oocytes from the same 20 Atlantic salmon females sequentially in approximately 1-week intervals, from the start of ovulation until 28 days postovulation (dpo), to determine the effect of natural retention of matured oocytes in body coelomic cavity on further performance of embryos and juveniles produced from those oocytes. Also, we investigated oocyte water hardening and several coelomic fluid parameters as potential quantitative indicators of POA. Oocyte quality decreased significantly from 22 dpo onward, as inferred from decrease in fertilization success and survival of embryos, alevins, and juveniles and increase in alevin and juvenile deformity rates. The occurrence of head deformities was significantly related to postovulatory age of oocytes. Coelomic fluid pH decreased significantly at 28 dpo and correlated positively with fertilization rates (r = 0.45), normal eyed embryo rates (r = 0.67), and alevin relative survival rates (r = 0.63) and negatively correlated with total alevin deformity rates (r = -0.59). Oocyte weight gain at 60 minutes decreased significantly at 28 dpo and correlated negatively with total alevin deformities and the occurrence of cranial nodules (r = -0.99). Generally, quality of ovulated oocytes remained stable for the first 2 weeks after ovulation. Later on, POA negatively influenced Atlantic salmon embryo, alevin, and juvenile performance. For the first time, we show a long-term effect of POA on salmonid juvenile performance. Standardized pH measurements of coelomic fluid could potentially improve embryo and juvenile production by identifying low-quality oocytes at an early stage during the production. Copyright © 2015

Genetic diversity of contemporary populations of Salmo trutta L. in the basin of the River Neretva, Bosnia and Herzegovina

Directory of Open Access Journals (Sweden)

Belma Kalamujic

2015-11-01

Full Text Available Across its cosmopolitan range, the survival of the local gene pool of wild brown trout, Salmo trutta L., is threatened due to habitat degradation, overexploitation, inadequate stocking and hybridization. In Bosnia and Herzegovina, brown trout reside in both, the Danube and the Adriatic river drainages. The aim of this study was to assess the contemporary genetic diversity of brown trout populations in the Neretva River basin and to detect the populations that could serve as a source of material for future revitalization projects. The control region of mitochondrial genome, LDH gene, 13 nuclear microsatellites as well as GP85 SNP were analyzed in a total of 335 specimens from the main course of the River Neretva and 11 of its tributaries. Sampling locations on tributaries were located in hardly accessible areas so to maximally reduce the possibility of previous stocking. Besides the indigenous Adriatic haplotype, the Danube and the Atlantic mtDNA haplotypes were detected, which clearly indicates that populations of brown trout in the Neretva river basin have been subject to translocation activities and stocking with allochthonous gene pool. The existence of individuals with Adriatic haplotype but microsatellite variants corresponding to the Danube and the Atlantic lineages, as well as the presence of obtusirostris haplotype, characteristic for soft-muzzled trout, clearly prove hybridization events. The frequency of almost 100% of the allele 167 (locus SsoSL417 in indigenous group clearly points to the possibility that this allele is correlated with the Neretva/Adriatic haplotype and could be used as a potential marker of autochthony. Though the gene pool of the Neretva brown trout has been highly compromised, there is still a real genetic basis for the successful revitalization of indigenous genetic resources, if the immediate and urgent actions are taken through joint activities of the government, public and private sectors (fisheries, and

Predation on Atlantic salmon and sea trout during their first days as postsmolts

DEFF Research Database (Denmark)

Dieperink, C.; Bak, B.D.; Pedersen, Lars-Flemming

2002-01-01

Radio-tagged smolts of Atlantic salmon Salmo salar and sea trout Salmo trutta were predated heavily by sea birds after crossing the saline limit in the estuary of the River Skjern, Denmark. Most predation took place within the first 9 h after estuarine entry. The field data do not contradict...

Tissue sterol composition in Atlantic salmon (Salmo salar L.) depends on the dietary cholesterol content and on the dietary phytosterol:cholesterol ratio, but not on the dietary phytosterol content.

Science.gov (United States)

Sissener, Nini H; Rosenlund, Grethe; Stubhaug, Ingunn; Liland, Nina S

2018-03-01

The aim of the study was to investigate how the dietary sterol composition, including cholesterol, phytosterol:cholesterol ratio and phytosterols, affect the absorption, biliary excretion, retention, tissue storage and distribution of cholesterol and individual phytosterols in Atlantic salmon (Salmo salar L.). A feeding trial was conducted at two different temperatures (6 and 12°C), using nine different diets with varying contents of phytosterols, cholesterol and phytosterol:cholesterol ratio. Cholesterol retention values were clearly dependent on dietary cholesterol, and showed that fish fed cholesterol levels phytosterol:cholesterol ratio, but not on the dietary phytosterol content in itself. Campesterol and brassicasterol appeared to be the phytosterols with the highest intestinal absorption in Atlantic salmon. There was a high biliary excretion of campesterol, but not of brassicasterol, which accumulated in tissues and particularly in adipose tissue, with 2-fold-higher retention at 12°C compared with 6°C. Campesterol had the second highest retention of the phytosterols in the fish, but with no difference between the two temperatures. Other phytosterols had very low retention. Although brassicasterol retention decreased with increasing dietary phytosterols, campesterol retention decreased with increasing dietary cholesterol, indicating differences in the uptake mechanisms for these two sterols.

A new specific reference gene based on growth hormone gene (GH1) used for detection and relative quantification of Aquadvantage® GM salmon (Salmo salar L.) in food products.

Science.gov (United States)

Hafsa, Ahmed Ben; Nabi, Nesrine; Zellama, Mohamed Salem; Said, Khaled; Chaouachi, Maher

2016-01-01

Genetic transformation of fish is mainly oriented towards the improvement of growth for the benefit of the aquaculture. Actually, Atlantic salmon (Salmo salar) is the species most transformed to achieve growth rates quite large compared to the wild. To anticipate the presence of contaminations with GM salmon in fish markets and the lack of labeling regulations with a mandatory threshold, the proper methods are needed to test the authenticity of the ingredients. A quantitative real-time polymerase chain reaction (QRT-PCR) method was used in this study. Ct values were obtained and validated using 15 processed food containing salmon. The relative and absolute limits of detection were 0.01% and 0.01 ng/μl of genomic DNA, respectively. Results demonstrate that the developed QRT-PCR method is suitable specifically for identification of S. salar in food ingredients based on the salmon growth hormone gene 1 (GH1). The processes used to develop the specific salmon reference gene case study are intended to serve as a model for performing quantification of Aquadvantage® GM salmon on future genetically modified (GM) fish to be commercialized. Copyright © 2015 Elsevier Ltd. All rights reserved.

A highly redundant BAC library of Atlantic salmon (Salmo salar: an important tool for salmon projects

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Koop Ben F

2005-04-01

Full Text Available Abstract Background As farming of Atlantic salmon is growing as an aquaculture enterprise, the need to identify the genomic mechanisms for specific traits is becoming more important in breeding and management of the animal. Traits of importance might be related to growth, disease resistance, food conversion efficiency, color or taste. To identify genomic regions responsible for specific traits, genomic large insert libraries have previously proven to be of crucial importance. These large insert libraries can be screened using gene or genetic markers in order to identify and map regions of interest. Furthermore, large-scale mapping can utilize highly redundant libraries in genome projects, and hence provide valuable data on the genome structure. Results Here we report the construction and characterization of a highly redundant bacterial artificial chromosome (BAC library constructed from a Norwegian aquaculture strain male of Atlantic salmon (Salmo salar. The library consists of a total number of 305 557 clones, in which approximately 299 000 are recombinants. The average insert size of the library is 188 kbp, representing 18-fold genome coverage. High-density filters each consisting of 18 432 clones spotted in duplicates have been produced for hybridization screening, and are publicly available 1. To characterize the library, 15 expressed sequence tags (ESTs derived overgos and 12 oligo sequences derived from microsatellite markers were used in hybridization screening of the complete BAC library. Secondary hybridizations with individual probes were performed for the clones detected. The BACs positive for the EST probes were fingerprinted and mapped into contigs, yielding an average of 3 contigs for each probe. Clones identified using genomic probes were PCR verified using microsatellite specific primers. Conclusion Identification of genes and genomic regions of interest is greatly aided by the availability of the CHORI-214 Atlantic salmon BAC

Toxicokinetics of tetrabromoethylcyclohexane (TBECH) in juvenile brown trout (Salmo trutta) and effects on plasma sex hormones

International Nuclear Information System (INIS)

Gemmill, Bonnie; Pleskach, Kerri; Peters, Lisa; Palace, Vince; Wautier, Kerry; Park, Brad; Darling, Colin; Rosenberg, Bruno; McCrindle, Robert; Tomy, Gregg T.

2011-01-01

Technical 1,2-dibromo-4-(1,2 dibromoethyl)cyclohexane or tetrabromoethylcyclohexane (TBECH) used primarily as an additive flame retardant in polystyrene foams, contains two diastereoisomers, α- and β- present in equimolar amounts. At temperatures in excess of 125 o C, isomerization to two other isoforms, δ- and γ- is possible. The recent detection of TBECH in the environment and studies suggesting that isomers are androgenic prompted us to examine the toxicokinetics and biochemical effects of one of the isomers, β-, in a controlled laboratory environment. Juvenile brown trout (Salmo trutta) were exposed to three different amounts of the β-isomer (low, medium and high) via the food followed by a period in which they were exposed to unfortified food. A fourth group of fish was exposed to unfortified food for the duration of the experiment. On days 0, 7, 14, 21, 35, 49, 56, 63, 77, 91, 105, and 133, eight fish from each treatment group were euthanized and liver, plasma, lower jaw (i.e., thyroid tissue) and gonad were collected and the remaining tissue ('whole-fish') was retained. β-Isomer content was measured in whole-fish and in liver while estradiol (E2), 11-ketotestosterone (11-KT) and testosterone (T) were measured in plasma. Based on liver and gonad somatic indices, no apparent effects on liver or gonad development in fish from any of the treatment groups were observed. The bioaccumulation of β-isomer was similar in fish from all treatment groups with steady-state occurring before the end of the uptake phase. Depuration of the β-isomer from fish obeyed first order kinetics and there were no statistically significant differences in the depuration half life (t 1/2 ) among the treatment groups: 22.5 ± 10.4 (low), 13.5 ± 5.9 (med) and 13.8 ± 2.2 (high) days. Steady-state biomagnification factors were much smaller than 1 for fish in all treatment groups. Debrominated metabolites were not detected in composite liver or whole-fish extracts and there was no

Toxicokinetics of tetrabromoethylcyclohexane (TBECH) in juvenile brown trout (Salmo trutta) and effects on plasma sex hormones

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Gemmill, Bonnie [Fisheries and Oceans Canada, Arctic Aquatic Research Division, Winnipeg, Manitoba R3T 2N6 (Canada); Department of Environment and Geography, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); Pleskach, Kerri [Fisheries and Oceans Canada, Arctic Aquatic Research Division, Winnipeg, Manitoba R3T 2N6 (Canada); Peters, Lisa [Fisheries and Oceans Canada, Arctic Aquatic Research Division, Winnipeg, Manitoba R3T 2N6 (Canada); Department of Environment and Geography, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); Palace, Vince [Department of Environment and Geography, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); Fisheries and Oceans Canada, Environmental Science Division, Winnipeg, Manitoba R3T 2N6 (Canada); Wautier, Kerry; Park, Brad [Fisheries and Oceans Canada, Environmental Science Division, Winnipeg, Manitoba R3T 2N6 (Canada); Darling, Colin; Rosenberg, Bruno [Fisheries and Oceans Canada, Arctic Aquatic Research Division, Winnipeg, Manitoba R3T 2N6 (Canada); McCrindle, Robert [Wellington Laboratories Incorporated, Research Division, Guelph, ON N1G 3M5 (Canada); Tomy, Gregg T., E-mail: gregg.tomy@dfo-mpo.gc.ca [Fisheries and Oceans Canada, Arctic Aquatic Research Division, Winnipeg, Manitoba R3T 2N6 (Canada); Department of Environment and Geography, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada)

2011-01-25

Technical 1,2-dibromo-4-(1,2 dibromoethyl)cyclohexane or tetrabromoethylcyclohexane (TBECH) used primarily as an additive flame retardant in polystyrene foams, contains two diastereoisomers, {alpha}- and {beta}- present in equimolar amounts. At temperatures in excess of 125 {sup o}C, isomerization to two other isoforms, {delta}- and {gamma}- is possible. The recent detection of TBECH in the environment and studies suggesting that isomers are androgenic prompted us to examine the toxicokinetics and biochemical effects of one of the isomers, {beta}-, in a controlled laboratory environment. Juvenile brown trout (Salmo trutta) were exposed to three different amounts of the {beta}-isomer (low, medium and high) via the food followed by a period in which they were exposed to unfortified food. A fourth group of fish was exposed to unfortified food for the duration of the experiment. On days 0, 7, 14, 21, 35, 49, 56, 63, 77, 91, 105, and 133, eight fish from each treatment group were euthanized and liver, plasma, lower jaw (i.e., thyroid tissue) and gonad were collected and the remaining tissue ('whole-fish') was retained. {beta}-Isomer content was measured in whole-fish and in liver while estradiol (E2), 11-ketotestosterone (11-KT) and testosterone (T) were measured in plasma. Based on liver and gonad somatic indices, no apparent effects on liver or gonad development in fish from any of the treatment groups were observed. The bioaccumulation of {beta}-isomer was similar in fish from all treatment groups with steady-state occurring before the end of the uptake phase. Depuration of the {beta}-isomer from fish obeyed first order kinetics and there were no statistically significant differences in the depuration half life (t{sub 1/2}) among the treatment groups: 22.5 {+-} 10.4 (low), 13.5 {+-} 5.9 (med) and 13.8 {+-} 2.2 (high) days. Steady-state biomagnification factors were much smaller than 1 for fish in all treatment groups. Debrominated metabolites were not

The relative absorption of fatty acids in brown trout (Salmo trutta fed a commercial extruded pellet coated with different lipid sources

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Franco Valfré

2010-01-01

Full Text Available The objective of the present study was to investigate the fatty acid absorption capabilities of brown trout (Salmo trut- ta fed commercial extruded diets. Five commercial extruded pellets, different only in the lipid sources used for fat coat- ing, were tested on juvenile brown trout for 45 days. The trout were reared in fresh water at 14.6 ± 0.4° C and 7.7 ± 0.3 mg/l, temperature and dissolved oxygen, respectively. The tested lipid sources were fish oil, canola oil, oleine oil, swine fat and poultry fat. After the adaptation period faeces were collected by gently stripping from anaesthetized fish. Fatty acid analysis was performed on experimental diets and on collected faeces to evaluate the relative absorption capabilities of the trout digestive system with respect to each detected fatty acid. The use of the relative absorption efficiency (rAE was opted to evaluate the intrinsic capability of each fatty acid to be absorbed. Brown trout showed a specific preferential order of absorption of the fatty acids, preferring shorter over longer chain fatty acids and prefer- ring the more unsaturated to the more saturated fatty acids. The fatty acid that showed the best relative absorbability was the C18:4n-3 (rAE = 5.14 ± 0.72, which has a fairly short carbon chain, but at the same time a high unsatura- tion level, followed by the C18:3n-3 (rAE = 3.38 ± 0.30. The fatty acid that showed the worst relative absorbability (rAE = 0.21 ± 0.02 was C24:1n-9.

Lack of arterial PO2 downregulation in Atlantic salmon (Salmo salar L.) during long-term normoxia and hyperoxia.

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Kristensen, T; Rosseland, B O; Kiessling, A; Djordevic, B; Massabau, J C

2010-12-01

Regulation of arterial partial pressure of O2 (PaO2) in Atlantic salmon (Salmo salar) was investigated during resting conditions in normoxic and hyperoxic water. Dorsal aorta cannulated adult Atlantic salmon (1.2-1.6 kg, n=8) were exposed to 2 week sequential periods of normoxia [16.7±1.1 kPa (mean±SD)] and hyperoxia (34.1±4.9 kPa) in individual tanks containing seawater (33.7±0.2 ppt) at stable temperature conditions (8.7±0.7°C) and a light regime of L:D=12:12. Tank design and sampling procedures were optimized to provide suitable shelter and current for the fish, and to allow repeated, undisturbed sampling of blood from free-swimming fish. Fish were sampled regularly through the experimental period. PwO2, PaO2, blood ion composition (Na+, K+, Cl-), acid-base status (pH, PCO2, HCO3-), haematocrit and glucose were measured. The most frequently observed PaO2 values were in the range of 60-80% of PwO2, both during normoxia and hyperoxia, and PaO2 values were significantly lower during normoxia than during hyperoxia. Blood pH, PCO2 and HCO3- were significantly elevated during hyperoxia, while, Na+, Cl- and Hct were significantly lower. K+ and glucose showed no significant differences. This study demonstrates a lack PaO2 regulation in Atlantic salmon to low partial pressures, in contrast to previous reports for many aquatic gill breathing animals. Both during normoxia and hyperoxia, PaO2 reflects PwO2, and alterations in external PO2 consequently result in proportional arterial PO2 changes. Physiological adaptation to hyperoxia, as illustrated by changes in several blood parameters, does not include down-regulation of PaO2 in Atlantic salmon. The lack of PaO2 regulation may make Atlantic salmon vulnerable to the oxidative stress caused by increased free radical formation in hyperoxic conditions.

Shifts in the suitable habitat available for brown trout (Salmo trutta L.) under short-term climate change scenarios.

