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Sample records for acipenser oxyrinchus desotoi

  1. Surgical removal of cataracts due to Diplostomum species in Gulf sturgeon (Acipenser oxyrinchus desotoi).

    PubMed

    Bakal, Robert S; Hickson, Brian H; Gilger, Brian C; Levy, Michael G; Flowers, James R; Khoo, Lester

    2005-09-01

    Twenty 6-yr-old (1995-yr-class) Gulf of Mexico sturgeon (Acipenser oxyrinchus desotoi) were diagnosed as having bilateral cataracts. Histopathologic assessment of the lenses of two of the fish revealed the presence of a diplostomid trematode. Pharmacological treatment of the trematodes may be effective for killing the parasites, but the damage to the lenses and resulting cataracts are nonreversible. Because these animals were to be used in a subsequent study as sentinels in the natural environment, it was necessary to return the animals' vision to as close to normal as possible. Electroretinograms were performed on each fish's eyes to ensure that retinal function was present. Cataracts then were surgically removed by phacoemulsification and aspiration. The animals tolerated the surgical procedures well. This report is the first known report of surgical correction of cataracts in sturgeon species. It also is the first known attempt to correct vision problems in fish being returned to the wild.

  2. Evidence of autumn spawning in Suwannee River Gulf sturgeon, Acipenser oxyrinchus desotoi (Vladykov, 1955)

    USGS Publications Warehouse

    Randall, M.T.; Sulak, K.J.

    2012-01-01

    Evidence of autumn spawning of Gulf sturgeon Acipenser oxyrinchus desotoi in the Suwannee River, Florida, was compiled from multiple investigations between 1986 and 2008. Gulf sturgeon are known from egg collections to spawn in the springtime months following immigration into rivers. Evidence of autumn spawning includes multiple captures of sturgeon in September through early November that were ripe (late-development ova; motile sperm) or exhibited just-spawned characteristics, telemetry of fish that made >175 river kilometer upstream excursions to the spawning grounds in September–October, and the capture of a 9.3 cm TL age-0 Gulf sturgeon on 29 November 2000 (which would have been spawned in late September 2000). Analysis of age-at-length data indicates that ca. 20% of the Suwannee River Gulf sturgeon population may be attributable to autumn spawning. However, with the very low sampling effort expended, eggs or early life stages have not yet been captured in the autumn, which would be the conclusive proof of autumn spawning. More sampling, and sampling at previously unknown sites frequented by acoustic telemetry fish, would be required to find eggs.

  3. Endoscopic sex determination and gonadal manipulation in Gulf of Mexico sturgeon (Acipenser oxyrinchus desotoi).

    PubMed

    Hernandez-Divers, Stephen J; Bakal, Robert S; Hickson, Brian H; Rawlings, Clarence A; Wilson, Heather G; Radlinsky, MaryAnn; Hernandez-Divers, Sonia M; Dover, Samuel R

    2004-12-01

    Seventeen Gulf of Mexico sturgeons (Acipenser oxyrinchus desotoi) underwent endoscopic sex determination, gonadal biopsy, and various reproductive surgeries as part of a conservation development plan. The fish were anesthetized with tricaine methanesulfonate (MS-222) buffered with sodium bicarbonate and maintained on a recirculating water anesthesia circuit. A 6-mm Ternamian EndoTip Cannula, placed through the ventral midline, midway between pectoral and pelvic fins, permitted the introduction of a 5-mm telescope. Swim bladder aspiration and CO2 insufflation of the coelomic cavity provided excellent observation. Second and third cannulae were placed under direct visual control, lateral and cranial or caudal to the telescope cannula. Sex determination was successfully performed in all fish; however, five of 17 sturgeons (29%) required endoscopic gonadal biopsy to confirm sex. Bilateral ovariectomy or orchidectomy was successfully performed in three males and four females. Unilateral ovariectomy and bilateral ligation of the müllerian ducts using an extracorporeal suturing technique was accomplished in an additional three females. No apparent morbidity was associated with the anesthesia or endoscopic surgery in any fish. The ability to safely perform minimally invasive reproductive surgery in fish may have important management and conservation benefits.

  4. Quantitative assessment of benthic food resources for juvenile Gulf sturgeon, Acipenser oxyrinchus desotoi in the Suwannee River estuary, Florida, USA

    USGS Publications Warehouse

    Brooks, R.A.; Sulak, K.J.

    2005-01-01

    Gulf sturgeon, Acipenser oxyrinchus desotoi, forage extensively in the Suwannee River estuary following emigration out of the Suwannee River, Florida. While in the estuary, juvenile Gulf sturgeon primarily feed on benthic infauna. In June-July 2002 and February-April 2003, random sites within the estuary were sampled for benthic macrofauna (2002 n = 156; 2003 n = 103). A mean abundance of 2,562 ind m-2 (SE ?? 204) was found in the summer, with significantly reduced macrofaunal abundance in the winter (mean density of 1,044 ind m-2, SE ?? 117). Benthic biomass was significantly higher in the summer with an average summer sample dry weight of 5.92 g m-2 (SE ?? 0.82) compared to 3.91 g m-2 (SE ?? 0.67) in the winter. Amphipods and polychaetes were the dominant taxa collected during both sampling periods. Three different estimates of food availability were examined taking into account principal food item information and biomass estimates. All three estimates provided a slightly different view of potential resources but were consistent in indicating that food resource values for juvenile Gulf sturgeon are spatially heterogeneous within the Suwannee River estuary. ?? 2005 Estuarine Research Federation.

  5. Ontogenetic behavior and migration of Gulf of Mexico sturgeon, Acipenser oxyrinchus desotoi, with notes on body color and development

    USGS Publications Warehouse

    Kynard, B.; Parker, E.

    2004-01-01

    We observed Suwannee River Gulf sturgeon, Acipenser oxyrinchus desotoi, in the laboratory and found free embryos (first interval after hatching) hid under rocks and did not migrate. Thus, wild embryos should be at the spawning area. Larvae (first interval feeding exogenously) initiated a slow downstream migration, and some juveniles (interval with adult features) continued to migrate slowly for at least 5 months, e.g., a 1-step long larva-juvenile migration. No other population of sturgeon yet studied has this migration style. A conceptual model using this result suggests wild year-0 sturgeon have a variable downstream migration style with short-duration (short distance) migrants and long-duration (long distance) migrants. This migration style should widely disperse wild fish. The model is supported by field studies that found year-0 juveniles are widely dispersed in fresh water to river km 10. Thus, laboratory and field data agree that the entire freshwater reach of river downstream of spawning is nursery habitat. Foraging position of larvae and early juveniles was mostly on the bottom, but fish also spent hours holding position in the water column, an unusual feeding location for sturgeons. The holding position of fish above the bottom suggests benthic forage in the river is scarce and fish have evolved drift feeding. The unusual migration and foraging styles may be adaptations to rear in a river at the southern limit of the species range with poor rearing habitat (low abundance of benthic forage and high summer water temperatures). Suwannee River Gulf sturgeon and Hudson River Atlantic sturgeon, A. o. oxyrinchus, are similar for initiation of migration, early habitat preference, and diel migration. The two subspecies differ greatly for migration and foraging styles, which is likely related to major differences in the quality of rearing habitat. The differences between Atlantic sturgeon populations show the need for geographical studies to represent the behavior

  6. Status of scientific knowledge, recovery progress, and future research directions for the Gulf Sturgeon, Acipenser oxyrinchus desotoi Vladykov, 1955

    USGS Publications Warehouse

    Sulak, Kenneth J.; Parauka, F; Slack, W. Todd; Ruth, T; Randall, Michael; Luke, K; Mette, M. F; Price, M. E

    2016-01-01

    The Gulf Sturgeon, Acipenser oxyrinchus desotoi, is an anadromous species of Acipenseridae and native to North America. It currently inhabits and spawns in the upper reaches of seven natal rivers along the northern coast of the Gulf of Mexico from the Suwannee River, Florida, to the Pearl River, Louisiana, during spring to autumn. Next to the Alligator Gar (Atractosteus spatula), the Gulf Sturgeon is currently the largest fish species occurring in U.S. Gulf Coast rivers, attaining a length of 2.35 m and weights exceeding 135 kg, but historically attained a substantially larger size. Historically, the spawning populations existed in additional rivers from which the species has been wholly or nearly extirpated, such as the Mobile and Ochlockonee rivers, and possibly the Rio Grande River. Most Gulf Sturgeon populations were decimated by unrestricted commercial fishing between 1895–1910. Subsequently most populations remained unrecovered or extirpated due to continued harvest until the 1970s–1980s, and the construction of dams blocking access to ancestral upriver spawning grounds. Late 20th Century harvest bans and net bans enacted by the several Gulf Coast states have stabilized several populations and enabled the Suwannee River population to rebound substantially and naturally. Hatchery supplementation has not been necessary in this regard to date. Sturgeon are resilient and adaptable fishes with a geological history of 150 million years. Research undertaken since the 1970s has addressed many aspects of Gulf Sturgeon life history, reproduction, migration, population biology, habitat requirements, and other aspects of species biology. However, many knowledge gaps remain, prominently including the life history of early developmental stages in the first year of life. Natural population recovery is evident for the Suwannee River population, but seems promising as well for at least four other populations. The Pascagoula and Pearl River populations face a challenging

  7. Survival of hatchery Gulf sturgeon (Acipenser oxyrinchus desotoi Mitchill, 1815) in the Suwannee River, Florida: a 19-year evaluation

    USGS Publications Warehouse

    Sulak, Kenneth J.; Randall, Michael; Clugston, J.P.

    2014-01-01

    An experimental release of 1192 hatchery-reared, individually PIT tagged, 220 days old (296–337 mm TL) Gulf sturgeon, Acipenser oxyrinchus desotoi, was undertaken in 1992 in the Suwannee River, Florida. The original objectives of the 1992 release experiment were to: (1) evaluate survival rate of cultured Gulf sturgeon in the wild vs survival rate of their wild 1992 cohort counterparts, (2) determine the differential effect of release site within the river upon long-term survival, and (3) evaluate comparative growth rates of recaptured hatchery vs captured wild 1992 cohort Gulf sturgeon. The present investigation addressed those original objectives, plus an additional fourth objective: (4) evaluation of hatchery fish recapture rate change over the 19-year experiment. The primary objective was to determine efficacy of potential conservation aquaculture for this species in terms of long-term survival in the wild. Follow-up 1993–2011 gill net sampling in freshwater reaches (rkm 4–237) and the estuarine river mouth (rkm −6 to 4) yielded recaptures representing 13.0% of the total released. Mean annual hatchery fish mortality (including emigration) rate estimated for the 19-year period (1993–2011) was more than twice that for same cohort wild fish. Mark-recapture survival probability (phi) for hatchery fish, 1993–2011, was substantially lower (0.733) than for their wild counterparts (0.888). Mean annual hatchery fish recapture rate, as a percentage of all 1992 cohort fish recaptures, declined significantly after age-7, coinciding with age of onset of migration into the open Gulf of Mexico. Hypothesized causal factors may be differentially lower fitness in the marine habitat or permanent outmigration due to natal river imprinting failure. Hatchery fish recapture rates varied significantly for fish from the ten release sites, being highest near the river mouth, and lowest for the furthest upriver sites in the Suwannee River and its Santa Fe River tributary

  8. Feeding habitats of the Gulf sturgeon, Acipenser oxyrinchus desotoi, in the Suwannee and Yellow rivers, Florida, as identified by multiple stable isotope analyses

    USGS Publications Warehouse

    Sulak, Kenneth J.; Berg, James J.; Randall, Michael

    2012-01-01

    Stable 13C, 15N, and 34S isotopes were analyzed to define the feeding habitats of Acipenser oxyrinchus desotoi in the Suwannee and Yellow River populations. For the majority (93.9%) of Suwannee subadults and adults, 13C and 34S signatures indicate use of nearshore marine waters as primary winter feeding habitat, probably due to the limiting size of the Suwannee Sound estuary. In the Yellow River population, 13C isotope signatures indicate that adults remain primarily within Pensacola Bay estuary to feed in winter, rather than emigrating to the open Gulf of Mexico. A minor Suwannee River subset (6% of samples), comprised of juveniles and subadults, displayed 13C signatures indicating continued feeding in freshwater during the spring immigration and fall emigration periods. This cannot be interpreted as incidental feeding since it resulted in a 20.5% turnover in tissue δ13C signatures over a 1–3 month period. Cessation of feeding in the general population does not coincide with high river water temperatures. The hypothesis of reduced feeding in freshwater due to localized prey depletion as a result of spatial activity restriction is not supported by the present study. Instead, Suwannee River A. o. desotoi appear to follow two trophic alternatives; 1) complete cessation of feeding immediately upon immigration in spring, continuing through emigration 8–9 months later (the predominant alternative); 2) continued intensive feeding for 1–3 months following immigration, switching to freshwater prey, selected primarily from high trophic levels (i.e., large prey). Stable –34S data verifies that recently immigrated, fully-anadromous A. o. desotoi adults had fed in nearshore marine waters, not offshore waters.

  9. Stock structure and homing fidelity in Gulf of Mexico sturgeon (Acipenser oxyrinchus desotoi) based on restriction fragment length polymorphism and sequence analyses of mitochondrial DNA.

    PubMed

    Stabile, J; Waldman, J R; Parauka, F; Wirgin, I

    1996-10-01

    Efforts have been proposed worldwide to restore sturgeon populations through the use of hatcheries to supplement natural reproduction and to reintroduce sturgeon where they have become extinct. We examined the population structure and inferred the extent of homing in the anadromous Gulf of Mexico (Gulf) sturgeon (Acipenser oxyrinchus desotoi). Restriction fragment length polymorphism and control region sequence analyses of mitochondrial DNA (mtDNA) were used to identify haplotypes of Gulf sturgeon specimens obtained from eight drainages spanning the subspecies' entire distribution from Louisiana to Florida. Significant differences in haplotype frequencies indicated substantial geographic structuring of populations. A minimum of four regional or river-specific populations were identified (from west to east): (1) Pearl River, LA and Pascagoula River, MS, (2) Escambia and Yellow rivers, FI, (3) Choctawbatchee River, FL and (4) Apalachicola Ochlockonee, and Suwannee rivers, FL. Estimates of maternally mediated gene flow between any pair of the four regional or river-specific stocks ranged between 0.15 to 1.2. Tandem repeats in the mtDNA control region of Gulf sturgeon were not perfectly conserved. This result, together with an absence of heteroplasmy and length variation in Gulf sturgeon mtDNA, indicates that the molecular mechanisms of mtDNA control region sequence evolution differ among acipenserids.

  10. Stock Structure and Homing Fidelity in Gulf of Mexico Sturgeon (Acipenser Oxyrinchus Desotoi) Based on Restriction Fragment Length Polymorphism and Sequence Analyses of Mitochondrial DNA

    PubMed Central

    Stabile, J.; Waldman, J. R.; Parauka, F.; Wirgin, I.

    1996-01-01

    Efforts have been proposed worldwide to restore sturgeon populations through the use of hatcheries to supplement natural reproduction and to reintroduce sturgeon where they have become extinct. We examined the population structure and inferred the extent of homing in the anadromous Gulf of Mexico (Gulf) sturgeon (Acipenser oxyrinchus desotoi). Restriction fragment length polymorphism and control region sequence analyses of mitochondrial DNA (mtDNA) were used to identify haplotypes of Gulf sturgeon specimens obtained from eight drainages spanning the subspecies' entire distribution from Louisiana to Florida. Significant differences in haplotype frequencies indicated substantial geographic structuring of populations. A minimum of four regional or river-specific populations were identified (from west to east): (1) Pearl River, LA and Pascagoula River, MS, (2) Escambia and Yellow rivers, FL, (3) Choctawhatchee River, FL, and (4) Apalachicola, Ochlockonee, and Suwannee rivers, FL. Estimates of maternally mediated gene flow between any pair of the four regional or river-specific stocks ranged between 0.15 to 1.2. Tandem repeats in the mtDNA control region of Gulf sturgeon were not perfectly conserved. This result, together with an absence of heteroplasmy and length variation in Gulf sturgeon mtDNA, indicates that the molecular mechanisms of mtDNA control region sequence evolution differ among acipenserids. PMID:8889537

  11. Atlantic sturgeons (Acipenser sturio, Acipenser oxyrinchus): American females successful in Europe

    NASA Astrophysics Data System (ADS)

    Tiedemann, Ralph; Moll, Katja; Paulus, Kirsten B.; Scheer, Michael; Williot, Patrick; Bartel, Ryszard; Gessner, Jörn; Kirschbaum, Frank

    2007-03-01

    Recent molecular data on the maternally inherited mitochondrial (mt) DNA have challenged the traditional view that the now extinct Baltic sturgeon population belonged to the European sturgeon Acipenser sturio. Instead, there is evidence that American sea sturgeon Acipenser oxyrinchus historically immigrated into the Baltic Sea. In this study, we test the hypothesis that A. oxyrinchus introgressed into, rather than replaced, the A. sturio population in the Baltic. We established four single nucleotide polymorphisms (SNPs) in the nuclear MHC II antigen gene with a species-specific SNP pattern. Using an ancient DNA approach and two independent lines of molecular evidence (sequencing of allele-specific clones, SNaPshot), we detected both A. sturio and A. oxyrinchus alleles in the available museum material of the now extinct Baltic sturgeon population. The hybrid nature of the Baltic population was further confirmed by very high levels of heterozygosity. It had been previously postulated that the immigration of the cold-adapted A. oxyrinchus into the Baltic occurred during the Medieval Little Ice Age, when temperature likely dropped below the degree inducing spawning in A. sturio. Under this scenario, our new findings suggest that the genetic mosaic pattern in the Baltic sturgeon population (oxyrinchus mtDNA, sturio and oxyrinchus MHC alleles) is possibly caused by sex-biased introgression where spawning was largely restricted to immigrating American females, while fertilization was predominantly achieved by abundant local European males. The hybrid nature of the former Baltic sturgeon population should be taken into account in the current reintroduction measures.

  12. Population Origin of Atlantic Sturgeon Acipenser oxyrinchus oxyrinchus Bycaught in U.S. Atlantic Coast Fisheries

    PubMed Central

    Wirgin, I.; Maceda, L.; Grunwald, C.; King, T.L.

    2015-01-01

    Microsatellite DNA and mitochondrial DNA control region sequence analyses were used to determine the population and Distinct Population Segment (DPS) origin of 173 Atlantic sturgeon Acipenser oxyrinchus oxyrinchus encountered from the Gulf of Maine to Cape Hatteras, North Carolina in NOAA's Northeast Fisheries Observer Program. It was found that the Hudson River was by far the greatest contributor to this coastal bycatch, with 42.2-46.3% of specimens originating there. Generally, specimens respected the geographic province of the river in which they were spawned, but some specimens, particularly those originating in the South Atlantic DPS, moved great distances. Genetic mixed stock analyses provides an accurate approach to determine the DPS and population origin of Atlantic sturgeon bycaught in coastal waters but most informative management requires that these results be partitioned by locale, season, target fishery, and gear type. PMID:25727098

  13. Effect of chloride on nitrite-induced methaemoglobinemia in Atlantic sturgeon, Acipenser oxyrinchus oxyrinchus (Mitchill).

    PubMed

    Matsche, M A; Markin, E; Donaldson, E; Hengst, A; Lazur, A

    2012-12-01

    We evaluated the effects of chloride concentration on the clinical pathology in juvenile Atlantic sturgeon, Acipenser oxyrinchus oxyrinchus (Mitchill), following semi-static exposures to 1 mg L(-1) nitrite for 96 h. In spring water naturally low in chloride (5 mg L(-1)), plasma nitrite concentrated to more than 40× environmental levels resulting in a severe methaemoglobinemia characterized by torpid behaviour, 30-fold increase in methaemoglobin fraction, anaemia, leucopenia and hyperkalaemia. Loss of intracellular water and potassium to extracellular space may have resulted in hyperkalaemia and haemodilution. Fish survived nitrite exposure, but 60% of torpid fish died following capture and tissue sampling. Fish acclimated to 10-fold higher chloride content (55 mg L(-1)) did not concentrate nitrite in the plasma above environmental levels or develop methaemoglobinemia, but did exhibit similar haematology and plasma chemistry changes. Plasma nitrite returned to preexposure levels by 14 days following nitrite exposures, but severity of clinical pathology changes persisted or increased, suggesting that Atlantic sturgeon have reduced capacity to recover from methaemoglobinemia. Fish that survive methaemoglobinemia may be susceptible to mortality from the cumulative effects of intoxication, handling and other stresses for two or more weeks following nitrite remediation. Chloride buffering in aquaculture systems reduces the toxic effects of nitrite accumulation.

  14. Comparison of mitochondrial DNA control region sequence and microsatellite DNA analyses in estimating population structure and gene flow rates in Atlantic sturgeon Acipenser oxyrinchus

    USGS Publications Warehouse

    Wirgin, I.; Waldman, J.; Stabile, J.; Lubinski, B.; King, T.

    2002-01-01

    Atlantic sturgeon Acipenser oxyrinchus is large, long-lived, and anadromous with subspecies distributed along the Atlantic (A. oxyrinchus oxyrinchus) and Gulf of Mexico (A. o. desotoi) coasts of North America. Although it is not certain if extirpation of some population units has occurred, because of anthropogenic influences abundances of all populations are low compared with historical levels. Informed management of A. oxyrinchus demands a detailed knowledge of its population structure, levels of genetic diversity, and likelihood to home to natal rivers. We compared the use of mitochondrial DNA (mtDNA) control region sequence and microsatellite nuclear DNA (nDNA) analyses in identifying the stock structure and homing fidelity of Atlantic and Gulf coast populations of A. oxyrinchus. The approaches were concordant in that they revealed moderate to high levels of genetic diversity and suggested that populations of Atlantic sturgeon are highly structured. At least six genetically distinct management units were detected using the two approaches among the rivers surveyed. Mitochondrial DNA sequences revealed a significant cline in haplotype diversity along the Atlantic coast with monomorphism observed in Canadian populations. High levels of nDNA diversity were also observed among populations along the Atlantic coast, including the two Canadian populations, probably resulting from the more rapid rate of mutational and evolutionary change at microsatellite loci. Estimates of gene flow among populations were similar between both approaches with the exception that because of mtDNA monomorphism in Canadian populations, gene flow estimates between them were unobtainable. Analyses of both genomes provided high resolution and confidence in characterizing the population structure of Atlantic sturgeon. Microsatellite analysis was particularly informative in delineating population structure in rivers that were recently glaciated and may prove diagnostic in rivers that are

  15. Expression Patterns of Atlantic Sturgeon (Acipenser oxyrinchus) During Embryonic Development

    PubMed Central

    Kaitetzidou, Elisavet; Ludwig, Arne; Gessner, Jörn; Sarropoulou, Elena

    2016-01-01

    During teleost ontogeny the larval and embryonic stages are key stages, since failure during this period of tissue differentiation may cause malformations, developmental delays, poor growth, and massive mortalities. Despite the rapid advances in sequencing technologies, the molecular backgrounds of the development of economically important but endangered fish species like the Atlantic sturgeon (Acipenser oxyrinchus) have not yet been thoroughly investigated. The current study examines the differential expression of transcripts involved in embryonic development of the Atlantic sturgeon. Addressing this goal, a reference transcriptome comprising eight stages was generated using an Illumina HiSequation 2500 platform. The constructed de novo assembly counted to 441,092 unfiltered and 179,564 filtered transcripts. Subsequently, the expression profile of four developmental stages ranging from early (gastrula) to late stages of prelarval development [2 d posthatching (dph)] were investigated applying an Illumina MiSeq platform. Differential expression analysis revealed distinct expression patterns among stages, especially between the two early and the two later stages. Transcripts upregulated at the two early stages were mainly enriched in transcripts linked to developmental processes, while transcripts expressed at the last two stages were mainly enriched in transcripts important to muscle contraction. Furthermore, important stage-specific expression has been detected for the hatching stage with transcripts enriched in molecule transport, and for the 2 dph stage with transcripts enriched in visual perception and lipid digestion. Our investigation represents a significant contribution to the understanding of Atlantic sturgeon embryonic development, and transcript characterization along with the differential expression results will significantly contribute to sturgeon research and aquaculture. PMID:27974440

  16. Using circulating reproductive hormones for sex determination of Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) in the Saco River estuary, Maine

    PubMed Central

    Wheeler, Carolyn R.; Novak, Ashleigh J.; Wippelhauser, Gail S.; Sulikowski, James A.

    2016-01-01

    The Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) is a long-lived, anadromous fish species ranging from Labrador, CA to Florida, USA. In the Saco River, located in the Gulf of Maine, this species was not present during a survey study ending in 1982, but was found inhabiting the estuary in 2007. Although the reason for the return of this sturgeon to this river system remains unknown, research on basic life-history information is necessary to facilitate the conservation of this federally protected species. Given the conservation status of the species, the present study used circulating sex steroid hormones to determine the sex of 288 Atlantic sturgeon captured between 2012 and 2014 in the Saco River estuary located in the Gulf of Maine. Overall, the sex was determined for 93% of Atlantic sturgeon sampled. Mean hormone values were similar to other Atlantic sturgeon reproductive studies. The findings indicate the validity of sex steroid hormones as a singular method for sex determination in wild Atlantic sturgeon. Results also indicated a likely 1:1 (male:female) sex ratio in the system, except in 2014 when a 1:3 ratio was observed. It is not believed that the Saco River estuary is used for spawning, as several impassable dams block access to spawning habitat. However, this area might provide crucial foraging for growth and development of juveniles and a habitat for adults forgoing spawning. PMID:27957335

  17. Immunophysiology of Atlantic sturgeon, Acipenser oxyrinchus oxyrinchus (Mitchill), and the relationship to parasitic copepod, Dichelesthium oblongum (Abilgaard) infection.

    PubMed

    Sokolowski, M S; Allam, B A; Dunton, K J; Clark, M A; Kurtz, E B; Fast, M D

    2012-09-01

    The copepod parasite, Dichelesthium oblongum, is known to infect the Atlantic sturgeon, Acipenser oxyrinchus oxyrinchus, within the area near New York city, USA, known as the NY Bight. The gross pathology associated with the juvenile and adult copepod stages along with the parasite's link in causing changes in sturgeon osmoregulatory capabilities has led us to investigate the host immunophysiology in relation to this host-parasite system. All the host variables, which included gill Na(+) -K(+) -ATPase activity, serum alkaline phosphatase (AP) and white blood cell differential counts, were affected in a non-linear manner by the copepod parasite. The parasites increased the host gill Na(+) -K(+) -ATPase activity and serum AP along with the percentage granulocytes while decreasing the percentage lymphocytes. A new method, developed to sample and preserve white blood cells in the field for future flow cytometry analysis, proved adequate. The effects of fish size, location and time of sampling were accounted for by the use of generalized linear models, and their effects on the host variables are discussed.

  18. Using circulating reproductive hormones for sex determination of Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) in the Saco River estuary, Maine.

    PubMed

    Wheeler, Carolyn R; Novak, Ashleigh J; Wippelhauser, Gail S; Sulikowski, James A

    2016-01-01

    The Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) is a long-lived, anadromous fish species ranging from Labrador, CA to Florida, USA. In the Saco River, located in the Gulf of Maine, this species was not present during a survey study ending in 1982, but was found inhabiting the estuary in 2007. Although the reason for the return of this sturgeon to this river system remains unknown, research on basic life-history information is necessary to facilitate the conservation of this federally protected species. Given the conservation status of the species, the present study used circulating sex steroid hormones to determine the sex of 288 Atlantic sturgeon captured between 2012 and 2014 in the Saco River estuary located in the Gulf of Maine. Overall, the sex was determined for 93% of Atlantic sturgeon sampled. Mean hormone values were similar to other Atlantic sturgeon reproductive studies. The findings indicate the validity of sex steroid hormones as a singular method for sex determination in wild Atlantic sturgeon. Results also indicated a likely 1:1 (male:female) sex ratio in the system, except in 2014 when a 1:3 ratio was observed. It is not believed that the Saco River estuary is used for spawning, as several impassable dams block access to spawning habitat. However, this area might provide crucial foraging for growth and development of juveniles and a habitat for adults forgoing spawning.

  19. Current Occurrence of the Atlantic Sturgeon Acipenser oxyrinchus in Northern Spain: A New Prospect for Sturgeon Conservation in Western Europe

    PubMed Central

    Elvira, Benigno

    2015-01-01

    Acipenser oxyrinchus is considered extirpated in Europe, but numerous breeding populations still exist on the Atlantic coast of North America. An adult female A. oxyrinchus, 2500 mm total length and 120 kg wet weight, was accidentally fished on 24 November 2010 near the coast of Gijón, Asturias, Spain. The fish was identified by its morphological pattern as well as by mitochondrial and nuclear DNA analyses. Because the sturgeon was found far away from any known breeding area, it was considered a stray or vagrant specimen. It certainly has a natural origin, but its eventual birthplace could not be determined. Because its current occurrence was unknown in southwestern Europe until now, the species is not cataloged or protected in this area. Therefore, the residual European stocks of A. oxyrinchus ought to be listed as Critically Endangered (CR) according to the IUCN categories. Likewise, it is imperative for southwestern European countries with an historic or recent occurrence of A. oxyrinchus to protect the species through domestic and international legislation. The present sympatric occurrence of A. sturio and A. oxyrinchus raises new challenges about key questions, such as the species selection for restoration program in European countries. Accurate monitoring is mandatory to obtain appropriate information for an assessment of the current occurrence of A. oxyrinchus in southwestern Europe. PMID:26717564

  20. Current Occurrence of the Atlantic Sturgeon Acipenser oxyrinchus in Northern Spain: A New Prospect for Sturgeon Conservation in Western Europe.

    PubMed

    Elvira, Benigno; Leal, Sheila; Doadrio, Ignacio; Almodóvar, Ana

    2015-01-01

    Acipenser oxyrinchus is considered extirpated in Europe, but numerous breeding populations still exist on the Atlantic coast of North America. An adult female A. oxyrinchus, 2500 mm total length and 120 kg wet weight, was accidentally fished on 24 November 2010 near the coast of Gijón, Asturias, Spain. The fish was identified by its morphological pattern as well as by mitochondrial and nuclear DNA analyses. Because the sturgeon was found far away from any known breeding area, it was considered a stray or vagrant specimen. It certainly has a natural origin, but its eventual birthplace could not be determined. Because its current occurrence was unknown in southwestern Europe until now, the species is not cataloged or protected in this area. Therefore, the residual European stocks of A. oxyrinchus ought to be listed as Critically Endangered (CR) according to the IUCN categories. Likewise, it is imperative for southwestern European countries with an historic or recent occurrence of A. oxyrinchus to protect the species through domestic and international legislation. The present sympatric occurrence of A. sturio and A. oxyrinchus raises new challenges about key questions, such as the species selection for restoration program in European countries. Accurate monitoring is mandatory to obtain appropriate information for an assessment of the current occurrence of A. oxyrinchus in southwestern Europe.

  1. A bibliography of all known publications & reports on the Gulf sturgeon, Acipenser oxyrinchus desotoi

    USGS Publications Warehouse

    Price, Melissa; Adler, Jennifer; Littles, Chanda; Randolph, April Norem; Nash, Ursula A.; Gillett, Bethan; Randall, Michael; Sulak, Kenneth J.; Walsh, Stephen J.; Brownell, Prescott

    2013-01-01

    This functional bibliography is meant to be a complete and comprehensive bibliography of all discoverable reports containing information on the Gulf Sturgeon (GS). This bibliography contains all known reports presenting, documenting, summarizing, listing, or interpreting information on the GS through 31 December 2013. Report citations are organized into four sections. Section I includes published scientific journal articles, books, dissertations and theses, published and unpublished technical reports, published harvest prohibitions, and online articles reporting substantive scientific information. Section II includes newspaper, newsletter, magazine, book, agency news releases, and online articles reporting on GS occurrences, mortalities, captures, jumping, boat collisions, aquaculture, historical photographs, and other largely non-scientific or anecdotal issues. Section III consists of books, theses, ecotour-guides, media articles, editorials, and blogs reporting a mix of anecdotal information, historical information, and opinion on GS conservation, habitat issues, exploitation, aquaculture, and human interaction - but presenting very limited or no substantive scientific information. Section IV includes videos, films and audio recordings documenting GS life history and behavior.

  2. Commercial fishing gear modifications to reduce interactions between Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) and the southern flounder (Paralichthys lethostigma) fishery in North Carolina (USA)

    PubMed Central

    Hager, Christian; Diaddorio, Eric; Dickey, R. Jason

    2016-01-01

    Bycatch of protected species in commercial fishing operations is a primary concern to fishery managers because it threatens the conservation, protection, and recovery of fragile species, such as the Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus). One potential solution to reduce the risk associated with commercial fishing operations is to design commercial fishing gear that is more selective in terms of interactions between Atlantic sturgeon and commercial fisheries. Given this conservation and management need, the overarching goal was to reduce Atlantic sturgeon fishery interactions and maintain southern flounder (Paralichthys lethostigma) catch in North Carolina. The specific objectives of this study were to design and evaluate the effectiveness of a modified gillnet. Overall, the results proved that lowering the profile and amount of webbing had a beneficial impact at reducing Atlantic sturgeon incidental encounters and bycatch. The modified gillnet reduced bycatch and Atlantic sturgeon encounters by 39.6% and 60.9%, respectively. Our design entangled 51.6% fewer southern flounder, which corresponded to a 48.9% reduction in total weight; the modified gear entangled slightly larger southern flounder than the control gear. Our findings showed the number of Atlantic sturgeon encounters was positively associated with mean water depth, with more Atlantic sturgeon encountered in deeper (5.1–6.3 m) than shallower waters; 75% were encountered at depths between 4.6 and 6.1 m. Most southern flounder (n = 518, 39.7%) were taken at a water depth between 3.76 and 5.0 m. This observation suggests that southern flounder prefer slightly shallower waters than Atlantic sturgeon. PMID:27547524

  3. Commercial fishing gear modifications to reduce interactions between Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) and the southern flounder (Paralichthys lethostigma) fishery in North Carolina (USA).

    PubMed

    Levesque, Juan C; Hager, Christian; Diaddorio, Eric; Dickey, R Jason

    2016-01-01

    Bycatch of protected species in commercial fishing operations is a primary concern to fishery managers because it threatens the conservation, protection, and recovery of fragile species, such as the Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus). One potential solution to reduce the risk associated with commercial fishing operations is to design commercial fishing gear that is more selective in terms of interactions between Atlantic sturgeon and commercial fisheries. Given this conservation and management need, the overarching goal was to reduce Atlantic sturgeon fishery interactions and maintain southern flounder (Paralichthys lethostigma) catch in North Carolina. The specific objectives of this study were to design and evaluate the effectiveness of a modified gillnet. Overall, the results proved that lowering the profile and amount of webbing had a beneficial impact at reducing Atlantic sturgeon incidental encounters and bycatch. The modified gillnet reduced bycatch and Atlantic sturgeon encounters by 39.6% and 60.9%, respectively. Our design entangled 51.6% fewer southern flounder, which corresponded to a 48.9% reduction in total weight; the modified gear entangled slightly larger southern flounder than the control gear. Our findings showed the number of Atlantic sturgeon encounters was positively associated with mean water depth, with more Atlantic sturgeon encountered in deeper (5.1-6.3 m) than shallower waters; 75% were encountered at depths between 4.6 and 6.1 m. Most southern flounder (n = 518, 39.7%) were taken at a water depth between 3.76 and 5.0 m. This observation suggests that southern flounder prefer slightly shallower waters than Atlantic sturgeon.

  4. The annual marine feeding aggregation of Atlantic sturgeon Acipenser oxyrinchus in the inner Bay of Fundy: population characteristics and movement.

    PubMed

    Dadswell, M J; Wehrell, S A; Spares, A D; Mclean, M F; Beardsall, J W; Logan-Chesney, L M; Nau, G S; Ceapa, C; Redden, A M; Stokesbury, M J W

    2016-10-01

    Atlantic sturgeon Acipenser oxyrinchus aggregate to feed from May to October in Minas Basin (45° N; 64° W), a large, cul-de-sac embayment of the inner Bay of Fundy. The aggregation consists mainly of migrants from the Saint John, NB and Kennebec Rivers, ME (99%). During 2004-2015, 4393 A. oxyrinchus were taken as by-catch by commercial fish trawlers or at intertidal fishing weirs, and 1453 were marked and/or sampled and released. Fork length (LF ) ranged from 458 to 2670 mm, but 72·5% were <1500 mm. Mass (M) ranged from 0·5 to 58·0 kg. The mass-length relationship for fish ≤50 kg was log10 M = 3·32log10 LF - 5·71. Observed growth of unsexed A. oxyrinchus recaptured after 1-8 years indicated fish of 90-179 cm LF grew c. 2-4 cm a year. Ages obtained from pectoral spines were from 4 to 54 years. The Von Bertalanffy growth model predicted K = 0·01 and L∞ = 5209 mm LF . Estimated annual mortality was 9·5-10·9%. Aggregation sizes in 2008 and 2013 were 8804 and 9244 individuals, respectively. Fish exhibited high fidelity for yearly return to Minas Basin and population estimates indicated the total at-sea number utilizing the Basin increased from c. 10 700 in 2010 to c. 37 500 in 2015. Abundance in the Basin was greatest along the north shore in spring and along the south shore in summer, suggesting clockwise movement following the residual current structure. Marked individuals were recaptured in other bays of the inner Bay of Fundy, north to Gaspé, Quebec, and south to New Jersey, U.S.A., with 26 recoveries from the Saint John River, NB, spawning run. Fish marked at other Canadian and U.S. sites were also recovered in Minas Basin. Since all A. oxyrinchus migrate into and out of the Basin annually they will be at risk of mortality if planned tidal power turbines are installed in Minas Passage.

  5. Complete mitochondrial genome sequences of Atlantic sturgeon, Acipenser oxyrinchus oxyrinchus, Gulf sturgeon, A. o. desotoi and European sturgeon A. sturio (Acipenseriformes: Acipenseridae) obtained through next generation sequencing.

    PubMed

    Popović, Danijela; Baca, Mateusz; Panagiotopoulou, Hanna

    2016-07-01

    Complete mitochondrial genome sequences of European sturgeon and two subspecies of the North American, Atlantic and Gulf sturgeons were determined using MiSeq Illumina technology. All three genomes show typical vertebrate organization. They possess 22 tRNA genes, 13 protein-coding genes, 2 rRNA (ribosomal RNA) genes and a non-coding control region. Excluding ND6, all protein-coding genes are on the heavy strand. The whole mitogenome sequences have been deposited in GenBank under accession numbers KP997216-KP997218.

  6. Recent advances in life history of Gulf of Mexico sturgeon, Acipenser oxyrinchus desotoi, in the Suwannee River, Florida, USA: A synopsis

    USGS Publications Warehouse

    Sulak, K.J.; Clugston, J.P.