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Muñoz-Mas, R; Lopez-Nicolas, A; Martínez-Capel, F; Pulido-Velazquez, M

2016-02-15

The impact of climate change on the habitat suitability for large brown trout (Salmo trutta L.) was studied in a segment of the Cabriel River (Iberian Peninsula). The future flow and water temperature patterns were simulated at a daily time step with M5 models' trees (NSE of 0.78 and 0.97 respectively) for two short-term scenarios (2011-2040) under the representative concentration pathways (RCP 4.5 and 8.5). An ensemble of five strongly regularized machine learning techniques (generalized additive models, multilayer perceptron ensembles, random forests, support vector machines and fuzzy rule base systems) was used to model the microhabitat suitability (depth, velocity and substrate) during summertime and to evaluate several flows simulated with River2D©. The simulated flow rate and water temperature were combined with the microhabitat assessment to infer bivariate habitat duration curves (BHDCs) under historical conditions and climate change scenarios using either the weighted usable area (WUA) or the Boolean-based suitable area (SA). The forecasts for both scenarios jointly predicted a significant reduction in the flow rate and an increase in water temperature (mean rate of change of ca. -25% and +4% respectively). The five techniques converged on the modelled suitability and habitat preferences; large brown trout selected relatively high flow velocity, large depth and coarse substrate. However, the model developed with support vector machines presented a significantly trimmed output range (max.: 0.38), and thus its predictions were banned from the WUA-based analyses. The BHDCs based on the WUA and the SA broadly matched, indicating an increase in the number of days with less suitable habitat available (WUA and SA) and/or with higher water temperature (trout will endure impoverished environmental conditions ca. 82% of the days). Finally, our results suggested the potential extirpation of the species from the study site during short time spans. Copyright © 2015

Molecular and cellular effects of chemicals disrupting steroidogenesis during early ovarian development of brown trout (Salmo trutta fario).

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a Marca Pereira, M L; Eppler, E; Thorpe, K L; Wheeler, J R; Burkhardt-Holm, P

2014-02-01

A range of chemicals found in the aquatic environment have the potential to influence endocrine function and affect sexual development by mimicking or antagonizing the effects of hormones, or by altering the synthesis and metabolism of hormones. The aim of this study was to evaluate whether the effects of chemicals interfering with sex hormone synthesis may affect the regulation of early ovarian development via the modulation of sex steroid and insulin-like growth factor (IGF) systems. To this end, ex vivo ovary cultures of juvenile brown trout (Salmo trutta fario) were exposed for 2 days to either 1,4,6-androstatriene-3,17-dione (ATD, a specific aromatase inhibitor), prochloraz (an imidazole fungicide), or tributyltin (TBT, a persistent organic pollutant). Further, juvenile female brown trout were exposed in vivo for 2 days to prochloraz or TBT. The ex vivo and in vivo ovarian gene expression of the aromatase (CYP19), responsible for estrogen production, and of IGF1 and 2 were compared. Moreover, 17β-estradiol (E2) and testosterone (T) production from ex vivo ovary cultures was assessed. Ex vivo exposure to ATD inhibited ovarian E2 synthesis, while T levels accumulated. However, ATD did not affect ex vivo expression of cyp19, igf1, or igf2. Ex vivo exposure to prochloraz inhibited ovarian E2 production, but did not affect T levels. Further prochloraz up-regulated igf1 expression in both ex vivo and in vivo exposures. TBT exposure did not modify ex vivo synthesis of either E2 or T. However, in vivo exposure to TBT down-regulated igf2 expression. The results indicate that ovarian inhibition of E2 production in juvenile brown trout might not directly affect cyp19 and igf gene expression. Thus, we suggest that the test chemicals may interfere with both sex steroid and IGF systems in an independent manner, and based on published literature, potentially lead to endocrine dysfunction and altered sexual development. Copyright © 2011 Wiley Periodicals, Inc., A Wiley

Parental genetic diversity of brown trout (Salmo trutta m. fario) brood stock affects offspring susceptibility to whirling disease.

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Eszterbauer, Edit; Forró, Barbara; Tolnai, Zoltán; Guti, Csaba Ferenc; Zsigmond, Gergely; Hoitsy, György; Kallert, Dennis Marc

2015-03-03

Whirling disease, caused by the myxozoan parasite Myxobolus cerebralis, has high economical and ecological importance worldwide. Susceptibility to the disease varies considerably among salmonid species. In brown trout (Salmo trutta) the infection is usually subclinical with low mortality, which increases the risk of parasite dissemination, especially when farm fish are used for stocking natural habitats. The influence of intraspecific genetic differences (especially the level of homozygosity) on susceptibility is unknown. Therefore, we examined the possible correlations between parental genetic diversity and offspring susceptibility of brown trout stocks to whirling disease. Two brown trout brood stocks from a German and a Hungarian fish farm were genetically characterized using microsatellite and lineage-specific genetic markers. The individual inbreeding coefficient f and pairwise relatedness factor r were estimated based on eight microsatellite markers. Brood stock populations were divided into groups according to low and high f and r value estimates and subjected to selective fertilization. The offspring from these separate groups were exposed to M. cerebralis actinospores, and the infection prevalence and intensity was measured and statistically analysed. The analysis of phylogeographic lineage heritage revealed high heterogeneity in the Hungarian brood stock since > 50% of individuals were Atlantic-Danubian hybrids, while only pure Atlantic-descending specimens were detected in the German population. Based on f msat and r msat estimations, classified non-inbred (NIB), inbred (IB) and a group of closely related fish (REL) were created. The susceptibility of their offspring varied considerably. Although there was no significant difference in the prevalence of M. cerebralis infection, the mean intensity of infection differed significantly between NIB and IB groups. In REL and IB groups, a high variability was observed in infection intensity. No external

Surface feeding and aggressive behaviour of diploid and triploid brown trout Salmo trutta during allopatric pair-wise matchings.

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Preston, A C; Taylor, J F; Adams, C E; Migaud, H

2014-09-01

Diploid and triploid brown trout Salmo trutta were acclimated for 6 weeks on two feeding regimes (floating and sinking). Thereafter, aggression and surface feeding response were compared between pairs of all diploid, all triploid and diploid and triploid S. trutta in an experimental stream. In each pair-wise matching, fish of similar size were placed in allopatry and rank was determined by the total number of aggressive interactions recorded. Dominant individuals initiated more aggression than subordinates, spent more time defending a territory and positioned themselves closer to the surface food source (Gammarus pulex), whereas subordinates occupied the peripheries. In cross ploidy trials, diploid S. trutta were more aggressive than triploid, and dominated their sibling when placed in pair-wise matchings. Surface feeding, however, did not differ statistically between ploidy irrespective of feeding regime. Triploids adopted a sneak feeding strategy while diploids expended more time defending a territory. In addition, we also tested whether triploids exhibit a similar social dominance to diploids when placed in allopatry. Although aggression was lower in triploid pairs than in the diploid and triploid pairs, a dominance hierarchy was also observed between individuals of the same ploidy. Dominant triploid fish were more aggressive and consumed more feed items than subordinate individuals. Subordinate fish displayed a darker colour index than dominant fish suggesting increased stress levels. Dominant triploid fish, however, appeared to be more tolerant of subordinate individuals and did not display the same degree of invasive aggression as seen in the diploid and diploid or diploid and triploid matchings. These novel findings suggest that sterile triploid S. trutta feed similarly but are less aggressive than diploid trout. Future studies should determine the habitat choice of triploid S. trutta after release and the interaction between wild fish and triploids during

Evaluation of architectural and histopathological biomarkers in the intestine of brown trout (Salmo trutta Linnaeus, 1758) challenged with environmental pollution.

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Barišić, Josip; Filipović Marijić, Vlatka; Mijošek, Tatjana; Čož-Rakovac, Rozelindra; Dragun, Zrinka; Krasnići, Nesrete; Ivanković, Dušica; Kružlicová, Dáša; Erk, Marijana

2018-06-14

In the present study novel histopathological approach, using fish intestine as a sensitive bioindicator organ of pollution impact in the freshwater ecosystem, was proposed. Histopathological alterations were compared between native brown trout (Salmo trutta Linnaeus, 1758) from the reference (Krka River spring) and pollution impacted location (influence of technological/municipal wastewaters and agricultural runoff near the Town of Knin) of the karst Krka River in Croatia. In brown trout from both locations, severe parasitic infestation with acanthocephalan species Dentitruncus trutae was found, enabling evaluation of acanthocephalan infestation histopathology, which indicated parasite tissue reaction in a form of inflammatory, necrotic and hyperplastic response that extended throughout lamina epithelialis mucosae, lamina propria, and lamina muscularis mucosae. New semi-quantitative histological approach was proposed in order to foresee alterations classified in three reaction patterns: control tissue appearance, moderate (progressive) tissue impairment and severe (regressive and inflammatory) tissue damage. The most frequent progressive alteration was hyperplasia of epithelium on the reference site, whereas the most frequent regressive alterations were atrophy and necrosis seen on the polluted site. Furthermore, histopathological approach was combined with micromorphological and macromorphological assessment as an additional indicator of pollution impact. Among 15 observed intestinal measures, two biomarkers of intestinal tissue damage were indicated as significant, height of supranuclear space (hSN) and number of mucous cells over 100 μm fold distance of intestinal mucosa (nM), which measures were significantly lower in fish from polluted area compared to the reference site. Obtained results indicated that combined histological and morphological approach on fish intestinal tissue might be used as a valuable biological tool for assessing pollution impact on

An EST-based approach for identifying genes expressed in the intestine and gills of pre-smolt Atlantic salmon (Salmo salar

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Adzhubei Alexei

2005-12-01

Full Text Available Abstract Background The Atlantic salmon is an important aquaculture species and a very interesting species biologically, since it spawns in fresh water and develops through several stages before becoming a smolt, the stage at which it migrates to the sea to feed. The dramatic change of habitat requires physiological, morphological and behavioural changes to prepare the salmon for its new environment. These changes are called the parr-smolt transformation or smoltification, and pre-adapt the salmon for survival and growth in the marine environment. The development of hypo-osmotic regulatory ability plays an important part in facilitating the transition from rivers to the sea. The physiological mechanisms behind the developmental changes are largely unknown. An understanding of the transformation process will be vital to the future of the aquaculture industry. A knowledge of which genes are expressed prior to the smoltification process is an important basis for further studies. Results In all, 2974 unique sequences, consisting of 779 contigs and 2195 singlets, were generated for Atlantic salmon from two cDNA libraries constructed from the gills and the intestine, accession numbers [Genbank: CK877169-CK879929, CK884015-CK886537 and CN181112-CN181464]. Nearly 50% of the sequences were assigned putative functions because they showed similarity to known genes, mostly from other species, in one or more of the databases used. The Swiss-Prot database returned significant hits for 1005 sequences. These could be assigned predicted gene products, and 967 were annotated using Gene Ontology (GO terms for molecular function, biological process and/or cellular component, employing an annotation transfer procedure. Conclusion This paper describes the construction of two cDNA libraries from pre-smolt Atlantic salmon (Salmo salar and the subsequent EST sequencing, clustering and assigning of putative function to 1005 genes expressed in the gills and/or intestine.

Effects of some chelating agents on the uptake and distribution of 54Mn(II) in the brown trout (Salmo trutta)

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Rouleau, C.; Tjaelve, H.; Pelletier, E.; Gottofrey, J.

1994-01-01

The effects of humic acids, which are natural metal-complexing compounds, and potassium ethylxanthate, sodium diethyldithiophosphate, sodium dimethyldithicarbamate, which are sulphur-containing man-made chelating agents, on the uptake and tissue distribution of 54 Mn(II) were studied in brown trout (Salmo trutta). Fish were exposed for 7 days to 0.1 μg Mn(II)x. -2 as NmCl 2 (l μCia 54 Mnxl -1 ) with or without chelat agents. Examination of the partition of Mn between octanol and a Tris-HCl buffer in the presence of these compounds was also performed. Humic acids had only small effects on Mn uptake and distribution in trout, probably because of the low stability of Mn-humate complexes. Partition of Mn in the presence of potassium ethylxanthate, sodium diethyldithiophosphate, sodium dimethyldithiocarbamate, and sodium diethyldithiocarbamate between octanol and Tris-HCl buffer showed formation of lipophilic complex with the latter two compounds, but not with the former. However, these four chelating agents all decreased Mn uptake in the trout by 40-45%. These substances also changed the distribution of Mn within the fish, with a higher proportion of the metal being present in some visceral organs and a smaller proportion being localized in some non-parenchymateous tissues, such as skin, fins and bones. The mechanisms underlying these effects are not known. however, the interaction of chelating agents with the Mn, although weak, may have partially withdrawn the metal from the uptake process inthe gills. The redistribution of Mn in the fish may be due to the binding of the metal to complexing compounds which have reached the intestinal lumen. Previous studies with other metals have shown increased or unchanged metal levels in tissues of fish at exposure together with potasium ethylxanthate, sodium diethyldithiophosphate, sodium dimethyldithiocarbamate, and sodium diethyldithiocarbamate, but decreased metal levels have not been observed before. (au) (37 refs.)

Contrast of degraded and restored stream habitat using an individual-based salmon model

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S. F. Railsback; M. Gard; Bret Harvey; Jason White; J.K.H. Zimmerman

2013-01-01

Stream habitat restoration projects are popular, but can be expensive and difficult to evaluate. We describe inSALMO, an individual-based model designed to predict habitat effects on freshwater life stages (spawning through juvenile out-migration) of salmon. We applied inSALMO to Clear Creek, California, simulating the production of total and large (>5 cm FL)...

Are brown trout Salmo trutta fario and rainbow trout Oncorhynchus mykiss two of a kind? A comparative study of salmonids to temperature-influenced Tetracapsuloides bryosalmonae infection.

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Bailey, C; Schmidt-Posthaus, H; Segner, H; Wahli, T; Strepparava, N

2018-02-01

Proliferative kidney disease (PKD) of salmonids caused by Tetracapsuloides bryosalmonae causes high mortalities of wild brown trout (Salmo trutta fario) and farmed rainbow trout (Oncorhynchus mykiss) at elevated water temperatures. Here the aim was to compare the temperature-dependent modulation of T. bryosalmonae in the two salmonid host species, which display different temperature optima. We used a novel experimental set-up in which we exposed brown trout and rainbow trout to an identical quantified low concentration of T. bryosalmonae for a short time period (1 hr). We followed the development of the parasite in the fish hosts for 70 days. PKD prevalence and parasite kinetics were assessed using qPCR. Exposures were performed at temperatures (12°C and 15°C) that reflect an environmental scenario that may occur in the natural habitat of salmonids. T. bryosalmonae infection was confirmed earliest in brown trout kept at 15°C (day 7 post-exposure) while, in all other groups, T. bryosalmonae was not confirmed until day 15 post-exposure. Moreover, significantly greater infection prevalence and a faster increase of parasite intensity were observed in brown trout kept at 15°C than in all other groups. These results indicate that PKD is differentially modulated by water temperature in related host species. © 2017 John Wiley & Sons Ltd.

Alginate Microencapsulation for Oral Immunisation of Finfish: Release Characteristics, Ex Vivo Intestinal Uptake and In Vivo Administration in Atlantic Salmon, Salmo salar L.

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Ghosh, Bikramjit; Nowak, Barbara F; Bridle, Andrew R

2015-12-01

This study examined the feasibility of alginate microcapsules manufactured using a low-impact technology and reagents to protect orally delivered immunogens for use as immunoprophylactics for fish. Physical characteristics and protein release kinetics of the microcapsules were examined at different pH and temperature levels using a microencapsulated model protein, bovine serum albumin (BSA). Impact of the microencapsulation process on contents was determined by analysing change in bioactivity of microencapsulated lysozyme. Feasibility of the method for oral immunoprophylaxis of finfish was assessed using FITC-labelled microcapsules. These were applied to distal intestinal explants of Atlantic salmon (Salmo salar) to investigate uptake ex vivo. Systemic distribution of microcapsules was investigated by oral administration of FITC-labelled microcapsules to Atlantic salmon fry by incorporating into feed. The microcapsules produced were structurally robust and retained surface integrity, with a modal size distribution of 250-750 nm and a tendency to aggregate. Entrapment efficiency of microencapsulation was 51.2 % for BSA and 43.2 % in the case of lysozyme. Microcapsules demonstrated controlled release of protein, which increased with increasing pH or temperature, and the process had no significant negative effect on bioactivity of lysozyme. Uptake of fluorescent-labelled microcapsules was clearly demonstrated by intestinal explants over a 24-h period. Evidence of microcapsules was found in the intestine, spleen, kidney and liver of fry following oral administration. Amenability of the microcapsules to intestinal uptake and distribution reinforced the strong potential for use of this microencapsulation method in oral immunoprophylaxis of finfish using sensitive immunogenic substances.

American River Watershed Investigation, California. Volume 6. Appendix S. Part 1

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1991-12-01

rainbow trout Salmo qairdneri hardhead Mylopharodon conocephalus Chinook salmon Oncorhynchus tshawvtscha brown trout Salmo trutta 0 34 Disturbance of...Department of Fish and Game Stream Survey 1938 Sacramento pike Pvtocheilus grandis hardhead Mylopharodon conocephalus roach Hesperoleucas symmetricus...Lazuli bunting Passerina amoena R,G,W,F Rufous-sided towhee Pipilo erythrophthalmus C,U,F Brown towhee Pipilo fuscus C,U,F Rufous-crowned sparrow

The mating brain: early maturing sneaker males maintain investment into the brain also under fast body growth in Atlantic salmon (Salmo salar).