    1999-01-01

    Gulf sturgeon spawn on portions of three sites in the upper Suwannee River, which may appropriately be described as spawning reefs. The same areas are utilized from year to year. Habitat factors important in spawning site determination include gravel/cobble substrate, the presence of eddy fields, a neutral to slightly alkaline pH, and an empirically observed range in calcium ion content (6-18 mg/L Ca++, corresponding to a conductivity range of 40-110??S). Eggs are deposited contagiously within a small area ( 3 m) when water temperatures drop in mid-December, but final destinations in mid-winter remain unknown. Age-2 through 6 juveniles remain in the river mouth estuary over winter. In late January through early February YOY migrate downriver for the first time, joining larger juveniles to overwinter and feed. Tag and recapture data yield a Suwannee River population of Gulf sturgeon estimated at 7,650 individuals, with an annual turnover rate of 16%. Based on stability in cumulative recapture rates from 1991-1998, population size is stable with an effective balance between recruitment and mortality. However, population structure is dynamic, controlled by the juxtaposition, conjunction, and summation of successive strong and weak year classes. Length/age frequency distributions for 1995 and 1998 populations censuses are very different. The 1995 distribution is bimodal with a dominant mode of 9-14 year old subadults/adults, and a sub-dominant of mode of 2-4 year old juveniles. The 1998 distribution is trimodal, but overwhelmingly dominated by 6-9 year old subadults. Erosion by 1998 of the major subadult/adult mode from the 1995 census illustrates that large adults encounter the same high mortality as smaller fish. Ultimate adult size in the population has remained constant at 2.2 cm TL over 13 years, indicating a maximum life expectancy of 25 years for Suwannee River Gulf sturgeon.

  7. 75 FR 29316 - Marine Mammals; File No. 13599

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-25

    ... sturgeon (Acipenser brevirostrum) and white abalone (Haliotis sorenseni). The permit holder is requesting... oxyrinchus desotoi) sturgeon, totoaba (Totoaba macdonaldi), and black abalone (Haliotis cracherodii)....

  8. Final Environmental Assessment (EA) for the Revitalization of Military Family Housing Keesler AFB, MS

    DTIC Science & Technology

    2006-03-01

    Sturgeon Acipenser oxyrinchus desotoi T Green Sea Turtle Chelonia mydas T Mississippi Redbellied Turtle Pseudemys sp. E Mississippi Diamondback ... Terrapin Malaclemys terrapin pileata C Gulf Salt Marsh Snake Nerodia clarkii clarkii C ***E = Endangered T = Threatened C = Candidate

  9. 77 FR 20840 - Bogue Chitto National Wildlife Refuge, LA and MS; Final Comprehensive Conservation Plan and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-06

    ... (Potamilus inflatus), and gulf sturgeon (Acipenser oxyrinchus desotoi). Access is primarily by boat on the... was unveiled on the Louisiana side of the refuge. This 3/4-mile walking trail offers a unique...

  10. Assessing Impacts of Navigation Dredging on Atlantic Sturgeon (Acipenser oxyrinchus)

    DTIC Science & Technology

    2014-11-01

    acoustic array. Stations are numbered consecutively denoting increasing upstream distance in the main channel. Station 1 = Kings Mill/Hog Island...at distances of 750 m and as far as 1,000 m during periods of calm weather . A minimum detection range of 250 m was determined in very shallow water...or during high hydrodynamic noise events associated with storms. Two types of individually coded acoustic transmitters that operated at 69 kHz were

  11. First documented occurrences of the shortnose sturgeon (Acipenser brevirostrum) in the Saco River, Maine, USA

    USGS Publications Warehouse

    Little, C.E.; Kieffer, M.; Wippelhauser, G.; Zydlewski, G.; Kinnison, M.; Whitefleet-Smith, L. A.; Sulikowski, J.A.

    2013-01-01

    During sampling efforts to study the more abundant Atlantic sturgeon, Acipenser oxyrinchus oxyrinchus, between May of 2009 and November of 2011, four shortnose sturgeon were captured in gill nets near the mouth of the Saco River, Maine. Two of these individuals were tagged with acoustic transmitters to monitor their movement within the Saco River. Additionally, six shortnose sturgeon that had been tagged with acoustic transmitters in the Merrimack River, Massachusetts were detected on the acoustic array deployed within the Saco River and its estuary over this time period. These incidences represent the first verified documentation of shortnose sturgeon within this estuary.

  12. The Relationship Between Acoustic Target Strength and Body Length for Atlantic Sturgeon (Acipenser oxyrinchus oxyrinchus)

    DTIC Science & Technology

    2010-10-01

    sturgeon feeding portray them as opportunistic benthivores, feeding primar- ily on mollusks, polychaete worms, amphipods , isopods, shrimp and small bottom...May-July in Canada (Smith 1985; Bain 1997; Smith and Clugston 1997). Substrate is a key spawning habitat parameter for Atlantic sturgeon, as hard...maturity. Since juveniles are known to congregate at fresh and saltwater interfaces, these areas may serve as juvenile nursery habitat . Important

  13. Changes in age composition and growth characteristics of Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) over 400 years.

    PubMed

    Balazik, Matthew T; Garman, Greg C; Fine, Michael L; Hager, Christian H; McIninch, Stephen P

    2010-10-23

    Populations of sturgeon (Acipenseridae) have experienced global declines, and in some cases extirpation, during the past century. In the current era of climate change and over-harvesting of fishery resources, climate models, based on uncertain boundary conditions, are being used to predict future effects on the Earth's biota. A collection of approximately 400-year-old Atlantic sturgeon spines from a midden in colonial Jamestown, VA, USA, allowed us to compare the age structure and growth rate for a pre-industrial population during a 'mini-ice age' with samples collected from the modern population in the same reach of the James River. Compared with modern fish, the colonial population was characterized by larger and older individuals and exhibited significantly slower growth rates, which were comparable with modern populations at higher latitudes of North America. These results may relate to higher population densities and/or colder water temperatures during colonial times.

  14. Ontogenetic behavior and migration of Atlantic sturgeon, Acipenser oxyrinchus oxyrinchus, and shortnose sturgeon, A. brevirostrum, with notes on social behavior

    USGS Publications Warehouse

    Kynard, B.; Horgan, M.

    2002-01-01

    Ontogenetic behavior of Hudson River Atlantic sturgeon and Connecticut River shortnose sturgeon early life intervals were similar during laboratory observations. After hatching, free embryos were photonegative and sought cover. When embryos developed into larvae, fish left cover, were photopositive, and initiated downstream migration. Free embryos may remain at the spawning site instead of migrating downstream because the risk of predation at spawning sites is low. The two species are sympatric, but not closely related, so the similarities in innate behaviors suggest common adaptations, not phylogenetlc relationship. Atlantic sturgeon migrated downstream for 12 days (peak, first 6 days), shortnose sturgeon migrated for 3 days, and year-0 juveniles of both species did not resume downstream migration. Short or long migrations of larvae may reflect different styles related to the total migratory distance from spawning sites to juvenile rearing areas. Atlantic sturgeon need to move a short distance to reach rearing areas and they had a long 1-step migration of 6-12 days. In contrast, shortnose sturgeon need to move a long distance to reach all rearing areas. This may be accomplished by a 2-step migration, of which the brief migration of larvae is only the first step. Early migrant Atlantic sturgeon were nocturnal, while late migrants were diurnal, and shortnose sturgeon were diurnal. These diel differences may also be adaptations for long (Atlantic sturgeon) or short (shortnose sturgeon) migrations. Cultured shortnose sturgeon, and possibly Atlantic sturgeon, have a dominance hierarchy with large fish dominant when competing for limited foraging space. Social behavior may be more important in the life history of wild sturgeons than is generally recognized.

  15. Quality assessment of wild Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) semen under conditions of short-term storage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Short-term storage trials were conducted with Atlantic sturgeon semen collected from a total of nine wild males during the 2008 and 2009 spawning seasons on the Hudson River. Semen samples were kept refrigerated (4 plus or minus 1 degree C) and stored in different gaseous atmospheres and storage ext...

  16. Distribution and movement of shortnose sturgeon (Acipenser brevirostrum) in the Chesapeake Bay

    USGS Publications Warehouse

    Welsh, S.A.; Mangold, M.F.; Skjeveland, J.E.; Spells, A.J.

    2002-01-01

    During a reward program for Atlantic sturgeon (Acipenser oxyrinchus), 40 federally endangered shortnose sturgeon (Acipenser brevirostrum) were captured and reported by commercial fishers between January 1996 and January 2000 from the Chesapeake Bay. Since this is more than double the number of published records of shortnose sturgeon in the Chesapeake Bay between 1876 and 1995, little information has been available on distributions and movement. We used fishery dependent data collected during the reward program to determine the distribution of shortnose sturgeon in the Chesapeake Bay. Sonically-tagged shortnose sturgeon in the Chesapeake Bay and Delaware River were tracked to determine if individuals swim through the Chesapeake and Delaware Canal. Shortnose sturgeon were primarily distributed within the upper Chesapeake Bay. The movements of one individual, tagged within the Chesapeake Bay and later relocated in the canal and Delaware River, indicated that individuals traverse the Chesapeake and Delaware Canal.

  17. Oceanic Distribution, Behaviour, and a Winter Aggregation Area of Adult Atlantic Sturgeon, Acipenser oxyrinchus oxyrinchus, in the Bay of Fundy, Canada

    PubMed Central

    Taylor, Andrew Douglas; Ohashi, Kyoko; Sheng, Jinyu; Litvak, Matthew Kenneth

    2016-01-01

    Seasonal distribution of adult Atlantic sturgeon was examined using pop-up satellite archival tags (PSATs) and ultrasonic transmitters deployed in the Saint John River, New Brunswick, Canada. Seven MK10 PSATs programmed for release in June 2012 and seven MiniPAT PSATs programmed for release in February and April 2013 were deployed in August 2011 and 2012, respectively. Eleven of 14 PSATs surfaced and transmitted depth and temperature data archived for the duration of their deployment (121–302 days). Among these eleven PSATs, five were recovered and 15-sec archival data was downloaded. Following exit from the Saint John River in the fall, tagged fish occupied a mean monthly depth of 76.3–81.6 m at temperatures as low as 4.9˚C throughout the winter before returning to shallower areas in the spring. The majority of ultrasonic detections occurred in the Bay of Fundy, but fish were detected as far as Riviere Saint-Jean, Quebec, approximately 1500 km from the Bay of Fundy (representing long-distance migratory rates of up to 44 km/day). All PSATs were first detected in the Bay of Fundy. Tags that released in February and April were found 5–21 km offshore of the Saint John Harbour, while tags that released in June were first detected in near shore areas throughout the Bay of Fundy. The substrate at winter tag release locations (estimated from backward numerical particle-tracking experiments) consisted primarily of moraines and postglacial mud substrate with low backscatter strength, indicative of soft or smooth seabed. Based on the proximity of winter tag release locations, the consistent depths observed between fish, and previous research, it is suspected that a winter aggregation exists in the Bay of Fundy. This study expands the understanding of the marine distribution and range of Atlantic sturgeon on the east coast of Canada. PMID:27043209

  18. Oceanic Distribution, Behaviour, and a Winter Aggregation Area of Adult Atlantic Sturgeon, Acipenser oxyrinchus oxyrinchus, in the Bay of Fundy, Canada.

    PubMed

    Taylor, Andrew Douglas; Ohashi, Kyoko; Sheng, Jinyu; Litvak, Matthew Kenneth

    2016-01-01

    Seasonal distribution of adult Atlantic sturgeon was examined using pop-up satellite archival tags (PSATs) and ultrasonic transmitters deployed in the Saint John River, New Brunswick, Canada. Seven MK10 PSATs programmed for release in June 2012 and seven MiniPAT PSATs programmed for release in February and April 2013 were deployed in August 2011 and 2012, respectively. Eleven of 14 PSATs surfaced and transmitted depth and temperature data archived for the duration of their deployment (121-302 days). Among these eleven PSATs, five were recovered and 15-sec archival data was downloaded. Following exit from the Saint John River in the fall, tagged fish occupied a mean monthly depth of 76.3-81.6 m at temperatures as low as 4.9˚C throughout the winter before returning to shallower areas in the spring. The majority of ultrasonic detections occurred in the Bay of Fundy, but fish were detected as far as Riviere Saint-Jean, Quebec, approximately 1500 km from the Bay of Fundy (representing long-distance migratory rates of up to 44 km/day). All PSATs were first detected in the Bay of Fundy. Tags that released in February and April were found 5-21 km offshore of the Saint John Harbour, while tags that released in June were first detected in near shore areas throughout the Bay of Fundy. The substrate at winter tag release locations (estimated from backward numerical particle-tracking experiments) consisted primarily of moraines and postglacial mud substrate with low backscatter strength, indicative of soft or smooth seabed. Based on the proximity of winter tag release locations, the consistent depths observed between fish, and previous research, it is suspected that a winter aggregation exists in the Bay of Fundy. This study expands the understanding of the marine distribution and range of Atlantic sturgeon on the east coast of Canada.

  19. Phylogeography of the European sturgeon (Acipenser sturio): A critically endangered species.

    PubMed

    Chassaing, Olivier; Desse-Berset, Nathalie; Hänni, Catherine; Hughes, Sandrine; Berrebi, Patrick

    2016-01-01

    The European sturgeon (Acipenser sturio) was once a common species throughout Europe, but the sole remaining natural population presently inhabits the Gironde Estuary in France (Atlantic coast). The species was classified as 'Critically Endangered' in 1996, and the Gironde population is now on the verge of extinction. In this setting, and for the first time, we present the past phylogeographical features of this species throughout Europe along with an assessment of its former genetic diversity. This study was based on a molecular analysis (mtDNA CR sequencing) of 10 living specimens from the Gironde Estuary, 55 museum specimens that had been caught along 19th and 20th centuries, and 59 archaeological remains dating back to 260-5000years BP, from which mitochondrial DNA was extracted and amplified. Although discontinuous, the produced data provided a realistic image of the former structure of A. sturio in Europe. Reconstruction of the phylogenetic trees and haplotypes network led to the identification of several clades. The mitochondrial genetic diversity of this species was found to be much greater at the core (Iberian Peninsula, Mediterranean and Adriatic regions) than along the margins (Atlantic-Northern Europe, Black Sea) of its range. A series of hypotheses on the dates and causes of changes in the species' major structures are put forward on the basis of these data. Finally, competition with A. oxyrinchus, a sibling species whose presence in Northern Europe was recently reconsidered, is presented as a major factor in the evolution of this species.

  20. Evolutionary relations and population differentiation of Acipenser gueldenstaedtii Brandt, Acipenser persicus Borodin, and Acipenser baerii Brandt

    PubMed Central

    Sergeev, Alexey A.

    2016-01-01

    Russian ( Acipenser gueldenstaedtii), Persian ( A. persicus) and Siberian ( A. baerii) sturgeons are closely related ‘Ponto-Caspian’ species. Investigation of their population structure is an important problem, the solution of which determines measures for conservation of these species. According to previous studies, ‘baerii-like’ mitochondrial genotypes were found in the Caspian Sea among 35% of Russian sturgeon specimens, but were not found in Persian sturgeons. This confirms genetic isolation of the Persian sturgeon from the Russian sturgeon in the Caspian Sea. However, in order to clarify the relationships of these species it is necessary to analyze nuclear DNA markers. The amplified fragment length polymorphism (method) allows estimating interpopulation and interspecific genetic distances using nuclear DNA markers. In the present study, four samples were compared: Persian sturgeons from the South Caspian Sea, Russian sturgeons from the Caspian Sea and the Sea of Azov, and Siberian sturgeons from the Ob’ River, which are close to the latter two species, but are also clearly morphologically and genetically distinct from them. For the amplified fragment length polymorphism (AFLP) method, eight pairs of selective primers were used. The analysis revealed that the Siberian sturgeon has formed a separate branch from the overall Persian-Russian sturgeons cluster, which was an expected result. In addition, the results showed that the Caspian Russian sturgeon is closer to the Persian sturgeon from the Caspian Sea than to the Russian Sturgeon from the Sea of Azov. The present DNA marker data confirm that despite the genetic isolation of the Persian sturgeon from the Russian sturgeon in the Caspian Sea, the Persian sturgeon is a young species. PMID:28003882

  1. The complete mitochondrial genome of the shortfin mako, Isurus oxyrinchus (Chondrichthyes, Lamnidae).

    PubMed

    Chang, Chia-Hao; Shao, Kwang-Tsao; Lin, Yeong-Shin; Tsai, An-Yi; Su, Pin-Xuan; Ho, Hsuan-Ching

    2015-06-01

    The complete mitochondrial genome of the shortfin mako (Isurus oxyrinchus) was determined by using a PCR-based method. The total length of mitochondrial DNA is 16,701 bp and includes 13 protein-coding genes, 2 ribosomal RNA, 22 transfer RNA genes, 1 replication origin region, and 1 control region. The mitochondrial gene arrangement of the tiger tail seahorse is also matching the one observed in the most vertebrate creatures. Base composition of the genome is A (28.8%), T (28.0%), C (28.0%), and G (15.2%) with an A + T rich hallmark as that of other vertebrate mitochondrial genomes.

  2. Intersex gonad differentiation in cultured Russian (Acipenser gueldenstaedtii) and Siberian (Acipenser baerii) sturgeon.

    PubMed

    Rzepkowska, Malgorzata; Ostaszewska, Teresa; Gibala, Monika; Roszko, Marek Lukasz

    2014-02-01

    Among sturgeons, the occurrence of individuals with gonads containing both testis and ovary components is considered pathological, and such fish are described as intersex individuals or intersexes. Intersexes are observed in both wild and cultured populations of sturgeon, usually at low frequencies. In the present study, intersex Russian (Acipenser gueldenstaedtii) and Siberian (Acipenser baerii) sturgeons constituted 30% of the studied populations. Macroscopically, intersex gonads were recognizable from 500 days posthatching (dph). Initially, gonads with predominantly male characteristics (testis-ova) were observed, but in older fish gonads with predominantly female traits (ova-testis) were more frequent. Using microscopic analysis, intersex gonads were discernible by 130-200 dph. Observations of intersex germinal epithelium development and analysis of sex distribution in the study populations indicated that feminization was occurring. Histological analysis revealed that differentiation of the germinal epithelium in such gonads was accompanied by various morphological alterations (transformations) that were described using quantitative and localization criteria. The most common type of transformations, massive subepithelial transformations, was manifested by the presence of abundant female germinal tissue located under the gonad surface epithelium in the developing testis. These transformations were identified in the early development stage (100-200 dph). In this type of transformation, differentiation of female germinal tissue at the gonad surface and male tissue at the mesorchium/mesovarium resulted in complete formation of both male and female germinal epithelia within the same gonad.

  3. Unexpected Headless and Tailless Fish in the Stomach Content of Shortfin Mako Isurus oxyrinchus

    PubMed Central

    Biton Porsmoguer, Sebastián; Bănaru, Daniela; Béarez, Philippe; Dekeyser, Ivan; Merchán Fornelino, Manuel; Boudouresque, Charles F.

    2014-01-01

    The stomach content of 113 individuals of shortfin mako Isurus oxyrinchus was analyzed. Individuals were sampled at landing in Vigo (Spain) and captured by sea-surface long-liners in the vicinity of the Azores Archipelago and between Azores and the Iberian Peninsula, in March and October 2012, and March 2013. Teleosts constituted the dominant item, mainly Atlantic saury Scomberesox saurus (87% of teleost prey). Among them, 94% were deprived of both head and the caudal fin, while the flesh and bones of the body were preserved. The presence of eye's lenses, the number of which was consistent with the number of fish remains, likely rules out the elimination of the heads before ingestion. There is no obvious explanation for this unexpected and unrecorded pattern of digestion. PMID:24533093

  4. Oviducal gland microstructure of Raja miraletus and Dipturus oxyrinchus (Elasmobranchii, Rajidae).

    PubMed

    Marongiu, Martina F; Porcu, Cristina; Bellodi, Andrea; Cuccu, Danila; Mulas, Antonello; Follesa, Maria C

    2015-11-01

    We studied the morphology and histology of the oviducal gland (OG) in the brown ray (Raja miraletus) and the long-nosed skate (Dipturus oxyrinchus) to understand its functional role in the reproductive strategy of these species. The external morphology of the gland was similar in both species, with lateral extensions like those found in other members of the Rajidae. Microscopic analysis showed a similar internal organization in both species. Immature and developing glands did not react to histochemical techniques. On reaching maturity, the OG had the largest width due to an increase in the production of secretory materials. In both species, the club zone of the gland showed a strong reaction to Periodic acid-Schiff (PAS) and alcian blue (AB) stains, indicating production of neutral and sulfated acid mucins. The secretory material produced by the papillary zone varied greatly between the two species. Both displayed tubular glands similar to those observed in the club zone, but in D. oxyrinchus the region near the lumen was intensely PAS+, whereas the last row of tubules of the brown ray stained intensely for a mixture of neutral and sulfated mucins. The baffle zone was the most conspicuous and extensive segment of all OGs, and it did not react to PAS/AB. The terminal zone, which is responsible for production of hair filaments, differed between the two species in terms of composition and organization of serous and mucous glands. This difference probably is related to the different substrates in which they release the egg capsules. Individual sperm detected in the brown ray baffle lamellae could be the result of a recent mating, whereas their presence in the deep recesses of the baffle and in the terminal zone of the long-nosed skate might indicate sperm storage.

  5. Oxidative stress indicators and trace element concentrations in tissues of mako shark (Isurus oxyrinchus).

    PubMed

    Vélez-Alavez, Marcela; Labrada-Martagón, Vanessa; Méndez-Rodriguez, Lía C; Galván-Magaña, Felipe; Zenteno-Savín, Tania

    2013-08-01

    Liver, kidney and muscle from juvenile mako sharks (Isurus oxyrinchus) were collected in Baja California Sur. Lead (Pb), cadmium (Cd), mercury (Hg) and arsenic (As) concentrations were determined by atomic absorption spectrophotometry. The production of superoxide radical (O2(•-)) was measured as an indicator of reactive oxygen species production; lipid peroxidation (TBARS) and protein carbonyl levels were quantified as indicators of oxidative damage, and the activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione-S-transferase (GST) was assessed as indicator of antioxidant defenses. Two discriminant functions separated muscle from liver and kidney samples. Cd concentration was lower in muscle than in kidney (p<0.05) and Hg concentration was higher in muscle than in liver and kidney (p<0.05). Although GR and SOD activities were higher, oxidative damage (TBARS and carbonyl protein levels) was also higher in kidney (p<0.05). SOD activity, TBARS levels, and Cd and Hg concentration were the set of predictors with significant relevance during tissue discrimination. Tissue metabolism, physiology of the organisms and environmental factors may be related to the differences in trace elements and oxidative stress indicators found in muscle, liver and kidney of the mako shark.

  6. Intestinal helminth fauna of the shortfin mako Isurus oxyrinchus (Elasmobranchii: Lamnidae) in the northeast Atlantic Ocean.

    PubMed

    Penadés-Suay, Jaime; Tomás, Jesús; Merchán, Manuel; Aznar, Francisco Javier

    2017-02-08

    Large oceanic sharks represent a suitable model to investigate the influence of a host's oceanic conditions on the structure of its helminth communities. In this study, we describe the intestinal helminth fauna, and investigate determinants of infracommunity structure, in 39 specimens of shortfin mako Isurus oxyrinchus collected in the NE Atlantic. Six cestode species were found in the spiral valve of makos: 3 are typical from lamnid sharks, namely, gravid specimens of Clistobothrium montaukensis, Gymnorhynchus isuri and Ceratobothrium xanthocephalum, and 3 are immature specimens of cestode species common to several elasmobranchs, namely, Dinobothrium septaria, Nybelinia lingualis, and Phyllobothrium cf. lactuca. In addition, L3 larvae of Anisakis sp. type I were detected. Infracommunities were species poor and had low total helminth abundance. The result of Schluter's variance ratio test was compatible with the hypothesis of independent colonization of helminth taxa. These results conform to previous studies on oceanic predators that have hypothesized that these hosts should have depauperate and unpredictable helminth infracommunities because oceanic conditions hamper parasite transmission. However, mean species richness and mean total abundance of cestodes of shortfin mako and other oceanic sharks did not significantly differ from those of elasmobranchs from other habitats. This suggests that the large body size and prey consumption rates of oceanic sharks offset the negative 'dilution' effect of oceanic habitat on transmission rates. Additionally, or alternatively, parasites of oceanic sharks may have expanded the use of intermediate hosts through the trophic web to spread out the risk of failure to complete their life cycles.

  7. Scale morphology and flexibility in the shortfin mako Isurus oxyrinchus and the blacktip shark Carcharhinus limbatus.

    PubMed

    Motta, Philip; Habegger, Maria Laura; Lang, Amy; Hueter, Robert; Davis, Jessica

    2012-10-01

    We quantified placoid scale morphology and flexibility in the shortfin mako Isurus oxyrinchus and the blacktip shark Carcharhinus limbatus. The shortfin mako shark has shorter scales than the blacktip shark. The majority of the shortfin mako shark scales have three longitudinal riblets with narrow spacing and shallow grooves. In comparison, the blacktip shark scales have five to seven longitudinal riblets with wider spacing and deeper grooves. Manual manipulation of the scales at 16 regions on the body and fins revealed a range of scale flexibility, from regions of nonerectable scales such as on the leading edge of the fins to highly erectable scales along the flank of the shortfin mako shark body. The flank scales of the shortfin mako shark can be erected to a greater angle than the flank scales of the blacktip shark. The shortfin mako shark has a region of highly flexible scales on the lateral flank that can be erected to at least 50°. The scales of the two species are anchored in the stratum laxum of the dermis. The attachment fibers of the scales in both species appear to be almost exclusively collagen, with elastin fibers visible in the stratum laxum of both species. The most erectable scales of the shortfin mako shark have long crowns and relatively short bases that are wider than long. The combination of a long crown length to short base length facilitates pivoting of the scales. Erection of flank scales and resulting drag reduction is hypothesized to be passively driven by localized flow patterns over the skin.

  8. Fertilization success of sterlet Acipenser ruthenus and Siberian sturgeon Acipenser baerii gametes under conditions of heterospecific mating.

    PubMed

    Havelka, M; Šachlová, H; Shaliutina-Kolešová, A; Rodina, M

    2016-11-01

    Species may be prevented from interspecific hybridization by a number of different reproductive barriers that operate precopulatory and postcopulatory. In situation, when natural precopulatory reproductive barriers are affected by anthropogenic factors, postcopulatory reproductive barriers may be important for maintaining gametic isolation and hence preventing interspecific hybridization. This is highly topical in sturgeon (order Acipenseriformes) which exhibits remarkable ease of interspecific hybridization. The objectives of the present study were to evaluate the fertilization success of Acipenser ruthenus and Acipenser baerii spermatozoa under the interspecific competitive conditions and assessed, whether their spermatozoa tend to differentially fertilize eggs of conspecifics. We set up several in vitro fertilization experiments: (i) pooled eggs of both species were fertilized by sperm of each species separately; (ii) eggs of each species were fertilized by pooled sperm; (iii) pooled eggs were fertilized by pooled sperm and (iv) purebred and hybrid control groups. Using parental assignment by molecular markers, we found that when these species competed in pooled sperm, 78.9% of progeny were sired by A. ruthenus and 21.1% by A. baerii, demonstrating higher fertilization success for the former, irrespective of conspecificity of fertilized eggs. When pooled eggs were inseminated by A. ruthenus or A. baerii sperm separately, progeny almost equally comprised hybrid and purebred individuals. Hence, neither A. ruthenus nor A. baerii eggs showed a tendency to biased fertilization by spermatozoa of conspecific males. These findings together show that there may not be postcopulatory mechanisms preventing hybridization between A. ruthenus and A. baerii.

  9. The complete mitochondrial genome of Chinese sturgeon (Acipenser sinensis).

    PubMed

    Liao, Xiaolin; Tian, Hua; Zhu, Bin; Chang, Jianbo

    2016-01-01

    The complete mitochondrial genome of Chinese sturgeon (Acipenser sinensis) was determined by direct sequencing of PCR products. The Chinese sturgeon mitochondrial DNA is a circular molecule (16,688 bp in length) with the typical gene arrangement of vertebrate mtDNA, containing 13 protein-coding genes, two ribosomal RNA and 22 transfer RNA genes, and a non-coding control region. Its control region contains 4.5 copies of unit with 82 bp long at 5' end, which has been reported before for this species. Phylogenetic tree based on 13 protein-coding genes confirmed that the complete mtDNA sequence of Chinese sturgeon was reported here for the first time.

  10. Toxicity assessment of silver nanoparticles in Persian sturgeon (Acipenser persicus) and starry sturgeon (Acipenser stellatus) during early life stages.

    PubMed

    Banan, Ashkan; Kalbassi Masjed Shahi, Mohammad Reza; Bahmani, Mahmoud; Yazdani Sadati, Mohammad Ali

    2016-05-01

    Silver nanoparticles (AgNPs) are widely used in consumer products mainly due to their antimicrobial action. The rapidly increasing use of nanoparticles (NPs) has driven more attention to their possible ecotoxicological effects. In this study, the acute toxicity of colloidal AgNPs was evaluated during the embryonic stage of Persian sturgeon (Acipenser persicus) and starry sturgeon (Acipenser stellatus) at concentrations of 0, 0.25, 0.5, 1, 2, 4, and 8 mg/L. Fertilized eggs (75 eggs per replicate) were exposed to aforementioned concentrations for 96 h in triplicate. 96-h LC50 values in Persian sturgeon and starry sturgeon were calculated as 0.163 and 0.158 mg/L, respectively. Furthermore, in starry sturgeon, the short-term effects of AgNPs on the hatching rate, survival rate, and Ag accumulation during early life stages (before active feeding commences) were also analyzed at concentrations of 0, 0.025, 0.05, and 0.1 mg/L of colloidal AgNPs. The highest silver accumulation occurred in larvae exposed to 0.1 mg/L AgNPs; however, the body burden of silver did not alter survival rate, and there were no significant differences among treatments. Based on the obtained results from the acute toxicity exposures, AgNPs induced a concentration-dependent toxicity in both species during early life stages, while complementary studies are suggested for investigating their short-term effects in detail.

  11. Identification and response to metals of metallothionein in two ancient fishes: white sturgeon (Acipenser transmontanus) and lake sturgeon (Acipenser fulvescens).

    PubMed

    Doering, Jon A; Beitel, Shawn C; Eisner, Bryanna K; Heide, Timon; Hollert, Henner; Giesy, John P; Hecker, Markus; Wiseman, Steve B

    2015-05-01

    White sturgeon (Acipenser transmontanus) are among the most sensitive species of fishes to Cu, Cd, and Zn, but there is no information about sensitivity of lake sturgeon (Acipenser fulvescens). To begin to elucidate molecular mechanism(s) of sensitivity of sturgeons to metals a cDNA encoding metallothionein (MT) was amplified from livers of white sturgeon (WS-MT) and lake sturgeon (LS-MT), and expression in response to Cu, Cd, or Zn was characterized in liver explants from each species. The primary structure of WS-MT and LS-MT contained 20 cysteine residues, which is the same as MTs of teleost fishes. However, the primary structure of WS-MT and LS-MT contained 63 amino acids, which is longer than any MT identified in teleost fishes. Abundance of transcripts of WS-MT in explants exposed to 0.3, 3, 30, or 100 μg/L of Cu was 1.7-, 1.7-, 2.1-, and 2.6-fold less than in controls, respectively. In contrast, abundances of transcripts of WS-MT were 3.3- and 2.4-fold greater in explants exposed to 30 μg/L of Cd and 1000 μg/L of Zn, respectively. Abundance of transcripts of LS-MT was not significantly different at any concentration of Cu, Cd, or Zn. MT is hypothesized to represent a critical mechanism for detoxification of metals. Therefore, results of this study suggest that sensitivity of sturgeons to exposure to Cu, Cd, or Zn might be a result of the relatively lesser maximal response of MT to metals. The study also suggestslake sturgeon might be more sensitive than white sturgeon to metals.

  12. Gulf sturgeon spawning migration and habitat in the Choctawhatchee River system, Alabama-Florida

    USGS Publications Warehouse

    Fox, D.A.; Hightower, J.E.; Parauka, F.M.

    2000-01-01

    Information about spawning migration and spawning habitat is essential to maintain and ultimately restore populations of endangered and threatened species of anadromous fish. We used ultrasonic and radiotelemetry to monitor the movements of 35 adult Gulf sturgeon Acipenser oxyrinchus desotoi (a subspecies of the Atlantic sturgeon A. oxyrinchus) as they moved between Choctawhatchee Bay and the Choctawhatchee River system during the spring of 1996 and 1997. Histological analysis of gonadal biopsies was used to determine the sex and reproductive status of individuals. Telemetry results and egg sampling were used to identify Gulf sturgeon spawning sites and to examine the roles that sex and reproductive status play in migratory behavior. Fertilized Gulf sturgeon eggs were collected in six locations in both the upper Choctawhatchee and Pea rivers. Hard bottom substrate, steep banks, and relatively high flows characterized collection sites. Ripe Gulf sturgeon occupied these spawning areas from late March through early May, which included the interval when Gulf sturgeon eggs were collected. For both sexes, ripe fish entered the Choctawhatchee River significantly earlier and at a lower water temperature and migrated further upstream than did nonripe fish. Males entered the Choctawhatchee River at a lower water temperature than females. Results from histology and telemetry support the hypothesis that male Gulf sturgeon may spawn annually, whereas females require more than 1 year between spawning events. Upper river hard bottom areas appear important for the successful spawning of Gulf sturgeon, and care should be taken to protect against habitat loss or degradation of known spawning habitat.

  13. Fertility of a spontaneous hexaploid male Siberian sturgeon, Acipenser baerii

    PubMed Central

    2014-01-01

    Background Evolution of sturgeons and paddlefishes (order Acipenseriformes) is inherently connected with polyploidization events which resulted in differentiation of ploidy levels and chromosome numbers of present acipenseriform species. Moreover, allopolyploidization as well as autopolyploidization seems to be an ongoing process in these fishes and individuals with abnormal ploidy levels were occasionally observed within sturgeon populations. Here, we reported occurrence of Siberian sturgeon (Acipenser baerii) male with abnormal ploidy level for this species, accessed its ploidy level and chromosome number and investigate its potential sterility or fertility in comparison with normal individuals of sterlet (A. ruthenus), Russian sturgeon (A. gueldenstaedtii) and Siberian sturgeon (A. baerii). Results Acipenser ruthenus possessed 120 chromosomes, exhibiting recent diploidy (2n), A. gueldenstaedtii and A. baerii had ~245 chromosomes representing recent tetraploidy (4n), and A. baerii male with abnormal ploidy level had ~ 368 chromosomes, indicating recent hexaploidy (6n). Genealogy assessed from the mtDNA control region did not reveal genome markers of other sturgeon species and this individual was supposed to originate from spontaneous 1.5 fold increment in number of chromosome sets with respect to the number most frequently found in nature for this species. Following hormone stimulation, the spontaneous hexaploid male produced normal sperm with ability for fertilization. Fertilization of A. baerii and A. gueldenstaedtii ova from normal 4n level females with sperm of the hexaploid male produced viable, non-malformed pentaploid (5n) progeny with a ploidy level intermediate to those of the parents. Conclusion This study firstly described occurrence of hexaploid individual of A. baerii and confirmed its autopolyploid origin. In addition to that, the first detailed evidence about fertility of spontaneous hexaploid sturgeon was provided. If 1.5 fold increment in

  14. Parasitic infection in various stages life of cultured Acipenser persicus

    PubMed Central

    Adel, Milad; Safari, Reza; Yaghoubzadeh, Zahra; Fazli, Hassan; Khalili, Elham

    2016-01-01

    The present study was conducted to evaluate the status of the parasite fauna in Acipenser persicus at different development stages, in order to find prevention protocols for parasitic diseases in this valuable species. For this purpose, sampling from each sex breeder, 10 egg samples, 5-day-old larvae (n = 20), 20-day-old larvae (n = 80) and fingerling of A. persicus (n = 60) released in earthen ponds were done. After the bioassay and preparing wet mount from the internal and external organs, identification was done according to the keys. According to the results, no fauna parasites were isolated from egg samples and 5-day-old larvae; but Trichodina spp. was isolated from 20-day-old larvae. Also, the same protozoan was isolated from fingerling released in earthen ponds, the mean intensity, prevalence and range of contamination by fingerling were higher with compared to 20-day-old larvae. Trichodina sp. and Diplostomum spathaceum were isolated from skin and eyes of females, respectively. However, Trichodina sp. and Ichthyophthirius multifiliis were isolated from skin of male breeders. In this study, no parasites were isolated from internal organs of larves and fingerling but four intestinal parasites included: Cucullanus sphaerocephlaus, Anisakis sp., Skyrjabinopsilus semiarmatus, and Lepto-rhynchoides plagicephalu were isolated from internal organs of breeder. Based on a wide range of parasitic infection observed in various life stages of A. persicus, it seems necessary to consider hygienic and management measures. PMID:27226891

  15. Parasitic infection in various stages life of cultured Acipenser persicus.

    PubMed

    Adel, Milad; Safari, Reza; Yaghoubzadeh, Zahra; Fazli, Hassan; Khalili, Elham

    2016-01-01

    The present study was conducted to evaluate the status of the parasite fauna in Acipenser persicus at different development stages, in order to find prevention protocols for parasitic diseases in this valuable species. For this purpose, sampling from each sex breeder, 10 egg samples, 5-day-old larvae (n = 20), 20-day-old larvae (n = 80) and fingerling of A. persicus (n = 60) released in earthen ponds were done. After the bioassay and preparing wet mount from the internal and external organs, identification was done according to the keys. According to the results, no fauna parasites were isolated from egg samples and 5-day-old larvae; but Trichodina spp. was isolated from 20-day-old larvae. Also, the same protozoan was isolated from fingerling released in earthen ponds, the mean intensity, prevalence and range of contamination by fingerling were higher with compared to 20-day-old larvae. Trichodina sp. and Diplostomum spathaceum were isolated from skin and eyes of females, respectively. However, Trichodina sp. and Ichthyophthirius multifiliis were isolated from skin of male breeders. In this study, no parasites were isolated from internal organs of larves and fingerling but four intestinal parasites included: Cucullanus sphaerocephlaus, Anisakis sp., Skyrjabinopsilus semiarmatus, and Lepto-rhynchoides plagicephalu were isolated from internal organs of breeder. Based on a wide range of parasitic infection observed in various life stages of A. persicus, it seems necessary to consider hygienic and management measures.

  16. Spawning by lake sturgeon (Acipenser fulvescens) in the Detroit River

    USGS Publications Warehouse

    Caswell, N.M.; Peterson, D.L.; Manny, B.A.; Kennedy, G.W.

    2004-01-01

    Overfishing and habitat destruction in the early 1900s devastated lake sturgeon (Acipenser fulvescens) populations in the Great Lakes. Although a comprehensive restoration strategy for this species was recently drafted by the Michigan Department of Natural Resources, a lack of current data on Great Lakes sturgeon stocks has hindered rehabilitation efforts. Historically, the Detroit River supported one of the largest lake sturgeon populations in the Great Lakes; however, little is known about the current population or its habitat use. The main objective of this study was to determine if lake sturgeon spawns in the Detroit River. As part of a larger study, baited setlines were used to capture lake sturgeon in the Detroit River in the spring and summer of 2000 and 2001. In each year of the study, ultrasonic transmitters were surgically implanted in 10 adult fish to track their movements, evaluate habitat use and identify possible spawning sites. Using telemetry and egg mats to verify spawning activity, one spawning site was located and verified in the Detroit River. Spawning was verified by recovering sturgeon eggs deposited on egg collection mats anchored at the site. Telemetry data suggested that several other possible spawning sites also may exist, however, spawning activity was not verified at these sites.