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Kotrschal, Alexander; Trombley, Susanne; Rogell, Björn; Brannström, Ioana; Foconi, Eric; Schmitz, Monika; Kolm, Niclas

It has been suggested that mating behaviours require high levels of cognitive ability. However, since investment into mating and the brain both are costly features, their relationship is likely characterized by energetic trade-offs. Empirical data on the subject remains equivocal. We investigated if early sexual maturation was associated with brain development in Atlantic salmon ( Salmo salar ), in which males can either stay in the river and sexually mature at a small size (sneaker males) or migrate to the sea and delay sexual maturation until they have grown much larger (anadromous males). Specifically, we tested how sexual maturation may induce plastic changes in brain development by rearing juveniles on either natural or ad libitum feeding levels. After their first season we compared brain size and brain region volumes across both types of male mating tactics and females. Body growth increased greatly across both male mating tactics and females during ad libitum feeding as compared to natural feeding levels. However, despite similar relative increases in body size, early maturing sneaker males maintained larger relative brain size during ad libitum feeding levels as compared to anadromous males and females. We also detected several differences in the relative size of separate brain regions across feeding treatments, sexes and mating strategies. For instance, the relative size of the cognitive centre of the brain, the telencephalon, was largest in sneaker males. Our data support that a large relative brain size is maintained in individuals that start reproduction early also during fast body growth. We propose that the cognitive demands during complex mating behaviours maintain a high level of investment into brain development in reproducing individuals.

Collagen type XI alpha1 may be involved in the structural plasticity of the vertebral column in Atlantic salmon (Salmo salar L.).

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Wargelius, A; Fjelldal, P G; Nordgarden, U; Grini, A; Krossøy, C; Grotmol, S; Totland, G K; Hansen, T

2010-04-01

Atlantic salmon (Salmo salar L.) vertebral bone displays plasticity in structure, osteoid secretion and mineralization in response to photoperiod. Other properties of the vertebral bone, such as mineral content and mechanical strength, are also associated with common malformations in farmed Atlantic salmon. The biological mechanisms that underlie these changes in bone physiology are unknown, and in order to elucidate which factors might be involved in this process, microarray assays were performed on vertebral bone of Atlantic salmon reared under natural or continuous light. Eight genes were upregulated in response to continuous light treatment, whereas only one of them was upregulated in a duplicate experiment. The transcriptionally regulated gene was predicted to code for collagen type XI alpha1, a protein known to be involved in controlling the diameter of fibrillar collagens in mammals. Furthermore, the gene was highly expressed in the vertebrae, where spatial expression was found in trabecular and compact bone osteoblasts and in the chordoblasts of the notochordal sheath. When we measured the expression level of the gene in the tissue compartments of the vertebrae, the collagen turned out to be 150 and 25 times more highly expressed in the notochord and compact bone respectively, relative to the expression in the trabecular bone. Gene expression was induced in response to continuous light, and reduced in compressed vertebrae. The downregulation in compressed vertebrae was due to reduced expression in the compact bone, while expression in the trabecular bone and the notochord was unaffected. These data support the hypothesis that this gene codes for a presumptive collagen type XI alpha1, which may be involved in the regulatory pathway leading to structural adaptation of the vertebral architecture.

Measurement of total Zn and Zn isotope ratios by quadrupole ICP-MS for evaluation of Zn uptake in gills of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss)

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Wolf, R.E.; Todd, A.S.; Brinkman, S.; Lamothe, P.J.; Smith, K.S.; Ranville, J.F.

2009-01-01

This study evaluates the potential use of stable zinc isotopes in toxicity studies measuring zinc uptake by the gills of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss). The use of stable isotopes in such studies has several advantages over the use of radioisotopes, including cost, ease of handling, elimination of permit requirements, and waste disposal. A pilot study using brown trout was performed to evaluate sample preparation methods and the ability of a quadrupole inductively coupled plasma mass spectrometer (ICP-MS) system to successfully measure changes in the 67Zn/66Zn ratios for planned exposure levels and duration. After completion of the pilot study, a full-scale zinc exposure study using rainbow trout was performed. The results of these studies indicate that there are several factors that affect the precision of the measured 67Zn/66Zn ratios in the sample digests, including variations in sample size, endogenous zinc levels, and zinc uptake rates by individual fish. However, since these factors were incorporated in the calculation of the total zinc accumulated by the gills during the exposures, the data obtained were adequate for their intended use in calculating zinc binding and evaluating the influences of differences in water quality parameters.

Effect of nutritional status and sampling intensity on recovery after dorsal aorta cannulation in free-swimming Atlantic salmon (Salmo salar L.).

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Djordjevic, B; Kristensen, T; Øverli, Ø; Rosseland, B O; Kiessling, A

2012-02-01

Recovery from implantation of a cannula in the dorsal aorta (DA) of Atlantic salmon (Salmo salar) was studied in relation to nutritional status and sampling intensity. The incentive for the study was the inconsistency between published reports and our own experience of recovery and longevity of fish exposed to this protocol. In two studies using starved fish, blood (0.3 ml) was sampled 0, 1 and 24 h after DA-cannulation, and thereafter at 48 and 72 h and thereafter once weekly for four weeks. In a third study using fed fish, four consecutive samples (0, 3, 6 and 12 h after a meal) were obtained twice a week over a four-week period. All fish displayed a sharp increase in pCO(2) and haematocrit (Hct) during surgery, followed by a marked raise in cortisol, glucose, sodium and potassium (1 h). pCO(2), pH and Hct approached baseline levels as early as the 1 h post-surgery sample, while this was not the case for cortisol and electrolytes before the 24 h post-surgery sample. Glucose did not display any significant changes post surgery. From then on, all variables displayed minor but non-significant (P > 0.05) changes indicating a steady state close to baseline values for unstressed fish. This pattern was independent of sampling procedure, i.e. repeated single or multiple samples and thus volume of blood removed. Nutritional status (fed vs. starved) did not affect post-surgical recovery pattern. Only K(+) and Hct displayed consistent and significant post-prandial patterns. We found marked differences between baseline level of cannulated fish and uncannulated control fish, in pH, K(+) and Hct indicating that cannulation may be the preferred method to obtain representative resting values in fish.

Identification of differentially expressed genes of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss) in response to Tetracapsuloides bryosalmonae (Myxozoa).

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Kumar, Gokhlesh; Abd-Elfattah, Ahmed; El-Matbouli, Mansour

2015-03-01

Tetracapsuloides bryosalmonae Canning et al., 1999 (Myxozoa) is the causative agent of proliferative kidney disease in various species of salmonids in Europe and North America. We have shown previously that the development and distribution of the European strain of T. bryosalmonae differs in the kidney of brown trout (Salmo trutta) Linnaeus, 1758 and rainbow trout (Oncorhynchus mykiss) Walbaum, 1792, and that intra-luminal sporogonic stages were found in brown trout but not in rainbow trout. We have now compared transcriptomes from kidneys of brown trout and rainbow trout infected with T. bryosalmonae using suppressive subtractive hybridization (SSH). The differentially expressed transcripts produced by SSH were cloned, transformed, and tested by colony PCR. Differential expression screening of PCR products was validated using dot blot, and positive clones having different signal intensities were sequenced. Differential screening and a subsequent NCBI-BLAST analysis of expressed sequence tags revealed nine clones expressed differently between both fish species. These differentially expressed genes were validated by quantitative real-time PCR of kidney samples from both fish species at different time points of infection. Expression of anti-inflammatory (TSC22 domain family protein 3) and cell proliferation (Prothymin alpha) genes were upregulated significantly in brown trout but downregulated in rainbow trout. The expression of humoral immune response (immunoglobulin mu) and endocytic pathway (Ras-related protein Rab-11b) genes were significantly upregulated in rainbow trout but downregulated in brown trout. This study suggests that differential expression of host anti-inflammatory, humoral immune and endocytic pathway responses, cell proliferation, and cell growth processes do not inhibit the development of intra-luminal sporogonic stages of the European strain of T. bryosalmonae in brown trout but may suppress it in rainbow trout.

Nutritional Evaluation of an EPA-DHA Oil from Transgenic Camelina sativa in Feeds for Post-Smolt Atlantic Salmon (Salmo salar L..

Directory of Open Access Journals (Sweden)

Mónica B Betancor

Full Text Available Vegetable oils (VO are possible substitutes for fish oil in aquafeeds but their use is limited by their lack of omega-3 (n-3 long-chain polyunsaturated fatty acids (LC-PUFA. However, oilseed crops can be modified to produce n-3 LC-PUFA such as eicosapentaenoic (EPA and docosahexaenoic (DHA acids, representing a potential option to fill the gap between supply and demand of these important nutrients. Camelina sativa was metabolically engineered to produce a seed oil with around 15% total n-3 LC-PUFA to potentially substitute for fish oil in salmon feeds. Post-smolt Atlantic salmon (Salmo salar were fed for 11-weeks with one of three experimental diets containing either fish oil (FO, wild-type Camelina oil (WCO or transgenic Camelina oil (DCO as added lipid source to evaluate fish performance, nutrient digestibility, tissue n-3 LC-PUFA, and metabolic impact determined by liver transcriptome analysis. The DCO diet did not affect any of the performance or health parameters studied and enhanced apparent digestibility of EPA and DHA compared to the WCO diet. The level of total n-3 LC-PUFA was higher in all the tissues of DCO-fed fish than in WCO-fed fish with levels in liver similar to those in fish fed FO. Endogenous LC-PUFA biosynthetic activity was observed in fish fed both the Camelina oil diets as indicated by the liver transcriptome and levels of intermediate metabolites such as docosapentaenoic acid, with data suggesting that the dietary combination of EPA and DHA inhibited desaturation and elongation activities. Expression of genes involved in phospholipid and triacylglycerol metabolism followed a similar pattern in fish fed DCO and WCO despite the difference in n-3 LC-PUFA contents.

Nutritional Evaluation of an EPA-DHA Oil from Transgenic Camelina sativa in Feeds for Post-Smolt Atlantic Salmon (Salmo salar L.).

Science.gov (United States)

Betancor, Mónica B; Sprague, Matthew; Sayanova, Olga; Usher, Sarah; Metochis, Christoforos; Campbell, Patrick J; Napier, Johnathan A; Tocher, Douglas R

2016-01-01

Vegetable oils (VO) are possible substitutes for fish oil in aquafeeds but their use is limited by their lack of omega-3 (n-3) long-chain polyunsaturated fatty acids (LC-PUFA). However, oilseed crops can be modified to produce n-3 LC-PUFA such as eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids, representing a potential option to fill the gap between supply and demand of these important nutrients. Camelina sativa was metabolically engineered to produce a seed oil with around 15% total n-3 LC-PUFA to potentially substitute for fish oil in salmon feeds. Post-smolt Atlantic salmon (Salmo salar) were fed for 11-weeks with one of three experimental diets containing either fish oil (FO), wild-type Camelina oil (WCO) or transgenic Camelina oil (DCO) as added lipid source to evaluate fish performance, nutrient digestibility, tissue n-3 LC-PUFA, and metabolic impact determined by liver transcriptome analysis. The DCO diet did not affect any of the performance or health parameters studied and enhanced apparent digestibility of EPA and DHA compared to the WCO diet. The level of total n-3 LC-PUFA was higher in all the tissues of DCO-fed fish than in WCO-fed fish with levels in liver similar to those in fish fed FO. Endogenous LC-PUFA biosynthetic activity was observed in fish fed both the Camelina oil diets as indicated by the liver transcriptome and levels of intermediate metabolites such as docosapentaenoic acid, with data suggesting that the dietary combination of EPA and DHA inhibited desaturation and elongation activities. Expression of genes involved in phospholipid and triacylglycerol metabolism followed a similar pattern in fish fed DCO and WCO despite the difference in n-3 LC-PUFA contents.

River Liffey survey. II. The food consumed by the brown trout (Salmo trutta. L. ) in acid and alkaline waters

Energy Technology Data Exchange (ETDEWEB)

Frost, W E

1939-01-01

The brown trout (Salmo trutta) of the fresh waters of Ireland may be divided roughly into two categories, small slow-growing fish found in acid waters derived from non-lime-bearing rocks and larger quick-growing fish found in alkaline waters derived from lime-bearing rocks. The food of the trout from two contrasting stations, one where the water is acid and the other where it is alkaline, has been investigated. The stations are on the R. Liffey; the acid water one, Ballysmuttan (pH 4.4 to 6.8, usually 5.6), and the alkaline station (pH 7.4 to 8.4, usually 7.8 to 8.0) at Straffan. The trout were caught by rod and line, 349 specimens from Ballysmuttan, 228 from Straffan. The food eaten at Ballysmuttan during the months of January to December and at Straffan during February to October is compared and contrasted. The stomach contents of the trout have been weighed and the ratio of the weight of food to the total body weight has been determined. The food organisms have been classified as surface, mid-water, and bottom food. On the whole a higher percentage of surface organisms and of surface feeding fish is found at Straffan than at Ballysmuttan, but at both stations the proportion of bottom food organisms and fish feeding on them is higher than that for surface organisms and feeders. The size of the trout in relation to the kind of food eaten is described for both stations. An account of the food eaten during the winter months (November, December, and January) by the Ballysmuttan trout is given. The question of food and its effect on the size and growth of trout from acid and alkaline waters is discussed in the light of the data obtained from Ballysmuttan and Straffan. The evidence from these two places suggests that probably some factor other than that of the amount of food conditions affects the difference of size and growth rate of the trout from the two stations.

An analysis of genetic stock identification on a small geographical scale using microsatellite markers, and its application in the management of a mixed-stock fishery for Atlantic salmon Salmo salar in Ireland.

Science.gov (United States)

Ensing, D; Crozier, W W; Boylan, P; O'Maoiléidigh, N; McGinnity, P

2013-06-01

A genetic stock identification (GSI) study was undertaken in a fishery for Atlantic salmon Salmo salar to determine the effects of restrictive fishery management measures on the stock composition of the fishery, and if accurate and precise stock composition estimates could be achieved on the small geographical scale where this fishery operates, using a suite of only seven microsatellite loci. The stock composition of the Foyle fishery was shown to comprise almost exclusively of Foyle origin fish in the 3 years after restrictive measures were introduced in 2007, compared to 85% the year before. This showed that the restrictive measures resulted in the Foyle fishery being transformed from a mixed-stock fishery to an almost exclusively single-stock fishery, and showed how GSI studies can guide and evaluate management decisions to successfully manage these fisheries. Highly accurate and precise stock composition estimates were achieved in this study, using both cBAYES and ONCOR genetic software packages. This suggests accurate and precise stock composition is possible even on small geographical scales. © 2013 AFBINI. Journal of Fish Biology © 2013 The Fisheries Society of the British Isles.

Low levels of very-long-chain n-3 PUFA in Atlantic salmon (Salmo salar) diet reduce fish robustness under challenging conditions in sea cages.

Science.gov (United States)

Bou, Marta; Berge, Gerd M; Baeverfjord, Grete; Sigholt, Trygve; Østbye, Tone-Kari; Ruyter, Bente

2017-01-01

The present study aimed to determine the minimum requirements of the essential n -3 fatty acids EPA and DHA in Atlantic salmon ( Salmo salar ) that can secure their health under challenging conditions in sea cages. Individually tagged Atlantic salmon were fed 2, 10 and 17 g/kg of EPA + DHA from 400 g until slaughter size (about 3·5 kg). The experimental fish reared in sea cages were subjected to the challenging conditions typically experienced under commercial production. Salmon receiving the lowest EPA + DHA levels showed lower growth rates in the earlier life stages, but no significant difference in final weights at slaughter. The fatty acid composition of various tissues and organs had remarkably changed. The decreased EPA + DHA in the different tissue membrane phospholipids were typically replaced by pro-inflammatory n -6 fatty acids, most markedly in the skin. The EPA + DHA levels were maintained at a higher level in the liver and erythrocytes than in the muscle, intestine and skin. After delousing at high water temperatures, the mortality rates were 63, 52 and 16 % in the salmon fed 2, 10 and 17 g/kg EPA + DHA. Low EPA + DHA levels also increased the liver, intestinal and visceral fat amount, reduced intervertebral space and caused mid-intestinal hyper-vacuolisation. Thus, 10 g/kg EPA + DHA in the Atlantic salmon diet, a level previously regarded as sufficient, was found to be too low to maintain fish health under demanding environmental conditions in sea cages.

Dietary soya saponins increase gut permeability and play a key role in the onset of soyabean-induced enteritis in Atlantic salmon ( Salmo salar L.).

Science.gov (United States)

Knudsen, David; Jutfelt, Fredrik; Sundh, Henrik; Sundell, Kristina; Koppe, Wolfgang; Frøkiaer, Hanne

2008-07-01

Saponins are naturally occurring amphiphilic molecules and have been associated with many biological activities. The aim of the present study was to investigate whether soya saponins trigger the onset of soyabean-induced enteritis in Atlantic salmon (Salmo salar L.), and to examine if dietary soya saponins increase the epithelial permeability of the distal intestine in Atlantic salmon. Seven experimental diets containing different levels of soya saponins were fed to seawater-adapted Atlantic salmon for 53 d. The diets included a fishmeal-based control diet, two fishmeal-based diets with different levels of added soya saponins, one diet containing 25% lupin kernel meal, two diets based on 25% lupin kernel meal with different levels of added soya saponins, and one diet containing 25% defatted soyabean meal. The effect on intestinal morphology, intestinal epithelial permeability and faecal DM content was examined. Fish fed 25% defatted soyabean meal displayed severe enteritis, whereas fish fed 25% lupin kernel meal had normal intestinal morphology. The combination of soya saponins and fishmeal did not induce morphological changes but fish fed soya saponins in combination with lupin kernel meal displayed significant enteritis. Increased epithelial permeability was observed in fish fed 25% defatted soyabean meal and in fish fed soya saponin concentrate independent of the protein source in the feed. The study demonstrates that soya saponins, in combination with one or several unidentified components present in legumes, induce an inflammatory reaction in the distal intestine of Atlantic salmon. Soya saponins increase the intestinal epithelial permeability but do not, per se, induce enteritis.

Field trials in Norway with SLICE (0.2% emamectin benzoate) for the oral treatment of sea lice infestation in farmed Atlantic salmon Salmo salar.

Science.gov (United States)

Ramstad, A; Colquhoun, D J; Nordmo, R; Sutherland, I H; Simmons, R

2002-06-21

Four commercial salmon farms on the West coast of Norway were recruited to a programme of field trials in which the efficacy of SLICE (0.2% emamectin benzoate; Schering-Plough Animal Health) was compared with a commercially available product, EKTOBANN (teflubenzuron 2 g kg(-1); Skretting A/S) in treating natural sea lice Lepeophtheirus salmonis infections in Atlantic salmon Salmo salmar L. At each test site, 3 fish pens were treated with each product. In total, nearly 1.2 million first-year-class fish were included in the trial, of which approximately 561,000 received emamectin benzoate at a dosage of 50 microg kg(-1) body wt d(-1), while approximately 610,000 received teflubenzuron at a dosage of 10 mg kg(-1) body wt d(-1). Medicated feed was provided at 0.5% body wt d(-1) over 7 consecutive days. Feed containing emamectin benzoate was generally well accepted by the fish and no problems were encountered in feeding the medicated diet at the desired dose. Lice numbers were counted 2 d before and 1, 7, 14 and 21 d after commencement of treatment. While treatment with both substances rapidly reduced lice numbers, pens treated with emamectin benzoate were found to harbour significantly fewer lice 14 and 21 d post-treatment. Twenty-one days following treatment with emamectin benzoate the lice abundance was reduced on average by 94%. Limited sampling outside the main study period indicated that emamectin benzoate protects against sea-lice infestation over longer periods.

Structural alterations in embryos and alevins of the Atlantic salmon, Salmo salar 1. , induced by continuous or short-term exposure to acidic levels of pH

Energy Technology Data Exchange (ETDEWEB)

Daye, P.G.; Garside, E.T.

1980-01-01

Embryos of the Atlantic Salmon, salmo salar l., were incubated continuously from fertilization, at pH 6.8 (control), 5.0, 4.5, 4.3, 4.0, and 3.7, at 5-6 degrees C. The subsequent alvins in these environments were maintained at these levels for 40 days after hatching. Generally, lethal and sublethal injuries were separable only as to degree and distribution. Sublethal alterations occurred in the integument, gill blood, and blood vascular structures of all live alevins incubated at pH 5.0 and lower. At pH 4.5 and lower, injuries also occurred in brain, optic retina, kidney, and spleen. Some tissue regeneration occurred in the embryonal rudimentary integument at pH 4.5 and lower. Regeneration also occurred but to a lesser degree in pseudobranch, kidney, spleen, and erythrocytes. Injury of the integument was the apparent cause of death in prehatching embryos since it is the major site of respiration and ion exchange. As gills expand in posthatching alevins, they assume these functions and destruction of branchial epithelium then becomes the prime cause of death. The nature of cell injury and consequent dysgenesis at tissue and organ levels are not ascribable uniquely to acidic stress. Some injuries are similar to those caused variously by heavy metals, detergents, halogenated organic compounds, some petroleum fractions, and chronic and acute high temperature in postalevin stages of several species of fish.

Precision-Cut Liver Slices of Salmo salar as a tool to investigate the oxidative impact of CYP1A-mediated PCB 126 and 3-methylcholanthrene metabolism.

Science.gov (United States)

Lemaire, Benjamin; Beck, Michaël; Jaspart, Mélanie; Debier, Cathy; Calderon, Pedro Buc; Thomé, Jean-Pierre; Rees, Jean-François

2011-02-01

Fish isolated cell systems have long been used to predict in vivo toxicity of man-made chemicals. In present study, we tested the suitability of Precision-Cut Liver Slices (PCLS) as an alternative to these models that allows the evaluation of a global tissue response to toxicants, to investigate oxidative stress response to cytochrome P450 1A (CYP1A) induction in fish liver. PCLS of Salmo salar were exposed for 21 h to increasing doses of 3-methylcholanthrene (3-MC) and Polychlorobiphenyl 126 (PCB 126). 3-MC (25 μM) strongly induced CYP1A transcription. In dose-response analysis (25-100 μM), EROD activity was strongly increased at intermediate 3-MC concentrations. We found the counter-intuitive decline of EROD at the highest 3-MC doses to result from reversible competition with ethoxyresorufin. No increases of H(2)O(2) production, antioxidant enzymes activities or oxidative damage to lipids were found with 3-MC treatments. PCLS subjected to PCB 126 (2-200 nM) showed increased contamination levels and a parallel increased CYP1A mRNA synthesis and EROD activity. H(2)O(2) production tended to increase but no oxidative damage to lipids was found. As antioxidant enzymes activities declined at the highest PCB 126 dose, it is suggested that longer incubation periods could be required to generate oxidative stress in PCLS. Copyright © 2010 Elsevier Ltd. All rights reserved.

Chronic dietary mercury exposure causes oxidative stress, brain lesions, and altered behaviour in Atlantic salmon (Salmo salar) parr

International Nuclear Information System (INIS)

Berntssen, Marc H.G.; Aatland, Aase; Handy, Richard D.

2003-01-01

Atlantic salmon (Salmo salar L.) parr were fed for 4 months on fish meal based diets supplemented with mercuric chloride (0, 10, or 100 mg Hg kg -1 DW) or methylmercury chloride (0, 5, or 10 mg Hg kg -1 DW) to assess the effects of inorganic (Hg) and organic dietary mercury on brain lipid peroxidation and neurotoxicity. Lipid peroxidative products, endogenous anti oxidant enzymes, brain histopathology, and overall behaviour were measured. Methylmercury accumulated significantly in the brain of fish fed 5 or 10 mg kg -1 by the end of the experiment, and inorganic mercury accumulated significantly in the brain only at 100 mg kg -1 exposure levels. No mortality or growth reduction was observed in any of the exposure groups. Fish fed 5 mg kg -1 methylmercury had a significant increase (2-fold) in the antioxidant enzyme super oxide dismutase (SOD) in the brain. At dietary levels of 10 mg kg -1 methylmercury, a significant increase (7-fold) was observed in lipid peroxidative products (thiobarbituric acid reactive substances, TBARS) and a subsequently decrease (1.5-fold) in anti oxidant enzyme activity (SOD and glutathione peroxidase, GSH-Px). Fish fed 10 mg kg -1 methylmercury also had pathological damage (vacoulation and necrosis), significantly reduced neural enzyme activity (5-fold reduced monoamine oxidase, MAO, activity), and reduced overall post-feeding activity behaviour. Pathological injury started in the brain stem and became more widespread in other areas of the brain at higher exposure levels. Fish fed 100 mg Hg kg -1 inorganic mercury had significant reduced neural MAO activity and pathological changes (astrocyte proliferation) in the brain, however, neural SOD and GSH-Px enzyme activity, lipid peroxidative products (TBARS), and post feeding behaviour did not differ from controls. Compared with other organs, the brain is particular susceptible for dietary methylmercury induced lipid peroxidative stress at relative low exposure concentrations. Doses of dietary

(Teleostei: Characiformes) an

Indian Academy of Sciences (India)

2Departamento de Morfologia, Instituto de Biociências, Universidade Estadual Paulista, ... Keywords. molecular markers; fish conservation; aquaculture; polymorphic DNA. .... species complex in the upper rio Tibagi Basin (Paraná, Brazil).

Strong Effects of Temperature on the Early Life Stages of a Cold Stenothermal Fish Species, Brown Trout (Salmo trutta L.).

Science.gov (United States)

Réalis-Doyelle, Emilie; Pasquet, Alain; De Charleroy, Daniel; Fontaine, Pascal; Teletchea, Fabrice

2016-01-01

Temperature is the main abiotic factor that influences the life cycle of poikilotherms. The present study investigated the thermal tolerance and phenotypic plasticity of several parameters (development time, morphometric measures, bioenergetics) for both embryos and fry of a cold stenothermal fish species, brown trout (Salmo trutta L.) in order to allow for a holistic evaluation of the potential effects of temperature. Five temperatures (4°C, 6°C, 8°C, 10°C, and 12°C) were tested, and the effects of temperature were analyzed at three stages: hatching, emergence, and first food intake. A mean of 5,440 (S.E. ± 573) eggs, coming from seven females and seven males (seven families) captured close to Linkebeek (Belgium), were used for each temperature. Maximum survival of well-formed fry at first food intake and better use of energy budget were found at 6°C and 8°C, temperatures at which the possible contribution to the next generation should therefore be greatest. At 12°C, the experimental population fell dramatically (0.9% survival rate for well-formed fry at first food intake), and fry had almost no yolk sac at first food intake. The present results on survival at 12°C are in accordance with predictions of a sharp decrease in brown trout numbers in France over the coming decades according to climate change projections (1°C to 5°C temperature rise by 2100 for France). At 10°C, there was also a lower survival rate (55.4% at first food intake). At 4°C, the survival rate was high (76.4% at first food intake), but the deformity rate was much higher (22% at first food intake) than at 6°C, 8°C, and 10°C. The energetic budget showed that at the two extreme temperatures (4°C and 12°C) there was less energy left in the yolk sac at first food intake, suggesting a limited ability to survive starvation.

Oil from transgenic Camelina sativa containing over 25 % n-3 long-chain PUFA as the major lipid source in feed for Atlantic salmon (Salmo salar).

Science.gov (United States)

Betancor, Mónica B; Li, Keshuai; Bucerzan, Valentin S; Sprague, Matthew; Sayanova, Olga; Usher, Sarah; Han, Lihua; Norambuena, Fernando; Torrissen, Ole; Napier, Johnathan A; Tocher, Douglas R; Olsen, Rolf E

2018-06-01

Facing a bottleneck in the growth of aquaculture, and a gap in the supply and demand of the highly beneficial n-3 long-chain PUFA (LC-PUFA), sustainable alternatives to traditional marine-based feeds are required. Therefore, in the present trial, a novel oil obtained from a genetically engineered oilseed crop, Camelina sativa, that supplied over 25 % n-3 LC-PUFA was tested as a sole dietary-added lipid source in Atlantic salmon (Salmo salar) feed. Three groups of fish were fed three experimental diets for 12 weeks with the same basal composition and containing 20 % added oil supplied by either a blend of fish oil and rapeseed oil (1:3) (COM) reflecting current commercial formulations, wild-type Camelina oil (WCO) or the novel transgenic Camelina oil (TCO). There were no negative effects on the growth, survival rate or health of the fish. The whole fish and flesh n-3 LC-PUFA levels were highest in fish fed TCO, with levels more than 2-fold higher compared with those of fish fed the COM and WCO diets, respectively. Diet TCO had no negative impacts on the evaluated immune and physiological parameters of head kidney monocytes. The transcriptomic responses of liver and mid-intestine showed only mild effects on metabolism genes. Overall, the results clearly indicated that the oil from transgenic Camelina was highly efficient in supplying n-3 LC-PUFA providing levels double that obtained with a current commercial standard, and similar to those a decade ago before substantial dietary fishmeal and oil replacement.

Tetracapsuloides bryosalmonae infection affects the expression of genes involved in cellular signal transduction and iron metabolism in the kidney of the brown trout Salmo trutta.

Science.gov (United States)

Kumar, Gokhlesh; Sarker, Subhodeep; Menanteau-Ledouble, Simon; El-Matbouli, Mansour

2015-06-01

Tetracapsuloides bryosalmonae is an enigmatic endoparasite which causes proliferative kidney disease in various species of salmonids in Europe and North America. The life cycle of the European strain of T. bryosalmonae generally completes in an invertebrate host freshwater bryozoan and vertebrate host brown trout (Salmo trutta) Linnaeus, 1758. Little is known about the gene expression in the kidney of brown trout during the developmental stages of T. bryosalmonae. In the present study, quantitative real-time PCR was applied to quantify the target genes of interest in the kidney of brown trout at different time points of T. bryosalmonae development. PCR primers specific for target genes were designed and optimized, and their gene expression levels were quantified in the cDNA kidney samples using SYBR Green Supermix. Expression of Rab GDP dissociation inhibitor beta, integral membrane protein 2B, NADH dehydrogenase 1 beta subcomplex subunit 6, and 26S protease regulatory subunit S10B were upregulated significantly in infected brown trout, while the expression of the ferritin M middle subunit was downregulated significantly. These results suggest that host genes involved in cellular signal transduction, proteasomal activities, including membrane transporters and cellular iron storage, are differentially upregulated or downregulated in the kidney of brown trout during parasite development. The gene expression pattern of infected renal tissue may support the development of intraluminal sporogonic stages of T. bryosalmonae in the renal tubular lumen of brown trout which may facilitate the release of viable parasite spores to transmit to the invertebrate host bryozoan.

Species complexes and phylogenetic lineages of Hoferellus (Myxozoa, Cnidaria) including revision of the genus: A problematic case for taxonomy

Czech Academy of Sciences Publication Activity Database

Alama-Bermejo, Gema; Jirků, Miloslav; Kodádková, Alena; Pecková, Hana; Fiala, Ivan; Holzer, Astrid S.

2016-01-01

Roč. 9, JAN 11 (2016), č. článku 13. ISSN 1756-3305 R&D Projects: GA ČR GBP505/12/G112; GA ČR GAP506/10/2330; GA ČR(CZ) GP14-28784P Grant - others:AV ČR(CZ) M200961205 Institutional support: RVO:60077344 Keywords : Amphibia * Anura * fish * Carassius * Cyprinus carpio * ITS cloning * mode of attachment * Teleostei * ultrastructure Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 3.080, year: 2016

REPRODUCTION DE LA TRUITE (Salmo trutta L. DANS LETORRENT DE CHEVENNE, HAUTE-SAVOIE.UN FONCTIONNEMENT ORIGINAL ?

Directory of Open Access Journals (Sweden)

CHAMPIGNEULLE A.

2003-01-01

Full Text Available La reproduction d’une population de truite (Salmo trutta L. de forme essentiellement méditerranéenne est décrite dans le ruisseau du Chevenne, un torrent à forte pente (10 % entrecoupé d’obstacles et limité en substrat de frai, situé dans les Alpes savoyardes. Les reproducteurs (résidents du torrent ou migrants issus du cours principal diffèrent en taille et sexe-ratio. La majorité (58 % des femelles migrantes entrent dans l’affluent déjà ovulées. Il existe une fort gradient décroissant aval-amont dans la répartition des géniteurs et des frayères. Les 157 frayères décrites montrent une grande diversité de microhabitats (5 types principaux utilisés pour la reproduction, avec un pourcentage élevé (65 % de frayères construites dans des sites protégés ayant une faible vitesse de courant (< 20 cm/s. La reproduction débute en radier, l’habitat de frai classique, puis elle s’étend ensuite aux autres microhabitats avant que le frai en milieu radier ne soit achevé. Une évaluation de la disponibilité et de l’utilisation du substrat favorable au frai (taille de 1 à 3 cm dans les divers microhabitats a été réalisée a posteriori. Le microhabitat « côté de pool » (inhabituel pour le frai est autant utilisé que le milieu radier. Les lentilles de substrat favorable, abritées en bordure de berge ou dans les courants sont préférées alors que les lentilles de substrat non protégées dans les courants sont évitées. Une crue en fin de la période de frai a totalement détruit 36 % des frayères avec un taux de destruction totale très variable selon le type de microhabitat de frai. Les frayères creusées en côté de pool et en bordure de berge protégées du courant ont été moins détruites (15-17 % de destruction totale que dans les autres microhabitats (50 à 67 % de destruction totale. La diversité des sites de frai pourrait donc être une composante essentielle à la survie de la population de

Uptake and effects of uranium nanoparticles on early life stage of Atlantic salmon (Salmo salar)

Energy Technology Data Exchange (ETDEWEB)

Kleiven, M.; Teien, H.C.; Lind, O.C.; Vaa Johnsen, I.; Oughton, D.; Salbu, B. [Norwegian University of Life Sciences (Norway)

2014-07-01

Nanotechnology has been, and still is, a major scientific and economic growth area. Over the last decade, the awareness of nano-material as a potential human and environmental hazard has increased dramatically. Being a naturally occurring radionuclide, as well as the major fuel material used in nuclear energy power plants, many sources of uranium (U) are found in the environment. Uranium nanoparticles (NPs) can occur naturally (i.e., colloidal species), as incidental anthropogenic sources (e.g., debris from depleted U weapons and fuel manufacture and reprocessing), or can be intentionally synthesized for use as catalysts. Studies on environmental aspects of U NPs are rather scarce in literature. Thus, the focus of the present work was to obtain information on uptake and potential effects of U NPs on early life stage of Atlantic salmon (Salmo salar). Eggs of Atlantic salmon were exposed to two types of U NPs, U{sub 3}O{sub 8} and UO{sub 2}, as well as to uranyl ions, in natural soft water (TOC 4.5 mg/L) at pH 7.2. Two U NP exposure experiments during fertilization were performed, both with exposure for 24 h. The exposure period was followed by a depuration period in uncontaminated water (7 and 69 days of depuration, respectively). Exposure solutions were subject to a suite of techniques to characterize the exposure during the experiment. Dissection of eggs was performed prior to the determination of U to distinguish between U associated to the shell and U in the egg fluid. Results showed that U was highest in eggs exposed to uranyl, especially during the stage of swelling, and the uptake into the eggs increased with exposure time. The uptake of U in eggs exposed to U NPs was only minor, and may be due to U ions in exposure solutions or released from U-NPs, rather than an actual U NP uptake. However, on the surface of eggs exposed to U NPs large amounts of U NPs were deposited during the experimental duration period, potentially posing a risk over time. There were no