  17. Structural characteristics and development of ampullary organs in Acipenser naccarii.

    PubMed

    Camacho, Susana; Ostos, Maria Del Valle; Llorente, José Ignacio; Sanz, Ana; García, Manuel; Domezain, Alberto; Carmona, Ramón

    2007-09-01

    Ampullary organs of Acipenser naccarii sturgeons were examined by optical and electronic microscopy (transmission electron microscopy and scanning electron microscopy) from hatching until 1 month later when the juvenile phase is completely established. It was observed that, when A. naccarii begins to feed actively, the ultrastructural characteristics of ampullary organs already correspond to those of adult animals. These organs may, therefore, be functional and, together with taste buds, facilitate food search after exhaustion of yolk sac food reserves. Mature ampullary organs of A. naccarii are formed by an ampulla that communicates with the exterior by means of a short channel. These ampullae correspond to the sensory portion of these receptors and are formed by two cell types: receptor cells and support cells. Receptor cells present a kinocilium on their free surface and establish ribbon synapses with axon nerve endings that arise from the underlying conjunctive tissue. Support cells enclose receptor cells, bear stereocilia and occasional cilia, and are of a secretory nature. The mucus associated with ampullary organs mainly comprises neutral mucopolysaccharides, whereas mucopolysaccharides are usually acid in other fish groups.

  18. 78 FR 32623 - Endangered Species; File No. 17452

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-31

    ... permit to take shortnose (Acipenser brevirostrum) and Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus... shortnose sturgeon. For each species, up to 20 adult and juvenile animals would be collected annually using gill nets. Once captured, sturgeon would be measured, weighed, tissue sampled, and passive...

  19. Composition of Glycosaminoglycans in Elasmobranchs including Several Deep-Sea Sharks: Identification of Chondroitin/Dermatan Sulfate from the Dried Fins of Isurus oxyrinchus and Prionace glauca

    PubMed Central

    Higashi, Kyohei; Takeuchi, Yoshiki; Mukuno, Ann; Tomitori, Hideyuki; Miya, Masaki; Linhardt, Robert J.; Toida, Toshihiko

    2015-01-01

    Shark fin, used as a food, is a rich source of glycosaminoglyans (GAGs), acidic polysaccharides having important biological activities, suggesting their nutraceutical and pharmaceutical application. A comprehensive survey of GAGs derived from the fin was performed on 11 elasmobranchs, including several deep sea sharks. Chondroitin sulfate (CS) and hyaluronic acid (HA) were found in Isurus oxyrinchus, Prionace glauca, Scyliorhinus torazame, Deania calcea, Chlamydoselachus anguineus, Mitsukurina owatoni, Mustelus griseus and Dasyatis akajei, respectively. CS was only found from Chimaera phantasma, Dalatias licha, and Odontaspis ferox, respectively. Characteristic disaccharide units of most of the CS were comprised of C- and D-type units. Interestingly, substantial amount of CS/dermatan sulfate (DS) was found in the dried fin (without skin and cartilage) of Isurus oxyrinchus and Prionace glauca. 1H-NMR analysis showed that the composition of glucuronic acid (GlcA) and iduronic acid (IdoA) in shark CS/DS was 41.2% and 58.8% (Isurus oxyrinchus), 36.1% and 63.9% (Prionace glauca), respectively. Furthermore, a substantial proportion of this CS/DS consisted of E-, B- and D-type units. Shark CS/DS stimulated neurite outgrowth of hippocampal neurons at a similar level as DS derived from invertebrate species. Midkine and pleiotrophin interact strongly with CS/DS from Isurus oxyrinchus and Prionace glauca, affording Kd values of 1.07 nM, 6.25 nM and 1.70 nM, 1.88 nM, respectively. These results strongly suggest that the IdoA-rich domain of CS/DS is required for neurite outgrowth activity. A detailed examination of oligosaccharide residues, produced by chondroitinase ACII digestion, suggested that the IdoA and B-type units as well as A- and C-type units were found in clusters in shark CS/DS. In addition, it was discovered that the contents of B-type units in these IdoA-rich domain increased in a length dependent manner, while C- and D-type units were located particularly in the

  20. Composition of glycosaminoglycans in elasmobranchs including several deep-sea sharks: identification of chondroitin/dermatan sulfate from the dried fins of Isurus oxyrinchus and Prionace glauca.

    PubMed

    Higashi, Kyohei; Takeuchi, Yoshiki; Mukuno, Ann; Tomitori, Hideyuki; Miya, Masaki; Linhardt, Robert J; Toida, Toshihiko

    2015-01-01

    Shark fin, used as a food, is a rich source of glycosaminoglyans (GAGs), acidic polysaccharides having important biological activities, suggesting their nutraceutical and pharmaceutical application. A comprehensive survey of GAGs derived from the fin was performed on 11 elasmobranchs, including several deep sea sharks. Chondroitin sulfate (CS) and hyaluronic acid (HA) were found in Isurus oxyrinchus, Prionace glauca, Scyliorhinus torazame, Deania calcea, Chlamydoselachus anguineus, Mitsukurina owatoni, Mustelus griseus and Dasyatis akajei, respectively. CS was only found from Chimaera phantasma, Dalatias licha, and Odontaspis ferox, respectively. Characteristic disaccharide units of most of the CS were comprised of C- and D-type units. Interestingly, substantial amount of CS/dermatan sulfate (DS) was found in the dried fin (without skin and cartilage) of Isurus oxyrinchus and Prionace glauca. 1H-NMR analysis showed that the composition of glucuronic acid (GlcA) and iduronic acid (IdoA) in shark CS/DS was 41.2% and 58.8% (Isurus oxyrinchus), 36.1% and 63.9% (Prionace glauca), respectively. Furthermore, a substantial proportion of this CS/DS consisted of E-, B- and D-type units. Shark CS/DS stimulated neurite outgrowth of hippocampal neurons at a similar level as DS derived from invertebrate species. Midkine and pleiotrophin interact strongly with CS/DS from Isurus oxyrinchus and Prionace glauca, affording Kd values of 1.07 nM, 6.25 nM and 1.70 nM, 1.88 nM, respectively. These results strongly suggest that the IdoA-rich domain of CS/DS is required for neurite outgrowth activity. A detailed examination of oligosaccharide residues, produced by chondroitinase ACII digestion, suggested that the IdoA and B-type units as well as A- and C-type units were found in clusters in shark CS/DS. In addition, it was discovered that the contents of B-type units in these IdoA-rich domain increased in a length dependent manner, while C- and D-type units were located particularly in the

  1. EFFECT OF CRYOPRESERVATION AND THEOPHYLLINE ON MOTILITY CHARACTERISTICS OF LAKE STURGEON (ACIPENSER FULVESCENS) SPERMATOZOA

    EPA Science Inventory

    Computer-assisted motility analysis (CASA) was used to evaluate the effect of cryopreservation and theophylline treatment on sperm motility of lake sturgeon (Acipenser fulvescens).Motility was recorded at 0 and 5 min postactivation.The effect of cryopreservation on sperm acrosin-...

  2. OBJECTIVE ANALYSIS OF SPERM MOTILITY IN THE LAKE STURGEON, ACIPENSER FULVESCENS: ACTIVATION AND INHIBITION CONDITIONS

    EPA Science Inventory

    An objective analysis of the duration of motility of sperm from the lake sturgeon, Acipenser fulvescens, has been performed using computer-assisted sperm motion analysis at 200 frames/s. Motility was measured in both 1993 and 1994. The percentage of activated motile sperm and the...

  3. A comparative gene index for the white sturgeon Acipenser transmontanus.

    PubMed

    Lazzari, Barbara; Mariani, Valentina; Malinverni, Roberto; Caprera, Andrea; Giuffra, Elisabetta

    2008-03-01

    Sturgeons are archaic fishes phylogenetically distinct from Teleosts. They represent an important niche for aquaculture, particularly for the production of caviar and high quality fillets, while many natural populations in various world areas are today threatened by extinction. Knowledge of the sturgeon genome is limited, as it is the case of many other species of interest for fishery, aquaculture and conservation. Sequences from non-normalized libraries of skin and spleen of the American sturgeon (A. transmontanus) produced in our laboratories were analysed via a bioinformatic procedure, and compared to similar resources available for three Teleost species. Data collected during the analyses were stored in a database - the Sturgeon database (db) - that can be queried via a web interface. The Sturgeon db contains a total of 16,404 sequences from Acipenser transmontanus, Ictalurus punctatus, Salmo salar and Takifugu rubripes, each specie being represented by expressed sequence tags (ESTs) from skin and spleen. Data contained in the database are the results of a number of analyses that mostly focus on sequence annotation and intra- and inter-species comparison. Putative SNP sites, tandem repeats, and sequences matching known protein patterns and motifs were also identified. The Sturgeon db is by now the only online resource dedicated to the analysis of A. transmontanus EST sequences, and represents a starting point for the investigation of the genome of sturgeons from a physiological perspective; it will be used to identify polymorphic markers to study, for example, fish pathologies or to survey fish disease resistance, and to produce gene expression arrays. Introduction of sequences from other species in the analysis pipeline allowed inter-species comparisons of transcripts distribution in Gene Ontology categories, as well as orthologs identification, despite the high sturgeon phylogenetic distance from other fish species. As a result of the EST analysis procedure

  4. High survivorship after catch-and-release fishing suggests physiological resilience in the endothermic shortfin mako shark (Isurus oxyrinchus)

    PubMed Central

    French, Robert P.; Lyle, Jeremy; Tracey, Sean; Currie, Suzanne; Semmens, Jayson M.

    2015-01-01

    The shortfin mako shark (Isurus oxyrinchus) is a species commonly targeted by commercial and recreational anglers in many parts of the developed world. In Australia, the species is targeted by recreational anglers only, under the assumption that most of the sharks are released and populations remain minimally impacted. If released sharks do not survive, the current management strategy will need to be revised. Shortfin mako sharks are commonly subjected to lengthy angling events; however, their endothermic physiology may provide an advantage over ectothermic fishes when recovering from exercise. This study assessed the post-release survival of recreationally caught shortfin mako sharks using Survivorship Pop-up Archival Transmitting (sPAT) tags and examined physiological indicators of capture stress from blood samples as well as any injuries that may be caused by hook selection. Survival estimates were based on 30 shortfin mako sharks captured off the south-eastern coast of Australia. Three mortalities were observed over the duration of the study, yielding an overall survival rate of 90%. All mortalities occurred in sharks angled for <30 min. Sharks experienced increasing plasma lactate with longer fight times and higher sea surface temperatures (SSTs), increased plasma glucose at higher SSTs and depressed expression of heat shock protein 70 and β-hydroxybutyrate at higher SSTs. Long fight times did not impact survival. Circle hooks significantly reduced foul hooking when compared with J hooks. Under the conditions of this study, we found that physical injury associated with hook choice is likely to have contributed to an increased likelihood of mortality, whereas the high aerobic scope associated with the species' endothermy probably enabled it to cope with long fight times and the associated physiological responses to capture. PMID:27303650

  5. Development of the skull and pectoral girdle in Siberian sturgeon, Acipenser baerii, and Russian sturgeon, Acipenser gueldenstaedtii (Acipenseriformes: Acipenseridae).

    PubMed

    Warth, Peter; Hilton, Eric J; Naumann, Benjamin; Olsson, Lennart; Konstantinidis, Peter

    2017-03-01

    The head is considered the major novelty of the vertebrates and directly linked to their evolutionary success. Its form and development as well as its function, for example in feeding, is of major interest for evolutionary biologists. In this study, we describe the skeletal development of the cranium and pectoral girdle in Siberian (Acipenser baerii) and Russian sturgeon (A. gueldenstaedtii), two species that are commonly farmed in aquaculture and increasingly important in developmental studies. This study comprises the development of the neuro-, viscero- and dermatocranium and the dermal and chondral components of the pectoral girdle, from first condensation of chondrocytes in prehatchlings to the early juvenile stage and reveals a clear pattern in formation. The otic capsules, the parachordal cartilages, and the trabeculae cranii are the first centers of chondrification, at 8.4mm TL. These are followed by the mandibular, then the hyoid, and later the branchial arches. Teeth form early on the dentary, dermopalatine, and palatopterygoid, and then appear later in the buccal cavity as dorsal and ventral toothplates. With ongoing chondrification in the neurocranium a capsule around the brain and a strong rostrum are formed. Dermal ossifications start to form before closure of the dorsal neurocranial fenestrae. Perichondral ossification of cartilage bones occurs much later in ontogeny. Our results contribute data bearing on the homology of elements such as the lateral rostral canal bone that we regard homologous to the antorbital of other actinopterygians based on its sequence of formation, position and form. We further raise doubts on the homology of the posterior ceratobranchial among Actinopteri based on the formation of the hyoid arch elements. We also investigate the basibranchials and the closely associated unidentified gill-arch elements and show that they are not homologous. J. Morphol. 278:418-442, 2017. © 2017 Wiley Periodicals, Inc.

  6. Biological characterization of the skin of shortfin mako shark Isurus oxyrinchus and preliminary study of the hydrodynamic behaviour through computational fluid dynamics.

    PubMed

    Díez, G; Soto, M; Blanco, J M

    2015-07-01

    This study characterized the morphology, density and orientation of the dermal denticles along the body of a shortfin mako shark Isurus oxyrinchus and identified the hydrodynamic parameters of its body through a computational fluid-dynamics model. The study showed a great variability in the morphology, size, shape, orientation and density of dermal denticles along the body of I. oxyrinchus. There was a significant higher density in dorsal and ventral areas of the body and their highest angular deviations were found in the lower part of the mouth and in the areas between the pre-caudal pit and the second dorsal and pelvic fins. A detailed three-dimensional geometry from a scanned body of a shark was carried out to evaluate the hydrodynamic properties such as drag coefficient, lift coefficient and superficial (skin) friction coefficient of the skin together with flow velocity field, according to different roughness coefficients simulating the effect of the dermal denticles. This preliminary approach contributed to detailed information of the denticle interactions. As the height of the denticles was increased, flow velocity and the effect of lift decreased whereas drag increased. The highest peaks of skin friction coefficient were observed around the pectoral fins.

  7. Population status of North American green sturgeon, Acipenser medirostris

    USGS Publications Warehouse

    Adams, P.B.; Grimes, C.; Hightower, J.E.; Lindley, S.T.; Moser, M.L.; Parsley, M.J.

    2007-01-01

    North American green sturgeon, Acipenser medirostris, was petitioned for listing under the Endangered Species Act (ESA). The two questions that need to be answered when considering an ESA listing are; (1) Is the entity a species under the ESA and if so (2) is the "species" in danger of extinction or likely to become an endangered species in the foreseeable future throughout all or a significant portion of its range? Green sturgeon genetic analyses showed strong differentiation between northern and southern populations, and therefore, the species was divided into Northern and Southern Distinct Population Segments (DPSs). The Northern DPS includes populations in the Rogue, Klamath-Trinity, and Eel rivers, while the Southern DPS only includes a single population in the Sacramento River. The principal risk factors for green sturgeon include loss of spawning habitat, harvest, and entrainment. The Northern DPS is not considered to be in danger of extinction or likely to become an endangered species in the foreseeable future. The loss of spawning habitat is not large enough to threaten this DPS, although the Eel River has been severely impacted by sedimentation due to poor land use practices and floods. The two main spawning populations in the Rogue and Klamath-Trinity rivers occupy separate basins reducing the potential for loss of the DPS through catastrophic events. Harvest has been substantially reduced and green sturgeon in this DPS do not face substantial entrainment loss. However there are significant concerns due to lack of information, flow and temperature issues, and habitat degradation. The Southern DPS is considered likely to become an endangered species in the foreseeable future. Green sturgeon in this DPS are concentrated into one spawning area outside of their natural habitat in the Sacramento River, making them vulnerable to catastrophic extinction. Green sturgeon spawning areas have been lost from the area above Shasta Dam on the Sacramento River and

  8. Swimming capability and swimming behavior of juvenile acipenser schrenckii.

    PubMed

    Cai, Lu; Taupier, Rachel; Johnson, David; Tu, Zhiying; Liu, Guoyong; Huang, Yingping

    2013-03-01

    Acipenser schrenckii, the Amur Sturgeon, was a commercially valuable fish species inhabiting the Amur (Heilongjiang) River but populations have rapidly declined in recent years. Dams impede A. schrenckii spawning migration and wild populations were critically endangered. Building fishways helped maintain fish populations but data on swimming performance and behavior was crucial for fishway design. To obtain such data on A. schrenckii, a laboratory study of juvenile A. schrenckii (n = 18, body mass = 32.7 ± 1.2 g, body length = 18.8 ± 0.3 cm) was conducted using a stepped velocity test carried out in a fish respirometer equipped with a high-speed video camera at 20°C. Results indicate: (1) The counter-current swimming capability of A. schrenckii was low with critical swimming speed of 1.96 ± 0.10 BL/sec. (2) When a linear function was fitted to the data, oxygen consumption, as a function of swimming speed, was determined to be MO2  = 337.29 + 128.10U (R(2)  = 0.971, P < 0.001) and the power value (1.0) of U indicated high swimming efficiency. (3) Excess post-exercise oxygen cost was 48.44 mgO2 /kg and indicated excellent fatigue recovery. (4) Cost of transport decreased slowly with increased swimming speed. (5) Increased swimming speed led to increases in the tail beat frequency and stride length. This investigation contributed to the basic science of fish swimming behavior and provided data required for the design of fishways. Innovative methods have allowed cultivation of the species in the Yangtze River and, if effective fishways could be incorporated into the design of future hydropower projects on the Amur River, it would contribute to conservation of wild populations of A. schrenckii. The information provided here contributes to the international effort to save this critically endangered species. J. Exp. Zool. 319A:149-155, 2013. © 2013 Wiley Periodicals, Inc.

  9. Induction of meiotic gynogenesis in ship sturgeon Acipenser nudiventris using UV-irradiated heterologous sperm.

    PubMed

    Hassanzadeh Saber, Mohammad; Noveiri, Shahrouz Baradaran; Pourkazemi, Mohammad; Yazdani, Mohammadali; Ghoroghi, Ahmad; Bahmani, Mahmoud; Pourdehghani, Mohammad; Chakmehdouz, Fereidoon; Yarmohammadi, Mahtab; Nowruzfashkhami, Mohammadreza

    2014-05-01

    Diploid gynogenesis was induced in ship sturgeon Acipenser nudiventris using UV-irradiated sperm from Siberian sturgeon Acipenser baerii. The optimal condition for the retention of the second polar body in ship sturgeon was determined to be 10 min after activation/fertilization in experiments. The temperature of cold shock and its duration were 2.5 °C and 30 min, respectively. A total of 30 gynogens of known parentage from experimental treatments were screened using microsatellite DNA analysis, and uniparental transmission in meiogens was confirmed. The results show that heterologous Siberian sturgeon sperm is applicable as UV-irradiated sperm for the induction of gynogenesis in ship sturgeon. This technique may recover the critically endangered sturgeon species that are becoming extinct.

  10. Outbreak of mortality in Russian (Acipenser gueldenstaedtii) and Siberian (Acipenser baerii) sturgeons associated with sturgeon nucleo-cytoplasmatic large DNA virus.

    PubMed

    Ciulli, S; Volpe, E; Sirri, R; Passalacqua, P L; Cesa Bianchi, F; Serratore, P; Mandrioli, L

    2016-08-15

    Diseased outbreaks with high mortality in farmed sturgeon are a limiting factor to the success of this emerging aquaculture sector in Europe. Thorough investigations of outbreaks can determine the aetiological agents, identify important pathological and epidemiological pathways of infections and pave the way for effective control strategies. A thorough investigation of a mortality outbreak in Russian (Acipenser gueldenstaedtii) and Siberian (Acipenser baerii) sturgeons in Italy, demonstrated the primary involvement of a sturgeon nucleo-cytoplasmic large DNA virus (NCLDV). While, the taxonomy classification of this new virus is still uncertain, its involvement in sturgeon mortality outbreaks in Europe is, for the first time, fully investigated and described. Furthermore, the coinfection of bacteria such as motile Aeromonas spp. and Acinetobacter spp. was reported. Genetic characterisation showed the close relationship between the European sturgeon NCLDV with North American sturgeon NCLDVs. Similarly to the latter, the European sturgeon NCLDV persists in survivors. Furthermore, a systemic distribution of the European sturgeon NCLDV was evident in diseased A. baerii and A. gueldenstaedtii and in recovered A. gueldenstaedtii. These epidemiological and pathological findings will help in the identification of effective control strategies for sturgeon NCLDV infection, which afflicts an important and emerging European aquaculture sector.

  11. Isosmotic points and their ecological significance for juvenile Chinese sturgeon Acipenser sinensis.

    PubMed

    Zhao, F; Zhuang, P; Zhang, T; Wang, Y; Hou, J; Liu, J; Zhang, L

    2015-04-01

    Serum osmolality and ion concentrations were measured in juvenile Chinese sturgeon Acipenser sinensis at different salinities to determine the isosmotic point. Isosmotic and isoionic concentrations were calculated from the regressions for serum and ambient osmolality, with Na(+) , Cl(-) and K(+) as salinities 9·19, 8·17, 7·89 and 9·70, respectively. These values were consistent with the salinity of the habitat where juvenile A. sinensis occur in the Yangtze Estuary, suggesting that an isosmotic salinity is an important factor driving their habitat choice.

  12. Characterization of Gulf sturgeon diel and seasonal activity in the Pensacola Bay system, Florida

    NASA Astrophysics Data System (ADS)

    Wrege, Beth Marie

    2009-12-01

    We assess temporal and spatial distribution and diel variability in activity of Gulf of Mexico sturgeon Acipenser oxyrinchus desotoi in the Pensacola Bay system, Florida, using stationary ultrasonic telemetry. Gulf of Mexico sturgeon (n = 54) migrated through the bay system in fall to wintering areas in the Gulf of Mexico and Santa Rosa Sound. In spring, sturgeon migrated back through the bay system to summering habitats in rivers. Gulf of Mexico sturgeon use East Bay and Escambia Bay primarily as migration routes between riverine areas used in spring and summer and the Gulf of Mexico used in winter. North Central Pensacola Bay was not routinely frequented. Gulf of Mexico sturgeon used specific areas within the Pensacola Bay system in summer and winter not previously documented as essential sturgeon habitat. Areas in southeastern Pensacola were used heavily during winter by a portion of the population. Gulf of Mexico sturgeon also exhibited long-term winter residency in Santa Rosa Sound. Interestingly, an area in northeastern Escambia Bay supported Gulf of Mexico sturgeon in summer. This observation was unexpected; however, the identification of Gulf of Mexico sturgeon in this area at this time has important ecological and management implications. Gulf of Mexico sturgeon exhibited a strong diel activity pattern. Gulf of Mexico sturgeon were more active at night than during day in all seasons but summer. The use of prepositioned arrays of acoustic receivers not only provides continuous data within a defined area, but provides insights into nocturnal behavior not previously examined.

  13. Diel activity of Gulf of Mexico sturgeon in a northwest Florida bay

    USGS Publications Warehouse

    Wrege, B.M.; Duncan, M.S.; Isely, J.J.

    2011-01-01

    In this paper, we assess patterns in activity of Gulf of Mexico sturgeon Acipenser oxyrinchus desotoi over a 24-h period in the Pensacola bay system, Florida. Although seasonal migration of sturgeon is well documented, little information is available pertaining to daily variation in activity. We surgically implanted 58 Gulf sturgeon with acoustic transmitters in the Escambia (n=26), Yellow (n=8), Blackwater (n=12) and Choctawhatchee rivers (n=12) in June, July, September and October 2005. Gulf sturgeon location was monitored using an array of 56 fixed-station acoustic receivers. The relationship between frequency of Gulf sturgeon observations recorded on all acoustic receivers and time of day for all seasons combined indicated a strong diel activity pattern. Gulf sturgeon were frequently detected at night in all seasons with the exception of summer. Consecutive hourly observations indicated lateral movement of Gulf sturgeon between independent acoustic receivers on 15% of all observations of individuals. The use of an acoustic receiver array not only provides continuous data within a defined area, but also provides insight into nocturnal behavior of Gulf sturgeon not previously identified. ?? 2011 Blackwell Verlag, Berlin.

  14. Summer habitat use by Gulf sturgeon in the Choctawhatchee River, Florida

    USGS Publications Warehouse

    Hightower, J.E.; Zehfuss, K.P.; Fox, D.A.; Parauka, F.M.

    2002-01-01

    The Gulf sturgeon (Acipenser oxyrinchus desotoi) was listed as a threatened species in 1991 because of declines in abundance throughout the Gulf of Mexico. One recommendation of the recovery plan for Gulf sturgeon was to characterize critical habitats. In this study, radio telemetry was used to determine summer (June-August) distribution and habitat use of Gulf sturgeon in the Choctawhatchee River, Florida-Alabama. Ranging from 74 to 222 cm total length, 63 radio-tagged fish were located 398 times during weekly or biweekly searches in June-August of 1994-1997. A 10-km section of the lower Choctawhatchee River (river km 40-49.9) accounted for 38% of the summer locations of immature fish (less than 1.3 m fork length) and 73% for mature fish. Fish were typically located at sites that were 2-5 m in depth, with water temperatures of 25-28??C and a sand substrate. Spring discharges account for up to one-third of the mainstem river flow in this reach, but water temperatures at fish locations were similar to temperatures at fish locations in all other sections of the river. Efforts to monitor and improve habitat quality should be focussed on this river reach, given that a high percentage of the total Choctawhatchee River population occurs there during summer.

  15. Seasonal migration of Gulf sturgeon in the Suwannee River, Florida

    USGS Publications Warehouse

    Foster, A.M.; Clugston, J.P.

    1997-01-01

    The movements of 67 Gulf sturgeon Acipenser oxyrinchus desotoi equipped with radio transmitters were monitored in the Suwannee River, Florida, from March 1989 through August 1992. The objectives of this study were (1) to determine the seasonal movement patterns and distribution of Gulf sturgeon while in freshwater, (2) to document relationships between water temperature and Gulf sturgeon movement, and (3) to determine whether springs were used as thermal refugia by these fish. Gulf sturgeon were detected entering the river from mid-February through April; they moved upstream at an average speed of 3.5 km/d to areas where they remained until October or November. Gulf sturgeon moved no more than 0,6 river km (on average) upstream or downstream from their established summer area. Gulf sturgeon began leaving the Suwannee River from mid-September through early November and moved downstream at an average speed of 6.2 km/d; all fish returned to the Gulf of Mexico by early December. Water temperatures associated with spring and fall migrations averaged 22.1 ??C (range, 16.0-28.0??C) and 21.3??C (range, 16.9-26.8??C), respectively. Gulf sturgeon were frequently close to springs throughout the warmest period, but none were located within a spring or the thermal plume emanating from a spring.

  16. Research tools to investigate movements, migrations, and life history of sturgeons (Acipenseridae), with an emphasis on marine-oriented populations.

    PubMed

    Nelson, Troy C; Doukakis, Phaedra; Lindley, Steven T; Schreier, Andrea D; Hightower, Joseph E; Hildebrand, Larry R; Whitlock, Rebecca E; Webb, Molly A H

    2013-01-01

    Worldwide, sturgeons (Acipenseridae) are among the most endangered fishes due to habitat degradation, overfishing, and inherent life history characteristics (long life span, late maturation, and infrequent spawning). As most sturgeons are anadromous, a considerable portion of their life history occurs in estuarine and marine environments where they may encounter unique threats (e.g., interception in non-target fisheries). Of the 16 marine-oriented species, 12 are designated as Critically Endangered by the IUCN, and these include species commercially harvested. We review important research tools and techniques (tagging, electronic tagging, genetics, microchemistry, observatory) and discuss the comparative utility of these techniques to investigate movements, migrations, and life-history characteristics of sturgeons. Examples are provided regarding what the applications have revealed regarding movement and migration and how this information can be used for conservation and management. Through studies that include Gulf (Acipenser oxyrinchus desotoi) and Green Sturgeon (A. medirostris), we illustrate what is known about well-studied species and then explore lesser-studied species. A more complete picture of migration is available for North American sturgeon species, while European and Asian species, which are among the most endangered sturgeons, are less understood. We put forth recommendations that encourage the support of stewardship initiatives to build awareness and provide key information for population assessment and monitoring.

  17. Research Tools to Investigate Movements, Migrations, and Life History of Sturgeons (Acipenseridae), with an Emphasis on Marine-Oriented Populations

    PubMed Central

    Nelson, Troy C.; Doukakis, Phaedra; Lindley, Steven T.; Schreier, Andrea D.; Hightower, Joseph E.; Hildebrand, Larry R.; Whitlock, Rebecca E.; Webb, Molly A. H.

    2013-01-01

    Worldwide, sturgeons (Acipenseridae) are among the most endangered fishes due to habitat degradation, overfishing, and inherent life history characteristics (long life span, late maturation, and infrequent spawning). As most sturgeons are anadromous, a considerable portion of their life history occurs in estuarine and marine environments where they may encounter unique threats (e.g., interception in non-target fisheries). Of the 16 marine-oriented species, 12 are designated as Critically Endangered by the IUCN, and these include species commercially harvested. We review important research tools and techniques (tagging, electronic tagging, genetics, microchemistry, observatory) and discuss the comparative utility of these techniques to investigate movements, migrations, and life-history characteristics of sturgeons. Examples are provided regarding what the applications have revealed regarding movement and migration and how this information can be used for conservation and management. Through studies that include Gulf (Acipenser oxyrinchus desotoi) and Green Sturgeon (A. medirostris), we illustrate what is known about well-studied species and then explore lesser-studied species. A more complete picture of migration is available for North American sturgeon species, while European and Asian species, which are among the most endangered sturgeons, are less understood. We put forth recommendations that encourage the support of stewardship initiatives to build awareness and provide key information for population assessment and monitoring. PMID:23990959

  18. Vulnerability of young white sturgeon, Acipenser transmontanus, to predation in the presence of alternative prey

    USGS Publications Warehouse

    Gadomski, D.M.; Parsley, M.J.

    2005-01-01

    We conducted laboratory trials to test the vulnerability of young white sturgeon, Acipenser transmontanus, to predation when an alternative prey was available. In trials with two species of predators, we observed two feeding patterns. When equal numbers of white sturgeon and goldfish, Carassius auratus, were available, prickly sculpins, Cottus asper, ingested more white sturgeon. Conversely, northern pikeminnow, Ptychocheilus oregonensis, ate more juvenile coho salmon, Oncorhynchus kisutch, than white sturgeon in three out of four sets of trials, but ate more white sturgeon in one set of trials. White sturgeon size and the availability of cover did not affect the proportions of prey species ingested. Our results indicate that predation may be affecting survival of white sturgeon larvae and juveniles in the wild and could be one factor limiting recruitment of young-of-the-year white sturgeon in some locations. ?? Springer 2005.

  19. Biological assessment for the shortnose sturgeon, Acipenser brevirostrum Lesueur 1818, the Savannah River Plant

    SciTech Connect

    Muska, C.; Matthews, R.A.

    1983-10-01

    The shortnose sturgeon (Acipenser brevirostrum) is listed as an endangered species in the United States. Prior to 1982, the presence of shortnose sturgeon had not been documented in the middle reaches of the Savannah River. However, shortnose sturgeon larvae were collected in 1982-1983 near the Savannah River Plant (SRP), a US Department of Energy (DOE) facility, as part of the SRP aquatic ecology program. This biological assessment was prepared to evaluate the potential impacts of present and proposed SRP operations on the shortnose sturgeon. This assessment is based on existing information on the life history and habitat preferences of the shortnose sturgeon, a description of the Savannah River Plant including plant operations which may potentially impact the shortnose sturgeon and consultations with local experts. From this information, it is concluded that the existing and proposed operations (specifically L-Reactor operation) of the Savannah River Plant will not affect the continued existence of the shortnose sturgeon the Savannah River.

  20. Overview of biology and aquaculture of Amur sturgeon (Acipenser schrenckii) in China

    USGS Publications Warehouse

    Zhuang, P.; Kynard, B.; Zhang, L.; Zhang, T.; Zhang, Z.; Li, D.

    2002-01-01

    Amur sturgeon, Acipenser schrenckii is a large riverine species (max. 3 m length and 190 kg weight) native to the Amur River. In the middle Amur River, males first spawn at 7-8 years of age and females at 9-10 years. Due to overfishing and habitat alteration, the abundance of wild stocks has rapidly declined in recent years. Using wild adults, artificial spawning began in the 1950s in China, and since the early 1990s Amur sturgeon has become the most popular sturgeon for aquaculture. The species is adaptive to many conditions of artificial culture, including traditional Chinese fish culture ponds, lakes, reservoirs, and cages. It will grow well on many types of food, and 1-year-old fish reared on commercial diets weigh 900-1200 g. Based on the examination of females reared for broodstock, first full sexual maturity is expected at 5-6 years of age.

  1. [Impacts of ultraviolet irradiation on the sperm motility and longevity of Acipenser baerii].

    PubMed

    Zhang, Tao; Yan, Shi-wei; Zhang, Long-zhen; Zhuang, Ping; Tian, Mei-ping; Yan, Wen-gang; Jiang, Qi; Yao, Zhi-feng

    2011-08-01

    This paper studied the impacts of different dose ultraviolet irradiation (254 nm, UVC) on the sperm motility and longevity of Acipenser baerii. Ultraviolet irradiation had significant impacts on the sperm motility, its fast motion time, and longevity. With the increasing dose of ultraviolet irradiation, the sperm motility decreased rapidly first, increased rapidly then, and decreased rapidly again. The sperm fast motion time had the similar variation trend as the sperm motility, but the sperm longevity kept decreasing with increasing dose of ultraviolet irradiation. When the ultraviolet irradiation dose increased to 288 mJ x cm(-2), the sperm fast motion disappeared; when the ultraviolet irradiation dose increased up to 324 mJ x cm(-2), the sperm had no motility and died. According to the "Hertwig effect", the optimum ultraviolet irradiation dose for inactivating A. baerii sperm was 216 mJ x cm(-2).

  2. Life history and status of shortnose sturgeon (Acipenser brevirostrum) in the Potomac River

    USGS Publications Warehouse

    Kieffer, Micah

    2009-01-01

    We collected the first life history information on shortnose sturgeon (Acipenser brevirostrum) in any of the rivers to Chesapeake Bay, the geographic center of the species range. In the Potomac River, two telemetry-tagged adult females used 124 km of river: a saltwater/freshwater reach at river km (rkm) 63-141 was the foraging-wintering concentration area, and one female migrated to spawn at rkm 187 in Washington, DC. The spawning migration explained the life history context of an adult captured 122 years ago in Washington, DC, supporting the idea that a natal population once lived in the river. Repeated homing migrations to foraging and wintering areas suggested the adults were residents, not transient coastal migrants. All habitats that adults need to complete life history are present in the river. The Potomac River shortnose sturgeon offers a rare opportunity to learn about the natural rebuilding of a sturgeon population.

  3. Life history and status of shortnose sturgeon (Acipenser brevirostrum) in the potomac river

    USGS Publications Warehouse

    Kynard, B.; Breece, M.; Atcheson, M.; Kieffer, M.; Mangold, M.

    2009-01-01

    We collected the first life history information on shortnose sturgeon (Acipenser brevirostrum) in any of the rivers to Chesapeake Bay, the geographic center of the species range. In the Potomac River, two telemetry-tagged adult females used 124 km of river: A saltwater/freshwater reach at river km (rkm) 63-141 was the foraging-wintering concentration area, and one female migrated to spawn at rkm 187 in Washington, DC. The spawning migration explained the life history context of an adult captured 122 years ago in Washington, DC, supporting the idea that a natal population once lived in the river. Repeated homing migrations to foraging and wintering areas suggested the adults were residents, not transient coastal migrants. All habitats that adults need to complete life history are present in the river. The Potomac River shortnose sturgeon offers a rare opportunity to learn about the natural rebuilding of a sturgeon population. ?? 2009 Blackwell Verlag, Berlin.

  4. Malformations of the endangered Chinese sturgeon, Acipenser sinensis, and its causal agent

    PubMed Central

    Hu, Jianying; Zhang, Zhaobin; Wei, Qiwei; Zhen, Huajun; Zhao, Yanbin; Peng, Hui; Wan, Yi; Giesy, John P.; Li, Luoxin; Zhang, Bo

    2009-01-01

    The anadromous Chinese sturgeon (Acipenser sinensis) is endangered and listed among the first class of protected animals in China. The possible causes for the decline of this species are the effects of synthetic chemicals, and loss of critical habitat. Chinese sturgeon in the Yangtze River have accumulated triphenyltin (TPT) to 31–128 ng/g wet weigh (ww) in liver, which is greater than the concentrations of tributyltin (<1.0 ng/g ww). Maternal transfer of TPT has resulted in concentrations of 25.5 ± 13.0 ng/g ww in eggs of wild Chinese sturgeon, which poses a significant risk to the larvae naturally fertilized or hatched in the Yangtze River. The incidence of deformities in fry was 7.5%, with 1.2% of individuals exhibiting ocular abnormal development, and 6.3% exhibited skeletal/morphological deformations. The incidences of both ocular and skeletal/morphological deformations were directly proportional to the TPT concentration in the eggs of both the Chinese sturgeon and the Siberian sturgeon (Acipenser baerii) in controlled laboratory studies. The rates of deformities in the controlled studies were consistent with the rates caused at the similar concentrations in eggs collected from the field. Thus, TPT is the causal agent to induce the malformation of larvae of Chinese sturgeon. The incidence of deformed larvae of Chinese sturgeon is an indicator of overall population-level effects of TPT on Chinese sturgeon, because TPT at environmentally relevant concentrations can result in significantly decrease both quality and quantity of eggs and spawning frequency of fish. PMID:19470453

  5. Salinity effects on Atlantic sturgeon growth and osmoregulation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus Mitchill, 1815) is an anadromous sturgeon species, yet little is known with regard to its osmoregulatory ability and habitat use at early life stages. In order to examine whether salinity poses a physiological challenge to juvenile Atlantic stur...

  6. 75 FR 69049 - Endangered and Threatened Wildlife and Plants; Proposed Listings for Two Distinct Population...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-10

    ... hearings--one in Wilmington, NC and one in Atlanta, GA. The purpose of these hearings is to accept comments... Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) as endangered under the Endangered Species Act (ESA) of 1973, as amended. DATES: The hearings will be held on December 6, 2010, from 6 to 9 p.m. in...

  7. 77 FR 5879 - Endangered and Threatened Wildlife and Plants; Threatened and Endangered Status for Distinct...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-06

    ...We, NMFS, are issuing a final determination to list the Gulf of Maine (GOM) Distinct Population Segment (DPS) of Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) as a threatened species under the Endangered Species Act (ESA), and the New York Bight (NYB) and Chesapeake Bay (CB) DPSs of Atlantic sturgeon as endangered species under the ESA. We have proposed protective regulations for the GOM......

  8. Activation of the Albino Sterlet Acipenser ruthenus Eggs by UV-Irradiated Bester Hybrid Spermatozoa to Provide Gynogenetic Progeny.

    PubMed

    Fopp-Bayat, D; Ocalewicz, K

    2015-08-01

    Meiotic gynogenesis was induced in the albino form of sterlet Acipenser ruthenus by activation of eggs with UV-irradiated bester (Huso huso x Acipenser ruthenus) spermatozoa followed by inhibition of the second meiotic division performed by a heat shock. Obtained putative gynogenetic progeny were all albinos. The genetic verification based on three microsatellite DNA markers confirmed the only maternal inheritance of the progeny from the gynogenetic experimental groups. Cytogenetic analysis proved the gynogenetic sterlets were diploids. Application of the albino phenotype together with the molecular and the cytogenetic diagnostic approaches enabled to evaluate the efficiency of the spermatozoa irradiation and application of the heat shock to restore diploid state in the gynogenetic zygotes.