Hepatic transcriptional responses in Atlantic salmon (Salmo salar) exposed to gamma radiation and depleted uranium singly and in combination

Energy Technology Data Exchange (ETDEWEB)

Song, You, E-mail: yso@niva.no [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, N-0349 Oslo (Norway); Salbu, Brit; Teien, Hans-Christian [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Evensen, Øystein [Norwegian University of Life Sciences (NMBU), Department of Basic Sciences and Aquatic Medicine, P.O. Box 8146 Dep., N-0033 Oslo (Norway); Lind, Ole Christian [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Rosseland, Bjørn Olav [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Norwegian University of Life Sciences (NMBU), Department of Ecology and Natural Resource Management (INA), P.O. Box 5003, N-1432 Ås (Norway); and others

2016-08-15

Radionuclides are a special group of substances posing both radiological and chemical hazards to organisms. As a preliminary approach to understand the combined effects of radionuclides, exposure studies were designed using gamma radiation (Gamma) and depleted uranium (DU) as stressors, representing a combination of radiological (radiation) and chemical (metal) exposure. Juvenile Atlantic salmon (Salmo salar) were exposed to 70 mGy external Gamma dose delivered over the first 5 h of a 48 h period (14 mGy/h), 0.25 mg/L DU were exposed continuously for 48 h and the combination of the two stressors (Combi). Water and tissue concentrations of U were determined to assess the exposure quality and DU bioaccumulation. Hepatic gene expression changes were determined using microarrays in combination with quantitative real-time reverse transcription polymerase chain reaction (qPCR). Effects at the higher physiological levels were determined as plasma glucose (general stress) and hepatic histological changes. The results show that bioaccumulation of DU was observed after both single DU and the combined exposure. Global transcriptional analysis showed that 3122, 2303 and 3460 differentially expressed genes (DEGs) were significantly regulated by exposure to gamma, DU and Combi, respectively. Among these, 349 genes were commonly regulated by all treatments, while the majority was found to be treatment-specific. Functional analysis of DEGs revealed that the stressors displayed similar mode of action (MoA) across treatments such as induction of oxidative stress, DNA damage and disturbance of oxidative phosphorylation, but also stressor-specific mechanisms such as cellular stress and injury, metabolic disorder, programmed cell death, immune response. No changes in plasma glucose level as an indicator of general stress and hepatic histological changes were observed. Although no direct linkage was successfully established between molecular responses and adverse effects at the organism

Hepatic transcriptional responses in Atlantic salmon (Salmo salar) exposed to gamma radiation and depleted uranium singly and in combination

International Nuclear Information System (INIS)

Song, You; Salbu, Brit; Teien, Hans-Christian; Evensen, Øystein; Lind, Ole Christian; Rosseland, Bjørn Olav

2016-01-01

Radionuclides are a special group of substances posing both radiological and chemical hazards to organisms. As a preliminary approach to understand the combined effects of radionuclides, exposure studies were designed using gamma radiation (Gamma) and depleted uranium (DU) as stressors, representing a combination of radiological (radiation) and chemical (metal) exposure. Juvenile Atlantic salmon (Salmo salar) were exposed to 70 mGy external Gamma dose delivered over the first 5 h of a 48 h period (14 mGy/h), 0.25 mg/L DU were exposed continuously for 48 h and the combination of the two stressors (Combi). Water and tissue concentrations of U were determined to assess the exposure quality and DU bioaccumulation. Hepatic gene expression changes were determined using microarrays in combination with quantitative real-time reverse transcription polymerase chain reaction (qPCR). Effects at the higher physiological levels were determined as plasma glucose (general stress) and hepatic histological changes. The results show that bioaccumulation of DU was observed after both single DU and the combined exposure. Global transcriptional analysis showed that 3122, 2303 and 3460 differentially expressed genes (DEGs) were significantly regulated by exposure to gamma, DU and Combi, respectively. Among these, 349 genes were commonly regulated by all treatments, while the majority was found to be treatment-specific. Functional analysis of DEGs revealed that the stressors displayed similar mode of action (MoA) across treatments such as induction of oxidative stress, DNA damage and disturbance of oxidative phosphorylation, but also stressor-specific mechanisms such as cellular stress and injury, metabolic disorder, programmed cell death, immune response. No changes in plasma glucose level as an indicator of general stress and hepatic histological changes were observed. Although no direct linkage was successfully established between molecular responses and adverse effects at the organism

Transcriptomic and physiological responses to fishmeal substitution with plant proteins in formulated feed in farmed Atlantic salmon (Salmo salar

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Tacchi Luca

2012-08-01

Full Text Available Abstract Background Aquaculture of piscivorous fish is in continual expansion resulting in a global requirement to reduce the dependence on wild caught fish for generation of fishmeal and fish oil. Plant proteins represent a suitable protein alternative to fish meal and are increasingly being used in fish feed. In this study, we examined the transcriptional response of Atlantic salmon (Salmo salar to a high marine protein (MP or low fishmeal, higher plant protein replacement diet (PP, formulated to the same nutritional specification within previously determined acceptable maximum levels of individual plant feed materials. Results After 77 days of feeding the fish in both groups doubled in weight, however neither growth performance, feed efficiency, condition factor nor organ indices were significantly different. Assessment of histopathological changes in the heart, intestine or liver did not reveal any negative effects of the PP diet. Transcriptomic analysis was performed in mid intestine, liver and skeletal muscle, using an Atlantic salmon oligonucleotide microarray (Salar_2, Agilent 4x44K. The dietary comparison revealed large alteration in gene expression in all the tissues studied between fish on the two diets. Gene ontology analysis showed, in the mid intestine of fish fed PP, higher expression of genes involved in enteritis, protein and energy metabolism, mitochondrial activity/kinases and transport, and a lower expression of genes involved in cell proliferation and apoptosis compared to fish fed MP. The liver of fish fed PP showed a lower expression of immune response genes but a higher expression of cell proliferation and apoptosis processes that may lead to cell reorganization in this tissue. The skeletal muscle of fish fed PP vs MP was characterized by a suppression of processes including immune response, energy and protein metabolism, cell proliferation and apoptosis which may reflect a more energy efficient tissue. Conclusions The PP

Assessment of a land-locked Atlantic salmon (Salmo salar L.) population as a potential genetic resource with a focus on long-chain polyunsaturated fatty acid biosynthesis.

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Betancor, M B; Olsen, R E; Solstorm, D; Skulstad, O F; Tocher, D R

2016-03-01

The natural food for Atlantic salmon (Salmo salar) in freshwater has relatively lower levels of omega-3 (n-3) long-chain polyunsaturated fatty acids (LC-PUFA) than found in prey for post-smolt salmon in seawater. Land-locked salmon such as the Gullspång population feed exclusively on freshwater type lipids during its entire life cycle, a successful adaptation derived from divergent evolution. Studying land-locked populations may provide insights into the molecular and genetic control mechanisms that determine and regulate n-3 LC-PUFA biosynthesis and retention in Atlantic salmon. A two factorial study was performed comparing land-locked and farmed salmon parr fed diets formulated with fish or rapeseed oil for 8 weeks. The land-locked parr had higher capacity to synthesise n-3 LC-PUFA as indicated by higher expression and activity of desaturase and elongase enzymes. The data suggested that the land-locked salmon had reduced sensitivity to dietary fatty acid composition and that dietary docosahexaenoic acid (DHA) did not appear to suppress expression of LC-PUFA biosynthetic genes or activity of the biosynthesis pathway, probably an evolutionary adaptation to a natural diet lower in DHA. Increased biosynthetic activity did not translate to enhanced n-3 LC-PUFA contents in the flesh and diet was the only factor affecting this parameter. Additionally, high lipogenic and glycolytic potentials were found in land-locked salmon, together with decreased lipolysis which in turn could indicate increased use of carbohydrates as an energy source and a sparing of lipid. Copyright © 2015 Elsevier B.V. All rights reserved.

Transgene and immune gene expression following intramuscular injection of Atlantic salmon (Salmo salar L.) with DNA-releasing PLGA nano- and microparticles.

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Hølvold, Linn Benjaminsen; Fredriksen, Børge N; Bøgwald, Jarl; Dalmo, Roy A

2013-09-01

The use of poly-(D,L-lactic-co-glycolic) acid (PLGA) particles as carriers for DNA delivery has received considerable attention in mammalian studies. DNA vaccination of fish has been shown to elicit durable transgene expression, but no reports exist on intramuscular administration of PLGA-encapsulated plasmid DNA (pDNA). We injected Atlantic salmon (Salmo salar L.) intramuscularly with a plasmid vector containing a luciferase (Photinus pyralis) reporter gene as a) naked pDNA, b) encapsulated into PLGA nano- (~320 nm) (NP) or microparticles (~4 μm) (MP), c) in an oil-based formulation, or with empty particles of both sizes. The ability of the different pDNA-treatments to induce transgene expression was analyzed through a 70-day experimental period. Anatomical distribution patterns and depot effects were determined by tracking isotope labeled pDNA. Muscle, head kidney and spleen from all treatment groups were analyzed for proinflammatory cytokines (TNF-α, IL-1β), antiviral genes (IFN-α, Mx) and cytotoxic T-cell markers (CD8, Eomes) at mRNA transcription levels at days 1, 2, 4 and 7. Histopathological examinations were performed on injection site samples from days 2, 7 and 30. Injection of either naked pDNA or the oil-formulation was superior to particle treatments for inducing transgene expression at early time-points. Empty particles of both sizes were able to induce proinflammatory immune responses as well as degenerative and inflammatory pathology at the injection site. Microparticles demonstrated injection site depots and an inflammatory pathology comparable to the oil-based formulation. In comparison, the distribution of NP-encapsulated pDNA resembled that of naked pDNA, although encapsulation into NPs significantly elevated the expression of antiviral genes in all tissues. Together the results indicate that while naked pDNA is most efficient for inducing transgene expression, the encapsulation of pDNA into NPs up-regulates antiviral responses that could be

Replacement of dietary soy- with air classified faba bean protein concentrate alters the hepatic transcriptome in Atlantic salmon (Salmo salar) parr.

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De Santis, Christian; Crampton, Viv O; Bicskei, Beatrix; Tocher, Douglas R

2015-12-01

The production of carnivorous fish such as Atlantic salmon (Salmo salar) is dependent on the availability of high quality proteins for feed formulations. For a number of nutritional, strategic and economic reasons, the use of plant proteins has steadily increased over the years, however a major limitation is associated with the presence of anti-nutritional factors and the nutritional profile of the protein concentrate. Investigating novel raw materials involves understanding the physiological consequences associated with the dietary inclusion of protein concentrates. The primary aim of the present study was to assess the metabolic response of salmon to increasing inclusion of air-classified faba bean protein concentrate (BPC) in feeds as a replacement for soy protein concentrate (SPC). Specifically, we tested treatments with identical contents of fishmeal (222.4gkg(-1)) and progressively higher inclusion of BPC (0gkg(-1), 111.8gkg(-1), 223.6gkg(-1), 335.4gkg(-1), 447.2gkg(-1)) substituting SPC. This study demonstrated a dose-dependent metabolic response to a plant ingredient and was the first to compare the nutrigenomic transcriptional responses after substitution of terrestrial feed ingredients such as BPC and SPC without withdrawal of marine ingredients. It was found that after eight weeks a major physiological response in liver was only evident above 335.4gkg(-1) BPC and included decreased expression of metabolic pathways, and increased expression of genes regulating transcription and translation processes and the innate immune response. Furthermore, we showed that the nutritional stress caused by BPC resembled, at least at hepatic transcriptional level, that caused by soybean meal (included as a positive control in our experimental design). The outcomes of the present study suggested that Atlantic salmon parr might efficiently utilize moderate substitution of dietary SPC with BPC, with the optimum inclusion level being around 120gkg(-1)in the type of feeds

Effects of dehulling, steam-cooking and microwave-irradiation on digestive value of white lupin (Lupinus albus) seed meal for rainbow trout (Oncorhynchus mykiss) and Atlantic salmon (Salmo salar).

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Saez, Patricio; Borquez, Aliro; Dantagnan, Patricio; Hernández, Adrián

2015-01-01

A digestibility trial was conducted to assess the effect of dehulling, steam-cooking and microwave-irradiation on the apparent digestibility of nutrients in white lupin (Lupinus albus) seed meal when fed to rainbow trout (Oncorhynchus mykiss) and Atlantic salmon (Salmo salar). Six ingredients, whole lupin seed meal (LSM), dehulled LSM, dehulled LSM steam-cooked for 15 or 45 min (SC15 and SC45, respectively) and LSM microwave-irradiated at 375 or 750 W (MW375 and MW750, respectively), were evaluated for digestibility of dry matter, crude protein (CP), lipids, nitrogen-free extractives (NFE) and gross energy (GE). The diet-substitution approach was used (70% reference diet + 30% test ingredient). Faeces from each tank were collected using a settlement column. Dehulled LSM showed higher levels of proximate components (except for NFE and crude fibre), GE and phosphorus in comparison to whole LSM. Furthermore, SC15, SC45, MW375 and MW750 showed slight variations of chemical composition in comparison to dehulled LSM. Results from the digestibility trial indicated that dehulled LSM, SC15, SC45 and MW375 are suitable processing methods for the improvement of nutrients' apparent digestibility coefficient (ADC) in whole LSM. MW750 showed a lower ADC of nutrients (except for CP and lipids for rainbow trout) in comparison with MW350 for rainbow trout and Atlantic salmon, suggesting a heat damage of the ingredient when microwave-irradiation exceeded 350 W.

Terrestrial liming to promote Atlantic Salmon recovery in Nova Scotia - approaches needed and knowledge gained after a trial application

Science.gov (United States)

Sterling, S. M.; Angelidis, C.; Armstrong, M.; Biagi, K. M.; Clair, T. A.; Jackson, N.; Breen, A.

2014-09-01

Populations of Atlantic salmon (Salmo salar) in Southwest Nova Scotia (SWNS) have plummeted since the 1980s. Acidification is considered a main threat to this population. The lakes and streams of SWNS were among the most heavily acidified in North America during the last century and calcium levels are predicted to continue to fall in coming decades. One of the most promising mitigation options to reduce the risk of extirpation of the SWNS Salmo salar is terrestrial liming; however, both the chemistry of SWNS rivers, and effective strategies for terrestrial liming in SWNS are poorly understood. Here we have launched the first terrestrial liming study in Nova Scotia, employing a test hydrologic source area liming strategy in a 5 ha experimental catchment in SWNS, Maria Brook; we apply an average local application rate of 13 t ha-1 to 10% of the 47 ha catchment. We employ high frequency stream monitoring to complement grab sampling to identify which constituents pose a threat to Salmo salar and to identify strategies for larger scale terrestrial liming that would fit the local conditions. Results indicate that the water chemistry conditions are currently at toxic levels for Salmo salar throughout the year, with levels of ionic aluminium exceeding toxic thresholds almost 100% of the time. The stream chemistry in Maria Brook is remarkably similar to pre-recovery conditions in other heavily acidified watersheds, such as Birkenes in Norway. Our results support the hypothesis that there has been no recovery from acidification in SWNS. Results from the first year of post-liming do not show an improvement in stream chemistry levels, and further lime application is needed to improve the water chemistry conditions to needed levels for the recovery of Salmo salar.

Acyl-coenzyme A oxidases 1 and 3 in brown trout (Salmo trutta f. fario): Can peroxisomal fatty acid β-oxidation be regulated by estrogen signaling?

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Madureira, Tânia Vieira; Castro, L Filipe C; Rocha, Eduardo

2016-02-01

Acyl-coenzyme A oxidases 1 (Acox1) and 3 (Acox3) are key enzymes in the regulation of lipid homeostasis. Endogenous and exogenous factors can disrupt their normal expression/activity. This study presents for the first time the isolation and characterization of Acox1 and Acox3 in brown trout (Salmo trutta f. fario). Additionally, as previous data point to the existence of a cross-talk between two nuclear receptors, namely peroxisome proliferator-activated receptors and estrogen receptors, it was here evaluated after in vitro exposures of trout hepatocytes the interference caused by ethynylestradiol in the mRNA levels of an inducible (by peroxisome proliferators) and a non-inducible oxidase. The isolated Acox1 and Acox3 show high levels of sequence conservation compared to those of other teleosts. Additionally, it was found that Acox1 has two alternative splicing isoforms, corresponding to 3I and 3II isoforms of exon 3 splicing variants. Both isoforms display tissue specificity, with Acox1-3II presenting a more ubiquitous expression in comparison with Acox1-3I. Acox3 was expressed in almost all brown trout tissues. According to real-time PCR data, the highest estrogenic stimulus was able to cause a down-regulation of Acox1 and an up-regulation of Acox3. So, for Acox1 we found a negative association between an estrogenic input and a directly activated PPARα target gene. In conclusion, changes in hormonal estrogenic stimulus may impact the mobilization of hepatic lipids to the gonads, with ultimate consequences in reproduction. Further studies using in vivo assays will be fundamental to clarify these issues.

EFFECT OF NON-ESSENTIAL ELEMENTS (MERCURY. ARSENIC ON SALMONIDS (SALMONIDAE (REVIEW

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І. Hrytsyniak

2015-09-01

Full Text Available Purpose. The problem of water ecosystem pollution with heavy metals achieved great actuality during recent years, both because of their significant distribution in environment, and wide spectrum of their toxic effects on fish organism. Much attention in modern scientific literature is given to the problem of the effects of heavy metals, including mercury and arsenic, on fish organism. However, investigations in this field are conducted mainly on cyprinids, while physiological and biochemical mechanisms of the effects of heavy metals on salmonids are less studied. According to this, the studies of the sources of heavy metals in water ecosystems, peculiarities of their action in salmonid organism on subcellular, cellular, tissue and organ levels, species and age-related peculiarities of the effects of heavy metals are of great scientific and practical importance. The purpose of this work is to review the mentioned problems. Findings. The work characterizes the effects of mercury and arsenic on salmonids on subcellular, cellular, tissue and organ levels. The article contains characteristic of conditions, under which toxic or lethal action of the mentioned xenobiotics on different species of salmonids was observed. Originality. The paper summarizes literature data concerning the effect of mercury and arsenic on salmonids. Attention is accented on the sources of the mentioned pollutants in surface waters, physiological and biochemical mechanisms of their effects on salmonids, and on factors, which determine the level of their toxicity. Lethal concentrations of mercury and arsenic to salmonids, depending on experiment duration, species and age-related peculiarities are presented. Practical value. Data presented in the review can be used for the explanation of physiological and biochemical mechanisms of the adaptation of salmonids to surface water pollution with heavy metals, diagnostics of fish pathologies caused by toxic effects of mercury and arsenic, and complex assessment of factors, which influence the toxicity level of the mentioned pollutants in environment.

APPLICATION OF SALMONIDS (SALMONIDAE N THE BIOMONITORING OF AQUATIC ENVIRONMENT (REVIEW

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D. Yanovych

2016-03-01

Full Text Available Purpose. Due to the pollution of fisheries water bodies by industrial and agricultural waste waters, as well as by xenobiotics coming from other sources, taking into account a pridictable increase in the amounts of such effluents in the short and long terms, the problems related to the study of the effects of the pollutants of different nature and origin on aquatic organisms, especially fish, as well as a prediction of possible adverse consequences on aquatic ecosystems, becomes particularly important. The aim of our work was an analysis and synthesis of existing literature data concerning the indication in the biomonitoring of aquatic environments based on biological markers of salmonids as highly sensitive objects of fish fauna to external factors. Findings. The review summarizes and systematizes the data concerning the use of salmonids in biomonitoring studies. Furthermore, we highlighted and characterized the specificity of bioindication parameters of the aquatic environment state, such as the biochemical, genetic, physiological, morphological, histopathological, behavioral and population markers and noted the effects of hydroecosystem ecotoxication on different levels of biological organization (cell, individual, population, fish community. We also described the possibility of biological monitoring based on saprobic indexes identified for indicator species belonging to salmonids. Originality. In the article describes the structure, pros and cons of the use of specific biomarkers of individual salmonid fish and their populations for assessing the ecological status of aquatic environments. Practical value. The data given in the article can be used to improve the system of the ecological monitoring of aquatic environments by extending the range of indicator indices with organism and population biomarkers of highly sensitive salmonid species.

Efficacité d'un exutoire de dévalaison pour smolts de saumon atlantique (Salmo salar L.) et comportement des poissons au niveau de l'aménagement hydroélectrique de Bedous sur le gave d'Aspe étudiés par la technique de marquage-recapture et par radiotélémétrie

OpenAIRE

CHANSEAU M.; LARINIER M.; TRAVADE F.

1999-01-01

Deux expérimentations ont été conduites en 1995 et 1998 au niveau de la prise d'eau de l'aménagement hydroélectrique de Bedous sur le Gave d'Aspe afin de tester l'efficacité d'un exutoire de dévalaison pour smolts de saumon atlantique (Salmo salar L.). Le dispositif de dévalaison est situé en rive droite à proximité immédiate du plan des grilles. Le débit moyen alimentant l'exutoire a varié au cours de l'étude de 0,4 m3/s à 1,2 m3/s ce qui correspond à 1,6 % à 4,3 % du débit turbiné. Lefficac...

Forest-stream linkages: effects of terrestrial invertebrate input and light on diet and growth of brown trout (Salmo trutta in a boreal forest stream.

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Tibor Erős

Full Text Available Subsidies of energy and material from the riparian zone have large impacts on recipient stream habitats. Human-induced changes, such as deforestation, may profoundly affect these pathways. However, the strength of individual factors on stream ecosystems is poorly understood since the factors involved often interact in complex ways. We isolated two of these factors, manipulating the flux of terrestrial input and the intensity of light in a 2×2 factorial design, where we followed the growth and diet of two size-classes of brown trout (Salmo trutta and the development of periphyton, grazer macroinvertebrates, terrestrial invertebrate inputs, and drift in twelve 20 m long enclosed stream reaches in a five-month-long experiment in a boreal coniferous forest stream. We found that light intensity, which was artificially increased 2.5 times above ambient levels, had an effect on grazer density, but no detectable effect on chlorophyll a biomass. We also found a seasonal effect on the amount of drift and that the reduction of terrestrial prey input, accomplished by covering enclosures with transparent plastic, had a negative impact on the amount of terrestrial invertebrates in the drift. Further, trout growth was strongly seasonal and followed the same pattern as drift biomass, and the reduction of terrestrial prey input had a negative effect on trout growth. Diet analysis was consistent with growth differences, showing that trout in open enclosures consumed relatively more terrestrial prey in summer than trout living in covered enclosures. We also predicted ontogenetic differences in the diet and growth of old and young trout, where we expected old fish to be more affected by the terrestrial prey reduction, but we found little evidence of ontogenetic differences. Overall, our results showed that reduced terrestrial prey inputs, as would be expected from forest harvesting, shaped differences in the growth and diet of the top predator, brown trout.

La compétition interspécifique entre la truite commune (Salmo trutta L. et la truite arc-en-ciel (Oncorhynchus Mykiss Walbaum : influence sur les modèles d'habitat

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BARAN P.

1995-04-01

Full Text Available L'influence de la compétition interspécifique sur l'occupation de l'habitat physique du ruisseau d'Estibère a été étudiée sur deux populations de truite arc-en-ciel (Oncorhynchus mykiss, vivant respectivement en allopatrie et en sympatrie avec une population de truite commune (Salmo trutta L.. Le taux d'occupation de la Surface Pondérée Utile (SPU calculée par la méthode des microhabitats (BOVEE, 1982 est significativement supérieur (t de Student, p < 0.05 pour la population allopatrique de truite arc-en-ciel par rapport à la population sympatrique. La surface d'abris, la pente et le taux d'occupation de la SPU par les truites communes permettent d'expliquer 77 % de la variation d'occupation de l'habitat physique par les adultes de truites arc-en-ciel. Pour les truites communes, la surface d'abris explique à elle seule, 81 % de la variation du taux d'occupation de l'habitat par les adultes. Selon l'espèce et le stade de développement considéré, la compétition interspécifique peut être un élément déterminant dans l'occupation de l'habitat physique potentiel.

Identification of a low digestibility δ-Conglutin in yellow lupin (Lupinus luteus L.) seed meal for atlantic salmon (Salmo salar L.) by coupling 2D-PAGE and mass spectrometry.

Science.gov (United States)

Ogura, Takahiro; Hernández, Adrián; Aizawa, Tomoko; Ogihara, Jun; Sunairi, Michio; Alcaino, Javier; Salvo-Garrido, Haroldo; Maureira-Butler, Iván J

2013-01-01

The need of quality protein in the aquaculture sector has forced the incorporation of alternative plant proteins into feeding diets. However, most plant proteins show lower digestibility levels than fish meal proteins, especially in carnivorous fishes. Manipulation of protein content by plant breeding can improve the digestibility rate of plant proteins in fish, but the identification of low digestibility proteins is essential. A reduction of low digestibility proteins will not only increase feed efficiency, but also reduce water pollution. Little is known about specific digestible protein profiles and/or molecular identification of more bioavailable plant proteins in fish diets. In this study, we identified low digestibility L. luteus seed proteins using Atlantic salmon (Salmo salar) crude digestive enzymes in an in vitro assay. Low digestibility proteins were identified by comparing SDS-PAGE banding profiles of digested and non-digested lupin seed proteins. Gel image analysis detected a major 12 kDa protein band in both lupin meal and protein isolate digested products. The 12 kDa was confirmed by 2D-PAGE gels and the extracted protein was analyzed with an ion trap mass spectrometer in tandem mass mode. The MS/MS data showed that the 12 kDa low digestibility protein was a large chain δconglutin, a common seed storage protein of yellow lupin. Comparison of the protein band profiles between lupin meal and protein isolates showed that the isolatation process did not affect the low digestibility of the 12 kDa protein.

Identification of a Low Digestibility δ-Conglutin in Yellow Lupin (Lupinus luteus L.) Seed Meal for Atlantic Salmon (Salmo salar L.) by Coupling 2D-PAGE and Mass Spectrometry

Science.gov (United States)

Ogura, Takahiro; Hernández, Adrián; Aizawa, Tomoko; Ogihara, Jun; Sunairi, Michio; Alcaino, Javier; Salvo-Garrido, Haroldo; Maureira-Butler, Iván J.

2013-01-01

The need of quality protein in the aquaculture sector has forced the incorporation of alternative plant proteins into feeding diets. However, most plant proteins show lower digestibility levels than fish meal proteins, especially in carnivorous fishes. Manipulation of protein content by plant breeding can improve the digestibility rate of plant proteins in fish, but the identification of low digestibility proteins is essential. A reduction of low digestibility proteins will not only increase feed efficiency, but also reduce water pollution. Little is known about specific digestible protein profiles and/or molecular identification of more bioavailable plant proteins in fish diets. In this study, we identified low digestibility L. luteus seed proteins using Atlantic salmon (Salmo salar) crude digestive enzymes in an in vitro assay. Low digestibility proteins were identified by comparing SDS-PAGE banding profiles of digested and non-digested lupin seed proteins. Gel image analysis detected a major 12 kDa protein band in both lupin meal and protein isolate digested products. The 12 kDa was confirmed by 2D-PAGE gels and the extracted protein was analyzed with an ion trap mass spectrometer in tandem mass mode. The MS/MS data showed that the 12 kDa low digestibility protein was a large chain δconglutin, a common seed storage protein of yellow lupin. Comparison of the protein band profiles between lupin meal and protein isolates showed that the isolatation process did not affect the low digestibility of the 12 kDa protein. PMID:24278278

Partial nucleotide sequences, and routine typing by polymerase chain reaction-restriction fragment length polymorphism, of the brown trout (Salmo trutta) lactate dehydrogenase, LDH-C1*90 and *100 alleles.

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McMeel, O M; Hoey, E M; Ferguson, A

2001-01-01

The cDNA nucleotide sequences of the lactate dehydrogenase alleles LDH-C1*90 and *100 of brown trout (Salmo trutta) were found to differ at position 308 where an A is present in the *100 allele but a G is present in the *90 allele. This base substitution results in an amino acid change from aspartic acid at position 82 in the LDH-C1 100 allozyme to a glycine in the 90 allozyme. Since aspartic acid has a net negative charge whilst glycine is uncharged, this is consistent with the electrophoretic observation that the LDH-C1 100 allozyme has a more anodal mobility relative to the LDH-C1 90 allozyme. Based on alignment of the cDNA sequence with the mouse genomic sequence, a local primer set was designed, incorporating the variable position, and was found to give very good amplification with brown trout genomic DNA. Sequencing of this fragment confirmed the difference in both homozygous and heterozygous individuals. Digestion of the polymerase chain reaction products with BslI, a restriction enzyme specific for the site difference, gave one, two and three fragments for the two homozygotes and the heterozygote, respectively, following electrophoretic separation. This provides a DNA-based means of routine screening of the highly informative LDH-C1* polymorphism in brown trout population genetic studies. Primer sets presented could be used to sequence cDNA of other LDH* genes of brown trout and other species.

Activity of metabolic enzymes and muscle-specific gene expression in parr and smolts Atlantic salmon Salmo salar L. of different age groups.

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Churova, Maria V; Meshcheryakova, Olga V; Veselov, Aleksey E; Efremov, Denis A; Nemova, Nina N

2017-08-01

This study was conducted to characterize the energy metabolism level and the features of muscle growth regulation during the development of Atlantic salmon (Salmo salar) inhabiting the Indera River (Kola Peninsula, Russia). The activities of aerobic and anaerobic enzymes (cytochrome c oxidase and lactate dehydrogenase) and carbohydrate metabolism enzymes (glucose-6-phosphate dehydrogenase, glycerol-3-phosphate dehydrogenase, and aldolase) were measured in muscle and liver tissue. Gene expression levels of myosin heavy chain (MyHC), myostatin (MSTN-1a), and myogenic regulatory factors (MRFs-MyoD1a, MyoD1b, MyoD1c, Myf5, myogenin) were measured in the white muscles of salmon parr of ages 0+, 1+, 2+, and 3+ and smolts of ages 2+ and 3+. Multidirectional changes in the activity of enzymes involved in aerobic and anaerobic energy metabolism with age were shown in the white muscles of the parr. The cytochrome c oxidase activity was higher in muscles of underyearlings (0+) and yearlings (1+) and decreased in 2+ and 3+ age groups. The activity of lactate dehydrogenase, in contrast, increased with age. The patterns of changes in expression levels of MyoD1a, MyoD1b, myogenin, MyHC, and MSTN-1a at different ages of the parr were similar. Particularly, the expression of these genes peaked in the yearling parr (1+) and then decreased in elder groups. The differences were revealed in parameters studied between the parr and smolts. The level of aerobic and anaerobic metabolism enzyme activities was higher in the white muscles of smolts than in parr. The activity of carbohydrate metabolism enzymes was decreased in the smolts' livers. The expression levels of MyHC, MyoD1a, MyoD1b, and myogenin were lower in smolts at age 2+ compared to parr. These findings expand our knowledge of age-related and stage-related features of energy metabolism and muscle development regulation in young Atlantic salmon in their natural habitat. The results might be used for monitoring of the salmon

Dietary peppermint (Mentha piperita) extracts promote growth performance and increase the main humoral immune parameters (both at mucosal and systemic level) of Caspian brown trout (Salmo trutta caspius Kessler, 1877).

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Adel, Milad; Safari, Reza; Pourgholam, Reza; Zorriehzahra, Jalil; Esteban, Maria Ángeles

2015-11-01

The effects of dietary administration of peppermint (Mentha piperita L.) on Caspian brown trout fish (Salmo trutta caspius) were studied. Fish were divided into 4 groups before being fed diets supplemented with 0% (control), 1%, 2% and 3% of peppermint extracts for 8 weeks. Dose-dependent increases in growth, immune (both in skin mucus and blood serum) and hematological parameters (number of white cells, hematocrit and hemoglobin content), as well as in amylase activity and in the number of lactic acid bacteria on intestine were recorded in fish fed supplemented diets compared to control fish. However, the dietary peppermint supplements have different effects on the number of blood leucocytes depending on the leukocyte cell type. While no significant differences were observed in the number of blood monocytes and eosinophils, the number of lymphocytes was decreased, respectively, on fish fed peppermint enriched diets, respect to the values found in control fish. Furthermore, dietary peppermint supplements have no significant effect on blood biochemical parameters, enzymatic activities of liver determined in serum and total viable aerobic bacterial count on intestine of Caspian brown trout. Present results support that dietary administration of peppermint promotes growth performance and increases the main humoral immune parameters (both at mucosal and systemic level) and the number of the endogenous lactic acid bacteria of Caspian brown trout. This study underlying several positive effects of dietary administration of peppermint to farmed fish. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mineralization of the vertebral bodies in Atlantic salmon (Salmo salar L.) is initiated segmentally in the form of hydroxyapatite crystal accretions in the notochord sheath.

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Wang, Shou; Kryvi, Harald; Grotmol, Sindre; Wargelius, Anna; Krossøy, Christel; Epple, Mattias; Neues, Frank; Furmanek, Tomasz; Totland, Geir K

2013-08-01

We performed a sequential morphological and molecular biological study of the development of the vertebral bodies in Atlantic salmon (Salmo salar L.). Mineralization starts in separate bony elements which fuse to form complete segmental rings within the notochord sheath. The nucleation and growth of hydroxyapatite crystals in both the lamellar type II collagen matrix of the notochord sheath and the lamellar type I collagen matrix derived from the sclerotome, were highly similar. In both matrices the hydroxyapatite crystals nucleate and accrete on the surface of the collagen fibrils rather than inside the fibrils, a process that may be controlled by a template imposed by the collagen fibrils. Apatite crystal growth starts with the formation of small plate-like structures, about 5 nm thick, that gradually grow and aggregate to form extensive multi-branched crystal arborizations, resembling dendritic growth. The hydroxyapatite crystals are always oriented parallel to the long axis of the collagen fibrils, and the lamellar collagen matrices provide oriented support for crystal growth. We demonstrate here for the first time by means of synchroton radiation based on X-ray diffraction that the chordacentra contain hydroxyapatite. We employed quantitative real-time PCR to study the expression of key signalling molecule transcripts expressed in the cellular core of the notochord. The results indicate that the notochord not only produces and maintains the notochord sheath but also expresses factors known to regulate skeletogenesis: sonic hedgehog (shh), indian hedgehog homolog b (ihhb), parathyroid hormone 1 receptor (pth1r) and transforming growth factor beta 1 (tgfb1). In conclusion, our study provides evidence for the process of vertebral body development in teleost fishes, which is initially orchestrated by the notochord. © 2013 Anatomical Society.