  9. Digestive enzyme activities are higher in the shortfin mako shark, Isurus oxyrinchus, than in ectothermic sharks as a result of visceral endothermy.

    PubMed

    Newton, Kyle C; Wraith, James; Dickson, Kathryn A

    2015-08-01

    Lamnid sharks are regionally endothermic fishes that maintain visceral temperatures elevated above the ambient water temperature. Visceral endothermy is thought to increase rates of digestion and food processing and allow thermal niche expansion. We tested the hypothesis that, at in vivo temperatures, the endothermic shortfin mako shark, Isurus oxyrinchus, has higher specific activities of three digestive enzymes-gastric pepsin and pancreatic trypsin and lipase-than the thresher shark, Alopias vulpinus, and the blue shark, Prionace glauca, neither of which can maintain elevated visceral temperatures. Homogenized stomach or pancreas tissue obtained from sharks collected by pelagic longline was incubated at both 15 and 25 °C, at saturating substrate concentrations, to quantify tissue enzymatic activity. The mako had significantly higher enzyme activities at 25 °C than did the thresher and blue sharks at 15 °C. This difference was not a simple temperature effect, because at 25 °C the mako had higher trypsin activity than the blue shark and higher activities for all enzymes than the thresher shark. We also hypothesized that the thermal coefficient, or Q 10 value, would be higher for the mako shark than for the thresher and blue sharks because of its more stable visceral temperature. However, the mako and thresher sharks had similar Q 10 values for all enzymes, perhaps because of their closer phylogenetic relationship. The higher in vivo digestive enzyme activities in the mako shark should result in higher rates of food processing and may represent a selective advantage of regional visceral endothermy.

  10. Effects of incubation substrates on hatch timing and success of White Sturgeon (Acipenser transmontanus) embryos

    USGS Publications Warehouse

    Parsley, Michael J.; Kofoot, Eric

    2013-01-01

    The Kootenai River white sturgeon (Acipenser transmontanus) was listed as endangered under the Endangered Species Act in 1994 because several decades of failed spawning had put the population at risk of extinction. Natural spawning is known to occur at several locations in the Kootenai River, Idaho, but there is little natural recruitment. Microhabitat where embryo incubation occurs is known to be an important factor in white sturgeon reproductive success. This study was conducted to address questions regarding the suitability of different substrates as egg attachment and incubation sites for these fish. A comparative laboratory study using six types of incubation substrates—clean river rocks, periphyton- and algae-covered rocks, waterlogged wood, sand, riparian vegetation, and clean glass plates—tested the hypothesis that survival to hatch of white sturgeon eggs differs among incubation substrates. The results showed that sand was unsuitable as an incubation substrate, as the adhesive embryos were easily dislodged. Periphyton- and algae-covered rocks had the lowest hatch success, and all other substrates had similar hatch success.

  11. Lake Sturgeon, Acipenser fulvescens, movements in Rainy Lake, Minnesota and Ontario

    USGS Publications Warehouse

    Adams, W.E.; Kallemeyn, L.W.; Willis, D.W.

    2006-01-01

    Rainy Lake, Minnesota-Ontario, contains a native population of Lake Sturgeon (Acipenser fulvescens) that has gone largely unstudied. The objective of this descriptive study was to summarize generalized Lake Sturgeon movement patterns through the use of biotelemetry. Telemetry data reinforced the high utilization of the Squirrel Falls geographic location by Lake Sturgeon, with 37% of the re-locations occurring in that area. Other spring aggregations occurred in areas associated with Kettle Falls, the Pipestone River, and the Rat River, which could indicate spawning activity. Movement of Lake Sturgeon between the Seine River and the South Arm of Rainy Lake indicates the likelihood of one integrated population on the east end of the South Arm. The lack of re-locations in the Seine River during the months of September and October may have been due to Lake Sturgeon moving into deeper water areas of the Seine River and out of the range of radio telemetry gear or simply moving back into the South Arm. Due to the movements between Minnesota and Ontario, coordination of management efforts among provincial, state, and federal agencies will be important.

  12. Changes in growth and osmoregulation during acclimation to saltwater in juvenile Amur sturgeon Acipenser schrenckii

    NASA Astrophysics Data System (ADS)

    Zhao, Feng; Zhuang, Ping; Zhang, Longzhen; Hou, Junli

    2010-05-01

    We evaluated the ability of juvenile Amur sturgeon ( Acipenser schrenckii) to osmoregulate and grow in saltwater. Hatchery-reared juveniles (mean weight 106.8 g, 5-month old) were transferred from freshwater to 10, 20, and 25 salinity saltwater over a period of 20 d. We measured the growth, serum osmolality, ion concentrations, and Na+/K+-ATPase activity. In addition, we prepared samples of gill tissue to quantify morphological changes in gill ultrastructure. Rearing in up to 25 saltwater for 30 d had no significant effect on growth. Similarly, serum osmolality and ion concentrations were similar to levels reported in other teleosts following acclimation to saltwater. Serum osmolality and Na+, Cl- concentrations increased significantly with the initial increase in salinity. Afterwards, levels tended to stabilize and then decrease. Serum K+ levels did not change during acclimation to saltwater. Gill Na+/K+-ATPase activity increased initially as salinity was increased. However, the activity later decreased and, finally stabilized at 3.7±0.1 μmol Pi/mg·prot·h in 25 saltwater (1.6 times higher than the level in those in freshwater). In fish that were held only in freshwater, the chloride cells were located in the interlamellar regions of the filament and at the base of the lamella. Following acclimation to 25 saltwater for 30 d, the number and size of chloride cells increased significantly. Our results suggest that juvenile Amur sturgeon is able to tolerate, and grow in, relatively high concentrations of saltwater.

  13. Movement and habitat use of green sturgeon Acipenser medirostris in the Rogue River, Oregon, USA

    USGS Publications Warehouse

    Erickson, D.L.; North, J.A.; Hightower, J.E.; Weber, J.; Lauck, L.

    2002-01-01

    Green sturgeon (Acipenser medirostris) movement patterns and habitat use within the Rogue River, Oregon were evaluated using radio telemetry. Nineteen specimens ranging from 154 to 225 cm total length were caught by gill netting and tagged with radio transmitters during May-July 2000. One tagged green sturgeon was verified as a female near spawning condition. Individual green sturgeons spent more than 6 months in fresh water and traveled as far as river kilometer (rkm) 39.5. Green sturgeon preferred specific holding sites within the Rogue River during summer and autumn months. These sites were typically deep (> 5 m) low-gradient reaches or off-channel coves. Home ranges within holding sites were restricted. All tagged individuals emigrated from the system to the sea during the autumn and winter, when water temperatures dropped below 10??C and flows increased. This species is extremely vulnerable to habitat alterations and overfishing because it spawns in only a few North American rivers and individuals reside within extremely small areas for extended periods of time.

  14. Genetic and demographic implications of aquaculture in white sturgeon (Acipenser transmontanus)conservation

    SciTech Connect

    Jager, Yetta

    2005-01-01

    This study uses a genetic individual-based model of white sturgeon (Acipenser transmontanus) populations in a river to examine the genetic and demographic trade-offs associated with operating a conservation hatchery. Simulation experiments evaluated three management practices: (i) setting quotas to equalize family contributions in an effort to prevent genetic swamping, (ii) an adaptive management scheme that interrupts stocking when introgression exceeds a specified threshold, and (iii) alternative broodstock selection strategies that influence domestication. The first set of simulations, designed to evaluate equalizing the genetic contribution of families, did not show the genetic benefits expected. The second set of simulations showed that simulated adaptive management was not successful in controlling introgression over the long term, especially with uncertain feedback. The third set of simulations compared the effects of three alternative broodstock selection strategies on domestication for hypothetical traits controlling early density-dependent survival. Simulated aquaculture selected for a density-tolerant phenotype when broodstock were taken from a genetically connected population. Using broodstock from an isolated population (i.e., above an upstream barrier or in a different watershed) was more effective at preventing domestication than using wild broodstock from a connected population.

  15. Ultrastructural study on the fertilisation process in sturgeon (Acipenser), function of acrosome and prevention of polyspermy.

    PubMed

    Psenicka, Martin; Rodina, Marek; Linhart, Otomar

    2010-01-01

    Sturgeon gametes differ from other fish in that their spermatozoa possess acrosome with finger-like posterolateral projections, which undergo exocytosis and filament formation, whereas eggs possess numerous micropyles. The fertilisation process in Acipenser baerii was investigated by fluorescence and electron microscopy. A suitable activation solution containing 2.5 mM CaCl(2), 15 mM Tris, pH 10 was found for detailed description of acrosomal reaction. The acrosome reaction includes the formation of a spear-like fertilisation filament coming from three endonuclear canals and implantation fossa through the acrosomes. It can accelerate the process of polyspermy prevention. Another unique feature of the acrosome was an anchor-like opening of the posterolateral projections. Mature eggs of A. baerii possessed 2-10 micropyles in the animal pole region. The eggs consisted of three principal layers and an outermost jelly coat blocking micropyle, and a layer of cortical granules in unfertilised eggs. With the exposure to freshwater, the jelly like layer separated from the egg surface, whereas the cortical granules swelled. No change between the layers of fertilised and unfertilised eggs, apart from the generation of an increasing perivitelline space by dissolution of the cortical granules, had been observed after the fusion of spermatozoon with an egg. A fertilisation cone blocked a fusion of other spermatozoa with cytoplasmatic projection in the fertilised micropyle.

  16. Unscreened Water-Diversion Pipes Pose an Entrainment Risk to the Threatened Green Sturgeon, Acipenser medirostris

    PubMed Central

    Mussen, Timothy D.; Cocherell, Dennis; Poletto, Jamilynn B.; Reardon, Jon S.; Hockett, Zachary; Ercan, Ali; Bandeh, Hossein; Kavvas, M. Levent; Cech, Joseph J.; Fangue, Nann A.

    2014-01-01

    Over 3,300 unscreened agricultural water diversion pipes line the levees and riverbanks of the Sacramento River (California) watershed, where the threatened Southern Distinct Population Segment of green sturgeon, Acipenser medirostris, spawn. The number of sturgeon drawn into (entrained) and killed by these pipes is greatly unknown. We examined avoidance behaviors and entrainment susceptibility of juvenile green sturgeon (35±0.6 cm mean fork length) to entrainment in a large (>500-kl) outdoor flume with a 0.46-m-diameter water-diversion pipe. Fish entrainment was generally high (range: 26–61%), likely due to a lack of avoidance behavior prior to entering inescapable inflow conditions. We estimated that up to 52% of green sturgeon could be entrained after passing within 1.5 m of an active water-diversion pipe three times. These data suggest that green sturgeon are vulnerable to unscreened water-diversion pipes, and that additional research is needed to determine the potential impacts of entrainment mortality on declining sturgeon populations. Data under various hydraulic conditions also suggest that entrainment-related mortality could be decreased by extracting water at lower diversion rates over longer periods of time, balancing agricultural needs with green sturgeon conservation. PMID:24454967

  17. Microsatellite analyses across three diverse vertebrate transcriptomes (Acipenser fulvescens, Ambystoma tigrinum, and Dipodomys spectabilis).

    PubMed

    Doyle, Jacqueline M; Siegmund, Gregor; Ruhl, Joseph D; Eo, Soo Hyung; Hale, Matthew C; Marra, Nicholas J; Waser, Peter M; Dewoody, J Andrew

    2013-07-01

    Historically, many population genetics studies have utilized microsatellite markers sampled at random from the genome and presumed to be selectively neutral. Recent studies, however, have shown that microsatellites can occur in transcribed regions, where they are more likely to be under selection. In this study, we mined microsatellites from transcriptomes generated by 454-pyrosequencing for three vertebrate species: lake sturgeon (Acipenser fulvescens), tiger salamander (Ambystoma tigrinum), and kangaroo rat (Dipodomys spectabilis). We evaluated (i) the occurrence of microsatellites across species; (ii) whether particular gene ontology terms were over-represented in genes that contained microsatellites; (iii) whether repeat motifs were located in untranslated regions or coding sequences of genes; and (iv) in silico polymorphism. Microsatellites were less common in tiger salamanders than in either lake sturgeon or kangaroo rats. Across libraries, trinucleotides were found more frequently than any other motif type, presumably because they do not cause frameshift mutations. By evaluating variation across reads assembled to a given contig, we were able to identify repeat motifs likely to be polymorphic. Our study represents one of the first comparative data sets on the distribution of vertebrate microsatellites within expressed genes. Our results reinforce the idea that microsatellites do not always occur in noncoding DNA, but commonly occur in expressed genes.

  18. Differential expression of fertility genes boule and dazl in Chinese sturgeon (Acipenser sinensis), a basal fish.

    PubMed

    Ye, Huan; Li, Chuang-Ju; Yue, Hua-Mei; Yang, Xiao-Ge; Wei, Qi-Wei

    2015-05-01

    The gene family DAZ (deleted in Azoospermia), including boule, dazl and DAZ, performs highly conserved functions in germ cell development and fertility across animal phyla. Differential expression patterns have been demonstrated for the family members in invertebrates and vertebrates including fish. Here, we report the identification of boule and dazl and their expression at both RNA and protein levels in developing and mature gonads of Chinese sturgeon (Acipenser sinensis). Firstly, the isolation of the boule and dazl genes in Chinese sturgeon and the observation of the two genes in coelacanth suggest that dazl originated after the divergence of bony fish from cartilaginous fish but before the emergence of the Actinistia. Quantitative real-time PCR and western blot analyses reveal that boule and dazl RNA and proteins are restricted to the testis and ovary. In situ hybridization and fluorescent immunohistochemistry show that the bisexual mitotic and meiotic germ cell expression of dazl RNA and protein is conserved in vertebrates, while Chinese sturgeon boule RNA and protein exhibit mitotic and meiotic expression in the testis, and also likely display mitotic and meiotic expression in female. Moreover, we directly demonstrate for the first time that sturgeon Balbiani body/mitochondrial cloud disperses in the cytoplasm of early developing oocytes and co-localizes with Dazl to some extent. Finally, urbilaterian boule may also have an ancestral function in oogenesis. Taken together, these results provide useful information on the evolution of DAZ family genes, expression patterns and functions in animal reproduction.

  19. Disturbances in the ploidy level in the gynogenetic sterlet Acipenser ruthenus.

    PubMed

    Fopp-Bayat, D; Ocalewicz, K; Kucinski, M; Jankun, M; Laczynska, B

    2017-02-06

    Artificial mitotic gynogenesis, a chromosome set manipulation, is applied to provide the homozygous progeny with only maternal inheritance. Here, gynogenetic development was induced in the sterlet Acipenser ruthenus L. (Acipenseridae) by activation of the eggs originating from albino females with the UV-irradiated spermatozoa from wild-coloured males, followed by the heat shock applied to suppress the first mitotic division in the haploid zygotes. All experimentally obtained gynogenetic offspring possessed recessive albino coloration. Moreover, the genetic verification, based on three microsatellite DNA markers, confirmed the only maternal inheritance in the albino progeny. Cytogenetic screening enabled identification of the aneuploids, haploids, diploids, triploids, tetraploids and mosaic individuals among the gynogenetic larvae that hatched from the eggs subjected to the heat shock. Furthermore, 40% of the larvae from the haploid variants of the research that were not exposed to the temperature shock showed the diploid chromosome number. A variation of the ploidy level observed in the gynogenetic sterlets may be the consequence of the spontaneous polyploidisation that occurred in the haploid zygotes. Moreover, observation during embryogenesis showed varied stages of eggs development and the asynchronous cell cleavages that may have resulted in the chromosomal disturbances observed in the gynogenetic sterlets here.

  20. Accelerometer-derived activity correlates with volitional swimming speed in lake sturgeon (Acipenser fulvescens)

    USGS Publications Warehouse

    Thiem, J.D.; Dawson, J.W.; Gleiss, A.C.; Martins, E.G.; Haro, Alexander J.; Castro-Santos, Theodore R.; Danylchuk, A.J.; Wilson, R.P.; Cooke, S.J.

    2015-01-01

    Quantifying fine-scale locomotor behaviours associated with different activities is challenging for free-swimming fish.Biologging and biotelemetry tools can help address this problem. An open channel flume was used to generate volitionalswimming speed (Us) estimates of cultured lake sturgeon (Acipenser fulvescens Rafinesque, 1817) and these were paired withsimultaneously recorded accelerometer-derived metrics of activity obtained from three types of data-storage tags. This studyexamined whether a predictive relationship could be established between four different activity metrics (tail-beat frequency(TBF), tail-beat acceleration amplitude (TBAA), overall dynamic body acceleration (ODBA), and vectorial dynamic body acceleration(VeDBA)) and the swimming speed of A. fulvescens. Volitional Us of sturgeon ranged from 0.48 to 2.70 m·s−1 (0.51–3.18 bodylengths (BL) · s−1). Swimming speed increased linearly with all accelerometer-derived metrics, and when all tag types werecombined, Us increased 0.46 BL·s−1 for every 1 Hz increase in TBF, and 0.94, 0.61, and 0.94 BL·s−1 for every 1g increase in TBAA,ODBA, and VeDBA, respectively. Predictive relationships varied among tag types and tag-specific parameter estimates of Us arepresented for all metrics. This use of acceleration data-storage tags demonstrated their applicability for the field quantificationof sturgeon swimming speed.

  1. Genome duplication events and functional reduction of ploidy levels in sturgeon (Acipenser, Huso and Scaphirhynchus).

    PubMed Central

    Ludwig, A; Belfiore, N M; Pitra, C; Svirsky, V; Jenneckens, I

    2001-01-01

    Sturgeon (order Acipenserformes) provide an ideal taxonomic context for examination of genome duplication events. Multiple levels of ploidy exist among these fish. In a novel microsatellite approach, data from 962 fish from 20 sturgeon species were used for analysis of ploidy in sturgeon. Allele numbers in a sample of individuals were assessed at six microsatellite loci. Species with approximately 120 chromosomes are classified as functional diploid species, species with approximately 250 chromosomes as functional tetraploid species, and with approximately 500 chromosomes as functional octaploids. A molecular phylogeny of the sturgeon was determined on the basis of sequences of the entire mitochondrial cytochrome b gene. By mapping the estimated levels of ploidy on this proposed phylogeny we demonstrate that (I) polyploidization events independently occurred in the acipenseriform radiation; (II) the process of functional genome reduction is nearly finished in species with approximately 120 chromosomes and more active in species with approximately 250 chromosomes and approximately 500 chromosomes; and (III) species with approximately 250 and approximately 500 chromosomes arose more recently than those with approximately 120 chromosomes. These results suggest that gene silencing, chromosomal rearrangements, and transposition events played an important role in the acipenseriform genome formation. Furthermore, this phylogeny is broadly consistent with previous hypotheses but reveals a highly supported oceanic (Atlantic-Pacific) subdivision within the Acipenser/Huso complex. PMID:11454768

  2. Cryopreservation of Persian sturgeon (Acipenser persicus) embryos by DMSO-based vitrificant solutions.

    PubMed

    Keivanloo, Saeide; Sudagar, Mohammad

    2016-03-15

    Vitrification could provide a promising tool for the cryopreservation of fish embryos. To achieve successful cryopreservation, several parameters should be taken into account in the design of a vitrification protocol. In the present study, some relevant factors were investigated (choice of a proper vitrificant solutions and temperature for thawing) using neurulation-stage embryos. Six DMSO-based vitrificant solutions (V1-V6) were tested using a 6-step incorporation protocol. DMSO-based vitrificant solutions contained DMSO + permeable cryoprotectants + nonpermeable cryoprotectants. Embryos were immersed in vitrificant solutions for 7 minutes and directly plunged into liquid nitrogen. After vitrification (-196 °C for 10 minutes), the thawing was performed in a water bath at 0 or 20 °C and then embryos incubated until hatched. Our results demonstrated that some embryos vitrified in 5 of 6 vitrification solutions survived and hatched out, but none survived after vitrification in V2. The highest survival rate (45.45%) was observed in samples frozen with the best vitrificant solution (V6) and thawing combination (20 °C). These results establish that cryopreservation of Persian sturgeon (Acipenser persicus) embryos by DMSO-based vitrificant solutions is possible.

  3. EST dataset of pituitary and identification of somatolactin and novel genes in Chinese sturgeon, Acipenser sinensis.

    PubMed

    Cao, Hong; Leng, Xiaoqian; Li, Chuangju; Wei, Qiwei; Gui, Jianfang; Cheng, Hanhua; Zhou, Rongjia

    2012-04-01

    Chinese sturgeon (Acipenser sinensis) is a rare and endangered species and also an important resource for the sturgeon aquaculture industry, however, a few genes have been identified in this species. We report here construction of a pituitary cDNA library from a 24 years old female Chinese sturgeon just after its spawning, and obtained 2,025 ESTs from the library. 885 unique sequences were identified, which were categorized into 12 functional groups. More than half of the unique sequences (57%) do not match with annotated sequences in the public databases. Three of these novel genes were further identified. Notably, a full-length of cDNA (1,143 bp) encoding somatolactin of 232 amino acids was identified. Phylogenetic analysis showed 97% amino acid identity with White sturgeon somatolactin. RT-PCR analysis indicated that the somatolactin mRNA was only detected in pituitary. Pituitary-specific expression of the somatolactin suggested that the protein may play important physiological functions in pituitary-endocrine system of the Chinese sturgeon.

  4. Effects of Columbia River water on early life-stages of white sturgeon (Acipenser transmontanus).

    PubMed

    Tompsett, Amber R; Vardy, David W; Higley, Eric; Doering, Jon A; Allan, Marcie; Liber, Karsten; Giesy, John P; Hecker, Markus

    2014-03-01

    The white sturgeon (Acipenser transmontanus) population that resides in the Columbia River in British Columbia (BC), Canada, has suffered recruitment failures for more than three decades. During the summers of 2008 and 2009, studies were performed to determine whether exposure to water downstream of a metal smelter in Trail, BC affected survival or growth of early life-stages of white sturgeon through 60+ days post-fertilization (dpf). In both years, there were no significant differences in survival of fish that were exposed to water from downstream compared to water from upstream of the smelter. At 20-21dpf, average mortality was 2.4 percent and 12 percent in upstream water for 2008 and 2009, respectively, which was similar to the average mortality of 3.8 percent and 7.2 percent in downstream water for 2008 and 2009, respectively. Relatively great mortality after 20-21dpf complicated analysis of the subchronic exposure, but use of a survival analysis indicated that the average fish died at 25-29dpf, regardless of whether the water to which they were exposed came from upstream or downstream of the smelter. In addition, measured concentrations of metals in river water were less than the threshold for adverse effects on early life stages of white sturgeon. Based upon these analyses, it is not likely that current concentrations of metals in the Columbia River in southern BC are adversely affecting survival of early life stages of white sturgeon larvae.

  5. Lethal and sublethal toxicity of didecyldimethylammonium chloride in early life stages of white sturgeon, Acipenser transmontanus.

    PubMed

    Teh, Swee Joo; Wong, Cecilia; Furtula, Vesna; Teh, Foo-Ching

    2003-09-01

    This study was conducted to describe the acute lethality and latent toxicity of didecyldimethylammonium chloride (DDAC) on early life stages of white sturgeon (Acipenser transmontanus). Fish responses to 0, 10, 50, 100, 250, 500 microg/L concentrations of DDAC were determined using a 96-h standard static renewal method for acute toxicity testing, with three replicates per concentration. Twenty fish per replicate were tested for 3, 11, and 42-d-old larvae, and 7 fish per replicate were tested for 78-d-old juveniles. Following exposure, survival and growth were evaluated in exposed fish raised in clean water for 2 weeks. The 96-h median lethal concentration (LC50) values for DDAC were 10.0 to 50.0, 58.5, and 99.7 microg/L for 3, 11, and 42-d-old larvae and 100 to 250 microg/L for 78-d-old juveniles. Significant decreases in larval growth and survival were noted at all tested concentrations and in all sturgeon age groups. Results of this study reveal age- and concentration-dependent responses to DDAC. Among the age groups tested, the 3-d-old larvae were the most sensitive group. Results also revealed that 96-h lethality testing alone is not adequate for determining the toxicity of DDAC to white sturgeon.

  6. Pericardial and pericardioperitoneal canal relationships to cardiac function in the white sturgeon (Acipenser transmontanus).

    PubMed

    Gregory, Joshua A; Graham, Jeffrey B; Cech, Joseph J; Dalton, Nancy; Michaels, Jim; Chin Lai, N

    2004-06-01

    Sturgeons are primitive bony fishes and their hearts have structural features found in other primitive fishes. Sturgeons have a pericardioperitoneal canal (PPC), a one-way conduit into the peritoneum. A PPC also occurs in elasmobranchs (sharks and rays) and studies with that group demonstrate that pericardial pressure and pericardial fluid loss via the PPC affect stroke volume. A study of white sturgeon (Acipenser transmontanus) heart function was conducted to test for a comparable PPC and pericardial effects. White sturgeon-elasmobranch heart-function similarities include biphasic ventricular filling, a comparable operational pericardial pressure (-0.03 kPa), and a strongly negative pressure (-0.2 to -0.6 kPa) with complete pericardial fluid withdrawal. Differences include the white sturgeon's relatively smaller atrium and ventricle but a larger conus arteriosus. Although white sturgeon heart size is also smaller, its pericardial volume is disproportionately less (2.4 to 2.7 vs. 3.5 to 5.4 ml kg(-1) in elasmobranchs), meaning it has less scope for increasing stroke volume upon PPC fluid release. These differences may reflect the phylogenetic progression from the less complex operation of the elasmobranch heart, which lacks sympathetic innervation and has a mechanically mediated (PPC) stroke volume, to the condition in the more derived bony fishes which have sympathetic and parasympathetic regulation of both stroke volume and heart rate.

  7. Fatty acid composition and volatile compounds of caviar from farmed white sturgeon (Acipenser transmontanus).

    PubMed

    Caprino, Fabio; Moretti, Vittorio Maria; Bellagamba, Federica; Turchini, Giovanni Mario; Busetto, Maria Letizia; Giani, Ivan; Paleari, Maria Antonietta; Pazzaglia, Mario

    2008-06-09

    The present study was conducted to characterize caviar obtained from farmed white sturgeons (Acipenser transmontanus) subjected to different dietary treatments. Twenty caviar samples from fish fed two experimental diets containing different dietary lipid sources have been analysed for chemical composition, fatty acids and flavour volatile compounds. Fatty acid make up of caviar was only minimally influenced by dietary fatty acid composition. Irrespective of dietary treatments, palmitic acid (16:0) and oleic acid (OA, 18:1 n-9) were the most abundant fatty acid followed by docosahexaenoic acid (DHA, 22:6 n-3) and eicopentaenoic (EPA, 20:5 n-3). Thirty-three volatile compounds were isolated using simultaneous distillation-extraction (SDE) and identified by GC-MS. The largest group of volatiles were represented by aldehydes with 20 compounds, representing the 60% of the total volatiles. n-Alkanals, 2-alkenals and 2,4-alkadienals are largely the main responsible for a wide range of flavours in caviar from farmed white surgeon.

  8. Adverse health effects and histological changes in white sturgeon (Acipenser transmontanus) exposed to dietary selenomethionine.

    PubMed

    Zee, Jenna; Patterson, Sarah; Gagnon, Danielle; Hecker, Markus

    2016-07-01

    It has been shown that selenium (Se) released to the aquatic environment can have devastating effects on local wildlife. White sturgeon (Acipenser transmontanus) have a life history particularly susceptible to contaminants, and their protection is of interest as they are culturally and economically important, and many populations are classified as endangered. During the present 72-d dietary study, multiple signs of decreased health and Se lethality were observed. Juvenile white sturgeon were given diets containing 1.4 μg, 5.6 μg, 22.4 μg, or 104.4 μg selenomethionine/g food (dry mass). Selenium accumulated in muscle and liver tissue in a dose-dependent manner. Edema causing exophthalmos developed within 15 d and 23 d, and lethal effects occurred in 54% and 22% of fish in the high- and medium-dose groups, respectively. Growth and hepatosomatic index were significantly lower in the high-dose group, which also had a high incidence of food avoidance. Histology of the liver revealed a dose-dependent increase in melanomacrophage aggregates and decrease of energy stores, which indicated toxicity. These results indicate that white sturgeon are susceptible to the effects of Se accumulation over relatively short time periods. This stresses the need for continued sturgeon research and studies looking into the environmental fate and regulation of released Se. Environ Toxicol Chem 2016;35:1741-1750. © 2015 SETAC.

  9. Reduction of vitellogenin synthesis by an aryl hydrocarbon receptor agonist in the white sturgeon (Acipenser transmontamus).

    PubMed

    Palumbo, Amanda J; Denison, Michael S; Doroshov, Serge I; Tjeerdema, Ronald S

    2009-08-01

    Migrating white sturgeon (Acipenser transmontamus) may be subject to agricultural, municipal, and industrial wastewater effluents that likely contain different classes of endocrine-disrupting contaminants. Concern is mounting about the negative effects of environmental estrogens on fish reproduction; however, in environmental mixtures, the affects from estrogenic compounds may be suppressed by aryl hydrocarbon receptor (AhR) ligands. Indeed, reductions in 17beta-estradiol-induced (0.01 and 1 mg/kg) vitellogenin (VTG) levels were observed in white sturgeon coinjected with beta-naphthoflavone (BNF; 50 mg/kg), a model for contaminants that activate the AhR. Variation in the time of injection was used to attempt to correlate VTG inhibition to ethoxyresorufin-O-deethylase activity. No evidence was found to suggest that the inhibition of VTG is a direct result of enhanced estrogen metabolism by BNF-induced enzymes. Results of the present study are relevant for monitoring programs that measure VTG, because these results show that AhR-active environmental contaminants can repress VTG synthesis, which commonly is used as an indicator of estrogen-mimicking contaminants. Furthermore, suppression of natural estrogen signaling by AhR agonists may have significant effects on fish reproduction.

  10. Quality attributes and microbial storage stability of caviar from cultivated white sturgeon (Acipenser transmontanus).

    PubMed

    Shin, Joong-Han; Oliveira, Alexandra C M; Rasco, Barbara A

    2010-01-01

    Caviar was prepared from white sturgeon (Acipenser transmontanus) roe by adjusting the water phase salt (WPS) to 4.0% to 6.3% by adding food grade NaCl. Fish were obtained from 2 different farms from the Inland Northwest (N = 5). Salt was absorbed at a different rate and to a different extent by roe from different fish. The lipid content in the fish roe varied from 10.2% to 14.4% (w/w), with palmitic acid and oleic acid being the most abundant saturated and monounsaturated fatty acids present, respectively. The caviar contained high levels of polyunsaturated fatty acids (PUFA) (35% to 37%) with docosahexanoic acid being the most abundant omega-3 long chain fatty acid. There were no significant differences in microbial storage stability for caviars from different fish stored at 3 degrees C. However, for caviar stored at 7 degrees C, there was less growth of Listeria monocytogenes (using a cocktail of ATCC 19114, 7644, 19113 strains) in 2 samples (2B46 and 0F05) until day 20. In 2 other samples (453F and 2519), which had lower initial microbial loads, less overall microbial growth was observed, indicating that culture and harvest practices result in compositional differences between fish, which may impact both product composition and storage stability.

  11. Comparison of fin ray sampling methods on white sturgeon Acipenser transmontanus growth and swimming performance.

    PubMed

    Nguyen, P L; Jackson, Z J; Peterson, D L

    2016-02-01

    Effects of two fin-ray sampling methods on swimming performance, growth and survival were evaluated for hatchery-reared sub-adult white sturgeon Acipenser transmontanus. Fish were subjected to either a notch removal treatment in which a small section was removed from an anterior marginal pectoral-fin ray, or a full removal treatment in which an entire marginal pectoral-fin ray was removed. Control fish did not have fin rays removed, but they were subjected to a sham operation. A modified 3230 l Brett-type swim tunnel was used to evaluate 10 min critical station-holding speeds (SCSH ) of A. transmontanus, immediately after the fin ray biopsies were obtained with each method. Survival and growth were evaluated over a 6 month period for a separate group of fish subjected to the same biopsy methods. Mean ± S.E. 10 min SCSH were 108·0 ± 2·3, 110·0 ± 2·6 and 115·0 ± 3·5 cm s(-1) for the notch removal group, full removal group and control group, respectively, and were not significantly different among treatments. Behavioural characteristics including tail-beat frequency and time spent hunkering were also not significantly different among treatment groups swimming at the same speeds. There were no mortalities and relative growth was similar among treatment groups. Average biopsy time for the notch removal method was lower and the wounds appeared to heal more quickly compared with the full removal method.

  12. Unscreened water-diversion pipes pose an entrainment risk to the threatened green sturgeon, Acipenser medirostris.

    PubMed

    Mussen, Timothy D; Cocherell, Dennis; Poletto, Jamilynn B; Reardon, Jon S; Hockett, Zachary; Ercan, Ali; Bandeh, Hossein; Kavvas, M Levent; Cech, Joseph J; Fangue, Nann A

    2014-01-01

    Over 3,300 unscreened agricultural water diversion pipes line the levees and riverbanks of the Sacramento River (California) watershed, where the threatened Southern Distinct Population Segment of green sturgeon, Acipenser medirostris, spawn. The number of sturgeon drawn into (entrained) and killed by these pipes is greatly unknown. We examined avoidance behaviors and entrainment susceptibility of juvenile green sturgeon (35±0.6 cm mean fork length) to entrainment in a large (>500-kl) outdoor flume with a 0.46-m-diameter water-diversion pipe. Fish entrainment was generally high (range: 26-61%), likely due to a lack of avoidance behavior prior to entering inescapable inflow conditions. We estimated that up to 52% of green sturgeon could be entrained after passing within 1.5 m of an active water-diversion pipe three times. These data suggest that green sturgeon are vulnerable to unscreened water-diversion pipes, and that additional research is needed to determine the potential impacts of entrainment mortality on declining sturgeon populations. Data under various hydraulic conditions also suggest that entrainment-related mortality could be decreased by extracting water at lower diversion rates over longer periods of time, balancing agricultural needs with green sturgeon conservation.

  13. Inheritance of microsatellite loci in the polyploid lake sturgeon (Acipenser fulvescens)

    USGS Publications Warehouse

    Pyatskowit, J.D.; Krueger, C.C.; Kincaid, H.L.; May, B.

    2001-01-01

    Inheritance in the expression of amplicons for four microsatellite primer pairs was determined using 10 families created from gametes of wild lake sturgeon (Acipenser fulvescens). Loci Afu34 and Afu68 expressed a maximum of two even-intensity bands per individual and had progeny genotype ratios that fit disomic inheritance (P > 0.05). Some variation exhibited at Afu34 and Afu68 was attributable to a null allele. Genotype expression at both loci also indicated that one female parent had transmitted unreduced gametes. Primer Afu39 amplified products that exhibited four gene doses, where genotype counts fit expected ratios for disomic inheritance (P > 0.05) indicating amplification of products from two disomic loci that share alleles. Meiotic drive was evident at the Afu39 loci based on a test for random segregation (P < 0.05). Only the expression of Afu19 gave evidence of tetrasomic inheritance based on a single progeny potentially produced by a double reduction gamete. No evidence for proposed octoploid inheritance was observed.

  14. Characterization and inhibition studies of carbonic anhydrase from gill of Russian Sturgeon Fish (Acipenser gueldenstaedtii).

    PubMed

    Dinçer, Barbaros; Ekinci, Arife Pınar; Akyüz, Gülay; Kurtoğlu, İlker Zeki

    2016-12-01

    An α-carbonic anhydrase (CA, EC 4.2.1.1) was purified and characterized kinetically from gill of Acipenser gueldenstaedtii as an endangered sturgeon species. The carbonic anhydrase was purified 66-folds with yield 20.7% by Sepharose-4B-l-tyrosine-sulfanilamide affinity column and the specific activity was determined as 222.2 EU/mg protein. Km and Vmax kinetic values for gill carbonic anhydrase were calculated by a Lineweaver-Burk graph using p-nitrophenol acetate (p-NPA) as a substrate, and was defined as 2.5 mM and 5 × 10(6 )μM/min, respectively. It was observed that CA from the sturgeon gill in the presence of the sulfanilamide and acetazolamide as an inhibitor had very low IC50 values such as 13.0 and 0.1 μM, respectively. In addition, it was determined that the enzyme was inhibited by Fe(2+,) Co(2+,) Ni(2+), and Zn(2+)-Ba(2+) with the IC50 values of 0.2, 1.7, 1.2, and 1.1 mM, respectively.

  15. Comparative transcriptome analysis of testes and ovaries for the discovery of novel genes from Amur sturgeon (Acipenser schrenckii).

    PubMed

    Jin, S B; Zhang, Y; Dong, X L; Xi, Q K; Song, D; Fu, H T; Sun, D J

    2015-12-29

    Sturgeons (Acipenser schrenckii) are of high evolutionary, economic, and conservation value, and caviar isone of the most valuable animal food products in the world. The Illumina HiSeq2000 sequencing platform was used to construct testicular and ovarian transcriptomes to identify genes involved in reproduction and sex determination in A. schrenckii. A total of 122,381 and 114,527 unigenes were obtained in the testicular and ovarian transcriptomes, respectively, with average lengths of 748 and 697 bp. A total of 46,179 genes were matched to the non-redundant nr database. GO (31,266), KEGG (39,712), and COG analyses (20,126) were performed to identify potential genes and their functions. Twenty-six gene families involved in reproduction and sex determination were identified from the A. schrenckii testicular and ovarian transcriptomes based on functional annotation of non-redundant transcripts and comparisons with the published literature. Furthermore, 1309 unigenes showed significant differences between the testes and ovaries, including 782 genes that were up-regulated in the testes and 527 that were up-regulated in the ovaries. Eleven genes were involved in reproduction and sex determination mechanisms. Furthermore, 19,065 simple sequence repeats (SSRs) were identified in the expressed sequence tagged dataset, and 190,863 and 193,258 single nucleotide polymorphisms (SNPs) were obtained from the testicular and ovarian transcriptomic databases, respectively. This study provides new sequence information about A. schrenckii, which will provide a basis for the further study of reproduction and sex determination mechanisms in Acipenser species. The potential SSR and SNP markers isolated from the transcriptome may shed light on the evolution and molecular ecology of Acipenser species.

  16. Ontogenetic behavior and migration of Volga River Russian sturgeon, Acipenser gueldenstaedtii, with a note on adaptive significance of body color

    USGS Publications Warehouse

    Kynard, B.; Zhuang, P.; Zhang, L.; Zhang, T.; Zhang, Z.

    2002-01-01

    We conducted laboratory experiments with Volga River Russian sturgeon, Acipenser gueldenstaedtii, to develop a conceptual model of early behavior. We daily observed fish from day-0 (embryos, first life interval after hatching) to day-29 feeding larvae for preference of bright habitat and cover, swimming distance above the bottom, up- and downstream movement, and diel activity. Hatchling embryos initiated a downstream migration, which suggests that predation risk of embryos at spawning sites is high. Migration peaked on days 0-5 and ceased on day 7 (8-day migration). Migrants preferred bright, open habitat and early migrants swam-up far above the bottom (maximum daily median, 140 cm) in a vertical swim tube. Post-migrant embryos did not prefer bright illumination but continued to prefer white substrate, increased use of cover habitat, and swam on the bottom. Larvae initiated feeding on day 10 after 170.6 cumulative temperature degree-days. Larvae did not migrate, weakly preferred bright illumination, preferred white substrate and open habitat, and swam near the bottom (daily median 5-78 cm). The lack of a strong preference by larvae for bright illumination suggests foraging relies more on olfaction than vision for locating prey. A short migration by embryos would disperse wild sturgeon from a spawning area, but larvae did not migrate, so a second later migration by juveniles disperses young sturgeon to the sea (2-step migration). Embryo and larva body color was light tan and tail color was black. The migration, behavior, and light body color of Russian sturgeon embryos was similar to species of Acipenser and Scaphirhynchus in North America and to Acipenser in Asia that migrate after hatching as embryos. The similarity in migration style and body color among species with diverse phylogenies likely reflects convergence for common adaptations across biogeographic regions. ?? 2002 Kluwer Academic Publishers.

  17. Distribution of somatostatin immunoreactive neurons and fibres in the central nervous system of a chondrostean, the Siberian sturgeon (Acipenser baeri).

    PubMed

    Adrio, Fátima; Anadón, Ramón; Rodríguez-Moldes, Isabel

    2008-05-13

    Somatostatin (SOM) is a neuropeptide that is widely distributed in the central nervous system of vertebrates. Two isoforms of somatostatin (SS1 and SS2) have been characterized in sturgeon and in situ hybridisation studies in the sturgeon brain have demonstrated that mRNAs of the two somatostatin precursors (PSS1 and PSS2) are differentially expressed in neurons [Trabucchi, M., Tostivint, H., Lihrmann, I., Sollars, C., Vallarino, M., Dores, R.M., Vaudry, H., 2002. Polygenic expression of somatostatin in the sturgeon Acipenser transmontanus: molecular cloning and distribution of the mRNAs encoding two somatostatin precursors. J. Comp. Neurol. 443, 332-345.]. However, neither the morphology of somatostatinergic neurons nor the patterns of innervation have yet been characterized. To gain further insight into the evolution of this system in primitive bony fishes, we studied the distribution of somatostatin-immunoreactive (SOM-ir) cells and fibres in the brain of the Siberian sturgeon (Acipenser baeri). Most SOM-ir cells were found in the preoptic area and hypothalamus and abundant SOM-ir fibres coursed along the hypothalamic floor towards the median eminence, suggesting a hypophysiotrophic role for SOM in sturgeon. In addition, SOM-ir cells and fibres were observed in extrahypothalamic regions such as the telencephalon thalamus, rhombencephalon and spinal cord, which also suggests neuromodulatory and/or neurotransmitter functions for this peptide. Overall there was a good correlation between the distribution of SOM-ir neurons throughout the brain of A. baeri and that of PSS1 mRNA in Acipenser transmontanus. Comparative analysis of the results with those obtained in other groups of fishes and tetrapods indicates that widespread distribution of this peptide in the brain is shared by early vertebrate lines and that the general organization of the somatostatinergic systems has been well-conserved during evolution.

  18. Effects of age and size on critical swimming speed of juvenile Chinese sturgeon Acipenser sinensis at seasonal temperatures.

    PubMed

    He, X; Lu, S; Liao, M; Zhu, X; Zhang, M; Li, S; You, X; Chen, J

    2013-03-01

    Changes in the critical swimming speed (Ucrit , cm s(-1) ) with ontogeny of 2·5-12·5 month-old juvenile anadromous Chinese sturgeon Acipenser sinesis were measured in a modified Blazka-type swimming tunnel. The absolute Ucrit increased with length, mass and age; the relative U(')crit (body lengths, s(-1) ), however, decreased. Juvenile A. sinesis did not display a parr-smolt transformation at the length or age threshold to tolerate full-strength seawater.

  19. Metabolic changes in droplet vitrified semen of wild endangered Persian sturgeon Acipenser persicus (Borodin, 1997).

    PubMed

    Abed-Elmdoust, Amirreza; Farahmand, Hamid; Mojazi-Amiri, Bagher; Rafiee, Gholamreza; Rahimi, Ruhollah

    2017-03-21

    Comparative quantitative metabolite profiling can be used for better understanding of cell functions and dysfunctions in particular circumstances such as sperm banking which is an important approach for cryopreservation of endangered species. Cryopreservation techniques have some deleterious effects on spermatozoa which put the obtained results in controversy. Therefore, in the present study, quantitative (1)H NMR (Nuclear Magnetic Resonance) based metabolite profiling was conducted to evaluate metabolite changes related to energetics and some other detected metabolites in vitrified semen of critically endangered wild Acipenser persicus. The semen was diluted with extenders containing 0, 5, 10, and 15 μM of fish antifreeze protein (AFP) type III as a cryoprotectant. Semen-extenders were vitrified and stored for two days. Based on post-thaw motility duration and motility percentage assessments, two treatments with 10 μM and 0 μM of AFP had the highest and the lowest motility percentages respectively and they were objected to (1)H NMR spectroscopy investigations in order to reveal the extremes of the metabolites dynamic range. Univariate (ANOVA) and multivariate (PCA) analysis of the resulting metabolic profiles indicated significant changes (P > 0.05) in metabolites. The level of some metabolites including acetate, adenine, creatine, creatine phosphate, lactate, betaine, sarcosine, β-alanine and trimethylamine N-oxide significantly decreased in vitrified semen while some others such as creatinine, guanidinoacetate, N, N-dimethylglycine, and glycine significantly increased. There were also significant differences between vitrified treatments in levels of creatine, creatine phosphate, creatinine, glucose, guanidinoacetate, lactate, N, N-dimethylglycine, and glycine, suggesting how fish AFP type III can be effective as a cryoprotectant.

  20. Exposure of Persian sturgeon (Acipenser persicus) to cadmium results in biochemical, histological and transcriptional alterations.

    PubMed

    Miandare, Hamed Kolangi; Niknejad, Mahtab; Shabani, Ali; Safari, Roghieh

    2016-01-01

    Sturgeon is one of the endangered families of fish in the Caspian Sea region, where there is up to 80% of their global caching. Unfortunately, in recent years, increase of pollutants has been resulted in their total population reduction. Due to their benthic nature, sturgeons are at great risk of exposing to contaminants such as cadmium. Despite their endangered status in the Caspian Sea, there are only a few studies on characterizing the relative sensitivity of sturgeons to cadmium. Adverse effects associated with pollution on angiogenesis are mediated by hypoxia inducing factor-1 (HIF-1) and vascular endothelial growth factor (VEGF). In this investigation, gene expression of two distinct HIFs-1, HIF-1α and HIF-2α, and VEGF was investigated at the mRNA transcript levels after exposure of Persian sturgeon (Acipenser persicus) to cadmium. VEGF, HIF-1α and HIF-2α expressions in treated Persian sturgeon were greater than controls. Significant increases (P<0.05) were also observed in cortisol and glucose levels compared to the control group especially in the fish exposed to higher cadmium concentration (800 μg/L). Plasma aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactic acid dehydrogenase (LDH) levels were increased in the cadmium-exposed fish, although the observed increases were not significant between the control and 200 μg/L cadmium treatment at some sampling time points. Gill tissues also showed histopathological changes in the cadmium treatments. Overall, results indicated that cadmium resulted in some alterations in biochemical parameters, mRNA transcript level expression of two important angiogenesis related genes as well as histological alterations in Persian sturgeon.

  1. The physiological responses of green sturgeon (Acipenser medirostris) to potential global climate change stressors.

    PubMed

    Sardella, Brian A; Kültz, Dietmar

    2014-01-01

    The green sturgeon (Acipenser medirostris) is an anadromous species with a distinct population segment in the San Francisco Bay-Sacramento River Delta that is currently listed as threatened. Although this species is able to tolerate salinity challenges as soon as 6 mo posthatch, its ability to deal with unpredictable salinity fluctuations remains unknown. Global climate change is predicted to result in large freshwater (FW) flushes through the estuary during winter and greater tidal influence during the summer. We exposed green sturgeon acclimated to 15 (EST) or 24 (BAY) g/L salinity to a rapid FW influx, where salinity was reduced to 0 g/L in 3 h in order to simulate the effect of the "winter" scenario. Both groups survived, enduring a 10% plasma osmolality reduction after 3 h. BAY-acclimated sturgeon upregulated both Na(+), K(+)-ATPase (NKA) activity and caspase 3/7 activity, but no changes were observed in the EST-acclimated fish. In addition, we exposed FW-acclimated sturgeon to a dual 12-h salinity fluctuation cycle (0-24-0 g/L) in order to simulate the effect of greater tidal influence. At 6 h, the sturgeon showed a significant increase in plasma osmolality, and branchial NKA and caspase 3/7 activities were increased, indicating an acclimation response. There was no acclimation at 18 h, and plasma osmolality was higher than the peak observed at 6 h. The second fluctuation elicited an upregulation of the stress proteins ubiquitin and heat shock 70-kDa protein (HSP 70). Sturgeon can acclimate to changes in salinity; however, salinity fluctuations resulted in substantial cellular stress.

  2. Intraperitoneal injection urocortin-3 reduces the food intake of Siberian sturgeon (Acipenser baerii).

    PubMed

    Zhang, Xin; Wu, Yuanbing; Hao, Jin; Zhu, Jieyao; Tang, Ni; Qi, Jinwen; Wang, Shuyao; Wang, Hong; Peng, Shuang; Liu, Ju; Gao, Yundi; Chen, Defang; Li, Zhiqiong

    2016-11-01

    Urocortin-3 (UCN3), one of the corticotropin releasing factor (CRF) family peptides, which was discovered in 2001, has a variety of biological functions. However, the researches of UCN3 in fish were scarce. In order to understand whether UCN3 play a role in regulating food intake in fish, we first cloned the ucn3 cDNAs sequence of Siberian sturgeon (Acipenser baerii Brandt), and investigated the ucn3 mRNA levels in 11 tissues. The Siberian sturgeon ucn3 cDNA sequence was 1044bp, including an open reading frame (ORF) of 447bp that encoded 148 amino acids with a mature peptide of 40 amino acids, a 5'-terminal untranslated region (5'-UTR) of 162bp and a 3'-terminal untranslated region (3'-UTR) of 435bp. The result of tissue distribution showed that ucn3 widely distributed in 11 tissues with highest expression in brain. We also assessed the effects of periprandial (pre- and post-feeding), fasting and re-feeding on ucn3 mRNAs abundance in brain. The results showed the expression of ucn3 mRNA in brain was significantly elevated after feeding, decreased after fasting 17 days and increased after re-feeding. To further investigate the food intake role of UCN3 in Siberian sturgeon, we performed intraperitoneal (i.p.) injection of Siberian sturgeon UCN3 (SsUCN3) with three doses (60, 120 or 240ng/g) and recorded the food intake. Acute and chronic i.p. injection SsUCN3 reduced the food intake in a dose-dependent pattern. In conclusion, this study indicates that SsUCN3 acts as a satiety factor to inhibit the food intake of Siberian sturgeon.

  3. Effect of nutritional status on the osmoregulation of green sturgeon (Acipenser medirostris).

    PubMed

    Haller, Liran Y; Hung, Silas S O; Lee, Seunghyung; Fadel, James G; Lee, Jun-Ho; McEnroe, Maryann; Fangue, Nann A

    2015-01-01

    Anthropogenic climate change is linked to food web and salinity fluctuations in estuarine environments. Both decreased nutritional status and environmental salinity influence the physiological tolerance and health of fish populations; however, limited information on the interaction of these two factors and their physiological consequences is available. The green sturgeon (Acipenser medirostris) is a species of special concern in California, and the southern distinct population segment is listed as threatened. To test the hypothesis that poor nutrition negatively affects osmoregulation, juvenile green sturgeon (222 d posthatch) were randomly assigned to four feed restriction groups (12.5%, 25%, 50%, and 100% of the optimal feeding rate for 4 wk). Fish were then acutely exposed to 0-, 8-, 16-, or 32-ppt salinities and sampled at three time points (12, 72, or 120 h). Feed restriction significantly (P < 0.05) decreased specific growth rate, feed efficiency, condition factor, whole-body lipids, and protein content as well as plasma glucose, triglycerides, and proteins. Furthermore, feed restriction, salinity concentration, and salinity exposure time had significant effects on hematological indexes (hematocrit, hemoglobin), plasma values (osmolality, Na(+), K(+), Cl(-), glucose, lactate, cortisol), enzymatic activity (gill and pyloric ceca Na(+)/K(+) ATPase), and morphology of gill mitochondria-rich cells. The largest disturbances were observed at the highest salinity treatments across all feeding regimes. In addition, the interaction between feed restriction and acute salinity exposure at the highest salinity treatment resulted in high mortality rates during the first 72 h of salinity exposure. Evaluating the interactions of these environmental stressors and their implications on green sturgeon physiological tolerance will inform restoration and management efforts in rapidly changing estuarine environments.

  4. Sequencing and De Novo Assembly of the Gonadal Transcriptome of the Endangered Chinese Sturgeon (Acipenser sinensis)

    PubMed Central

    Du, Hao; Zhang, Shuhuan; Wei, Qiwei

    2015-01-01

    Background The Chinese sturgeon (Acipenser sinensis) is endangered through anthropogenic activities including over-fishing, damming, shipping, and pollution. Controlled reproduction has been adopted and successfully conducted for conservation. However, little information is available on the reproductive regulation of the species. In this study, we conducted de novo transcriptome assembly of the gonad tissue to create a comprehensive dataset for A. sinensis. Results The Illumina sequencing platform was adopted to obtain 47,333,701 and 47,229,705 high quality reads from testis and ovary cDNA libraries generated from three-year-old A. sinensis. We identified 86,027 unigenes of which 30,268 were annotated in the NCBI non-redundant protein database and 28,281 were annotated in the Swiss-prot database. Among the annotated unigenes, 26,152 and 7,734 unigenes, respectively, were assigned to gene ontology categories and clusters of orthologous groups. In addition, 12,557 unigenes were mapped to 231 pathways in the Kyoto Encyclopedia of Genes and Genomes Pathway database. A total of 1,896 unigenes, potentially differentially expressed between the two gonad types, were found, with 1,894 predicted to be up-regulated in ovary and only two in testis. Fifty-five potential gametogenesis-related genes were screened in the transcriptome and 34 genes with significant matches were found. Besides, more paralogs of 11 genes in three gene families (sox, apolipoprotein and cyclin) were found in A. sinensis compared to their orthologs in the diploid Danio rerio. In addition, 12,151 putative simple sequence repeats (SSRs) were detected. Conclusions This study provides the first de novo transcriptome analysis currently available for A. sinensis. The transcriptomic data represents the fundamental resource for future research on the mechanism of early gametogenesis in sturgeons. The SSRs identified in this work will be valuable for assessment of genetic diversity of wild fish and genealogy

  5. Functional C1q is present in the skin mucus of Siberian sturgeon (Acipenser baerii).

    PubMed

    Fan, Chunxin; Wang, Jian; Zhang, Xuguang; Song, Jiakun

    2015-01-01

    The skin mucus of fish acts as the first line of self-protection against pathogens in the aquatic environment and comprises a number of innate immune components. However, the presence of the critical classical complement component C1q, which links the innate and adaptive immune systems of mammalians, has not been explored in a primitive actinopterygian fish. In this study, we report that C1q is present in the skin mucus of the Siberian sturgeon (Acipenser baerii). The skin mucus was able to inhibit the growth of Escherichia coli. The bacteriostatic activity of the skin mucus was reduced by heating and by pre-incubation with EDTA or mouse anti-human C1q antibody. We also detected C1q protein in skin mucus using the western blot procedure and isolated a cDNA that encodes the Siberian sturgeon C1qC, which had 44.7-51.4% identity with C1qCs in teleosts and tetrapods. A phylogenetic analysis revealed that Siberian sturgeon C1qC lies at the root of the actinopterygian branch and is separate from the tetrapod branch. The C1qC transcript was expressed in many tissues as well as in skin. Our data indicate that C1q is present in the skin mucus of the Siberian sturgeon to protect against water-borne bacteria, and the C1qC found in the sturgeon may represent the primitive form of teleost and tetrapod C1qCs.

  6. Physiological changes and reproductive performance of Sterlet sturgeon Acipenser ruthenus injected with thiamine.

    PubMed

    Ghiasi, Sareh; Falahatkar, Bahram; Arslan, Murat; Dabrowski, Konrad

    2017-03-01

    To evaluate the effects of thiamine on physiological changes and spawning performance of Sterlet sturgeon Acipenser ruthenus, 45 farmed female fish (698.6±8.9g) were randomly distributed in 9 tanks (1000L) and fed a diet with 1g/kg of an anti-thiamine drug. This was provided for 5 months prior to spawning. Thiamine hydrochloride was intraperitoneally injected to fish at three different doses: 0 (T0, as control), 5 (T5) and 50 (T50) mg/kg body weight at days 30, 90 and 150 after the experiment started. After five months, the results showed no significant differences in weight gain and hemoglobin level, but hematocrit significantly increased in T5 group. There was no significant difference in glucose-6-phosphate dehydrogenase and estradiol-17β, but testosterone was significantly increased in the T50 group. Total thiamine concentration in the eggs was significantly higher in T50 than that detected in the control group. Fecundity and larval mortality at 6day post hatch (dph) showed no significant differences among treatments, while the number of eggs per gram was significantly lower in T0 than that observed in T50. Larval weights at 1 (11.6mg) and 6 (23.1mg) dph and larval lengths at 6 (15.6mm) dph were significantly affected by the treatment with the highest level of thiamine injection (T50). Diseases symptoms such as yolk sac deformation, erratic pattern of swimming, and loss of equilibrium were observed at 4 dph in T0 and T5 groups. The overall results revealed that thiamine injection has positive effects on reproductive performance in the sturgeon and the negative impacts of anti-thiamine in the offspring can be reduced by the injection of this vitamin to the broodstock.

  7. Previtellogenic and vitellogenic oocytes in ovarian follicles of cultured siberian sturgeon Acipenser baerii (Chondrostei, Acipenseriformes).

    PubMed

    Żelazowska, Monika; Fopp-Bayat, Dorota

    2017-01-01

    Previtellogenic and vitellogenic oocytes in ovarian follicles from cultured Siberian sturgeon Acipenser baerii were examined. In previtellogenic oocytes, granular and homogeneous zones in the cytoplasm (the ooplasm) are distinguished. Material of nuclear origin, rough endoplasmic reticulum, Golgi complexes, complexes of mitochondria with cement and round bodies are numerous in the granular ooplasm. In vitellogenic oocytes, the ooplasm comprises three zones: perinuclear area, endoplasm and periplasm. The endoplasm contains yolk platelets, lipid droplets, and aggregations of mitochondria and granules immersed in amorphous material. In the nucleoplasm, lampbrush chromosomes, nucleoli, and two types of nuclear bodies are present. The first type of nuclear bodies is initially composed of fibrillar threads only. Their ultrastructure subsequently changes and they contain threads and medium electron dense material. The second type of nuclear bodies is only composed of electron dense particles. All nuclear bodies impregnate with silver, stain with propidium iodide, and are DAPI-negative. Their possible role is discussed. All oocytes are surrounded by follicular cells and a basal lamina which is covered by thecal cells. Egg envelopes are not present in previtellogenic oocytes. In vitellogenic oocytes, the plasma membrane (the oolemma) is covered by three envelopes: vitelline envelope, chorion, and extrachorion. Vitelline envelope comprises four sublayers: filamentous layer, trabecular layer 2 (t2), homogeneous layer, and trabecular layer 1 (t1). In the chorion, porous layer 1 and porous layer 2 are distinguished in most voluminous examined oocytes. Three micropylar cells that are necessary for the formation of micropyles are present between follicular cells at the animal hemisphere. J. Morphol. 278:50-61, 2017. ©© 2016 Wiley Periodicals,Inc.

  8. White sturgeon (Acipenser transmontanus) passage at the Dalles Dam, Columbia River, USA

    USGS Publications Warehouse

    Parsley, M.J.; Wright, C.D.; Van Der Leeuw, B. K.; Kofoot, E.E.; Peery, C.A.; Moser, M.L.

    2007-01-01

    White sturgeon (Acipenser transmontanus) ???95 cm TL were monitored using acoustic and radio telemetry at a large hydroelectric dam (the Dalles Dam) on the Columbia River, during March 2004 through November 2005 to determine timing and routes of passage and to characterize general movements. Transmitters were surgically implanted into 148 fish during the study; 90 were released into the tailrace and 58 into the forebay. We documented 26 passage events by 19 tagged fish: eight upstream via fish ladders and 18 downstream, mostly through open spill gates. During the study 17 fish entered the two ladders one or more times; 11 entered only the east ladder, three entered only the north ladder, and three entered both ladders at sometime. Residence time within the ladders by individual fish was variable, ranging from about 1 min to nearly 6 months (median = 7.7 h). Only six fish successfully ascended the east ladder, one fish twice. We could not unequivocally determine which fish ladder one fish used to pass upstream. Differences in construction between the north and east fish ladders may account for the greater success of the east fish ladder in passing sturgeon upstream. Changes to operations at hydroelectric dams to benefit migrating anadromous salmonids may influence upstream or downstream passage by white sturgeon. Altering patterns and timing of spill discharge, altering fish ladder entrance attraction flows, and the use of lights, sound, and partial barriers to direct other species of fish to preferred passage routes have unknown effects on sturgeon passage. A better understanding of the consequences to the metapopulation of increasing or precluding upstream or downstream passage is needed. ?? 2007 The Authors.

  9. The acute temperature tolerance of green sturgeon (Acipenser medirostris) and the effect of environmental salinity.

    PubMed

    Sardella, Brian A; Sanmarti, Enio; Kültz, Dietmar

    2008-10-01

    We investigated the effect of environmental salinity on the upper thermal tolerance of green sturgeon (Acipenser medirostris), a threatened species whose natural habitat is vulnerable to temperature and salinity variation as a result of global climate change. Freshwater (FW)-reared sturgeon were gradually acclimated to salinities representing FW, estuary water (EST), or San Francisco Bay water (BAY) at 18 degrees C, and their critical thermal maximum (CTMax) was measured by increasing temperature 0.3 degrees C/min until branchial ventilation ceased. CTMax was 34.2+/-0.09 degrees C in EST-acclimated fish, with FW- and BAY-acclimated fish CTMax at 33.7+/-0.08 and 33.7+/-0.1 degrees C, respectively. Despite the higher CTMax in EST-acclimated fish, FW-acclimated sturgeon ventilation rate reached a peak that was 2 degrees C higher than EST- and BAY-acclimated groups and had a greater range of temperatures within which they exhibited normal ventilatory function as assessed by Q10 calculation. The osmoregulatory consequences of exposure to near-lethal temperatures were assessed by measuring plasma osmolality and hematocrit, as well as white muscle, brain, and heart tissue water contents. Hematocrit was increased following CTMax exposure, most likely owing to the elevated metabolic demands of temperature increase, and plasma osmolality was significantly increased in EST- and BAY-acclimated fish, which was likely the result of a greater osmotic gradient across the gill as metabolism increased. To our knowledge, this represents the first evidence for an effect of salinity on the upper thermal tolerance of sturgeon, as well as the first investigation of the osmoregulatory consequences of exposure to near-lethal temperatures.

  10. Transmission of white sturgeon iridovirus in Kootenai River white sturgeon Acipenser transmontanus.

    PubMed

    Drennan, John D; LaPatra, Scott E; Siple, Jack T; Ireland, Sue; Cain, Kenneth D

    2006-06-12

    It is thought that white sturgeon iridovirus (WSIV) is transmitted vertically from adult white sturgeon Acipenser transmontanus to progeny, and that wild adults are carriers of this virus. Based on this assumption, egg disinfection trials were initiated using wild Kootenai River white sturgeon. Over 2 consecutive years, post-fertilized eggs were disinfected with iodine at concentrations ranging from 0 to 400 ppm. Eggs were incubated and progeny were reared on either de-chlorinated municipal or Kootenai River water. Juvenile sturgeon (mean weight 3.0 g) from these treatment groups were then subjected to a density stress (15 or 20 g(-1)) to manifest WSIV disease in individuals harboring the virus. In Year 1, mortality in all groups ranged from 6 to 37% and the use of municipal water was shown to significantly improve survival. However, WSIV infection was not detected in fish from any of the treatment groups or controls, and therefore did not contribute to the observed mortality. In Year 2, all treatment and control groups reared on Kootenai River water tested positive for WSIV infection and exhibited mortality ranging from 59 to 94%, but fish from groups reared on municipal water did not test positive for WSIV infection. This shows that that vertical transmission did not occur in this study. Horizontal transmission played a significant role in WSIV infection, but the lack of infection in Year 1 suggests a cyclic occurrence of the virus in the Kootenai River system. Although survival tended to be better in iodine-treated groups, the effects of iodine treatment in relation to WSIV transmission remain unknown. An important finding is that not all wild white sturgeon broodstock yield WSIV-positive progeny.

  11. White sturgeon (Acipenser transmontanus) acid-base regulation differs in response to different types of acidoses.

    PubMed

    Shartau, Ryan B; Baker, Dan W; Brauner, Colin J

    2017-03-11

    White sturgeon (Acipenser transmontanus) completely protect intracellular tissue pH (pHi) despite large reductions in extracellular (blood) pH (pHe), termed preferential pHi regulation, in response to elevated environmental PCO2 (hypercarbia) and in general appear to be relatively resilient to stressors. Preferential pHi regulation is thought to be associated with hypercarbia tolerance in general, but has also recently been observed to protect pHi against metabolic acidoses induced by exhaustive exercise and anoxia in a tropical air breathing catfish. We hypothesized that preferential pHi regulation may also be a general strategy of acid-base regulation in sturgeon. To address this hypothesis, severe acidoses were imposed to reduce pHe, and the presence or absence of preferential pHi regulation was assessed in red blood cells (RBC), heart, brain, liver and white muscle. A respiratory acidosis was imposed using hyperoxia, while metabolic acidoses were induced by exhaustive exercise, anoxia or air exposure. Reductions in pHe occurred following hyperoxia (0.15 units), exhaustive exercise (0.30 units), anoxia (0.10 units) and air exposure (0.35 units); all acidoses reduced RBC pHi. Following hyperoxia, heart, brain and liver pHi were preferentially regulated against the reduction in pHe, similar to hypercarbia exposure. Following all metabolic acidoses heart pHi was protected and brain pHi remained unchanged following exhaustive exercise and air exposure, however, brain pHi was reduced following anoxia. Liver and white muscle pHi were reduced following all metabolic acidoses. These results suggest preferential pHi regulation may be a general strategy during respiratory acidoses but during metabolic acidoses, the response differs between source of acidoses and tissues.

  12. Bioaccumulation and chronic toxicity of dietary L-selenomethionine in juvenile white sturgeon (Acipenser transmontanus).

    PubMed

    Tashjian, Diran H; Teh, Swee J; Sogomonyan, Arutyun; Hung, Silas S O

    2006-10-12

    An 8-week growth trial was conducted to determine the sensitivity of white sturgeon (Acipenser transmontanus) to the toxicological effects of elevated dietary selenium (Se). Juvenile white sturgeon were fed diets supplemented with Se in the form of L-selenomethionine (SeMet), resulting in dietary concentrations of 0.4, 9.6, 20.5, 41.7, 89.8, and 191.1 microg Se/g diet on a dry weight basis. Effects of dietary SeMet on survival, swimming activity, growth, whole-body proximate composition, tissue Se concentrations, and histopathology were determined. Sturgeon survival among treatment groups did not differ significantly with a mean survival rate of 99+/-0.43% across all groups. A significant decrease (p<0.05) in swimming activity and growth rate was observed in sturgeon fed at or above 41.7 microg Se/g diet. Dietary SeMet concentrations were negatively correlated with whole-body protein and lipid content, but positively correlated with ash and moisture content. Selenium accumulated in the kidney, muscle, liver, gill, and plasma tissues in a dose-dependent manner. Histopathological alterations in the liver and kidney were observed in sturgeon fed above 20.5 microg Se/g diet. The threshold dietary Se toxicity concentration for white sturgeon was estimated to lie between 10 and 20 microg Se/g diet based on the histopathological alterations in the kidney. Research examining the consequences of elevated dietary Se concentrations on more sensitive life stages and the interactive effects of Se with other chemical or physical stressors are needed in order to determine if dietary threshold should be lowered to minimize the potential impacts of Se on white sturgeon in the San Francisco Bay-Delta.

  13. Physiological and molecular responses of juvenile shortnose sturgeon (Acipenser brevirostrum) to thermal stress.

    PubMed

    Zhang, Yueyang; Loughery, Jennifer R; Martyniuk, Christopher J; Kieffer, James D

    2017-01-01

    The shortnose sturgeon (Acipenser brevirostrum LeSueur, 1818) is a vulnerable species that is found along the eastern coast of North America. Little is known about temperature tolerance in this species and with a rapidly changing global climate, it becomes increasingly important to define the thermal tolerance of this species to better predict population distribution. Using a modified critical thermal maximum test (CTMax), the objectives of this study were to determine the impact of heating rate (0.1, 0.2 and 0.25°Cmin(-1)) on the thermal tolerance, associated hematological responses, and oxygen consumption in juvenile sturgeon. In addition, transcripts associated with physiological stress and heat shock (i.e., heat shock proteins) were also measured. Heating rate did not alter the CTMax values of shortnose sturgeon. Neither heating rate nor thermal stress affected plasma sodium and chloride levels, nor the expression of transcripts that included catalase, glucocorticoid receptor, heat shock protein70 (hsp70), heat shock protein 90α (hsp90α) and cytochrome P450 1a (cyp1a). However, regardless of heating rate, thermal stress increased both plasma potassium and lactate concentrations. Glucose levels were increased at heating rates of 0.2 and 0.25°Cmin(-1), but not at 0.1°Cmin(-1). Overall, oxygen consumption rates increased with thermal stress, but the response patterns were not affected by heating rate. These data support the hypothesis that shortnose sturgeon can tolerate acute heat stress, as many physiological and molecular parameters measured here were non-responsive to the thermal stress.

  14. Age, Growth and Spatial Distribution of the Life Stages of the Shortfin Mako, Isurus oxyrinchus (Rafinesque, 1810) Caught in the Western and Central Atlantic

    PubMed Central

    Barreto, Rodrigo R.; de Farias, Wialla K. T.; Andrade, Humber; Santana, Francisco M.; Lessa, Rosangela

    2016-01-01

    The shortfin mako (Isurus oxyrinchus) is a highly migratory pelagic shark that preferentially inhabits oceanic regions in practically all oceans. The wide distribution range of this species renders it susceptible to coastal and oceanic fishing operations. The International Union for Conservation of Nature (IUCN) and the International Commission for the Conservation of Atlantic Tunas (ICCAT) consider this species to be highly vulnerable, especially due to its biological parameters, which are different from those of other sharks that occupy the same niche (e.g., Prionace glauca). Consequently, considerable declines in abundance have been detected over various parts of its range, most of which are linked to oceanic longline fishing. The species has conflicting life history parameters in studies conducted in the last 30 years, especially with regard to age and growth. The main discrepancies regard the interpretation of the periodicity of the deposition of band pairs (BPs) on vertebrae and the possibility of ontogenetic variations in growth. Shortfin mako sharks (n = 1325) were sampled by onboard observers of the Brazilian chartered pelagic longline fleet based in northeast Brazil from 2005 to 2011. Lengths were 79 to 250 and 73 to 296 cm (fork length, FL) for males and females, respectively, with a statistically significant difference in size between sexes and differences in the proportion of individuals in each size class. The onboard observers collected a subsample of vertebrae (n = 467), only 234 of which were suitable for analyses. Reliability between readings was satisfactory. However, it was not possible to validate periodicity in the formation of age bands in the sample. Thus, the von Bertalanffy growth function was used to calculate growth rates for the species through the interpretation of BPs in different scenarios: one BP per year (s1), two BPs per year (s2) and two BPs per year until five years of life (s3). Growth parameters varied for both females (Linf

  15. Cryopreservation of early stage Siberian sturgeon Acipenser baerii germ cells, comparison of whole tissue and dissociated cells.

    PubMed

    Pšenička, Martin; Saito, Taiju; Rodina, Marek; Dzyuba, Boris

    2016-04-01

    Several sturgeon species are near extinction; therefore an efficient conservation strategy is required. Germ stem cells can be used for long-term storage and restoration of genetic information using surrogate reproduction. This study compared cryopreservation procedures of early stages of Siberian sturgeon Acipenser baerii testicular and ovarian cells. Whole gonad tissue or dissociated cells were frozen at a cooling rate of 1 °C/min in phosphate buffered saline with 0.5% bovine serum albumin, 50 mM glucose, and one of four different 1.5 M cryoprotectants: dimethyl sulfoxide, glycerol, ethylene glycol, or dimethyl sulfoxide with propanediol. The number of living cells obtained from 0.1 g of gonadal tissue after freeze/thaw of both whole tissue and dissociated cells was higher using ethylene glycol than with other cryoprotectants. Although there were no differences in the number of living cells in cryopreserved whole tissue vs. dissociated cells, the number of dead cells was lower with whole tissue cryopreservation, indicating that cells that died during freeze/thaw were digested during subsequent enzymatic dissociation. This resulted in more than 90% live cells after freeze/thaw and dissociation. The thawed tissue cryopreserved using ethylene glycol as protectant as well as fresh gonadal tissue were dissociated, and the cells were labelled by PKH26 and transplanted into larvae of sterlet Acipenser ruthenus. Ninety days post-transplant of both fresh and cryopreserved cells, introduced cells proliferated in more than half of the recipients.

  16. Optimization of enzyme-assisted extraction and characterization of collagen from Chinese sturgeon (Acipenser sturio Linnaeus) skin

    PubMed Central

    Feng, Weiwei; Zhao, Ting; Zhou, Ye; Li, Fang; Zou, Ye; Bai, Shiqi; Wang, Wei; Yang, Liuqing; Wu, Xiangyang

    2013-01-01

    Background: Sturgeon (Acipenser sturio Linnaeus) skin contains high amount of nutrients including unsaturated fatty acids and collagen. A pepsin-assisted extraction procedure was developed and optimized for the extraction of collagen from Chinese sturgeon (Acipenser sturio Linnaeus) skins. Objective: To determine the optimum conditions with the maximum yield of the pepsin-soluble collagen (PSC) extraction. Materials and Methods: The conditions of the extraction were optimized using response surface methodology. The Box–Behnken design was used to evaluate the effects of the three independent variables (extraction time, enzyme concentration, and solid–liquid ratio) on the PSC yield of the sturgeon skin. Results: The optimal conditions were: solid–liquid ratio of 1:11.88, enzyme concentration of 2.42%, and extraction time of 6.45 h. The maximum yield of 86.69% of PSC was obtained under the optimal conditions. This value was not significantly different from the predicted value (87.4%) of the RSM (P < 0.05). Conclusion: The results of this study indicated that the production of PSC from sturgeon skin is feasible and beneficial. The patterns of sodium dodecyl sulfate-polyacrylamide gel electrophoretic patterns (SDS-PAGE) indicated that the sturgeon skin contains type I collagen, which is made of α-chain and β-chain. The infrared spectra of the collagens also indicated that pepsin hydrolysis does not affect the secondary structure of collagen, especially triple-helical structure. PMID:24143042

  17. A new deropristiid species (Trematoda: Deropristiidae) from the lake sturgeon Acipenser fulvescens in Wisconsin, and its biogeographical implications.

    PubMed

    Choudhury, Anindo

    2009-10-01

    Pristicola bruchi n. sp. (Trematoda: Deropristiidae) is described from the spiral-valved intestine of the lake sturgeon, Acipenser fulvescens, from the Wolf River in Wisconsin, United States. It differs from the only other species of the genus, Pristicola sturionis, a parasite of the European Atlantic sturgeon Acipenser sturio, in being smaller and in possessing the following characters: a single row of conspicuous peg-like oral spines instead of 2 rows; vitelline follicles that are dorsally confluent over only a small region and that barely overlap the testes instead of extending beyond the posterior testes; and a shorter hermaphroditic duct. Comparisons are hindered by the fact that the type material of P. sturionis is no longer available. This is the first report of the genus in North America and is, apparently, the first time the genus has been reported in sturgeon anywhere since the description of P. sturionis in 1930. The presence of a species of Pristicola in North America means that all 3 genera of deropristiids, Deropristis, Pristicola, and Skrjabinopsolus, now have 2 described species, 1 in North America and another in Europe, reinforcing the amphi-Atlantic biogeography of the family. This, in turn, supports the contention that the deropristiids had diversified into the 3 generic lineages before the establishment of the North Atlantic, and that the present day distribution was likely effected by historical vicariance processes. The association of species of Pristicola and Skrjabinopsolus with the exclusively freshwater lake sturgeon in the interior of the continent also indicates their considerable geological age.

  18. Transcriptome Sequencing, De Novo Assembly and Differential Gene Expression Analysis of the Early Development of Acipenser baeri

    PubMed Central

    Song, Wei; Jiang, Keji; Zhang, Fengying; Lin, Yu; Ma, Lingbo

    2015-01-01

    The molecular mechanisms that drive the development of the endangered fossil fish species Acipenser baeri are difficult to study due to the lack of genomic data. Recent advances in sequencing technologies and the reducing cost of sequencing offer exclusive opportunities for exploring important molecular mechanisms underlying specific biological processes. This manuscript describes the large scale sequencing and analyses of mRNA from Acipenser baeri collected at five development time points using the Illumina Hiseq2000 platform. The sequencing reads were de novo assembled and clustered into 278167 unigenes, of which 57346 (20.62%) had 45837 known homologues proteins in Uniprot protein databases while 11509 proteins matched with at least one sequence of assembled unigenes. The remaining 79.38% of unigenes could stand for non-coding unigenes or unigenes specific to A. baeri. A number of 43062 unigenes were annotated into functional categories via Gene Ontology (GO) annotation whereas 29526 unigenes were associated with 329 pathways by mapping to KEGG database. Subsequently, 3479 differentially expressed genes were scanned within developmental stages and clustered into 50 gene expression profiles. Genes preferentially expressed at each stage were also identified. Through GO and KEGG pathway enrichment analysis, relevant physiological variations during the early development of A. baeri could be better cognized. Accordingly, the present study gives insights into the transcriptome profile of the early development of A. baeri, and the information contained in this large scale transcriptome will provide substantial references for A. baeri developmental biology and promote its aquaculture research. PMID:26359664

  19. Effects of Temperature on In Vitro Short-Term Storage of Sterlet Sturgeon (Acipenser Ruthenus) Ova.

    PubMed

    Linhart, O; Shelton, W L; Tučková, V; Rodina, M; Siddique, Mam

    2016-02-01

    Artificial propagation of sturgeons is becoming increasingly important for recovery efforts as well as for commercial production. Sterlet Acipenser ruthenus is a common Eurasian sturgeon with a small body size and one of the fastest reproductive cycles among the sturgeons. The practical question being addressed in this study was how long fertilization of ovulated eggs can be delayed without substantially reducing the hatching rate, and an ancillary question is under what' temperature conditions do eggs retain good quality. Broodstock were injected with homogenized carp pituitary extract (CPE); ovulated eggs from three females were allocated to various treatment groups for temperature storage (control, 7°C, 11°C, 15°C and 19°C) until fertilized. Storage times at the regulated temperatures prior to fertilization were for 2.5, 5.0, 7.5 and 10.0 h. After the selected storage times in ovarian fluid, eggs were fertilized and transferred to incubation cages and then they were counted. Three replicates were allocated to each storage period and temperature. Hatched larvae were counted at 7-day post-fertilization. We found that sterlet eggs do not need to be fertilized immediately after collection. Reasonably good quality was retained for several hours if temperature conditions are fairly cool and stable. Eggs retained good quality when stored at 7°C and 11°C for up to 10 h with 54.1 ± 2.9 to 69.9 ± 7.9% hatching success, but egg quality was significantly reduced after 5-h storage at 19°C (p < 0.01) and 7.5-h storage at 15°C (p < 0.05) compared to cooler temperatures. Uniform temperatures between 7°C and 11°C can be considered as appropriate for storage of eggs in ovarian fluid for up to 10 h. This information can have practical application to routine hatchery practice for acipenserids, as well as for certain research protocols.