Baseline identification in stable -isotope studies of temperate lotic systems and implications for calculated trophic positions

DEFF Research Database (Denmark)

Kristensen, Peter Brinkmann; Riis, Tenna; Dylmer, Hans Erik

2016-01-01

of two common fish species (three-spined stickleback, Gasterosteus aculeatus, and brown trout Salmo trutta) differed markedly depending on the baseline chosen. The estimated trophic position was lowest when based on Baetidae and highest when using Simuliidae. The trophic position of Gasterosteus...... aculeatus was independent of land use (proxy used=%nature) when based on Gammarus pulex and Simuliidae, and the trophic position of Salmo trutta was independent of land use when based on Simuliidae only. The trophic position estimates based on Baetidae and mean primary consumers correlated with %nature...

Small functional If current in sinoatrial pacemaker cells of the brown trout (Salmo trutta fario) heart despite strong expression of HCN channel transcripts.

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Hassinen, Minna; Haverinen, Jaakko; Vornanen, Matti

2017-12-01

Funny current ( I f ), formed by hyperpolarization-activated cyclic nucleotide-gated channels (HCN channels), is supposed to be crucial for the membrane clock regulating the cardiac pacemaker mechanism. We examined the presence and activity of HCN channels in the brown trout ( Salmo trutta fario ) sinoatrial (SA) pacemaker cells and their putative role in heart rate ( f H ) regulation. Six HCN transcripts (HCN1, HCN2a, HCN2ba, HCN2bb, HCN3, and HCN4) were expressed in the brown trout heart. The total HCN transcript abundance was 4.0 and 4.9 times higher in SA pacemaker tissue than in atrium and ventricle, respectively. In the SA pacemaker, HCN3 and HCN4 were the main isoforms representing 35.8 ± 2.7 and 25.0 ± 1.5%, respectively, of the total HCN transcripts. Only a small I f with a mean current density of -1.2 ± 0.37 pA/pF at -140 mV was found in 4 pacemaker cells out of 16 spontaneously beating cells examined, despite the optimization of recording conditions for I f activity. I f was not found in any of the 24 atrial myocytes and 21 ventricular myocytes examined. HCN4 coexpressed with the MinK-related peptide 1 (MiRP1) β-subunit in CHO cells generated large I f currents. In contrast, HCN3 (+MiRP1) failed to produce I f in the same expression system. Cs + (2 mM), which blocked 84 ± 12% of the native I f , reversibly reduced f H 19.2 ± 3.6% of the excised multicellular pacemaker tissue from 53 ± 5 to 44 ± 5 beats/min ( P brown trout heart is largely independent on I f . Copyright © 2017 the American Physiological Society.

The effects of chronic cadmium exposure on repeat swimming performance and anaerobic metabolism in brown trout (Salmo trutta) and lake whitefish (Coregonus clupeaformis).

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Cunningham, Jessie L; McGeer, James C

2016-04-01

This study investigates the effect of chronic Cd exposure on the ability to perform repeat swim challenges in brown trout (Salmo trutta) and lake whitefish (Coregonus clupeaformis). Fish were exposed to waterborne Cd (18nM) in moderately hard water (120mgL(-1) CaCO3) for 30 days. This level of exposure has been shown to cause sublethal physiological disruption and acclimation responses but no impairment of sustained swimming capacity (Ucrit) in single swim challenges. Swim trials were done over the course of the exposure and each one consisted of an initial swim to 85% of the Ucrit of control fish, a 30min recovery period and finally a second swim challenge to determine Ucrit. Plasma and tissue samples were collected before and after each of the swim periods. As expected from previous studies, Cd exposure resulted in significant accumulation of Cd in gills, liver and kidney but not in white muscle. Exposure also induced a loss of plasma Ca followed by subsequent recovery (in lake whitefish but not brown trout) with few mortalities (100% survival for lake whitefish and 93% for brown trout). Both control and exposed fish swam to 85% of the single swim Ucrit and no differences in performance were seen. The Ucrit of unexposed controls in the second swim challenges were not different from the single swim Ucrit. However, second swim performance was significantly reduced in Cd exposed fish, particularly after a week of exposure where 31% and 38% reductions were observed for brown trout and lake whitefish respectively. Swimming to 85% Ucrit resulted in metabolic expenditure with little recovery after 30min. Few differences were observed between control and Cd exposed fish with the exception of a reduction in resting white muscle ATP stores of Cd exposed fish after 1 week of exposure. The results show that chronic sublethal Cd exposure results in an impairment of swimming ability in repeat swim challenges but this impairment is generally not related to metabolic processes

Identification of a low digestibility δ-Conglutin in yellow lupin (Lupinus luteus L. seed meal for atlantic salmon (Salmo salar L. by coupling 2D-PAGE and mass spectrometry.

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Takahiro Ogura

Full Text Available The need of quality protein in the aquaculture sector has forced the incorporation of alternative plant proteins into feeding diets. However, most plant proteins show lower digestibility levels than fish meal proteins, especially in carnivorous fishes. Manipulation of protein content by plant breeding can improve the digestibility rate of plant proteins in fish, but the identification of low digestibility proteins is essential. A reduction of low digestibility proteins will not only increase feed efficiency, but also reduce water pollution. Little is known about specific digestible protein profiles and/or molecular identification of more bioavailable plant proteins in fish diets. In this study, we identified low digestibility L. luteus seed proteins using Atlantic salmon (Salmo salar crude digestive enzymes in an in vitro assay. Low digestibility proteins were identified by comparing SDS-PAGE banding profiles of digested and non-digested lupin seed proteins. Gel image analysis detected a major 12 kDa protein band in both lupin meal and protein isolate digested products. The 12 kDa was confirmed by 2D-PAGE gels and the extracted protein was analyzed with an ion trap mass spectrometer in tandem mass mode. The MS/MS data showed that the 12 kDa low digestibility protein was a large chain δconglutin, a common seed storage protein of yellow lupin. Comparison of the protein band profiles between lupin meal and protein isolates showed that the isolatation process did not affect the low digestibility of the 12 kDa protein.

Influence of Fishmeal-Free Diets on Microbial Communities in Atlantic Salmon (Salmo salar) Recirculation Aquaculture Systems.

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Schmidt, Victor; Amaral-Zettler, Linda; Davidson, John; Summerfelt, Steven; Good, Christopher

2016-08-01

Reliance on fishmeal as a primary protein source is among the chief economic and environmental concerns in aquaculture today. Fishmeal-based feeds often require harvest from wild fish stocks, placing pressure on natural ecosystems and causing price instability. Alternative diet formulations without the use of fishmeal provide a potential solution to this challenge. Although the impact of alternative diets on fish performance, intestinal inflammation, palatability, and gut microbiota has been a topic of recent interest, less is known about how alternative feeds impact the aquaculture environment as a whole. The recent focus on recirculating aquaculture systems (RAS) and the closed-containment approach to raising food fish highlights the need to maintain stable environmental and microbiological conditions within a farm environment. Microbial stability in RAS biofilters is particularly important, given its role in nutrient processing and water quality in these closed systems. If and how the impacts of alternative feeds on microbial communities in fish translate into changes to the biofilters are not known. We tested the influence of a fishmeal-free diet on the microbial communities in RAS water, biofilters, and salmon microbiomes using high-throughput 16S rRNA gene V6 hypervariable region amplicon sequencing. We grew Atlantic salmon (Salmo salar) to market size in six replicate RAS tanks, three with traditional fishmeal diets and three with alternative-protein, fishmeal-free diets. We sampled intestines and gills from market-ready adult fish, water, and biofilter medium in each corresponding RAS unit. Our results provide data on how fish diet influences the RAS environment and corroborate previous findings that diet has a clear influence on the microbiome structure of the salmon intestine, particularly within the order Lactobacillales (lactic acid bacteria). We conclude that the strong stability of taxa likely involved in water quality processing regardless of diet (e

Comparison of vaccine efficacy for different antigen delivery systems for infectious pancreatic necrosis virus vaccines in Atlantic salmon (Salmo salar L.) in a cohabitation challenge model.

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Munang'andu, Hetron M; Fredriksen, Børge N; Mutoloki, Stephen; Brudeseth, Bjørn; Kuo, Tsun-Yung; Marjara, Inderjit S; Dalmo, Roy A; Evensen, Øystein

2012-06-08

Two strains of IPNV made by reverse genetics on the Norwegian Sp strain NVI-015 (GenBank AY379740) backbone encoding the virulent (T(217)A(221)) and avirulent (P(217)T(221)) motifs were used to prepare inactivated whole virus (IWV), nanoparticle vaccines with whole virus, Escherichia coli subunit encoding truncated VP2-TA and VP2-PT, VP2-TA and VP2-PT fusion antigens with putative translocating domains of Pseudomonas aeruginosa exotoxin, and plasmid DNA encoding segment A of the TA strain. Post challenge survival percentages (PCSP) showed that IWV vaccines conferred highest protection (PCSP=42-53) while nanoparticle, sub-unit recombinant and DNA vaccines fell short of the IWV vaccines in Atlantic salmon (Salmo salar L.) postsmolts challenged with the highly virulent Sp strain NVI-015 (TA strain) of IPNV after 560 degree days post vaccination. Antibody levels induced by these vaccines did not show antigenic differences between the virulent and avirulent motifs for vaccines made with the same antigen dose and delivery system after 8 weeks post vaccination. Our findings show that fish vaccinated with less potent vaccines comprising of nanoparticle, DNA and recombinant vaccines got infected much earlier and yielded to higher infection rates than fish vaccinated with IWV vaccines that were highly potent. Ability of the virulent (T(217)A(221)) and avirulent (P(217)T(221)) motifs to limit establishment of infection showed equal protection for vaccines made of the same antigen dose and delivery systems. Prevention of tissue damage linked to viral infection was eminent in the more potent vaccines than the less protective ones. Hence, there still remains the challenge of developing highly efficacious vaccines with the ability to eliminate the post challenge carrier state in IPNV vaccinology. Copyright © 2012 Elsevier Ltd. All rights reserved.

Spawning Behaviour and the Softmouth Trout Dilemma

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Esteve Manu

2014-07-01

Full Text Available Morphological, ecological and molecular data sets do not completely agree on the phylogenetic placement of the softmouth trout, Salmo (Salmothymus obtusirostris (Heckel. Molecules posit that softmouths are closely related to brown trout, Salmo trutta L. while some morphological, ecological and life history traits place them in the most basal position of the Salmoninae subfamily between grayling (Thymallus and lenok (Brachymystax. Here we add an additional source of data, behavioural characters based on the first reported observations of softmouth spawning. During spawning softmouth females present three important behaviours not found in the other Salmo members: they continually abandon their nests, rarely staying on them for periods over nine minutes; they expel different batches of eggs at the same nest at intervals of several minutes; and they do not cover their eggs immediately after spawning. These three behaviours are intriguing for two reasons: 1 they are possible homologous to behaviours found in grayling females; 2 when coupled to the nest digging behaviour-widespread in all the salmonines, including softmouths, they seem to be mal-adaptive.

Bacteriophages safely reduce Salmonella contamination in pet food and raw pet food ingredients.

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Soffer, Nitzan; Abuladze, Tamar; Woolston, Joelle; Li, Manrong; Hanna, Leigh Farris; Heyse, Serena; Charbonneau, Duane; Sulakvelidze, Alexander

2016-01-01

Contamination of pet food with Salmonella is a serious public health concern, and several disease outbreaks have recently occurred due to human exposure to Salmonella tainted pet food. The problem is especially challenging for raw pet foods (which include raw meats, seafood, fruits, and vegetables). These foods are becoming increasingly popular because of their nutritional qualities, but they are also more difficult to maintain Salmonella -free because they lack heat-treatment. Among various methods examined to improve the safety of pet foods (including raw pet food), one intriguing approach is to use bacteriophages to specifically kill Salmonella serotypes. At least 2 phage preparations (SalmoFresh® and Salmonelex™) targeting Salmonella are already FDA cleared for commercial applications to improve the safety of human foods. However, similar preparations are not yet available for pet food applications. Here, we report the results of evaluating one such preparation (SalmoLyse®) in reducing Salmonella levels in various raw pet food ingredients (chicken, tuna, turkey, cantaloupe, and lettuce). Application of SalmoLyse® in low (ca. 2-4×10 6 PFU/g) and standard (ca. 9×10 6 PFU/g) concentrations significantly ( P contamination in all raw foods examined compared to control treatments. When SalmoLyse®-treated (ca. 2×10 7 PFU/g) dry pet food was fed to cats and dogs, it did not trigger any deleterious side effects in the pets. Our data suggest that the bacteriophage cocktail lytic for Salmonella can significantly and safely reduce Salmonella contamination in various raw pet food ingredients.

Total and cytosolic concentrations of twenty metals/metalloids in the liver of brown trout Salmo trutta (Linnaeus, 1758) from the karstic Croatian river Krka.

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Dragun, Zrinka; Filipović Marijić, Vlatka; Krasnići, Nesrete; Ivanković, Dušica; Valić, Damir; Žunić, Jakov; Kapetanović, Damir; Smrzlić, Irena Vardić; Redžović, Zuzana; Grgić, Ivana; Erk, Marijana

2018-01-01

Total and cytosolic concentrations of twenty metals/metalloids in the liver of brown trout Salmo trutta (Linnaeus, 1758) were studied in the period from April 2015 to May 2016 at two sampling sites on Croatian river Krka, to establish if river water contamination with metals/metalloids downstream of Knin town has influenced metal bioaccumulation in S. trutta liver. Differences were observed between two sites, with higher concentrations of several elements (Ag, As, Ca, Co, Na, Se, Sr, V) found downstream of Knin town, whereas few others (Cd, Cs, Mo, Tl) were, unexpectedly, increased at the Krka River spring. However, total metal/metalloid concentrations in the liver of S. trutta from both sites of the Krka River were still mainly below previously reported levels for pristine freshwaters worldwide. The analysis of seasonal changes of metal/metalloid concentrations in S. trutta liver and their association with fish sex and size mostly indicated their independence of fish physiology, making them good indicators of water contamination and exposure level. Metal/metalloid concentrations in the metabolically available hepatic cytosolic fractions reported in this study are the first data of that kind for S. trutta liver, and the majority of analyzed elements were present in the cytosol in the quantity higher than 50% of their total concentrations, thus indicating their possible availability for toxic effects. However, the special attention should be directed to As, Cd, Cs, and Tl, which under the conditions of increased exposure tended to accumulate more within the cytosol. Although metal/metalloid concentrations in S. trutta liver were still rather low, monitoring of the Krka River water quality and of the health status of its biota is essential due to a trend of higher metal/metalloid bioaccumulation downstream of Knin town, especially taking into consideration the proximity of National Park Krka and the need for its conservation. Copyright © 2017 Elsevier Inc. All

An oil containing EPA and DHA from transgenic Camelina sativa to replace marine fish oil in feeds for Atlantic salmon (Salmo salar L.: Effects on intestinal transcriptome, histology, tissue fatty acid profiles and plasma biochemistry.

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Mónica B Betancor

Full Text Available New de novo sources of omega 3 (n-3 long chain polyunsaturated fatty acids (LC-PUFA are required as alternatives to fish oil in aquafeeds in order to maintain adequate levels of the beneficial fatty acids, eicosapentaenoic and docosahexaenoic (EPA and DHA, respectively. The present study investigated the use of an EPA+DHA oil derived from transgenic Camelina sativa in Atlantic salmon (Salmo salar feeds containing low levels of fishmeal (35% and fish oil (10%, reflecting current commercial formulations, to determine the impacts on tissue fatty acid profile, intestinal transcriptome, and health of farmed salmon. Post-smolt Atlantic salmon were fed for 12-weeks with one of three experimental diets containing either a blend of fish oil/rapeseed oil (FO, wild-type camelina oil (WCO or transgenic camelina oil (DCO as added lipid source. The DCO diet did not affect any of the fish performance or health parameters studied. Analyses of the mid and hindgut transcriptomes showed only mild effects on metabolism. Flesh of fish fed the DCO diet accumulated almost double the amount of n-3 LC-PUFA than fish fed the FO or WCO diets, indicating that these oils from transgenic oilseeds offer the opportunity to increase the n-3 LC-PUFA in farmed fish to levels comparable to those found a decade ago.

Recovery of young brown trout (Salmo trutta) in acidified streams: What are the critical values for acid-neutralizing capacity?

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Hesthagen, T.; Fiske, P.; Saksgård, R.