  20. Is hepatic oxidative stress a main driver of dietary selenium toxicity in white sturgeon (Acipenser transmontanus)?

    PubMed

    Zee, Jenna; Patterson, Sarah; Wiseman, Steve; Hecker, Markus

    2016-11-01

    Most species of sturgeon have experienced significant population declines and poor recruitment over the past decades, leading many, including white sturgeon (Acipenser transmontanus), to be listed as endangered. Reasons for these declines are not yet fully understood but benthic lifestyle, longevity, and delayed sexual maturation likely render sturgeon particularly susceptible to factors such as habitat alteration and contaminant exposures. One contaminant of particular concern to white sturgeon is selenium (Se), especially in its more bioavailable form selenomethionine (SeMet), as it is known to efficiently bioaccumulate in prey items of this species. Studies have shown white sturgeon to be among the most sensitive species of fish to dietary SeMet as well as other pollutants such as metals, dioxin-like chemicals and endocrine disrupters. One of the primary hypothesized mechanisms of toxicity of SeMet in fish is oxidative stress; however, little is know about the specific mode by which SeMet affects the health of white sturgeon. Therefore, the aim of this study was to characterize oxidative stress and associated antioxidant responses as a molecular event of toxicity, and to link it with the pathological effects observed previously. Specifically, three-year-old white sturgeon were exposed for 72 days via their diet to 1.4, 5.6, 22.4 or 104.4µg Se per g feed (dm). Doses were chosen to range over a necessary Se intake level, current environmentally relevant intakes and an intake representing predicted increases of Se release. Lipid hydroperoxides, which are end products of lipid oxidation, were quantified as a marker of oxidative stress. Changes in gene expression of glutathione peroxidase (GPx), superoxide dismutase, catalase, glutathione S-transferase, apoptosis inducing factor and caspase 3 were quantified as markers of the response to oxidative stress. Concentrations of lipid hydroperoxides were highly variable within dose groups and no dose response was observed

  1. Seasonal distribution of Gulf of Mexico sturgeon in the pensacola bay system, Florida

    USGS Publications Warehouse

    Duncan, M.S.; Wrege, B.M.; Parauka, F.M.; Isely, J.J.

    2011-01-01

    Temporal and spatial distributions of Gulf of Mexico (Gulf) sturgeon Acipenser oxyrinchus desotoi were assessed in the Pensacola bay system, Florida, using stationary ultrasonic telemetry. Fifty-eight Gulf sturgeon were tagged within the Escambia (n=26), Yellow (n=8), Blackwater (n=12) and Choctawhatchee Rivers (n=12) in June, July, September and October, 2005. Fifty-four Gulf sturgeon were detected at least once during the study. Migration of sturgeon occurred throughout the bay system in fall, to various winter habitats in the Gulf of Mexico and Santa Rosa Sound. In spring, tagged sturgeon migrated back through the bay system to summer habitats in rivers. Based on the duration and number of detections, Gulf sturgeon primarily used the upper portions of East and Escambia Bays as migration routes in and out of all rivers during spring and summer and inhabited the lower portion of Pensacola Bay for longer durations in fall and winter. Specific areas within the Pensacola bay system were used in summer and winter that were not previously documented as essential sturgeon habitat. Areas in southeastern Pensacola Bay were heavily used during winter by a large portion of the population. Gulf sturgeon also exhibited long-term winter residency in Santa Rosa Sound for two consecutive years. An area in northeastern Escambia Bay supported Gulf sturgeon during the summer, which was unexpected and can not be explained by the data from this study. However, the discovery that Gulf sturgeon remain in the bay during the summer has important ecological and management implications that need further investigation. ?? 2011 Blackwell Verlag, Berlin.

  2. Habitat used by juvenile lake sturgeon (Acipenser fulvescens) in the North Channel of the St. Clair River (Michigan, USA)

    USGS Publications Warehouse

    Boase, James C.; Manny, Bruce A.; Donald, Katherine A.L.; Kennedy, Gregory W.; Diana, James S.; Thomas, Michael V.; Chiotti, Justin A.

    2014-01-01

    Lake sturgeon (Acipenser fulvescens) occupy the St. Clair River, part of a channel connecting lakes Huron and Erie in the Laurentian Great Lakes. In the North Channel of the St. Clair River, juvenile lake sturgeon (3–7 years old and 582–793 mm in length) were studied to determine movement patterns and habitat usage. Fourteen juveniles were implanted with ultrasonic transmitters and tracked June–August of 2004, 2005 and 2006. Telemetry data, Geographic Information System software, side-scan sonar, video images of the river bottom, scuba diving, and benthic substrate samples were used to determine the extent and composition of habitats they occupied. Juvenile lake sturgeon habitat selection was strongly related to water depth. No fish were found in 700 mm in length selected sand and gravel areas mixed with zebra mussels and areas dominated by zebra mussels, while fish < 700 mm used these habitat types in proportion to their availability.

  3. Comparison of select hematology and serum chemistry analtyes between wild-caught and aquarium-housed lake sturgeon (Acipenser fulvescens).

    PubMed

    DiVincenti, Louis; Priest, Heather; Walker, Kyle J; Wyatt, Jeffrey D; Dittman, Dawn

    2013-12-01

    Hematology and serum chemistry analytes were compared between wild-caught and aquarium-housed lake sturgeon (Acipenser fulvescens) to potentially improve understanding of medical issues in lake sturgeon. Blood samples were taken from 30 lake sturgeon exhibited in 11 institutions in the United States and from 23 experimentally stocked lake sturgeon caught in gill nets in the lower Genesee River in Rochester, New York, USA. For hematology, only segmented neutrophil count was significantly different, with wild-caught fish having a higher number of circulating neutrophils. For clinical chemistry analytes, chloride, uric acid, calcium, phosphate, glucose, aspartate aminotransferase, triglycerides, and creatine kinase were significantly different between the two cohorts. These differences are likely not clinically significant and are attributable to handling stress, variability in environmental parameters, or differences in nutritional status. This is the first report of hematology and serum chemistry values in aquarium-housed lake sturgeon and provides useful reference intervals for clinicians.

  4. Comparison of select hematology and serum chemistry analtyes between wild-caught and aquarium-housed lake sturgeon (Acipenser fulvescens)

    USGS Publications Warehouse

    DiVincenti, Louis; Priest, Heather; Walker, Kyle J.; Wyatt, Jeffrey D.; Dittman, Dawn

    2013-01-01

    Hematology and serum chemistry analytes were compared between wild-caught and aquarium-housed lake sturgeon (Acipenser fulvescens) to potentially improve understanding of medical issues in lake sturgeon. Blood samples were taken from 30 lake sturgeon exhibited in 11 institutions in the United States and from 23 experimentally stocked lake sturgeon caught in gill nets in the lower Genesee River in Rochester, New York, USA. For hematology, only segmented neutrophil count was significantly different, with wild-caught fish having a higher number of circulating neutrophils. For clinical chemistry analytes, chloride, uric acid, calcium, phosphate, glucose, aspartate aminotransferase, triglycerides, and creatine kinase were significantly different between the two cohorts. These differences are likely not clinically significant and are attributable to handling stress, variability in environmental parameters, or differences in nutritional status. This is the first report of hematology and serum chemistry values in aquarium-housed lake sturgeon and provides useful reference intervals for clinicians.

  5. Effects of acoustic tag implantation on lake sturgeon Acipenser fulvescens: lack of evidence for changes in behavior

    USGS Publications Warehouse

    Hondorp, Darryl W.; Holbrook, Christopher; Krueger, Charles C.

    2015-01-01

    An assumption of studies using acoustic telemetry is that surgical implantation of acoustic transmitters or tags does not alter behavior of tagged individuals. Evaluating the validity of this assumption can be difficult for large fish, such as adult sturgeons, not amenable to controlled laboratory experimentation. The purpose of this study was to determine if and when this assumption was valid for adult lake sturgeon Acipenser fulvescens tagged with large (34 g) acoustic transmitters and released into the St. Clair River during 2011–2014. The hypothesis that activity and reach-scale distributions of tagged and untagged lake sturgeon did not differ was tested by comparing movement frequencies, movement rates (speed-over-ground), and location-specific detection probabilities between newly-tagged lake sturgeon and presumably fully-recovered conspecifics tagged and released in prior years.

  6. Rapid development of polymorphic microsatellite markers for the Amur sturgeon (Acipenser schrenckii) using next-generation sequencing technology.

    PubMed

    Li, L M; Wei, L; Jiang, H Y; Zhang, Y; Zhang, X J; Yuan, L H; Chen, J P

    2015-07-14

    Anthropogenic activities have seriously impacted wild resources of the Amur sturgeon, Acipenser schrenckii, and more information on local and regional population genetic structure is required to aid the conservation of this species. In this study, we report the development of 12 novel polymorphic microsatellite loci using next-generation sequencing technology, and the genotyping of 24 individuals collected from a sturgeon farm. The results show that the mean number of ob-served alleles per locus is 6.6 (ranging from 2 to 17). Observed and expected heterozygosity values ranged from 0 to 0.958 and from 0.508 to 0.940, respectively. Not a single locus showed significant departure from Hardy-Weinberg equilibrium and no linkage disequilibrium was observed among any pairwise loci. These highly informative microsatellite markers will be useful for genetic diversity and population structure analyses of A. schrenckii and other species of this genus.

  7. Effects of feeding, digestion and fasting on the respiration and swimming capability of juvenile sterlet sturgeon (Acipenser ruthenus, Linnaeus 1758).

    PubMed

    Cai, Lu; Johnson, David; Fang, Min; Mandal, Prashant; Tu, Zhiying; Huang, Yingping

    2017-02-01

    The objective of this study is to provide information on changes in swimming capability and respiration of the sterlet sturgeon (Acipenser ruthenus, Linnaeus 1758) caused by different levels of fasting. Before testing, the four groups of sturgeon (body length: 12.1-15.4 cm, body mass: 10.0-20.2 g) fasted for 6 h, 2 days, 1 and 2 weeks, respectively. Swimming tests were then performed to measure critical swimming speed and oxygen consumption at 20 ± 0.5 °C. Results show: (1) Fasting times shorter than 2 days has little effect on swimming capability, but it decreases significantly when the fasting time is longer than a week. (2) After 2 weeks of fasting, swimming efficiency is significantly reduced. (3) Anaerobic capacity increases when digestion nears completion.

  8. De novo annotation of the immune-enriched transcriptome provides insights into immune system genes of Chinese sturgeon (Acipenser sinensis).

    PubMed

    Zhu, Rong; Du, He-Jun; Li, Shun-Yi; Li, Ya-Dong; Ni, Hong; Yu, Xue-Jing; Yang, Yan-Yan; Fan, Yu-Ding; Jiang, Nan; Zeng, Ling-Bing; Wang, Xing-Guo

    2016-08-01

    Chinese sturgeon (Acipenser sinensis), one of the oldest extant actinopterygian fishes with very high evolutionary, economical and conservation interest, is considered to be one of the critically endangered aquatic animals in China. Up to date, the immune system of this species remains largely undetermined with little sequence information publicly available. Herein, the first comprehensive transcriptome of immune tissues for Chinese sturgeon was characterized using Illumina deep sequencing. Over 67 million high-quality reads were generated and de novo assembled into the final set of 91,739 unique sequences. The annotation pipeline revealed that 25,871 unigenes were successfully annotated in the public databases, of which only 2002 had significant match to the existing sequences for the genus Acipenser. Overall 22,827 unigenes were categorized into 52 GO terms, 12,742 were classified into 26 KOG categories, and 4968 were assigned to 339 KEGG pathways. A more detailed annotation search showed the presence of a notable representation of immune-related genes, which suggests that this non-teleost actinopterygian fish harbors the same intermediates as in the well known immune pathways from mammals and teleosts, such as pattern recognition receptor (PRR) signaling pathway, JAK-STAT signaling pathway, complement and coagulation pathway, T-cell receptor (TCR) and B-cell receptor (BCR) signaling pathways. Additional genetic marker discovery led to the retrieval of 20,056 simple sequence repeats (SSRs) and 327,140 single nucleotide polymorphisms (SNPs). This immune-enriched transcriptome of Chinese sturgeon represents a rich resource that adds to the currently nascent field of chondrostean fish immunogenetics and furthers the conservation and management of this valuable fish.

  9. Effects of Dietary Garlic Extract on Growth, Feed Utilization and Whole Body Composition of Juvenile Sterlet Sturgeon (Acipenser ruthenus)

    PubMed Central

    Lee, Dong-Hoon; Ra, Chang-Six; Song, Young-Han; Sung, Kyung-Il; Kim, Jeong-Dae

    2012-01-01

    This study was carried out to investigate the supplemental effects of dietary garlic extract (GE) on growth performance of juvenile sterlet sturgeon (Acipenser ruthenus). The first experiment was designed to determine the optimum levels of garlic extract as growth promoter during 10 weeks. Three groups (two replicates/group) of 240 fish with mean body weight of 85 g were fed with diets containing 0 (control), 0.5 and 1.0% of GE. The highest weight gain (%) and feed efficiency (%) were found in fish groups fed with diet containing 0.5% GE. Subsequently, the supplemental effects of dietary GE was studied on growth of juvenile sterlet sturgeon (Acipenser ruthenus) with an average body weight of 59.6 g. Fish cultured in freshwater were randomly allotted to each of 10 tanks (two groups of five replicates, 20 fish/tank) and fed diets with 0.5% GE or without GE (control), respectively, at the level of 2.0% of fish body weight per day for 5 weeks. Weight gain (51.1%), feed efficiency (79.1%), specific growth rate (1.18%) and protein efficiency ratio (1.50) of fish fed 0.5% GE were significantly (p<0.05) higher than those fish fed the control diet. Significantly higher protein (PRE 20.4%) and lipid retention efficiencies (LRE, 74.5%) were also found in 0.5% GE group (p<0.05). The present results suggested that dietary GE could improve growth and feed utilization of juvenile sterlet sturgeons. PMID:25049599

  10. Comparative ontogenetic behavior and migration of kaluga, Huso dauricus, and Amur sturgeon, Acipenser schrenckii, from the Amur River

    USGS Publications Warehouse

    Zhuang, P.; Kynard, B.; Zhang, L.; Zhang, T.; Cao, W.

    2003-01-01

    We conducted laboratory experiments with kaluga, Huso dauricus, and Amur sturgeon, Acipenser schrenckii, to develop a conceptual model of early behavior. We daily observed embryos (first life phase after hatching) and larvae (period initiating exogenous feeding) to day-30 (late larvae) for preference of bright habitat and cover, swimming distance above the bottom, up- and downstream movement, and diel activity. Day-0 embryos of both species strongly preferred bright, open habitat and initiated a strong, downstream migration that lasted 4 days (3 day peak) for kaluga and 3 days (2 day peak) for Amur sturgeon. Kaluga migrants swam far above the bottom (150 cm) on only 1 day and moved day and night; Amur sturgeon migrants swam far above the bottom (median 130 cm) during 3 days and were more nocturnal than kaluga. Post-migrant embryos of both species moved day and night, but Amur sturgeon used dark, cover habitat and swam closer to the bottom than kaluga. The larva period of both species began on day 7 (cumulative temperature degree-days, 192.0 for kaluga and 171.5 for Amur sturgeon). Larvae of both species preferred open habitat. Kaluga larvae strongly preferred bright habitat, initially swam far above the bottom (median 50-105 cm), and migrated downstream at night during days 10-16 (7-day migration). Amur sturgeon larvae strongly avoided illumination, had a mixed response to white substrate, swam 20-30 cm above the bottom during most days, and during days 12-34 (most of the larva period) moved downstream mostly at night (23-day migration). The embryo-larva migration style of the two species likely shows convergence of non-related species for a common style in response to environmental selection in the Amur River. The embryo-larva migration style of Amur sturgeon is unique among Acipenser yet studied.

  11. Early life history stages of Gulf sturgeon in the Suwannee River, Florida

    USGS Publications Warehouse

    Sulak, K.J.; Clugston, J.P.

    1998-01-01

    Egg sampling confirmed that Suwannee River Gulf sturgeon Acipenser oxyrinchus desotoi, a subspecies of Atlantic sturgeon A. o. oxyrinchus use the same spawning site at river kilometer (rkm) 215 from the month of the river each year. Forty-nine eggs were recorded in 1995, and 368 were recorded in 1996. Spawning began 4-7 d after the March new moon in both years and lasted 10-11 d; in 1996, a second 10-d spawning round began on the April new moon. Developmental synchrony among eggs recovered suggested several discrete spawning events in both years. Total eggs deposited for three 1996 sampling days was estimated as 405,600-711,000/d, approximating the fecundity range of a large female Gulf sturgeon. Eggs were found only in the southern half of the river, an area with surface currents of 0.5-1.5 m/s and numerous eddies producing reverse bottom currents of 0.1-0.5 m/s. Egg substrate consisted of bedrock limestone thinly overlain by fine sand and densely distributed elliptical gravel 2-10 cm in diameter. Eggs were found predominantly in depths of 2-4 m at water temperatures of 17-21??C, conductivities of 50-100 ??S, and dissolved oxygen levels exceeding 5.0 mg/L. The Cody Scarp, 15 rkm above the spawning ground, may mark the upstream limit of spawning areas in the river. Three 2-4-month-old riverine juveniles (82-115 mm total length, TL) collected are the smallest yet captured from any river. Data for 18 riverine age-0 juveniles (to 350 mm TL) suggest that this stage lasts 6-10 months, terminating with migration of fish to the river mouth in January-February. Less than 2% of 461 juveniles captured at the estuarine river mouth (1990-1993) were under 350 mm TL. Riverine age-0 fish were collected over long shallow stretches (typically <4 m deep) of relatively barren sand (rkm 12-238).

  12. A nuclear DNA perspective on delineating evolutionarily significant lineages in polyploids: the case of the endangered shortnose sturgeon (Acipenser brevirostrum)

    USGS Publications Warehouse

    King, Timothy L.; Henderson, Anne P.; Kynard, Boyd E.; Kieffer, Micah C.; Peterson, Douglas L.; Aunins, Aaron W.; Brown, Bonnie L.

    2014-01-01

    The shortnose sturgeon, Acipenser brevirostrum, oft considered a phylogenetic relic, is listed as an “endangered species threatened with extinction” in the US and “Vulnerable” on the IUCN Red List. Effective conservation of A. brevirostrum depends on understanding its diversity and evolutionary processes, yet challenges associated with the polyploid nature of its nuclear genome have heretofore limited population genetic analysis to maternally inherited haploid characters. We developed a suite of polysomic microsatellite DNA markers and characterized a sample of 561 shortnose sturgeon collected from major extant populations along the North American Atlantic coast. The 181 alleles observed at 11 loci were scored as binary loci and the data were subjected to multivariate ordination, Bayesian clustering, hierarchical partitioning of variance, and among-population distance metric tests. The methods uncovered moderately high levels of gene diversity suggesting population structuring across and within three metapopulations (Northeast, Mid-Atlantic, and Southeast) that encompass seven demographically discrete and evolutionarily distinct lineages. The predicted groups are consistent with previously described behavioral patterns, especially dispersal and migration, supporting the interpretation that A. brevirostrum exhibit adaptive differences based on watershed. Combined with results of prior genetic (mitochondrial DNA) and behavioral studies, the current work suggests that dispersal is an important factor in maintaining genetic diversity in A. brevirostrum and that the basic unit for conservation management is arguably the local population.

  13. Electronic archival tags provide first glimpse of bathythermal habitat use by free-ranging adult lake sturgeon Acipenser fulvescens

    USGS Publications Warehouse

    Briggs, Andrew S.; Hondorp, Darryl W.; Quinlan, Henry R.; Boase, James C.; Mohr, Lloyd C.

    2016-01-01

    Information on lake sturgeon (Acipenser fulvescens) depth and thermal habitat use during non-spawning periods is unavailable due to the difficulty of observing lake sturgeon away from shallow water spawning sites. In 2002 and 2003, lake sturgeon captured in commercial trap nets near Sarnia, Ontario were implanted with archival tags and released back into southern Lake Huron. Five of the 40 tagged individuals were recaptured and were at large for 32, 57, 286, 301, and 880 days. Temperatures and depths recorded by archival tags ranged from 0 to 23.5 ºC and 0.1 to 42.4 m, respectively. For the three lake sturgeon that were at large for over 200 days, temperatures occupied emulated seasonal fluctuations. Two of these fish occupied deeper waters during winter than summer while the other occupied similar depths during non-spawning periods. This study provides important insight into depth and thermal habitat use of lake sturgeon throughout the calendar year along with exploring the feasibility of using archival tags to obtain important physical habitat attributes during non-spawning periods.

  14. Ovarian nests in cultured Russian sturgeon Acipenser gueldenstaedtii and North American paddlefish Polyodon spathula comprised of previtellogenic oocytes.

    PubMed

    Żelazowska, M; Jankowska, W; Plewniak, E; Rajek, U

    2015-06-01

    Ovarian nests in the ovaries of sexually maturing Russian sturgeon Acipenser gueldenstaedtii and North American paddlefish Polyodon spathula were investigated. They comprised early previtellogenic, diplotene stage oocytes and somatic cells. In the nucleoplasm, these oocytes contained chromatin in the form of grains, threads and lampbrush chromosomes, primary nucleoli and multiple nucleoli. Two stages of oocytes in nests were distinguished by differences in the distribution of mitochondria with distorted cristae and lipid droplets in the ooplasm. These stages were as follows: pre-early stage 1 (PE 1) and early stage 1 (EP 1) previtellogenic oocytes. In PE 1 oocytes few mitochondria with distorted cristae and lipid droplets were distributed randomly. The ooplasm of PE 1 oocytes was not differentiated into homogeneous and granular compartments. In EP 1 oocytes, mitochondria with distorted cristae were more numerous and grouped in the vicinity of the nucleus, lipid droplets accumulated near these mitochondria. In the nucleoplasm of EP 1 oocytes several low electron-dense spherical bodies, possibly Cajal bodies, were present.

  15. Discovery and identification of candidate sex-related genes based on transcriptome sequencing of Russian sturgeon (Acipenser gueldenstaedtii) gonads.

    PubMed

    Chen, Yadong; Xia, Yongtao; Shao, Changwei; Han, Lei; Chen, Xuejie; Yu, Mengjun; Sha, Zhenxia

    2016-07-01

    As the Russian sturgeon (Acipenser gueldenstaedtii) is an important food and is the main source of caviar, it is necessary to discover the genes associated with its sex differentiation. However, the complicated life and maturity cycles of the Russian sturgeon restrict the accurate identification of sex in early development. To generate a first look at specific sex-related genes, we sequenced the transcriptome of gonads in different development stages (1, 2, and 5 yr old stages) with next-generation RNA sequencing. We generated >60 million raw reads, and the filtered reads were assembled into 263,341 contigs, which produced 38,505 unigenes. Genes involved in signal transduction mechanisms were the most abundant, suggesting that development of sturgeon gonads is under control of signal transduction mechanisms. Differentially expressed gene analysis suggests that more genes for protein synthesis, cytochrome c oxidase subunits, and ribosomal proteins were expressed in female gonads than in male. Meanwhile, male gonads expressed more transposable element transposase, reverse transcriptase, and transposase-related genes than female. In total, 342, 782, and 7,845 genes were detected in intersex, male, and female transcriptomes, respectively. The female gonad expressed more genes than the male gonad, and more genes were involved in female gonadal development. Genes (sox9, foxl2) are differentially expressed in different sexes and may be important sex-related genes in Russian sturgeon. Sox9 genes are responsible for the development of male gonads and foxl2 for female gonads.

  16. Gonad histology and serum 11-KT profile during the annual reproductive cycle in sterlet sturgeon adult males, Acipenser ruthenus.

    PubMed

    Golpour, A; Broquard, C; Milla, S; Dadras, H; Baloch, A R; Saito, T; Pšenička, M

    2017-04-01

    The aim of this study was to assess monthly testicular development in the cultured breeding stock of sterlet, Acipenser ruthenus, using histological and serum sex steroid changes. Testicular development in the adult male was examined monthly and showed four distinct phases including resting, pre-spawning, spawning and post-spawning. Also, seasonal changes of the testes were described according to its variations in gonadosomatic index (GSI) during different phases of testicular development. Using histology, we identified continuous spermatogenesis and asynchronous gonad development pattern in the testes of male sterlet, which shows that regulation of annual gonadal cycle is influenced by season. Results also showed variation in the GSI value and number of spermatogenic cells according to each season during annual cycle of gonad, as the highest value of GSI was recorded during spawning phase (spring; March-May). Hormonal profiles of 11-ketotestosterone (11-KT) showed peak, which indicated a seasonal pattern of gonadal development. The 11-KT concentration increased considerably during the spermatogenesis (pre-spawning phase) and remained quite high throughout the pre-spermiation period. In the final phase of testicular development (spawning phase), the 11-KT markedly dropped. This study undertook an examination of complete reproductive development in cultured sterlet sturgeon to provide a valuable guide for the future sterlet studies, and allows comparison of reproductive development between sturgeon species.

  17. Status of White Sturgeon (Acipenser transmontanus Richardson, 1863) throughout the species range, threats to survival, and prognosis for the future

    USGS Publications Warehouse

    Hildebrand, L R; Drauch-Schreier, A; Lepla, K.; McAdam, S. O.; McLellan, J; Parsley, Michael J.; Paragamian, V L; Young, S P

    2017-01-01

    White Sturgeon, Acipenser transmontanus (WS), are distributed throughout three major river basins on the West Coast of North America: the Sacramento-San Joaquin, Columbia, and Fraser River drainages. Considered the largest North American freshwater fish, some WS use estuarine habitat and make limited marine movements between river basins. Some populations are listed by the United States or Canada as threatened or endangered (upper Columbia River above Grand Coulee Dam; Kootenai River; lower, middle and, upper Fraser River and Nechako River), while others do not warrant federal listing at this time (Sacramento-San Joaquin Rivers; Columbia River below Grand Coulee Dam; Snake River). Threats that impact WS throughout the species’ range include fishing effects and habitat alteration and degradation. Several populations suffer from recruitment limitations or collapse due to high early life mortality associated with these threats. Efforts to preserve WS populations include annual monitoring, harvest restrictions, habitat restoration, and conservation aquaculture. This paper provides a review of current knowledge on WS life history, ecology, physiology, behavior, and genetics and presents the status of WS in each drainage. Ongoing management and conservation efforts and additional research needs are identified to address present and future risks to the species.

  18. Dietary Administration of Lactobacillus plantarum Enhanced Growth Performance and Innate Immune Response of Siberian Sturgeon, Acipenser baerii.

    PubMed

    Pourgholam, Moheb Ali; Khara, Hossein; Safari, Reza; Sadati, Mohammad Ali Yazdani; Aramli, Mohammad Sadegh

    2016-03-01

    We investigated the effects of Lactobacillus plantarum used as a dietary supplement on the growth performance and innate immune response in juvenile Siberian sturgeon Acipenser baerii. Juvenile fish (14.6 ± 2.3 g) were fed three experimental diets prepared by supplementing a basal diet with L. plantarum at different concentrations [1 × 10(7), 1 × 10(8) and 1 × 10(9) colony-forming units (cfu) g(-1)] and a control (non-supplemented basal) diet for 8 weeks. Growth performance indices were increased in fish fed the 1 × 10(8) cfu g(-1) L. plantarum diet compared to the other groups. There was an increased innate immune response in fish fed the experimental diets. The highest levels of lysozyme activity, total immunoglobulin (IgM) and complement component 3 (C3) were observed in fish fed the diet containing L. plantarum at a concentration of 1 × 10(8) cfu g(-1), but there was no significant difference in the level of complement component 4 (C4) in fish fed the experimental diets or the control diet. The present study underlying some positive effects (growth performance and immune indices) of dietary administration of L. plantarum at a concentration of 1 × 10(8) cfu g(-1) in the Siberian sturgeon.

  19. Development of polysomic microsatellite markers for characterization of population structuring and phylogeography in the shortnose sturgeon (Acipenser brevirostrum)

    USGS Publications Warehouse

    Henderson, Anne P.; King, Tim L.

    2012-01-01

    Shortnose sturgeon Acipenser brevirostrum is an endangered polyploid fish species for which no nuclear DNA markers previously existed. To address this need, 86 polysomic loci were developed and characterized in 20 A. brevirostrum from five river systems and eight members (parents and six progeny) of a captive-bred family. All markers proved to be polymorphic, polysomic, and demonstrated direct inheritance when tested in a captive family. Eleven loci were included in a range-wide survey of 561 fish sampled from 17 geographic collections. Allelic diversity at these markers ranged from 7 to 24 alleles/locus and averaged 16.5 alleles/locus; sufficient diversity to produce unique multilocus genotypes. In the range-wide survey, a Mantel comparison of an ecological (1-Jaccard’s) and genetic (ΦPT; an analog to FST) distance metrics, identified a strong positive correlation (r = 0.98, P PT represents a viable metric for assessing genetic relatedness using this class of marker.

  20. Behavioural salinity preferences of juvenile green sturgeon Acipenser medirostris acclimated to fresh water and full-strength salt water.

    PubMed

    Poletto, J B; Cocherell, D E; Klimley, A P; Cech, J J; Fangue, N A

    2013-02-01

    To quantify the salinity preference of juvenile green sturgeon Acipenser medirostris, two groups of A. medirostris [140 days post hatch (dph); total length (L(T) ) 38.0-52.5 cm] were acclimated to either near fresh water (mean ± s.e. salinity = 3.2 ± 0.6) or full-strength salt water (34.1 ± 1.2) over 8 weeks. Following acclimation, the two groups were divided into experimental and control groups, where experimental A. medirostris from both freshwater and saltwater acclimations were individually introduced (200-220 dph) into a rectangular salinity-preference flume (maximum salinity gradient: 5-33). Control A. medirostris were presented with only their acclimation water (fresh water or salt water) on both sides of the flume. It was demonstrated that A. medirostris acclimated to both salt water and fresh water spent a significantly greater amount of time on the side of the testing area with the highest salinity concentration (P < 0.05 and P < 0.001, respectively) while control A. medirostris spent an equal amount of time on each side of the flume. These findings indicate that juvenile A. medirostris are not only capable of detecting salt water within the first year of their lives but perhaps are actively seeking out saline environments as they move through a watershed. Establishing A. medirostris salinity preferences provides a better understanding of the early life history of this threatened species, shedding light on possible outmigration timing.

  1. Mercury concentrations in gonad, liver, and muscle of white sturgeon Acipenser transmontanus in the lower Columbia River.

    PubMed

    Webb, M A H; Feist, G W; Fitzpatrick, M S; Foster, E P; Schreck, C B; Plumlee, M; Wong, C; Gundersen, D T

    2006-04-01

    This study determined the partitioning of total mercury in liver, gonad, and cheek muscle of white sturgeon (Acipenser transmonatus) in the lower Columbia River. The relationship between tissue mercury concentrations and various physiologic parameters was assessed. White sturgeon were captured in commercial fisheries in the estuary and Bonneville, The Dalles, and John Day Reservoirs. Condition factor (CF), relative weight (Wr), and gonadosomatic index (GSI) were determined for each fish (n = 57). Gonadal tissue was examined histologically to determine sex and stage of maturity. Liver (n = 49), gonad (n = 49), and cheek muscle (n = 57) were analyzed for total mercury using cold-vapor atomic fluorescence spectrophotometry. Tissue protein concentrations were measured by ultraviolet-visible spectroscopy. Plasma was analyzed for testosterone (T), 11-ketotestosterone (KT), and 17ss-estradiol (E2) using radioimmunoassay. Mean tissue mercury concentrations were higher in muscle compared with liver and gonad at all sampling locations, except Bonneville Reservoir where mean liver mercury content was the highest tissue concentration observed in the study. Significant negative correlations between plasma androgens (T and KT) and muscle mercury content and plasma E2 and liver mercury content were found. A significant positive linear relationship between white sturgeon age and liver mercury concentrations was evident. Significant negative correlations between CF and relative weight and gonad and liver mercury content were found. In addition, immature male sturgeon with increased gonad mercury content had decreased GSIs. These results suggest that mercury, in the form of methylmercury, may have an effect on the reproductive potential of white sturgeon.

  2. Hemato-Immunological Responses and Disease Resistance in Siberian Sturgeon Acipenser baerii Fed on a Supplemented Diet of Lactobacillus plantarum.

    PubMed

    Pourgholam, Moheb Ali; Khara, Hossein; Safari, Reza; Sadati, Mohammad Ali Yazdani; Aramli, Mohammad Sadegh

    2017-03-01

    A feeding trial was conducted to investigate the effects of different levels of dietary Lactobacillus plantarum on hemato-immunological parameters and resistance against Streptococcus iniae infection in juvenile Siberian sturgeon Acipenser baerii. Fish (14.6 ± 2.3 g) were fed three experimental diets prepared by supplementing a basal diet with L. plantarum at different concentrations [1 × 10(7), 1 × 10(8) and 1 × 10(9) colony-forming units (cfu) g(-1)] and a control (non-supplemented basal) diet for 8 weeks. Innate immune responses (immunoglobulin (Ig), alternative complement activity (ACH50) and lysozyme activity) were significantly higher in fish fed the 1 × 10(8) and 1 × 10(9) cfu g(-1) L. plantarum diet compared to the other groups (P < 0.05). Furthermore, fish fed on various levels of L. plantarum significantly showed higher red blood cell (RBC), hemoglobin (Hb), white blood cell (WBC) and monocyte compared to those of the control group (P < 0.05). At the end of the feeding experiment, some fish were challenged with S. iniae to quantify the level of disease resistance. The mortality after S. iniae challenge was decreased in fish fed a probiotic. These results indicated that dietary supplementation of L. plantarum improved immune response and disease resistance of Siberian sturgeon juvenile.

  3. Antioxidant biomarker survey ensuing long-term selenium withdrawal in Acipenser baeri fed Se-cysteine diets.

    PubMed

    Elia, Antonia Concetta; Abete, Maria Cesarina; Pacini, Nicole; Dörr, Ambrosius Josef Martin; Scanzio, Tommaso; Prearo, Marino

    2014-05-01

    Two selenium withdrawal periods, 30 and 90 days, were considered for sturgeon fed 90 days three Se-cysteine diets (1.25, 5, 20 mgkg(-1)). Subsequently Acipenser baeri was fed the previous control diet (0.32 mgSekg(-1)) for 90 days. Levels of superoxide dismutase, catalase, glutathione peroxidases, glutathione reductase, glyoxalase-II and malondialdehyde were determined in liver and kidney. Chemical analyses were carried out for the same tissues and for muscle. A reduction of Se levels in all tissues was recorded and the metalloid concentration decreased more quickly in liver than in kidney and muscle. At the end of the withdrawal Se concentration in muscle remained high in specimens previously fed 20 mgSekg(-1) diet, and disturbance of key antioxidant enzymes was recorded in liver and kidney. Moreover, alterations in glutathione peroxidases, and glyoxalase-II activities persisted even after 90 withdrawal days and were indicative of oxidative stress induced by Se-cysteine concentrations.

  4. Mycobacterium chelonae associated with tumor-like skin and oral masses in farmed Russian sturgeons (Acipenser gueldenstaedtii)

    PubMed Central

    2014-01-01

    Background Non-tuberculous mycobacteria responsible for piscine mycobacteriosis usually produce visceral granulomas in both freshwater and marine species. In this study, the first occurrence of Mycobacterium chelonae associated with tumor-like lesions in the Russian sturgeon (Acipenser gueldenstaedtii) is reported. Fifteen sturgeons from an Italian fish farm showing skin and oral cauliflower-like masses were investigated by histopathology, bacterial culture and molecular analyses. Results A total of 20 masses different in size located in the mouth and in pectoral and caudal fins (characterized by abundant calcium deposits and by mild to moderate granulomatous inflammation) were observed with a significant different degree of histological severity. All internal organs of the fish were negative for mycobacteria, Ziehl-Neelsen was positive in only one of the oral masses, whereas bacterial and PCR analyses detected the presence of M. chelonae for almost all the skin and oral masses. Based on these results, a calcinosis of dystrophic origin associated with a chronic granulomatous inflammation was considered as a primary diagnosis consequent to tissue injury in areas susceptible to trauma. Conclusions We hypothesized that the occurrence of M. chelonae in farmed sturgeons was only a secondary event related to its presence in a stressful rearing environment and subsequent to a dystrophic calcinosis occurred in previously damaged tissues. PMID:24423126

  5. Monitoring the effects of storage in caviar from farmed Acipenser transmontanus using chemical, SEM, and NMR methods.

    PubMed

    Gussoni, Maristella; Greco, Fulvia; Vezzoli, Alessandra; Paleari, Maria Antonietta; Moretti, Vittorio Maria; Beretta, Giuseppe; Caprino, Fabio; Lanza, Barbara; Zetta, Lucia

    2006-09-06

    The effects of storage at 4 degrees C on the quantity and quality of chemical components in the caviar from farmed Acipenser transmontanus have been analyzed by SEM, chemical methods, and NMR and MRI techniques. Particular attention has been focused on the lipid components, the distribution and mobility of which were strongly affected by the storage time. MRI and relaxation data indicated that lipids are endowed with two different mobility regimes, one slow (short T1) and one fast (long T1), both lengthening with the storage time. Chemical analysis assessed a total fat content that remained practically unchanged and a constant fatty acid composition during the total storage time. The combination of the two methods allowed one (a) to suppose that a mechanism of lipid hydrolysis (faster in unsalted than in salted eggs) is still occurring during storage of caviar at 4 degrees C for up to approximately 4 months and (b) to exclude that an intensive oxidative process is active in the same storage period.

  6. Effects of multiple collections on spermatozoa quality of Persian sturgeon, Acipenser persicus: motility, density and seminal plasma composition.

    PubMed

    Aramli, M S; Kalbassi, M R; Gharibi, M R

    2015-02-01

    In this study, we investigated the effects of multiple collections of sperm on the endangered Persian sturgeon, Acipenser persicus, in terms of a number of sperm functional parameters (percentage of motile spermatozoa, total time period of motility and sperm concentration) as well as on the ionic composition, protein concentration and osmolality of seminal plasma. Semen samples were collected from 12 induced male fish in three experimental groups that had been injected intramuscularly with LHRH-A2, at dosages of 5 μg/kg body weight, at a number of time regimes: at 12 h, 17 h and 24 h after spawning induction (1); at 24, 29 and 34 h after spawning induction (2); and at 36, 41 and 46 h after spawning induction (3). The percentage of motile spermatozoa and the period of sperm motility decreased significantly (p < 0.05) after the second and third collections. The concentration of spermatozoa decreased after the third collection, but this decline was not significant. No significant effect of multiple collections on protein concentration and ionic content (with exception of the Cl(-) ion) of seminal plasma was observed. In all experimental groups, a moderate impact of sequential collection on the osmolality (p < 0.05) of seminal plasma was observed. This study provides new data on the effects of multiple collections on spermatological characteristics in the Persian sturgeon. Our results confirm that sequential stripping after the third collections has a negative effect on a number of functional parameters associated with sperm.

  7. Rethinking the influence of hydroelectric development on gene flow in a long-lived fish, the Lake Sturgeon Acipenser fulvescens

    PubMed Central

    McDougall, Craig A.; Welsh, Amy B.; Gosselin, Thierry; Anderson, W. Gary; Nelson, Patrick A.

    2017-01-01

    Many hydroelectric dams have been in place for 50 - >100 years, which for most fish species means that enough generations have passed for fragmentation induced divergence to have accumulated. However, for long-lived species such as Lake Sturgeon, Acipenser fulvescens, it should be possible to discriminate between historical population structuring and contemporary gene flow and improve the broader understanding of anthropogenic influence. On the Winnipeg River, Manitoba, two hypotheses were tested: 1) Measureable quantities of former reservoir dwelling Lake Sturgeon now reside downstream of the Slave Falls Generating Station, and 2) genetically differentiated populations of Lake Sturgeon occur upstream and downstream, a result of historical structuring. Genetic methods based on ten microsatellite markers were employed, and simulations were conducted to provide context. With regards to contemporary upstream to downstream contributions, the inclusion of length-at-age data proved informative. Both pairwise relatedness and Bayesian clustering analysis substantiated that fast-growing outliers, apparently entrained after residing in the upstream reservoir for several years, accounted for ~15% of the Lake Sturgeon 525–750 mm fork length captured downstream. With regards to historical structuring, upstream and downstream populations were found to be differentiated (FST = 0.011, and 0.013–0.014 when fast-growing outliers were excluded), and heterozygosity metrics were higher for downstream versus upstream juveniles. Historical asymmetric (downstream) gene flow in the vicinity of the generating station was the most logical explanation for the observed genetic structuring. In this section of the Winnipeg River, construction of a major dam does not appear to have fragmented a previously panmictic Lake Sturgeon population, but alterations to habitat may be influencing upstream to downstream contributions in unexpected ways. PMID:28329005

  8. Using drift nets to capture early life stages and monitor spawning of the yangtze river chinese sturgeon (Acipenser sinensis)

    USGS Publications Warehouse

    Wei, Q.W.; Kynard, B.; Yang, D.G.; Chen, X.H.; Du, H.; Shen, L.; Zhang, H.

    2009-01-01

    A sampling system for capturing sturgeon eggs using a D-shaped bottom anchored drift net was used to capture early life stages (ELS) of Chinese sturgeon, Acipenser sinensis, and monitor annual spawning success at Yichang on the Yangtze River, 1996-2004, before and just after the Three Gorges Dam began operation. Captured were 96 875 ELS (early life stages: eggs, yolk-sac larvae = eleuthero embryos, and larvae); most were eggs and only 2477 were yolk-sac larvae. Most ELS were captured in the main river channel and inside the bend at the Yichang spawning reach. Yolk-sac larvae were captured for a maximum of 3 days after hatching began, indicating quick dispersal downstream. The back-calculated day of egg fertilization over the eight years indicated a maximum spawning window of 23 days (20 October-10 November). Spawning in all years was restricted temporally, occurred mostly at night and during one or two spawning periods, each lasting several days. The brief temporal spawning window may reduce egg predation by opportunistic predators by flooding the river bottom with millions of eggs. During 1996-2002, the percentage of fertilized eggs in an annual 20-egg sample was between 63.5 to 94.1%; however, in 2003 the percentage fertilized was only 23.8%. This sudden decline may be related to the altered environmental conditions at Yichang caused by operation of the Three Gorges Dam. Further studies are needed to monitor spawning and changes in egg fertilization in this threatened population. ?? 2009 Blackwell Verlag GmbH.

  9. Sperm characteristics and androgens in Acipenser ruthenus after induction of spermiation by carp pituitary extract or GnRHa implants.

    PubMed

    Alavi, Sayyed Mohammad Hadi; Hatef, Azadeh; Mylonas, Constantinos C; Gela, David; Papadaki, Maria; Rodina, Marek; Kašpar, Vojtech; Pšenička, Martin; Podhorec, Peter; Linhart, Otomar

    2012-12-01

    Spermiation and changes in androgen (testosterone, T and 11-ketotestosterone, 11-KT) levels were studied in sterlet (Acipenser ruthenus) treated with GnRH agonist implants (DAla(6)-Pro(9)-LHRHa) at 25 and 75 μg kg(-1) b.w. and compared with those males treated with 4 mg kg(-1) b.w. of carp pituitary extract (CPE) and 3 pellets of Ovopel kg(-1) b.w., which contains DAla(6)-Pro(9)NEt-mGnRH and metoclopramide. Sperm quality (sperm mass, spermatozoa concentration and sperm motility and velocity) was evaluated 24, 48 and 72 h after hormonal treatments. Males did not release sperm in the control group injected with physiological solution, while sperm could not be collected 7 days after treatments in all hormonally treated groups. Spermiation rates were 100 % in the CPE and Ovopel groups and 25-50 % in the GnRHa-treated groups. Sperm production was significantly lower in the GnRHa-treated groups than in the CPE and Ovopel groups and decreased 72 h after hormonal treatment. Sperm motility and velocity were higher in the Ovopel and GnRHa (75 μg) groups compared to the CPE and GnRHa (25 μg) groups and decreased 72 h after hormonal treatment. Androgens were only affected in spermiating males and changed in the Ovopel and GnRHa (75 μg) after hormonal treatment. Significant correlations were observed between sperm production, sperm motility and sperm velocity, but not androgens. The present study suggests involvement of dopamine in sturgeon spawning. Additionally, better sperm quality observed in the Ovopel group and particularly sperm motility in the GnRHa (75 μg) suggests enhancement of sperm quality in sturgeon treated with GnRHa. Therefore, further study is needed to induce fully spermiation using GnRHa implants in combination with a dopamine inhibitor.

  10. Rethinking the influence of hydroelectric development on gene flow in a long-lived fish, the Lake Sturgeon Acipenser fulvescens.

    PubMed

    McDougall, Craig A; Welsh, Amy B; Gosselin, Thierry; Anderson, W Gary; Nelson, Patrick A

    2017-01-01

    Many hydroelectric dams have been in place for 50 - >100 years, which for most fish species means that enough generations have passed for fragmentation induced divergence to have accumulated. However, for long-lived species such as Lake Sturgeon, Acipenser fulvescens, it should be possible to discriminate between historical population structuring and contemporary gene flow and improve the broader understanding of anthropogenic influence. On the Winnipeg River, Manitoba, two hypotheses were tested: 1) Measureable quantities of former reservoir dwelling Lake Sturgeon now reside downstream of the Slave Falls Generating Station, and 2) genetically differentiated populations of Lake Sturgeon occur upstream and downstream, a result of historical structuring. Genetic methods based on ten microsatellite markers were employed, and simulations were conducted to provide context. With regards to contemporary upstream to downstream contributions, the inclusion of length-at-age data proved informative. Both pairwise relatedness and Bayesian clustering analysis substantiated that fast-growing outliers, apparently entrained after residing in the upstream reservoir for several years, accounted for ~15% of the Lake Sturgeon 525-750 mm fork length captured downstream. With regards to historical structuring, upstream and downstream populations were found to be differentiated (FST = 0.011, and 0.013-0.014 when fast-growing outliers were excluded), and heterozygosity metrics were higher for downstream versus upstream juveniles. Historical asymmetric (downstream) gene flow in the vicinity of the generating station was the most logical explanation for the observed genetic structuring. In this section of the Winnipeg River, construction of a major dam does not appear to have fragmented a previously panmictic Lake Sturgeon population, but alterations to habitat may be influencing upstream to downstream contributions in unexpected ways.

  11. Gender and gonadal maturity stage identification of captive Chinese sturgeon, Acipenser sinensis, using ultrasound imagery and sex steroids.

    PubMed

    Du, Hao; Zhang, Xiaoyan; Leng, Xiaoqian; Zhang, Shuhuan; Luo, Jiang; Liu, Zhigang; Qiao, Xingmei; Kynard, Boyd; Wei, Qiwei

    2016-08-03

    Long lifespan and late maturation make it difficult to establish gamete maturity and breeding age of captive endangered Chinese sturgeon, Acipenser sinensis. This greatly handicaps timely breeding and future conservation stocking efforts. We used ultrasound imagery and sex steroids to determine the gender and gonadal maturity stage of captive Chinese sturgeon (age, 10-17years old). The echogenicity of the reproductive organs and the respective morphology of the gonads were described and two quantitative parameters po (proportion of the ovary to the entire reproductive organs) and d (thickness of the reproductive organs) were measured to characterize sex and maturity stage of Chinese sturgeon. Females were accordingly placed fish into several categories: FII (FII(-), FII, FII(+)), FIII (FIII, FIII(+)) and FIV (FIV, FIV(+)) and FVI and males as MII, MIII, MIV, MV and MVI. The accuracy of gender and maturity stage determination provided by ultrasonographic methods was 72.7% for FII(-) ovary (n=11) and 76.2% for MII testis (n=42). Accuracy of sex and maturity determination using only serum sex steroid of testosterone (T) and estradiol-17β (E2) was low (58-73%, depending on maturity stage). However, when the two methods were used together, accuracy increased sharply, especially for immature (II stage) females. In summary, of 151 Chinese sturgeon, whose sex and maturity stage were independently confirmed, 88.1% (n=133), 62.9% (n=95), and 96.7% (n=146) were successfully sexed and staged using ultrasound, sex steroids, or both methods, respectively. The results provide reliable non-invasive techniques for determining sex and gonadal maturation of captive Chinese sturgeon. These methods can track individual gonad characteristics over multi-year reproductive cycles, which will assist captive broodstock management, artificial reproduction, and future conservation stocking.

  12. Evaluation of liver histopathology and EROD activity in St. Lawrence lake sturgeon (Acipenser fulvescens) in comparison with a reference population

    SciTech Connect

    Rousseaux, C.G. ||; Branchaud, A.; Spear, P.A.

    1995-05-01

    In an attempt to evaluate the effects of contaminants on the lake sturgeon Acipenser fulvescens, fish were netted from two sites: Riviere des Prairies, confluent with the St. Lawrence River near Montreal, and a reference site on the upper reaches of the Ottawa River in the La Verendrye Park. Livers of fish collected from the Riviere des Prairies were difficult to homogenize, and they left behind strands of what appeared to be connective tissue. Suspecting hepatic fibrosis, the authors decided to evaluate the livers for histopathologic changes. Nineteen adult lake sturgeon (eleven male and eight female) were examined. Following fixation, routine processing, sectioning, and staining with hematoxylin and eosin, microscopic evaluation revealed the following: Sections taken from livers of fish from the Riviere des Prairies site showed excessive fat accumulation and often severe chronic-active cholangiohepatitis. Bile duct proliferation (p < 0.0001), periportal fibrosis (p < 0.0001), inflammation (p < 0.001), and fat accumulation (p < 0.05) were more pronounced in the fish from the Riviere des Prairies site. Melano-macrophage centers appeared to be both paler and gave the appearance of fewer numbers (p < 0.01). Livers from lake sturgeon taken from the reference site had a more normal appearance. The EROD levels were also significantly induced in these fish (reference 3.39 {+-} 0.57; Riviere des Prairies site 8.21 {+-} 0.87 pmol/mg protein/min; p < 0.0005). The EROD levels positively correlated with bile duct proliferation (r{sup 2} = 0.44; p = 0.001) and periportal fibrosis (r{sup 2} = 0.41; p = 0.002). Despite the statistical associations above, the authors cannot categorically state that contaminants are the sole cause of the lesions seen.

  13. Effects of Dietary Garlic Powder on Growth, Feed Utilization and Whole Body Composition Changes in Fingerling Sterlet Sturgeon, Acipenser ruthenus

    PubMed Central

    Lee, Dong-Hoon; Lim, Seong-Ryul; Han, Jung-Jo; Lee, Sang-Woo; Ra, Chang-Six; Kim, Jeong-Dae

    2014-01-01

    A 12 week growth study was carried out to investigate the supplemental effects of dietary garlic powder (GP) on growth, feed utilization and whole body composition changes of fingerling sterlet sturgeon Acipenser ruthenus (averaging weight, 5.5 g). Following a 24-h fasting, 540 fish were randomly distributed to each of 18 tanks (30 fish/tank) under a semi-recirculation freshwater system. The GP of 0.5% (GP0.5), 1% (GP1), 1.5% (GP1.5), 2% (GP2) and 3% (GP3) was added to the control diet (GP0) containing 43% protein and 16% lipid. After the feeding trial, weight gain (WG) of fish fed GP1.5, GP2 and GP3 were significantly higher (p<0.05) than those of fish fed GP0, GP0.5 and GP1. Feed efficiency and specific growth rate (SGR) showed a similar trend to WG. Protein efficiency ratio of fish fed GP1.5, GP2, and GP3 were significantly higher (p<0.05) than those of fish groups fed the other diets. A significant difference (p<0.05) was found in whole body composition (moisture, crude protein, crude lipid, ash, and fiber) of fish at the end of the experiment. Significantly higher (p<0.05) protein and lipid retention efficiencies (PRE and LRE) were also found in GP1.5, GP2, and GP3 groups. Broken-line regression model analysis and second order polynomial regression model analysis relation on the basis of SGR and WG indicated that the dietary optimal GP level could be greater than 1.77% and 1.79%, but less than 2.95% and 3.18% in fingerling sterlet sturgeon. The present study suggested that dietary GP for fingerling sterlet sturgeon could positively affect growth performance and protein retention. PMID:25178374

  14. Ontogeny of salinity tolerance and evidence for seawater-entry preparation in juvenile green sturgeon, Acipenser medirostris.

    PubMed

    Allen, Peter J; McEnroe, Maryann; Forostyan, Tetyana; Cole, Stephanie; Nicholl, Mary M; Hodge, Brian; Cech, Joseph J

    2011-12-01

    We measured the ontogeny of salinity tolerance and the preparatory hypo-osmoregulatory physiological changes for seawater entry in green sturgeon (Acipenser medirostris), an anadromous species occurring along the Pacific Coast of North America. Salinity tolerance was measured every 2 weeks starting in 40-day post-hatch (dph) juveniles and was repeated until 100% survival at 34‰ was achieved. Fish were subjected to step increases in salinity (5‰ 12 h(-1)) that culminated in a 72-h exposure to a target salinity, and treatment groups (0, 15, 20, 25, 30, 34‰; and abrupt exposure to 34‰) were adjusted as fish developed. After 100% survival was achieved (134 dph), a second experiment tested two sizes of fish for 28-day seawater (33‰) tolerance, and gill and gastrointestinal tract tissues were sampled. Their salinity tolerance increased and plasma osmolality decreased with increasing size and age, and electron microscopy revealed three types of mitochondria-rich cells: one in fresh water and two in seawater. In addition, fish held on a natural photoperiod in fresh water at 19°C showed peaks in cortisol, thyroid hormones and gill and pyloric ceca Na(+), K(+)-ATPase activities at body sizes associated with seawater tolerance. Therefore, salinity tolerance in green sturgeon increases during ontogeny (e.g., as these juveniles may move down estuaries to the ocean) with increases in body size. Also, physiological and morphological changes associated with seawater readiness increased in freshwater-reared juveniles and peaked at their seawater-tolerant ages and body sizes. Their seawater-ready body size also matched that described for swimming performance decreases, presumably associated with downstream movements. Therefore, juvenile green sturgeon develop structures and physiological changes appropriate for seawater entry while growing in fresh water, indicating that hypo-osmoregulatory changes may proceed by multiple routes in sturgeons.

  15. Differentiation of the cardiac outflow tract components in alevins of the sturgeon Acipenser naccarii (Osteichthyes, Acipenseriformes): implications for heart evolution.

    PubMed

    Guerrero, Alejandro; Icardo, José M; Durán, Ana C; Gallego, Alejandro; Domezain, Alberto; Colvee, Elvira; Sans-Coma, Valentín

    2004-05-01

    Previous work showed that in the adult sturgeon an intrapericardial, nonmyocardial segment is interposed between the conus arteriosus of the heart and the ventral aorta. The present report illustrates the ontogeny of this intermediate segment in Acipenser naccarii. The sample studied consisted of 178 alevins between 1 and 24 days posthatching. They were examined using light and electron microscopy. Our observations indicate that the entire cardiac outflow tract displays a myocardial character during early development. Between the fourth and sixth days posthatching, the distal portion of the cardiac outflow tract undergoes a phenotypical transition, from a myocardial to a smooth muscle-like phenotype. The length of this region with regard to the whole outflow tract increases only moderately during subsequent developmental stages, becoming more and more cellularized. The cells soon organize into a pattern that resembles that of the arterial wall. Elastin appears at this site by the seventh day posthatching. Therefore, two distinct components, proximal and distal, can be recognized from the fourth day posthatching in the cardiac outflow tract of A. naccarii. The proximal component is the conus arteriosus, characterized by its myocardial nature and the presence of endocardial cushions. The distal component transforms into the intrapericardial, nonmyocardial segment mentioned above, which is unequivocally of cardiac origin. We propose to designate this segment the "bulbus arteriosus" because it is morphogenetically equivalent to the bulbus arteriosus of teleosts. The present findings, together with data from the literature, point to the possibility that cells from the cardiac neural crest are involved in the phenotypical transition that takes place at the distal portion of the cardiac outflow tract, resulting in the appearance of the bulbus arteriosus. Moreover, they suggest that the cardiac outflow tract came to be formed by a bulbus arteriosus and a conus arteriosus

  16. Novel technique for visualizing primordial germ cells in sturgeons (Acipenser ruthenus, A. gueldenstaedtii, A. baerii, and Huso huso).

    PubMed

    Saito, Taiju; Psenicka, Martin

    2015-10-01

    Primordial germ cells (PGCs) are the origin of all germ cells in developing embryos. In the sturgeon embryo, PGCs develop from the vegetal hemisphere, which mainly acts as an extraembryonic source of nutrition. Current methods for studying sturgeon PGCs require either killing the fish or using costly and time-consuming histological procedures. Here, we demonstrate that visualization of sterlet (Acipenser ruthenus>) PGCs in vivo is feasible by simply labeling the vegetal hemisphere with fluorescein isothiocyanate (FITC)-dextran. We injected FITC-dextrans, with molecular weights varying between 10 000 and 2 000 000, into the vegetal pole of 1- to 4-cell stage embryos. At the neurula to tail-bud developmental stages, FITC-positive PGC-like cells appeared ventrally around the developing tail bud in the experimental group that received a high-molecular-weight FITC-dextran. The highest average number of FITC-positive PGC-like cells was observed in embryos injected with FITC-dextran having a molecular weight of 500 000 (FD-500). The pattern of migration of the labeled cells was identical to that of PGCs, clearly indicating that the FITC-positive PGC-like cells were PGCs. Labeled vegetal cells, except for the PGCs, were digested and excreted before the embryos starting feeding. FITC-labeled PGCs were observed in the developing gonads of fish for at least 3 mo after injection. We also found that FD-500 could be used to visualize PGCs in other sturgeon species. To the best of our knowledge, this report is the first to demonstrate in any animal species that PGCs can be visualized in vivo for a long period by the injection of a simple reagent.

  17. Ontogenetic behavior and dispersal of Sacramento River white sturgeon, Acipenser transmontanus, with a note on body color

    USGS Publications Warehouse

    Kynard, B.; Parker, E.

    2005-01-01

    We studied Sacramento River white sturgeon, Acipenser transmontanus, in the laboratory to develop a conceptual model of ontogenetic behavior and provide insight into probable behavior of wild sturgeon. After hatching, free embryos initiated a low intensity, brief downstream dispersal during which fish swam near the bottom and were photonegative. The weak, short dispersal style and behavior of white sturgeon free embryos contrasts greatly with the intense, long dispersal style and behavior (photopositive and swimming far above the bottom) of dispersing free embryos of other sturgeon species. If spawned eggs are concentrated within a few kilometers downstream of a spawning site, the adaptive significance of the free embryo dispersal is likely to move fish away from the egg deposition site to avoid predation and reduce fish density prior to feeding. Larvae foraged on the open bottom, swam <1 m above the bottom, aggregated, but did not disperse. Early juveniles initiated a strong dispersal with fish strongly vigorously swimming downstream. Duration of the juvenile dispersal is unknown, but the strong swimming likely disperses fish many kilometers. Recruitment failure in white sturgeon populations may be a mis-match between the innate fish dispersal and post-dispersal rearing habitat, which is now highly altered by damming and reservoirs. Sacramento River white sturgeon has a two-step downstream dispersal by the free embryo and juvenile life intervals. Diel activity of all life intervals peaked at night, whether fish were dispersing or foraging. Nocturnal behavior is likely a response to predation, which occurs during both activities. An intense black-tail body color was present on foraging larvae, but was weak or absent on the two life intervals that disperse. Black-tail color may be an adaptation for avoiding predation, signaling among aggregated larvae, or both, but not for dispersal. ?? Springer 2005.

  18. A new species of nucleo-cytoplasmic large DNA virus (NCLDV) associated with mortalities in Manitoba lake sturgeon Acipenser fulvescens.

    PubMed

    Clouthier, Sharon C; Vanwalleghem, Elissa; Copeland, Shelagh; Klassen, Cheryl; Hobbs, Gary; Nielsen, Ole; Anderson, Eric D

    2013-02-28

    A newly discovered virus, Namao virus, associated with morbidity and mortality, was detected among juvenile lake sturgeon Acipenser fulvescens being propagated by a conservation stocking program for this endangered species in Manitoba, Canada. The outbreaks resulted in cumulative mortalities of 62 to 99.6% among progeny of wild Winnipeg River or Nelson River lake sturgeon and occurred at 2 geographically separate facilities. Namao virus was detected in almost 94% of the moribund or dead lake sturgeon according to a conventional polymerase chain reaction (cPCR) test that is based upon amplification of a 219 bp fragment of the virus major capsid protein (MCP). The virus itself was large (242 to 282 nm) and icosahedral-shaped with 2 capsids and a condensed bar-shaped core. It was found in virus factories within the host cell cytoplasm and displayed a tropism for the integument. Namao virus caused cellular changes characterized by enlarged eosinophilic epithelial cells in the gills and skin. Samples suspected of containing Namao virus did not have cytopathic effects on primary lake sturgeon or established white sturgeon cell lines. However, viral nucleic acid was detected in the former after prolonged incubation periods. Using primers designed from conserved regions of the MCP from NCLDVs, an estimated 95 to 96% of the Namao virus MCP open reading frame was captured. Phylogenetic analysis using the MCP of Namao virus and 27 other NCLDVs suggested that Namao virus and white sturgeon iridovirus share a common evolutionary past and might be members of the family Mimiviridae or a new, as yet unrecognized, virus family.

  19. The effects of temperature and body size on immunological development and responsiveness in juvenile shortnose sturgeon (Acipenser brevirostrum).

    PubMed

    Gradil, Ana M; Wright, Glenda M; Speare, David J; Wadowska, Dorota W; Purcell, Sara; Fast, Mark D

    2014-10-01

    Sturgeon are an important evolutionary taxa of which little is known regarding their responses to environmental factors. Water temperature strongly influences growth in fish; however, its effect on sturgeon immune responses is unknown. The objective of this study was to assess how 2 different temperatures affect immune responses in shortnose sturgeon (Acipenser brevirostrum) relevant immune organs such as the meningeal myeloid tissue, spleen, thymus and skin. These responses were studied in 2 different sizes of same age juvenile sturgeon kept at either 11 °C or 20 °C (4 treatment groups), before and after exposure to an ectoparasitic copepod (Dichelesthium oblongum). Based on a differential cell count, temperature was found to strongly influence immune cell production in the meningeal myeloid tissue, regardless of the fish sizes considered. Morphometric analysis of splenic white pulp showed a transient response to temperature. There were no differences between the groups in the morphometric analysis of thymus size. Splenic IRF-1 and IRF-2 had similar expression profiles, significantly higher in fish kept at 20 °C for the first 6 weeks of the study but not by 14 weeks. In the skin, IRF-1 was significantly higher in the fish kept at 11 °C over the first 6 weeks of the study. IRF-2 had a similar profile but there were no differences between the groups by the end of the trial. In conclusion, higher water temperatures (up to 20 °C) may have beneficial effects in maximizing growth and improving immunological capacity, regardless of the fish sizes considered in this study.

  20. Effects of subchronic exposure of early life stages of white sturgeon (Acipenser transmontanus) to copper, cadmium, and zinc.

    PubMed

    Vardy, David W; Tompsett, Amber R; Sigurdson, Jacinda L; Doering, Jon A; Zhang, Xiaowei; Giesy, John P; Hecker, Markus

    2011-11-01

    Populations of sturgeon (Acipenseridae) are declining in many places in the world because of several potential factors, including overharvesting, habitat alteration, and pollution. In North America, populations of the white sturgeon (Acipenser transmontanus) have been experiencing poor annual recruitment in major river systems for more than three decades. Metal pollution has been hypothesized as a potential contributing factor to the poor recruitment in some of the water bodies. In general, little is known about the toxicity of metals such as Cu, Cd, and Zn to white sturgeon and their potential influence on survival of embryos and juveniles. The present study was conducted to establish baseline toxicity data for the subchronic exposure of early life stages of white sturgeon to Cu, Cd, and Zn that can be used in metal-related risk assessments. Embryos, larvae, and fry were exposed to increasing concentrations of dissolved Cu, Cd, or Zn for 66 d using laboratory-based flow-through exposure systems. Hatching success was greater than 79% for all controls, and no significant differences were observed among treatment groups or between treatments and controls. Chronic lethal concentrations at which 20% mortality occurred (LC20s) for Cd (1.5 µg/L), Cu (5.5 µg/L), and Zn (112 µg/L) obtained for white sturgeon in the present study were comparable to those of sensitive salmonid species. Based on LC20 values for 19 or 58 d posthatch white sturgeon, the United States national ambient water quality criteria and the Canadian water quality guidelines for the protection of aquatic life that have been established for Cd, Cu, and Zn protect white sturgeon early life stages.

  1. Effect of anaesthetics MS-222 and clove oil on blood biochemical parameters of juvenile Siberian sturgeon (Acipenser baerii)

    USGS Publications Warehouse

    Feng, G.; Zhuang, P.; Zhang, L.; Kynard, B.; Shi, X.; Duan, M.; Liu, J.; Huang, X.

    2011-01-01

    The effects of MS-222 and clove oil on blood biochemical parameters of juvenile Siberian sturgeon (Acipenser baerii) were studied. MS-222 caused higher glucose (GLU) concentrations in anaesthetic test groups than for the control group. Triglyceride (TGL) concentrations of fish in the 140 and 160mgL-1 groups were also significantly higher than those of other groups. Alanine aminotransferase (ALT) activity in the 140mgL-1 group was significantly higher than the level in 80, 100 and 120mgL-1 groups. Aspartate aminotransferase (AST) activity in the 140mgL-1 group was significantly higher than those in the 100 and 120mgL-1 groups. Levels of total protein (TP), cholesterol (CHOL) and alkaline phosphatase (ALP) in anaesthetic test groups were not significantly influenced by MS-222. Clove oil did not have significant effects on levels of GLU, TP, CHOL, ALT and ALP. TGL concentration of fish exposed to 180mgL-1 clove oil was significantly higher than those of the rest anaesthetic groups. AST activities of fish exposed to 120, 150 and 180mgL-1 were significantly higher than those of 60 and 90mgL-1. Overall, TGL and AST could be potentially used as indicators of anaesthetic stress for juvenile Siberian sturgeon. Based on blood biochemical parameters, the appropriate anaesthetic concentrations of MS-222 and clove oil were 80-120mgL-1 and 60-90mgL-1, respectively. Clove oil was a promising alternative to MS-222. ?? 2011 Blackwell Verlag, Berlin.

  2. Expression and phylogeny of candidate genes for sex differentiation in a primitive fish species, the Siberian sturgeon, Acipenser baerii.

    PubMed

    Berbejillo, Julio; Martinez-Bengochea, Anabel; Bedo, Gabriela; Brunet, Frédéric; Volff, Jean-Nicolas; Vizziano-Cantonnet, Denise

    2012-08-01

    The molecular mechanisms underlying testis differentiation in basal actinopterygian fish remains poorly understood. The sex differentiation period was investigated in the Siberian sturgeon, Acipenser baerii, by expression profiling of Sertoli cell transcription factors (dmrt1, sox9) that control testis differentiation in vertebrates; Leydig cell factors (cyp17a1, star) affecting androgen production; the androgen receptor (ar); a growth factor controlling testis development (igf1); and a gene coding for a gonadotropin hormone (lh). Two genes were characterised for the first time in the Siberian sturgeon (dmrt1, cyp17a1), while the others came from public databases. Sturgeon gonad development is very slow, with a late sexual differentiation time during their juvenile stage, and are still immature at 3 years of age. Immature fish showed a sex-dimorphic pattern; all the genes studied displayed a higher expression level in male gonads. We took advantage of the presence of juvenile fish with pre- and post-differentiated gonads (16 and 18 months old) to characterise them at the molecular level. The post-differentiated fish displayed a sex dimorphism of gene expression in their gonads for all genes studied, with the exception of sox9. The trends in undifferentiated fish lead us to propose that sturgeons undergoing male differentiation express high levels of Sertoli cell factors (dmrt1, sox9) and of genes involved in the production and receptivity of androgens (cyp17a1, star and ar) together with lh. Expression profiles and phylogenetic studies suggest that these genes are potential regulators of testis development in the Siberian sturgeon.

  3. Isolation of Yersinia ruckeri strain H01 from farm-raised Amur Sturgeon Acipenser schrencki in China.

    PubMed

    Shaowu, Li; Di, Wang; Hongbai, Liu; Tongyan, Lu

    2013-03-01

    Yersinia ruckeri is the causative agent of enteric redmouth disease or yersiniosis, which affects salmonids and several other species of fish. However, there are no reports on the characteristics and pathogenicity of Y. ruckeri isolated from farm-raised Amur Sturgeon Acipenser schrencki. Here, we isolated and characterized Y. ruckeri strain H01 from the diseased Amur Sturgeon in China. The phenotypic and genotypic characteristics of Y. ruckeri were observed, and its virulence was tested by examining experimentally infected sturgeons. Examination of the flagellar morphology of Y. ruckeri by transmission electron microscopy showed five to eight peritrichous flagella located on the cell body. Actively dividing cells with an obvious cell membrane were approximately 0.64 μm in diameter and between 1.7 and 2.5 μm in length. The dose that was lethal to 50% of the test fish after intraperitoneal injection was determined to be 7.2×10(6) CFU, and Y. ruckeri could be reisolated from the liver and kidneys of infected sturgeon. Antimicrobial susceptibility tests showed that H01 was susceptible to 10 antimicrobial agents. Part of the 16S rRNA sequences (563 base pair) was amplified and sequenced to study the genotypic characterization in Y. ruckeri (GenBank accession number JQ657818). The phylogenetic tree revealed H01 was clustered together with Y. ruckeri strains. Together, this study describes the isolation, characterization, and phenotypic-genotypic analysis of a Y. ruckeri strain isolated from farm-raised Amur Sturgeon. The results discovered may provide some theoretical basis for the prevention and control of yersiniosis in Amur Sturgeon.

  4. Mitochondrial proton leak rates in the slow, oxidative myotomal muscle and liver of the endothermic shortfin mako shark (Isurus oxyrinchus) and the ectothermic blue shark (Prionace glauca) and leopard shark (Triakis semifasciata).

    PubMed

    Duong, Cindy A; Sepulveda, Chugey A; Graham, Jeffrey B; Dickson, Kathryn A

    2006-07-01

    Mitochondrial proton leak was assessed as a potential heat source in the slow, oxidative (red) locomotor muscle and liver of the shortfin mako shark (Isurus oxyrinchus), a regional endotherm that maintains the temperature of both tissues elevated above ambient seawater temperature. We hypothesized that basal proton leak rates in red muscle and liver mitochondria of the endothermic shortfin mako shark would be greater than those of the ectothermic blue shark (Prionace glauca) and leopard shark (Triakis semifasciata). Respiration rate and membrane potential in isolated mitochondria were measured simultaneously at 20 degrees C using a Clark-type oxygen electrode and a lipophilic probe (triphenylmethylphosphonium, TPMP(+)). Succinate-stimulated respiration was titrated with inhibitors of the electron transport chain, and the non-linear relationship between respiration rate and membrane potential was quantified. Mitochondrial densities of both tissues were measured by applying the point-contact method to electron micrographs so that proton leak activity of the entire tissue could be assessed. In all three shark species, proton leak occurred at a higher rate in red muscle mitochondria than in liver mitochondria. For each tissue, the proton leak curves of the three species overlapped and, at a membrane potential of 160 mV, mitochondrial proton leak rate (nmol H(+) min(-1) mg(-1) protein) did not differ significantly between the endothermic and ectothermic sharks. This finding indicates that red muscle and liver mitochondria of the shortfin mako shark are not specialized for thermogenesis by having a higher proton conductance. However, mako mitochondria did have higher succinate-stimulated respiration rates and membrane potentials than those of the two ectothermic sharks. This means that under in vivo conditions mitochondrial proton leak rates may be higher in the mako than in the ectothermic species, due to greater electron transport activity and a larger proton gradient

  5. Physiological stress response, reflex impairment and delayed mortality of white sturgeon Acipenser transmontanus exposed to simulated fisheries stressors

    PubMed Central

    McLean, Montana F.; Hanson, Kyle C.; Cooke, Steven J.; Hinch, Scott G.; Patterson, David A.; Nettles, Taylor L.; Litvak, Matt K.; Crossin, Glenn T.

    2016-01-01

    White sturgeon (Acipenser transmontanus) are the largest freshwater fish in North America and a species exposed to widespread fishing pressure. Despite the growing interest in recreational fishing for white sturgeon, little is known about the sublethal and lethal impacts of angling on released sturgeon. In summer (July 2014, mean water temperature 15.3°C) and winter (February 2015, mean water temperature 6.6°C), captive white sturgeon (n = 48) were exposed to a combination of exercise and air exposure as a method of simulating an angling event. After the stressor, sturgeon were assessed for a physiological stress response, and reflex impairments were quantified to determine overall fish vitality (i.e. capacity for survival). A physiological stress response occurred in all sturgeon exposed to a fishing-related stressor, with the magnitude of the response correlated with the duration of the stressor. Moreover, the stress from exercise was more pronounced in summer, leading to higher reflex impairment scores (mean ± SEM, 0.44 ± 0.07 and 0.25 ± 0.05 in summer and winter, respectively). Reflex impairment was also correlated with lactate concentrations (e.g. physiological stress measures related to exhaustive exercise; r = 0.53) and recovery time (r = 0.76). Two mortalities occurred >24 h after the cessation of treatment in the summer. Given that natural habitats for white sturgeon can reach much higher temperatures than those presented in our study, we caution the use of this mortality estimate for a summer season, because latent mortality could be much higher when temperatures exceed 16°C. This is the first experiment investigating the physiological disturbance and reflex impairment of capture and release at two temperatures on subadult/adult white sturgeon, and the results suggest that future research needs to examine the longer term and fitness consequences of extended play and air exposure times, because these are largely unknown for wild populations

  6. Effects of diazinon on adaptation to sea-water by the endangered Persian sturgeon, Acipenser persicus, fingerlings.

    PubMed

    Hajirezaee, Saeed; Mirvaghefi, Ali Reza; Farahmand, Hamid; Agh, Naser

    2016-11-01

    To replenish the depleting populations of sturgeon fishes especially Persian sturgeon, Acipenser persicus in the Caspian Sea, millions of Persian sturgeon fingerlings are farmed through artificial propagation and released into the Iranian river estuaries annually. Fish osmoregulation is a vital physiological process that can be affected during the release. Many Iranian river estuaries are under the influence of pesticides originating from farming activities that may affect osmoregulation. In this study, Persian sturgeon fingerlings were exposed to sublethal concentrations (0, 0.18, 0.54, 0.9mgL(-)(1)) of diazinon for 96h (short-term trial) and 12 days (long-term trial) in fresh water (FW) and then fish were exposed in brackish water (BW) for 24h. After 96h and 12 days of exposure in FW, the lower levels of plasma triidothyronine (T3), thyroxine (T4), Na(+), Cl(-), K(+), gill Na(+)/K(+)- ATPase activity and number of chloride cells were observed in exposed fish (0.54 and 0.9mgL(-)(1) diazinon) compared to control group and 0.18mgL(-)(1) diazinon treatment. Also, higher levels of plasma cortisol (except 0.18mgL(-)(1) diazinon treatment in long-term trial) were observed in diazinon exposed fish compared to control group. However, gill Na(+)/K(+)-ATPase activity and the number of chloride cells were higher in fingerlings exposed to diazinon compared than control. When fish were exposed in BW for 24h, the following changes occurred: (a) in short-term trial: increases in cortisol and Cl(-) levels (0.54mgL(-)(1) diazinon ), Na(+) (0.9mgL(-)(1) diazinon ) and gill Na(+)/K(+)-ATPase activity (0.18mgL(-)(1) diazinon ). In control group, cortisol, T4, Na(+), gill Na(+)/K(+)-ATPase activity and the number of chloride cells increased significantly. (b) In long-term trial: increases in K(+) levels in fish exposed to 0.9mgL(-)(1) diazinon, Na+ in all diazinon concentrations and decreases in chloride cells number in fish exposed to 0.18mgL(-)(1) diazinon. In control group

  7. Maintaining tissue selenium species distribution as a potential defense mechanism against methylmercury toxicity in juvenile white sturgeon (Acipenser transmontanus).

    PubMed

    Huang, Susie Shih-Yin; Hung, Silas S O; Chan, Hing Man

    2014-11-01

    Selenium (Se) has been shown to antagonize mercury (Hg) toxicity. We have previously demonstrated that orally intubated selenomethionine (SeMet) and methylmercury (MeHg) reduced tissue Se accumulation, as well as blood and kidney Hg concentrations in juvenile white sturgeon (Acipenser transmontanus). However, the form of Se accumulated is not known. In this study, three organoseleniums: selenocysteine (Sec), Se-methyl-selenocysteine (MSeCys), and SeMet and two inorganic Se species: selenate and selenite were determined and quantified in the blood at different post-intubation periods (12, 24, 48h) and in the muscle, liver, and kidneys at 48h in white sturgeon orally intubated with a single dose of control (carrier), SeMet (500μg Se/kg body weight; BW), MeHg (850μg Hg/kg BW), and both (Se+Hg; at 500μg Se/kg and 850μg Hg/kg BW). When only SeMet was intubated, the accumulative/unmodified pathway took precedent in the blood, white muscle, liver, and kidneys. In the presence of MeHg, however, active metabolic transformation and de novo synthesis of biologically active Se forms are seen in the liver and kidneys, as indicated by a gradual increase in blood Sec:SeMet ratios and Se metabolites. In the white muscle, mobilization of endogenous Se storage by MeHg is supported by the absence of tissue SeMet and detectable levels of blood SeMet. In contrast, co-intubation with SeMet increased muscle SeMet. The high levels of unknown Se metabolites and detectable levels of selenite in the kidney reflect its role as the major excretory organ for Se. Selenium metabolism is highly regulated in the kidneys, as Se speciation was not affected by MeHg or by its co-intubation with SeMet. In the Se+Hg group, the proportion of SeMet in the liver has decreased to nearly 1/8th of that of the SeMet only group, resulting in a more similar selenocompound distribution profile to that of the MeHg only group. This is likely due to the increased need for Se metabolites necessary for Me

  8. Physiological stress response, reflex impairment and delayed mortality of white sturgeon Acipenser transmontanus exposed to simulated fisheries stressors.