2016-12-01

The recovery of young allopatric brown trout (Salmo trutta) grouped into YoY (age 0+) and older parr (age ≥1+) fish, was studied in acid-sensitive streams in a Norwegian watershed during a 24-year-period (1987-2010). Their abundance was assessed by electrofishing. Most sites typically had 5.0-5.5 in pH, 0.4-0.7 mg L-1 Ca, 10-20 μg L-1 inorganic toxic aluminum (Ali) and acid-neutralizing capacity adjusted for organic acids (ANCOAA) of - 15 to +25 μeq L-1. Densities of both YoY and older parr increased significantly during the study period. Water quality also improved in recent years with respect to pH (5.8-6.0), Ali (5-15 μg L-1) and ANCOAA (10-20 μeq L-1). However, some negative trends in both fish density and water chemistry were found during both the first (1987-1993) and last years (2004-2008) of the study. Initially, YoY densities remained at about 16-20 specimens 100 m-2 (1987-1990), declined to 10-15 specimens 100 m-2 in the early/mid 1990s, and rosed to 30-50 specimens 100 m-2 in recent years (1997-2010). Their densities correlated significantly with ANCOAA, and at least three stages in the recovery process were recognised: (i) Low density with 10-20 specimens 100 m-2 at -18 to -5 μeq L-1, (ii) medium and unstable density with 20-30 specimens 100 m-2 at -5 to 10 μeq L-1, and (iii) increasing density to 40-50 specimens 100 m-2 at 10-25 μeq L-1. The decline in brown trout density in the early-mid 1990s coincided with high sea salt depositions, which caused increased acidification. Component 1 in a PCA explained 51% of the variation in fish densities, including conductivity, Mg, Ca, Na, alkalinity and TOC. Component 2 explained an additional 31% of the variation, including pH, Ali and ANCOAA. Multiple regression analysis coefficients showed that the two components explained 41% of the variance in total fish density. Young brown trout suffered a high mortality during the initial phase of the study in spite of relative low levels of Ali. This is

A description and assessment of the Atlantic salmon (salmo salar) fall pre-smolt migration in relation to the Tobique narrows hydroelectric facility, Tobique River, New Brunswick using radio telemetry

International Nuclear Information System (INIS)

Jones, R.A.; Flanagan, J.J.

2007-01-01

Atlantic salmon (salmo salar) smolts typically migrate to the ocean in the spring following 2 to 4 years in freshwater. However, in some rivers, migration can also begin in the fall for a small component of the population of known as pre-smolts. These fish do not complete their migration to the ocean in the fall, but rather remain in freshwater, closer to the marine environment, until the following spring when they complete their migration. This report presented the results of a collaborative research project between New Brunswick Power Commission, Fisheries and Oceans Canada, Atlantic Salmon Federation, University of New Brunswick and the Tobique Salmon Protective Association that utilized radio telemetry to study the spatial and temporal movements of fall migrating, wild Atlantic salmon pre-smolts in the upstream and downstream vicinities of the Tobique Narrows Dam. In order to provide an estimation of the fall pre-smolt population migrating from the Tobique River, rotary screw traps were used along with a mark recapture method. It was hoped that the results from this radio tagging experiment would facilitate the establishment of an effective downstream fish passage and/or collection strategies for juvenile salmon. The report described the study area; Tobique Narrows Dam; catches and estimates; radio tagging; fixed radio receivers; and searches. Results were presented for catches and estimates; migration to Arthurette; migration to Tobique Narrows Dam; operating conditions at Tobique Narrows Dam; estimated numbers of pre-smolts up river and down river of the Tobique Narrows Dam; and migration to Beechwood Dam. Recommendations and considerations for future evaluations or research were also presented. 29 refs., 8 tabs., 18 figs., 3 appendices

Exposure of Atlantic salmon parr (Salmo salar) to a combination of resin acids and a water soluble fraction of diesel fuel oil: A model to investigate the chemical causes of pigmented salmon syndrome

International Nuclear Information System (INIS)

Croce, B.; Scottish Environmental Protection Agency, Aberdeen; Stagg, R.M.

1997-01-01

Pigmented salmon syndrome is a pollutant-induced hemolytic anemia and hyperbilirubinemia. As part of an investigation of this condition, S2 Atlantic salmon parr (Salmo salar) were exposed to a diesel fuel oil, water soluble fraction (WSF) in combination with a mixture of three resin acids (isopimaric, dehydroabietic, and abietic acids) in a continuous-flow freshwater system. The total nominal concentrations of resin acids in the exposure tanks were 10, 50, and 100 microg/L; the diesel WSF was generated in situ and provided a mean hydrocarbon concentration of 2.0 ± 0.1 mg/L (n = 12) during the 9-d exposure period. Exposure to the diesel WSF alone depressed liver bilirubin UDP-glucuronosyl transferase (UDPGT) activity and induced phenol UDPGT activity. Exposure to the diesel WSF in the absence or presence of resin acids induced liver cytochrome P4501A and increased the concentrations in the plasma of the enzymes lactate dehydrogenase, alkaline phosphatase, and glutamic oxaloacetic transaminase. The combined exposure to diesel WSF with either 50 or 100 microg/L total resin acid caused significant elevations in the concentrations of bilirubin in the plasma and many of these fish had yellow pigmentation on the ventral surface and around the gill arches. The results demonstrate that exposure to combinations of two groups of contaminants can result in the manifestation of toxic effects not apparent from exposure to either of these chemicals in isolation

Effects of some chelating agents on the uptake and distribution of 203Hg2+ in the brown trout (Salmo trutta): Studies on ethyl- and isopropylxanthate diethyl- and diisopropyldithiophosphate, dimethyl- and diethyldithiocarbamate and pyridinethione

International Nuclear Information System (INIS)

Borg, K.; Gottofrey, J.; Tjaelve, H.

1988-01-01

Brown trout, Salmo trutta, were exposed to water containing 0.1 μg/l 203 Hg 2+ , alone or with potassium ethylxanthate (PEX), sodium isopropylxanthate (SIX), sodium diethyldithiophosphate (SEP), sodium diisopropyldithiophosphate (SIP), sodium dimethyldithiocarbamate (SMC), sodium diethyldithiocarbamate (SEC) or sodium pyridinethione (SPyr), respectively. After 1 week the uptake and distribution of the 203 Hg 2+ in the fish were examined by gamma spectrometry, SIX, SIP, SMC, SEC and SPyr induced 2-3 times higher 203 Hg 2+ concentrations in most tissues in comparison with trout exposed to 203 Hg 2+ only. In the trout exposed to PEX slightly enhanced 203 Hg 2+ levels were found only in some tissues, and after exposure to SEP a few tissues showed decreased 203 Hg 2+ concentrations. Determinations of chloroform/water partition coefficients showed that lipophilic chelates are formed between all the examined substances and the 203 Hg 2+ . However, SIX, SIP, SMC, SEC and SPyr, which induced markedly increased tissue levels of the metal, formed 203 Hg 2+ complexes with higher lipophilicities than SEX and SEP. A facilitated penetration of the lipophilic 203 Hg 2+ complexes over the gill membranes may underly the increment in the tissue levels of the metal, and the relative lipophilicity of the complexes may be of importance for this effect. In some instances, as with SEP, the 203 Hg 2+ chelated in complexes with low lipophilicity may even be less able to acumulate in some tissues than the non-complexed metal. (orig.)

Dose-dependent hepatic transcriptional responses in Atlantic salmon (Salmo salar) exposed to sublethal doses of gamma radiation

Energy Technology Data Exchange (ETDEWEB)

Song, You, E-mail: you.song@niva.no [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, N-0349 Oslo (Norway); Salbu, Brit; Teien, Hans-Christian; Heier, Lene Sørlie [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Rosseland, Bjørn Olav [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Norwegian University of Life Sciences (NMBU), Department of Ecology and Natural Resource Management, P.O. Box 5003, N-1432 Ås (Norway); Tollefsen, Knut Erik [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, N-0349 Oslo (Norway)

2014-11-15

Highlights: • First study on early stress responses in salmon exposed to low-dose gamma radiation. • Dramatic dose-dependent transcriptional responses characterized. • Multiple modes of action proposed for gamma radiation. - Abstract: Due to the production of free radicals, gamma radiation may pose a hazard to living organisms. The high-dose radiation effects have been extensively studied, whereas the ecotoxicity data on low-dose gamma radiation is still limited. The present study was therefore performed using Atlantic salmon (Salmo salar) to characterize effects of low-dose (15, 70 and 280 mGy) gamma radiation after short-term (48 h) exposure. Global transcriptional changes were studied using a combination of high-density oligonucleotide microarrays and quantitative real-time reverse transcription polymerase chain reaction (qPCR). Differentially expressed genes (DEGs; in this article the phrase gene expression is taken as a synonym of gene transcription, although it is acknowledged that gene expression can also be regulated, e.g., at protein stability and translational level) were determined and linked to their biological meanings predicted using both Gene Ontology (GO) and mammalian ortholog-based functional analyses. The plasma glucose level was also measured as a general stress biomarker at the organism level. Results from the microarray analysis revealed a dose-dependent pattern of global transcriptional responses, with 222, 495 and 909 DEGs regulated by 15, 70 and 280 mGy gamma radiation, respectively. Among these DEGs, only 34 were commonly regulated by all radiation doses, whereas the majority of differences were dose-specific. No GO functions were identified at low or medium doses, but repression of DEGs associated with GO functions such as DNA replication, cell cycle regulation and response to reactive oxygen species (ROS) were observed after 280 mGy gamma exposure. Ortholog-based toxicity pathway analysis further showed that 15 mGy radiation

TAILLE À 3 ANS DE LA TRUITE COMMUNE (SALMO TRUTTA L. DANS LES RIVIÈRES DES PYRÉNÉES FRANÇAISES : RELATIONS AVEC LES CARACTÉRISTIQUES MÉSOLOGIQUES ET INFLUENCE DES AMÉNAGEMENTS HYDROÉLECTRIQUES. TOTAL LENGTH OF AGE-3 BROWN TROUT (SALMO TRUTTA L. IN FRENCH PYRENEAN STREAMS : RELATIONSHIPS WITH ENVIRONMENTAL FACTORS AND INFLUENCE OF HYDROELECTRIC FACILITIES.

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LAGARRIGUE T.

2008-05-01

Full Text Available La croissance de populations de truite commune (Salmo trutta L. a été étudiée sur 84 cours d'eau répartis sur l'ensemble de la chaîne des Pyrénées. Pour cela, des échantillons d'écailles ont été récoltés dans 215 sites situés à des altitudes comprises entre 185 et 2000 m, pour des largeurs variant de 1,2 à 60 m. La croissance des individus a été déterminée par scalimétrie. La longueur totale moyenne atteinte par les individus à l'âge de 3 ans a été retenue comme variable biologique. La taille moyenne à 3 ans des individus est fortement structurée par l'altitude, ce gradient altitudinal représentant en grande partie un gradient thermique. Elle est corrélée négativement avec l'altitude et la densité totale en truites communes et positivement avec la largeur du cours d'eau et la conductivité estivale. La nature du débit joue également un rôle important sur la croissance puisqu'à altitude et à température moyenne estivale équivalentes, la taille moyenne à 3 ans est significativement plus faible en site soumis à un débit réservé qu'en site à débit naturel. Selon la nature du débit, deux modèles prédictifs de la taille moyenne à 3 ans (T3 en fonction de l'altitude (ALT et de la largeur du cours d'eau (L ont été établis par régression multiple pas à pas : - sites à débit naturel : Log (T3 = 2.457 - 0.007 x sgrt ALT + 0.066 x Log (L 65.5 % (p The growth of brown trout (Salmo trutta L. populations has been studied on 84 streams distributed over the whole range of the Pyrenees. Samples of scales were collected in 215 sites located at altitudes ranging between 185 and 2000 m, for width varying from 1,2 to 60 m. The growth of individuals was determined by scale reading. The mean total length of age-3 trout was selected as the biological variable. The mean total length of age-3 trout was strongly structured by altitude, this altitudinal gradient mainly representing a thermal gradient. It is

Phylogeography and taxonomic status of trout and salmon from the Ponto-Caspian drainages, with inferences on European Brown Trout evolution and taxonomy.

Science.gov (United States)

Ninua, Levan; Tarkhnishvili, David; Gvazava, Elguja

2018-03-01

Current taxonomy of western Eurasian trout leaves a number of questions open; it is not clear to what extent some species are distinct genetically and morphologically. The purpose of this paper was to explore phylogeography and species boundaries in freshwater and anadromous trout from the drainages of the Black and the Caspian Seas (Ponto-Caspian). We studied morphology and mitochondrial phylogeny, combining samples from the western Caucasus within the potential range of five nominal species of trout that are thought to inhabit this region, and using the sequences available from GenBank. Our results suggest that the genetic diversity of trout in the Ponto-Caspian region is best explained with the fragmentation of catchments. (1) All trout species from Ponto-Caspian belong to the same mitochondrial clade, separated from the other trout since the Pleistocene; (2) the southeastern Black Sea area is the most likely place of diversification of this clade, which is closely related to the clades from Anatolia; (3) The species from the Black Sea and the Caspian Sea drainages are monophyletic; (4) except for the basal lineage of the Ponto-Caspian clade, Salmo rizeensis , all the lineages produce anadromous forms; (5) genetic diversification within the Ponto-Caspian clade is related to Pleistocene glacial waves; (6) the described morphological differences between the species are not fully diagnostic, and some earlier described differences depend on body size; the differences between freshwater and marine forms exceed those between the different lineages. We suggest a conservative taxonomic approach, using the names S. rizeensis and Salmo labrax for trout from the Black Sea basin and Salmo caspius and Salmo ciscaucasicus for the fish from the Caspian basin.

Immunomodulatory Effects of Dietary Seaweeds in LPS Challenged Atlantic Salmon Salmo salar as Determined by Deep RNA Sequencing of the Head Kidney Transcriptome

Science.gov (United States)

Palstra, Arjan P.; Kals, Jeroen; Blanco Garcia, Ainhoa; Dirks, Ron P.; Poelman, Marnix

2018-01-01

Seaweeds may represent immuno-stimulants that could be used as health-promoting fish feed components. This study was performed to gain insights into the immunomodulatory effects of dietary seaweeds in Atlantic salmon. Specifically tested were 10% inclusion levels of Laminaria digitata (SW1) and a commercial blend of seaweeds (Oceanfeed®) (SW2) against a fishmeal based control diet (FMC). Differences between groups were assessed in growth, feed conversion ratio and blood parameters hematocrit and hemoglobin. After a LPS challenge of fish representing each of the three groups, RNAseq was performed on the head kidney as major immune organ to determine transcriptomic differences in response to the immune activation. Atlantic salmon fed with dietary seaweeds did not show major differences in performance in comparison with fishmeal fed fish. RNAseq resulted in ∼154 million reads which were mapped against a NCBI Salmo salar reference and against a de novo assembled S. salar reference for analyses of expression of immune genes and ontology of immune processes among the 87,600 cDNA contigs. The dietary seaweeds provoked a more efficient immune response which involved more efficient identification of the infection site, and processing and presentation of antigens. More specifically, chemotaxis and the chemokine-mediated signaling were improved and therewith the defense response to Gram-positive bacterium reduced. Specific Laminaria digitata effects included reduction of the interferon-gamma-mediated signaling. Highly upregulated and specific for this diet was the expression of major histocompatibility complex class I-related gene protein. The commercial blend of seaweeds caused more differential expression than Laminaria digitata and improved immune processes such as receptor-mediated endocytosis and cell adhesion, and increased the expression of genes involved in response to lipopolysaccharide and inflammatory response. Particularly, expression of many important immune

Biologia do jundiá Rhamdia quelen (Teleostei, Pimelodidae Biology of Rhamdia quelen (Teleostei, Pemelodidae

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Levy de Carvalho Gomes

2000-03-01

Full Text Available O jundiá, Rhamdia quelen, é encontrado desde o centro da Argentina até o sul do México, e seu cultivo está aumentando no sul do Brasil. Portanto, o objetivo desta revisão é apresentar os dados existentes até o momento sobre a biologia dessa espécie. R. quelen pode atingir 50cm de comprimento e 3kg de peso, possui hábito noturno e habita locais calmos e profundos dos rios. Os alevinos suportam água do mar a 10%o, até 9,0g/l de sal comum e pH na faixa de 4,0 a 8,5, com melhor crescimento das larvas na faixa de pH de 8,0 a 8,5. É uma espécie euritérmica. Esse peixe é omnívoro, com tendência piscívora. A maturidade sexual é atingida no primeiro ano de vida. É uma espécie ovulípara e, na natureza, os cardumes desovam em locais com água limpa, calma e de fundo pedregoso. Não apresenta cuidado parental. Possui dois picos reprodutivos por ano (um no verão e outro na primavera e desova múltipla. A indução da desova apresentou bons resultados com gonadotrofina coriônica humana (HCG ou extrato hipofisário. O desenvolvimento embrionário de R. quelen é rápido e se dá entre 3 a 5 dias. O melhor alimento artificial para larvas de R. quelen é baseado em lecitina de soja, fígado bovino e levedura. Várias bactérias patogênicas e trematódeos digenéticos já foram identificados em R. quelen. Para um melhor aproveitamento dessa espécie na piscicultura, são necessários mais estudos relacionados ao efeito de parâmetros físicoquímicos da água, alimentação artificial e crescimento em cativeiro.The jundiá, Rhamdia quelen, occurs from Southern Mexico to Central Argentina, and the husbandry of this species is spreading in Southern Brazil. Consequently, the aim of this review is to present the available data of the biology of this species. R. quelen can reach 50cm of length and 3kg of weight, presents a nocturnal habit and lives in placid and deep waters of the rivers. Fingerlings support 10‰ seawater, up to 9g/l table salt and 4.0 - 8.5 pH range, with best growth at 8.0 - 8.5 pH range. It is an eurytermal species. This fish is omnivorous, but prefers fish. The sexual maturity is reached in the first year of life, and it is ovuliparous and in the natural environment the schools spawn in clean and calm waters with rocky bottom. There is no parental care. This species shows two reproductive peaks/year (spring and summer and multiple spawning. The induced spawning had good results with human chorionic gonadotrofin (HCG or pituitary extract. The embriological development of R. quelen is fast, and the larval development occurs in three to five days. The best feeding ration to the larvae of R. quelen is based on soybean lecithin, cattle liver and yeast. Several pathogenic bacteria and digenetic trematoda were identified in R. quelen. To improve the use of this species in fish culture, additional studies about physico-chemical parameters of the water, feeding rations and growth in captivity are essential.