    PubMed

    McLean, Montana F; Hanson, Kyle C; Cooke, Steven J; Hinch, Scott G; Patterson, David A; Nettles, Taylor L; Litvak, Matt K; Crossin, Glenn T

    2016-01-01

    White sturgeon (Acipenser transmontanus) are the largest freshwater fish in North America and a species exposed to widespread fishing pressure. Despite the growing interest in recreational fishing for white sturgeon, little is known about the sublethal and lethal impacts of angling on released sturgeon. In summer (July 2014, mean water temperature 15.3°C) and winter (February 2015, mean water temperature 6.6°C), captive white sturgeon (n = 48) were exposed to a combination of exercise and air exposure as a method of simulating an angling event. After the stressor, sturgeon were assessed for a physiological stress response, and reflex impairments were quantified to determine overall fish vitality (i.e. capacity for survival). A physiological stress response occurred in all sturgeon exposed to a fishing-related stressor, with the magnitude of the response correlated with the duration of the stressor. Moreover, the stress from exercise was more pronounced in summer, leading to higher reflex impairment scores (mean ± SEM, 0.44 ± 0.07 and 0.25 ± 0.05 in summer and winter, respectively). Reflex impairment was also correlated with lactate concentrations (e.g. physiological stress measures related to exhaustive exercise; r = 0.53) and recovery time (r = 0.76). Two mortalities occurred >24 h after the cessation of treatment in the summer. Given that natural habitats for white sturgeon can reach much higher temperatures than those presented in our study, we caution the use of this mortality estimate for a summer season, because latent mortality could be much higher when temperatures exceed 16°C. This is the first experiment investigating the physiological disturbance and reflex impairment of capture and release at two temperatures on subadult/adult white sturgeon, and the results suggest that future research needs to examine the longer term and fitness consequences of extended play and air exposure times, because these are largely unknown for wild populations.

  9. Temporal trends of polychlorinated biphenyls, polybrominated diphenyl ethers, and perfluorinated compounds in Chinese sturgeon (Acipenser sinensis) eggs (1984-2008).

    PubMed

    Jianxian, Sun; Hui, Peng; Jianying, Hu

    2015-02-03

    Because investigation on the temporal trends of persistent halogenated compounds (PHCs) is necessary to predict their future impacts on the environment and human health and evaluate the effectiveness of regulations on their production and usage, it is of concern to investigate annual temporal trends of PHCs in biota samples. This study examined the temporal trends of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and perfluorinated compounds (PFCs) in Chinese sturgeon (Acipenser sinensis) eggs over a period of 25 years (1984-2008), and 62 PCBs (19.2-1030 ng/g dw for total PCBs), 16 PBDEs (4.7-572 ng/g dw for total PBDEs), and 14 PFCs (26-46 ng/g dw for total PFCs) were detected. Although a decreasing temporal trend was observed for total PCBs with annual reduction rate of 3.4% (ρ = 0.005), a clear break point was observed around 1991, indicating their continuing emission in the 1980s in China. All major PBDEs showed increasing temporal trends, with annual change rates at 3.5-10.2% over the 25 years, but a sharp decreasing trend was observed after 2006, indicating a rapid response to the banning of PBDE usage in China in 2004. The greatest annual rate of increase was observed for BDE-28 (10.2%) followed by BDE-100 (7.7%), which would be due to metabolism input from higher brominated PBDEs. Significantly increasing temporal trends were observed for all PFCs, and the annual rates of increase were 7.9% and 5.9% for total perfluorinated carboxylic acids and perfluorooctanesulfonate (PFOS), respectively. A peak concentration for PFOS was observed in 1989, which may be related to the import history of PFCs in China. The present study is the first report of systematic temporal trends of PHCs in biota samples from China and shows that regulatory policy is needed to reduce their potential health and ecological risk in China considering the increasing temporal trends of PBDEs and PFCs.

  10. Vertebral Development and Ossification in the Siberian Sturgeon (Acipenser Baerii), with New Insights on Bone Histology and Ultrastructure of Vertebral Elements and Scutes.

    PubMed

    Leprévost, Amandine; AzaÏs, Thierry; Trichet, Michael; Sire, Jean-Yves

    2017-03-01

    In order to improve our knowledge on the vertebral development, structure and mineralization in Acipenseriformes, we undertook a study in a growth series of reared Siberian sturgeons (Acipenser baerii) using in toto clear and stain specimens, histological and ultrastructural observations, X-ray micro-tomography, and solid state NMR analyses. Scutes were also studied to compare the tissue structure and mineralization of endoskeletal and dermal skeletal elements. This study completes and clarifies previous investigations on vertebral development and architecture in sturgeons, and brings original data on the structure of (i) the perichondral bone that is progressively deposited around the vertebral elements during ontogeny, (ii) the typical cartilage composing these elements, and (iii) the scutes. In addition we provide data on the mineralization process, on the nature of the bone mineral phase, and on the growth dynamics of the vertebral elements. Anat Rec, 300:437-449, 2017. © 2016 Wiley Periodicals, Inc.

  11. Lake sturgeon Acipenser fulvescens and shovelnose sturgeon Scaphirhynchus platorynchus environmental life history revealed using pectoral fin-ray microchemistry: implications for interjurisdictional conservation through fishery closure zones.

    PubMed

    Phelps, Q E; Hupfeld, R N; Whitledge, G W

    2017-02-01

    This study inferred that the majority of shovelnose sturgeon Scaphirhynchus platorynchus captured in the upper Mississippi River probably originated from locations outside the upper Mississippi River (Missouri River, middle Mississippi River); whereas, lake sturgeon Acipenser fulvescens exhibit infrequent movement outside of the upper Mississippi River, but may move throughout these interconnected large rivers at various life stages. By using pectoral fin-ray microchemistry (a non-lethal alternative to using otoliths), it is suggest that interjurisdictional cooperation will probably be needed to ensure sustainability of the S. platorynchus commercial fishery and the success of A. fulvescens reintroduction in the upper Mississippi River. Additionally, fin-ray microchemistry can provide invaluable data to make informed management decisions regarding large river fishes, that cross jurisdictional boundaries or that move outside of closure zones, without causing further mortality to compromised fish populations (e.g. threatened and endangered species).

  12. Effect of dietary macronutrient proportion on intermediate metabolism and oxidative status in sturgeon (Acipenser naccarii) and trout (Oncorhynchus mykiss): comparative study.

    PubMed

    Furné, M; García-Gallego, M; Hidalgo, M C; Sanz, A

    2016-08-01

    Three isoenergetic diets varying the proportion of dietary energy supplied by each of the macronutrients (carbohydrate, lipid, or protein) were delivered, to farmed sturgeon (Acipenser naccarii) and trout (Oncorhynchus mykiss), to test the possible effects on the intermediate metabolism and oxidative status in liver, white muscle, and heart. In trout, there is an adaptive metabolic response to an increase in lipids and carbohydrates in the diet. However, this does not happen in the sturgeon. These differences may be due to different dietary habits of both species. In terms of oxidative status, only the liver displayed oxidative stress in both species, showing an increase in the lipid peroxidation and antioxidant enzyme activities after feeding with the high-lipid and high-protein diet.

  13. Ontogenetic behavior and migration of Dabry's sturgeon, Acipenser dabryanus, from the Yangtze River, with notes on body color and development rate

    USGS Publications Warehouse

    Kynard, B.; Zhuang, P.; Zhang, T.; Zhang, L.

    2003-01-01

    We conducted laboratory experiments with Dabry's sturgeon, Acipenser dabryanus, from the upper Yangtze River to develop a conceptual model of early behavior. We daily observed fish from day-0 (embryo, first life interval after hatching) to day-30 feeding larva for preference of bright habitat and cover, swimming distance above the bottom, up- and down-stream movement, and diel activity. Hatchling to day-12 embryos and days 13-24 larvae were similar for ontogenetic behavior, i.e., neither initiated a dispersal migration, both swam within 15 cm of the bottom, both preferred bright habitat, and neither strongly preferred cover or open habitat. Embryos and larvae were weakly active day and night. Days 72-76 juveniles had a weak nocturnal downstream migration, indicating wild juveniles disperse from a spawning site. In other sturgeon species yet studied representing three genera on three continents, Dabry's sturgeon is the first that does not disperse as an embryo or larva. Development of Dabry's sturgeon is slow, requiring more cumulative temperature degree days per millimeter of larvae TL than is required for other sturgeons to develop into larvae. Thus, a dispersal migration that diverts energy from development may not be adaptive. The available information suggests the initial dispersal of early life intervals is likely done by females, which spawn in a dispersed spawning style, not the usual aggregated spawning style. Juvenile migrants had a black body and tail with a light line along the lateral scutes. The color of juvenile migrants shows that a dark body and tail is characteristic of Acipenser that migrate downstream as larvae or juveniles.

  14. Defining winter trophic habitat of juvenile Gulf Sturgeon in the Suwannee and Apalachicola rivermouth estuaries, acoustic telemetry investigations

    USGS Publications Warehouse

    Sulak, K.J.; Randall, M.T.; Edwards, R.E.; Summers, T.M.; Luke, K.E.; Smith, W.T.; Norem, A.D.; Harden, William M.; Lukens, R.H.; Parauka, F.; Bolden, S.; Lehnert, R.

    2009-01-01

    Three automated listening post-telemetry studies were undertaken in the Suwannee and Apalachicola estuaries to gain knowledge of habitats use by juvenile Gulf Sturgeons (Acipenser oxyrinchus desotoi) on winter feeding grounds. A simple and reliable method for external attachment of small acoustic tags to the dorsal fin base was developed using shrink-tubing. Suspending receivers on masts below anchored buoys improved reception and facilitated downloading; a detection range of 500–2500 m was realized. In the Apalachicola estuary, juvenile GS stayed in shallow water (< 2 m) within the estuarine transition zone all winter in the vicinity of the Apalachicola River mouth. Juvenile GS high-use areas did not coincide with high density benthic macrofauna areas from the most recent (1999) benthos survey. In the Suwannee estuary, juveniles ranged widely and individually throughout oligohaline to mesohaline subareas of the estuary, preferentially using mesohaline subareas seaward of Suwannee Reef (52% of acoustic detections). The river mouth subarea was important only in early and late winter, during the times of adult Gulf Sturgeon migrations (41% of detections). Preferred winter feeding subareas coincided spatially with known areas of dense macrofaunal benthos concentrations. Following a dramatic drop in air and water temperatures, juvenile GS left the river mouth and estuary, subsequently being detected 8 km offshore in polyhaline open Gulf of Mexico waters, before returning to the estuary. Cold-event offshore excursions demonstrate that they can tolerate full-salinity polyhaline waters in the open Gulf of Mexico, for at least several days at a time. For juvenile sturgeons, the stress and metabolic cost of enduring high salinity (Jarvis et al., 2001; McKenzie et al., 2001; Singer and Ballantyne, 2002) for short periods in deep offshore waters seems adaptively advantageous relative to the risk of cold-event mortality in shallow inshore waters of lower salinity. Thus

  15. Sensitivity of lake sturgeon (Acipenser fulvescens) early life stages to 2,3,7,8-tetrachlorodibenzo-P-dioxin and 3,3',4,4',5-pentachlorobiphenyl.

    PubMed

    Tillitt, Donald E; Buckler, Justin A; Nicks, Diane K; Candrl, James S; Claunch, Rachel A; Gale, Robert W; Puglis, Holly J; Little, Edward E; Linbo, Tiffany L; Baker, Mary

    2017-04-01

    The aquatic food web of the Great Lakes has been contaminated with polychlorinated biphenyls (PCBs) since the mid-20th century. Threats of PCB exposures to long-lived species of fish, such as lake sturgeon (Acipenser fulvescens), have been uncertain because of a lack of information on the relative sensitivity of the species. The objective of the present study was to evaluate the sensitivity of early-life stage lake sturgeon to 3,3',4,4',5-pentachlorobiphenyl (PCB-126) or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure. Mortality, growth, morphological and tissue pathologies, swimming performance, and activity levels were used as assessment endpoints. Pericardial and yolk sac edema, tubular heart, yolk sac hemorrhaging, and small size were the most commonly observed pathologies in both TCDD and PCB-126 exposures, beginning as early as 4 d postfertilization, with many of these pathologies occurring in a dose-dependent manner. Median lethal doses for PCB-126 and TCDD in lake sturgeon were 5.4 ng/g egg (95% confidence interval, 3.9-7.4 ng/g egg) and 0.61 ng/g egg (0.47-0.82 ng/g egg), respectively. The resulting relative potency factor for PCB-126 (0.11) was greater than the World Health Organization estimate for fish (toxic equivalency factor = 0.005), suggesting that current risk assessments may underestimate PCB toxicity toward lake sturgeon. Swimming activity and endurance were reduced in lake sturgeon survivors from the median lethal doses at 60 d postfertilization. Threshold and median toxicity values indicate that lake sturgeon, like other Acipenser species, are more sensitive to PCB and TCDD than the other genus of sturgeon, Scaphirhynchus, found in North America. Indeed, lake sturgeon populations in the Great Lakes and elsewhere are susceptible to PCB/TCDD-induced developmental toxicity in embryos and reductions in swimming performance. Environ Toxicol Chem 2017;36:988-998. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This

  16. The description and histopathology of Leptorhynchoides polycristatus n. sp. (Acanthocephala: Rhadinorhynchidae) from sturgeons, Acipenser spp. (Actinopterygii: Acipenseridae) in the Caspian Sea, Iran, with emendation of the generic diagnosis.

    PubMed

    Amin, Omar M; Heckmann, Richard A; Halajian, Ali; El-Naggar, Atif M; Tavakol, Sareh

    2013-11-01

    Of the three known species of Leptorhynchoides Kostylew 1924, two are reported from North American fishes: Leptorhynchoides aphredoderi Buckner and Buckner 1976 and Leptorhynchoides thecatus (Linton 1891) Kostylew 1924. The third species, Leptorhynchoides plagicephalus (Westrumb 1821) Kostylew 1924, is commonly found in the Caspian and Black Sea from at least four species of sturgeons including Acipenser stellatus Pallas 1771 and the Acipenser nudiventris Lovetzsky 1828 from which Leptorhynchoides polycristatus n. sp. was found. No taxonomic work has been reported for L. plagicephalus for the last 90 years. L. polycristatus n. sp. can be readily confused with L. plagicephalus because of many superficial similarities. Such similarities include the general shape of the trunk, proboscis, and organ systems. However, L. polycristatus is clearly distinguished from the other three species primarily by having (1) 19-20 proboscis hooks per row; (2) the shortest hooks are anterior and the longest at the middle; the opposite is true in L. plagicephalus; (3) with a cuticular collar enveloping the base of the proboscis hooks; (4) the surface of its proboscis hooks is ribbed; (5) with a broad collar of multiple rectangular cuticular crests encircling the anterior end of the trunk; this is the only member of Leptorhynchoides with such a structure; (6) with many large ovoid uninucleated cells in the subcuticular layer of the trunk; (7) with paired glandular clusters near the male reproductive opening and of suction cup-like sensory structures on the bursa; (8) with dorsoventral ligament across the vagina; (9) cement glands are in a cluster of eight arranged in two horizontal tiers of four glands each; (10) with female gonopore near terminal; (11) with structures interpreted as possible microtriches on the surface of the trunk; (12) and with thinner eggs. L. polycristatus caused extensive histopathological damage to host intestinal layers. The armed proboscis invades and attaches

  17. Characterization of the contents and histology of the gastrointestinal tracts of White Sturgeon (Acipenser transmontanus) captured from Upper Lake Roosevelt, Washington, October 2008

    USGS Publications Warehouse

    Parsley, Michael J.; van der Leeuw, Bjorn K.; Elliott, Diane G.

    2010-01-01

    The gastrointestinal tracts of 37 juvenile white sturgeon (Acipenser transmontanus) captured from the upper part of Lake Roosevelt during October 2008, were examined to identify prey taxa and to determine if the fish were consuming smelter slag along with other sediments. Histological examination of the gastrointestinal tract tissues and comparison with similar tissues from hatchery-reared fish also was performed. The contents of the gastro-intestinal tracts (guts) indicated that white sturgeon were actively foraging on various benthic invertebrates and the diet was quite diverse, with more than 50 percent of the fish feeding on five or more different taxa. Slag was present in 76 percent of the guts examined. Although not all guts contained slag particles, larger fish tended to have greater amounts of slag in their guts. Histology of the gut tissues showed the presence of a chronic inflammatory response, and the severity of the response had a significant positive correlation (P = 0.01) with fish length and weight suggesting that the inflammation represented a response to long-term exposure to one or more stressors. However, additional work is needed to determine if the physical or chemical properties of slag contributed to this response.

  18. Simultaneous extraction and cleanup of high-lipid organs from white sturgeon (Acipenser transmontanus) for multiple legacy and emerging organic contaminants using QuEChERS sample preparation.

    PubMed

    Morrison, Shane A; Sieve, Kristal K; Ratajczak, Robert E; Bringolf, Robert B; Belden, Jason B

    2016-01-01

    The objective of this research was to utilize the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) method to extract a broad range of persistent organic pollutants from sturgeon organs (liver and gonad) as indicators of exposure. The analyte list was prioritized to include carcinogenic polyaromatic hydrocarbons (PAHs), the most commonly occurring polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs), persistent bioaccumulative and toxic chemicals (PBTs), and emergent contaminants of concern (ECCs) as indicators of human sewage exposure. White sturgeon (Acipenser transmontanus) were selected for this study to support a larger ecotoxicological study to monitor contaminants as an assessment of fish health. Organ tissues contained high lipid content with percentages of 15% and 34% for liver and gonad, respectively. Overall recoveries from fortified sturgeon tissues were high, 71-98% for PAHs, 60-107% for PBDEs and PCBs, 86-107% for PBT chemicals, and 88-107% for ECCs with the exception of octinoxate (28%) from liver tissues. Analyte recovery trends decreased as analyte lipophilicity and molecular weight increased. These recoveries demonstrate that extraction using QuEChERS can be used for screening of the most common bioaccumulating organic compounds in high lipid fish tissue using a single extraction and analysis.

  19. Verifying success of artificial spawning reefs in the St. Clair-Detroit River System for lake sturgeon (Acipenser fulvescens Rafinesque, 1817)

    USGS Publications Warehouse

    Bouckaert, Emliy K.; Auer, Nancy A.; Roseman, Edward F.; James Boase,

    2014-01-01

    Lake sturgeon (Acipenser fulvescens) were historically abundant in the St. Clair – Detroit River System (SCDRS), a 160 km river/channel network. In the SCDRS, lake sturgeon populations have been negatively affected by the loss/degradation of natural spawning habitat. To address habitat loss for lake sturgeon and other species, efforts are underway to restore spawning substrate by constructing artificial reefs. The main objective of this study was to conduct post-construction monitoring of lake sturgeon egg deposition and larval emergence near two of these artificial reefs: Fighting Island Reef (FIR) in the Detroit River, and Middle Channel Reef in the St. Clair River. An additional site in the St. Clair River where lake sturgeon spawn on a coal clinker bed was also investigated. From 2010 to 2012, viable eggs and larvae were collected from all of these reefs, indicating that conditions are suitable for egg deposition, incubation, and larval emergence. In the St. Clair River, the results indicate the likelihood of other spawning sites upstream of these artificial reef sites.

  20. Adaptive alterations on gill Na⁺, K⁺-ATPase activity and mitochondrion-rich cells of juvenile Acipenser sinensis acclimated to brackish water.

    PubMed

    Zhao, Feng; Wu, Beibei; Yang, Gang; Zhang, Tao; Zhuang, Ping

    2016-04-01

    Understanding the physiological changes and osmoregulatory strategy is critical for anadromous species to adapt to large changes between freshwater and marine environments. In this study, juvenile Chinese sturgeon (Acipenser sinensis) were acclimated for 2 months to freshwater (FW, c. 0‰) and brackish water (BW, 15‰). Blood was assessed for changes in osmolality and ions. Gill tissue was assayed for Na(+), K(+)-ATPase (NKA) activity and immunohistochemical analysis on mitochondria-rich cells (MRCs). Serum osmolality and ions concentrations (Na(+), Cl(-) and K(+)) examined, except K(+), increased significantly in those specimens adapted to BW. However, the variations were within the range of effective hyperosmotic adaptation. The specific activity of gill NKA of juveniles adapted to BW was significantly higher (c. 1.6 times) than that of fish adapted to FW. MRCs were mainly presented in the interlamellar region of the filament and at the base of the lamella in either FW- or BW-acclimated individuals. In BW, the number and size of MRCs on filaments greatly increased. However, there was no significant difference in the number and size of the MRCs at the lamella region. Results show that juvenile Chinese sturgeon keep osmotic homeostasis in hyperosmotic environments by increasing gill NKA activity and MRCs' size and number, which is similar to other sturgeons and euryhaline teleosts.

  1. Ancient fish and recent invaders: white sturgeon Acipenser transmontanus diet response to invasive-species-mediated changes in a benthic prey assemblage

    USGS Publications Warehouse

    Zeug, Steven C; Brodsky, Annie; Kogut, Nina; Stewart, Robin; Merz, Joe

    2014-01-01

    Invasive organisms can have significant impacts on native species, and the San Francisco Estuary (SFE), California, USA, is one of the world's most invaded estuaries. Decline of native white sturgeon Acipenser transmontanus abundance in the SFE has been acknowledged, but underlying mechanisms are poorly understood. Invasion by the overbite clam Potamocorbula amurensis has drastically altered the SFE benthic prey community, yet little is known about how this change has affected sturgeon diets. We investigated changes in the diet of white sturgeon following the overbite clam invasion and subsequent shift in the SFE benthic prey assemblage. Gut content analysis was used to compare white sturgeon prey composition and importance between the pre- and post-invasion periods. Additionally, stable isotope analysis was employed to estimate the assimilation of prey items to sturgeon biomass. Overbite clams dominated diets in the post-invasion period, accounting for 82 to 93% of total volume. Stable isotope analysis confirmed the importance of this prey item, although their assimilated contribution to sturgeon biomass was estimated to be less (70 to 83%) than gut contents indicated. The frequency of fish in white sturgeon guts increased in the post-invasion period, and isotope analysis indicated relatively large contributions of fish to sturgeon biomass (3.7 to 19%). The trophic adaptability of white sturgeon has allowed them to exploit this new prey source (overbite clam). Future conservation and restoration efforts must consider a potentially destabilized food web given the large importance of a single prey item.

  2. Effects of chlorpyrifos on in vitro sex steroid production and thyroid follicular development in adult and larval Lake Sturgeon, Acipenser fulvescens.

    PubMed

    Brandt, Catherine; Burnett, Duncan C; Arcinas, Liane; Palace, Vince; Gary Anderson, W

    2015-08-01

    Chlorpyrifos is a widely used organophosphate pesticide that has previously been shown to enter waterways in biologically relevant concentrations and has the potential to disrupt both thyroid hormone and sex steroid biosynthesis in vertebrates. Because gonadal maturation and larval development in Lake Sturgeon, Acipenser fulvescens, potentially coincide with the application of chlorpyrifos we examined the effects of chlorpyrifos on both thyroid follicular development in larval Lake Sturgeon, and sex hormone synthesis in adult Lake Sturgeon. For the first time, the present study reports steroidogenesis from testicular and ovarian tissue in Lake Sturgeon using an established in vitro bioassay. Furthermore, incubating gonad tissue with 5, 500 or 2000ngmL(-1) chlorpyrifos revealed an inhibitory effect on testosterone synthesis in both testicular (control, 40.29pgmg(-1) tissue wet weight(-1)h(-1) compared to experimental, 21.84pgmg(-1) tissue wet weight(-1)h(-1)) and ovarian (control, 33.83pgmg(-1) tissue wet weight(-1)h(-1) compared to experimental, 15.19pgmg(-1) tissue wet weight(-1)h(-1)) tissue. In a second series of experiments, larval Lake Sturgeon were exposed to equivalent concentrations of chlorpyrifos as above for 10days (d) between hatch and the onset of exogenous feeding. Larvae from each treatment group were raised until 67days post hatch (dph) and growth rates were compared alongside key indicators of thyroid follicle growth. Chlorpyrifos treatment had no effect on the measured indicators of thyroid follicular development.

  3. Steroidogenic acute regulatory protein in white sturgeon (Acipenser transmontanus): cDNA cloning, sites of expression and transcript abundance in corticosteroidogenic tissue after an acute stressor.

    PubMed

    Kusakabe, Makoto; Zuccarelli, Micah D; Nakamura, Ikumi; Young, Graham

    2009-06-01

    The white sturgeon, Acipenser transmontanus, is a primitive bony fish that is recognized as an important emerging species for aquaculture. However, many aspects of its stress and reproductive physiology remain unclear. These processes are controlled by various steroid hormones. In order to investigate the regulation of steroidogenesis associated with acute stress in sturgeon, a cDNA-encoding steroidogenic acute regulatory protein (StAR) was isolated from white sturgeon. The putative amino acid sequence of sturgeon StAR shares high homology (over 60%) with other vertebrates. Phylogenetic analysis grouped sturgeon StAR within Actinopterygii, but it was clearly segregated from teleost StARs. RT-PCR analysis revealed that transcripts were most abundant in yellow corpuscles found throughout the kidney and weaker signals were detected in gonad and kidney. Very weak signals were also detected in brain and spleen by quantitative real-time PCR. In situ hybridization revealed that StAR is expressed in the cells of yellow corpuscles. No significant changes in StAR gene expression were detected in response to an acute handling stress. These results suggest that StAR is highly conserved throughout vertebrates, but the expression of the functional protein during the stress response may be partially regulated post-transcriptionally.

  4. Case report: concurrent herpesviral and presumptive iridoviral infection associated with disease in cultured shortnose sturgeon, Acipenser brevirostrum (L.), from the Atlantic coast of Canada.

    PubMed

    LaPatra, S E; Groff, J M; Keith, I; Hogans, W E; Groman, D

    2014-02-01

    Approximately 8 weeks after a chlorine insult associated with the city water supply, shortnose sturgeon, Acipenser brevirostrum (L.), from one group presented with small (3-4 mm) irregular foci of cutaneous pallor that involved the dorsocranial integument with progressive ulceration of the nascent lesions. Various bacterial organisms were isolated from the cutaneous lesions, but not from the internal viscera. Histologically, the nuclei of the intralesional and perilesional epidermal cells often exhibited margination of the chromatin that resulted in a homogenous, pale, amphophilic, tinctorial quality of the nucleoplasm consistent with a herpesvirus infection. In addition, rare lamellar epithelial cells were prominently enlarged due to an abundant, dense, basophilic cytoplasm characteristic of an iridovirus infection. Inoculation of cutaneous lesion and kidney, spleen, liver sample pools from affected shortnose sturgeon onto white sturgeon spleen (WSS-2) cell line induced cytopathic effect characterized by syncytia formation. Ultrastructural analysis of infected WSS-2 cells revealed viral particles with a characteristic herpesvirus morphology. Intranuclear hexagonal capsids had a diameter of 95-108 nm, and enveloped particles present in the cytoplasm of infected cells had a diameter of 176-196 nm. This is the first report of a herpesvirus and a possible iridovirus-like infection in shortnose sturgeon.

  5. Long-term effects of intraperitoneal injection of estradiol-17β on the growth and physiology of juvenile stellate sturgeon Acipenser stellatus.

    PubMed

    Falahatkar, Bahram; Poursaeid, Samaneh; Meknatkhah, Bahman; Khara, Hossein; Efatpanah, Iraj

    2014-04-01

    Juvenile stellate sturgeon Acipenser stellatus were intraperitoneally injected with estradiol-17β (E2; 0 and 5 mg/kg fish) to investigate the possibility of sex reversal and also determine the changes in biochemical parameters. Five-month-old fish (40.9 ± 1.1 g) were injected every 3-week interval during a 190-day trial. At the termination of the experiment, final weight and other growth parameters including weight gain and specific growth rate, hepatosomatic and viscerosomatic indices were not affected by repetitive injection of E2. Hematological features of E2-treated fish showed significant reductions in number of red blood cells, hemoglobin concentration, hematocrit value and mean corpuscular hemoglobin (P < 0.05), but no significant changes were observed in number of white blood cells, mean corpuscular volume and mean corpuscular hemoglobin concentration (P > 0.05). Calcium, phosphorus, glucose, triacylglycerol, cholesterol, total protein and estradiol concentrations were significantly increased in fish injected with E2 (P < 0.001). Plasma progesterone and testosterone levels were noticeably lower in fish injected with 5 mg/kg E2 rather than the control fish (P < 0.001). Histological observations of gonads showed that all fish injected with 5 mg/kg E2 apparently feminized, while 66.6 % of the control group was female. These results revealed that the injection of E2 is an effective method for feminization of stellate sturgeon without having significant inhibitory effects on growth and survival.

  6. Effects of feeding on thermoregulatory behaviours and gut blood flow in white sturgeon (Acipenser transmontanus) using biotelemetry in combination with standard techniques.

    PubMed

    Gräns, A; Olsson, C; Pitsillides, K; Nelson, H E; Cech, J J; Axelsson, M

    2010-09-15

    The effects of thermoregulatory behaviours on gut blood flow in white sturgeon Acipenser transmontanus before and after feeding was studied using a blood flow biotelemetry system in combination with a temperature preference chamber. This is the first study to look at cardiovascular responses to feeding in white sturgeon, and also the first time behavioural tests in fish have been combined with recordings of cardiac output, heart rate, cardiac stroke volume and gut blood flow. The results showed strong correlations between gut blood flow and temperature choice after feeding (R(2)=0.88+/-0.03, 6-8 h postprandially and R(2)=0.89+/-0.04, 8-10 h postprandially) but not prior to feeding (R(2)=0.11+/-0.05). Feeding did not affect the actual temperature preference (18.4+/-0.7 degrees C before feeding, 18.1+/-0.7 degrees C, 6-8 h postprandially and 17.5+/-0.5 degrees C, 8-10 h postprandially). Fish instrumented with a blood flow biotelemetry device, and allowed to move freely in the water, had a significantly lower resting heart rate (37.3+/-0.26 beats min(-1)) compared with the control group that was traditionally instrumented with transit-time blood flow probes and kept in a confined area in accordance with the standard procedure (43.2+/-2.1 beats min(-1)). This study shows, for the first time in fish, the correlation between body temperature and gut blood flow during behavioural thermoregulation.

  7. Linking Oxidative Stress and Magnitude of Compensatory Responses with Life-Stage Specific Differences in Sensitivity of White Sturgeon (Acipenser transmontanus) to Copper or Cadmium.

    PubMed

    Tang, Song; Doering, Jon A; Sun, Jianxian; Beitel, Shawn C; Shekh, Kamran; Patterson, Sarah; Crawford, Sarah; Giesy, John P; Wiseman, Steve B; Hecker, Markus

    2016-09-06

    Sensitivity of white sturgeon (Acipenser transmontanus) to copper (Cu) or cadmium (Cd) has been shown to significantly differ as a function of life-stage. This study investigated oxidative stress, metal homeostasis, and associated compensatory responses as potential mechanisms of this sensitivity pattern in three early life-stages. Sturgeon were most sensitive to Cu at 15 days post hatch (dph), which was accompanied by a significant increase in lipid peroxidation (LPO). Genes involved with amelioration of oxidative stress were significantly less inducible at this stage than in older, less sensitive fry. At 48 dph, acute lethality of sturgeon exposed to Cd was greatest and body LPO was significantly induced by 3.5-fold at 5 μg Cd/L. Moreover, there was a small but significant increase in antioxidative responses. At 139 dph, sturgeon were most tolerant to Cu and Cd and accumulation of these metals was least. Also, expression of metallothionein (MT) and apoptotic genes were greatest while expression of metal transporters was reduced and concentration of LPO was not different from controls. Our results suggest that life-stage specific sensitivity of white sturgeon to metals is complex, encompassing differences in the ability to mount compensatory responses important for metal homeostasis and combating oxidative stress and concomitant damages.

  8. Reintroduction of Lake Sturgeon (Acipenser fulvescens) into the St. Regis River, NY: Post-release assessment of habitat use and growth

    USGS Publications Warehouse

    Dittman, Dawn E.; Chalupnicki, Marc A.; Johnson, James H.; Snyder, James

    2015-01-01

    One of the depleted endemic fish species of the Great Lakes, Acipenser fulvescens (Lake Sturgeon), has been the target of extensive conservation efforts. One strategy is reintroduction into historically productive waters. The St. Regis River, NY, represents one such adaptive-management effort, with shared management between New York and the St. Regis Mohawk Tribe. Between 1998 and 2004, a total of 4977 young-of-year Lake Sturgeon were released. Adaptive management requires intermediate progress metrics. During 2004 and 2005, we measured growth, habitat use, and survivorship metrics of the released fish. We captured a total of 95 individuals of all stocked ages. Year-class minimal-survival rates ranged from 0.19–2.1%. The size-at-age and length/biomass relationships were comparable to those reported for juveniles in other Great Lakes waters. These intermediate assessment metrics can provide feedback to resource managers who make restoration-program decisions on a much shorter time-scale than the time-frame in which the ultimate goal of a self-sustaining population can be attained.

  9. Balbiani cytoplasm in oocytes of a primitive fish, the sturgeon Acipenser gueldenstaedtii, and its potential homology to the Balbiani body (mitochondrial cloud) of Xenopus laevis oocytes.

    PubMed

    Zelazowska, Monika; Kilarski, Wincenty; Bilinski, Szczepan M; Podder, Daniel D; Kloc, Malgorzata

    2007-07-01

    The oocytes of many organisms, including frogs and fish, contain a distinct cytoplasmic organelle called the Balbiani body. Because of the scarcity of published information and the tremendous variability in the appearance, ultrastructure, and composition of Balbiani bodies between species, the function of the Balbiani body and its inter-species homology remain a mystery. In Xenopus laevis, the Balbiani body is known to play a role in transporting germ cell determinants and localized RNAs to the oocyte vegetal cortex. In fish, however, the molecular composition of the Balbiani body has not been studied to date, and its function remains completely unknown. We have studied the ultrastructure and molecular composition of previtellogenic oocytes of the sturgeon, Acipenser gueldenstaedtii, by using electron microscopy, in situ hybridization, and immunostaining. We have found that sturgeon oocytes contain two distinct zones of cytoplasm: homogeneous (organelle-free) and granular (organelle-rich). We have also found that the granular ooplasm, which we term the Balbiani cytoplasm, shares important homologies, in both ultrastructure and molecular composition, with Xenopus Balbiani bodies.

  10. Characterization of Na(+) transport to gain insight into the mechanism of acid-base and ion regulation in white sturgeon (Acipenser transmontanus).

    PubMed

    Shartau, Ryan B; Brix, Kevin V; Brauner, Colin J

    2017-02-01

    Freshwater fish actively take up ions via specific transporters to counter diffusive losses to their hypotonic environment. While much is known about the specific mechanisms employed by teleosts, almost nothing is known about the basal fishes, such as white sturgeon (Acipenser transmontanus) which may offer insight into the evolution of osmo- and ionoregulation in fishes. We investigated Na(+) uptake in juvenile white sturgeon in the presence and absence of transporter inhibitors. We found that sturgeon acclimated to 100μmoll(-1) Na(+) have Na(+) uptake kinetics typical of teleosts and that a Na(+)/H(+) exchanger (NHE) is the predominant transporter for Na(+) uptake. White sturgeon are tolerant to hypercarbia-induced respiratory acidoses and recover blood pH (pHe) at 1.5kPa PCO2 but not at higher PCO2 (6kPa PCO2) where they preferentially regulate intracellular pH (pHi). It was hypothesized that during exposure to hypercarbia Na(+) uptake would increase at CO2 tensions at which fish were capable of pHe regulation but decrease at higher tensions when they were preferentially regulating pHi. We found that Na(+) uptake did not increase at 1.5kPa PCO2, but at 6kPa PCO2 Na(+) uptake was reduced by 95% while low water pH equivalent to 6kPa PCO2 reduced Na(+) uptake by 71%. Lastly, we measured net acid flux during hypercarbia, which indicates that net acid flux is not associated with Na(+) uptake. These findings indicate Na(+) uptake in sturgeon is not different from freshwater teleosts but is sensitive to hypercarbia and is not associated with pHe compensation during hypercarbia.

  11. Chronic sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to cadmium, copper, lead, or zinc in laboratory water-only exposures

    USGS Publications Warehouse

    Wang, Ning; Ingersoll, Christopher G.; Dorman, Rebecca A.; Brumbaugh, William G.; Mebane, Christopher A.; Kunz, James L.; Hardesty, Douglas K.

    2014-01-01

    Chronic toxicity of cadmium, copper, lead, or zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) was evaluated in water-only exposures started with newly hatched larvae or approximately 1-mo-old juveniles. The 20% effect concentration (EC20) for cadmium from the sturgeon tests was higher than the EC20 from the trout tests, whereas the EC20 for copper, lead, or zinc for the sturgeon were lower than those EC20s for the trout. When the EC20s from the present study were included in compiled toxicity databases for all freshwater species, species mean chronic value for white sturgeon was in a relatively low percentile of the species sensitivity distribution for copper (9th percentile) and in the middle percentile for cadmium (55th percentile), zinc (40th percentile), or lead (50th percentile). However, the species mean chronic value for rainbow trout was in a high percentile for copper, lead, and zinc (∼68th–82nd percentile), but in a low percentile for cadmium (23rd percentile). The trout EC20s for each of the 4 metals and the sturgeon EC20s for cadmium or lead were above US Environmental Protection Agency chronic ambient water quality criteria (AWQC) or Washington State chronic water quality standards (WQS), whereas the sturgeon EC20s for copper or zinc were approximately equal to or below the chronic AWQC and WQS. In addition, acute 50% effect concentrations (EC50s) for copper obtained in the first 4 d of the chronic sturgeon test were below the final acute value used to derive acute AWQC and below acute WQS for copper.

  12. Synbiotic (Biomin imbo) alters gut bacterial microflora of Russian sturgeon, Acipenser guldenstadti (Brandt & Ratzeburg, 1833) in a time-dependent pattern.

    PubMed

    Vaezi, Mahdi; Khara, Hossein; Shenavar, Alireza

    2016-12-01

    We investigated the efficiency of Synbiotic (Biomin imbo) in alternation and stabilization of gut microflora of Russian sturgeon, Acipenser guldenstadti. For this purpose, five experimental treatments and one control group with three replicates were considered. In treatment groups, fish were fed with diet containing 1 (T1), 1.5 (T2), 2 (T3), 2.5 (T4) and 3 (T5) g Synbiotic/kg diet. In control group, fish were fed without supplement of Synbiotic. Sampling for bacterial studies was conducted at days 20, 40 and 60 after the beginning of the experiment. According to results, there were no significant differences in total bacterial count between Synbiotic treatments and also in comparison with control group 20 days after the beginning of the experiment (P > 0.05). At days 40 and 60 of experiment, the highest total bacterial counts were observed in control and T1 group respectively. At day 20, the lactic acid bacteria count was higher significantly in Synbiotic treatments compared to control group (P < 0.05). In all sampling times (i.e. days 20, 40 and 60), the highest lactic acid bacteria count was observed in fish fed with 3 g Synbiotic/kg diet i.e. treatment 5 (P < 0.05). In each experimental group, total bacteria and lactic acid bacteria counts increased significantly as the duration of experiment expanded. In this regard, these parameters were significantly higher at day 60 compared to day 40 and 20 (P < 0.05). In conclusion, our results showed that Synbiotic (Biomin imbo) alters and stabilizes efficiently the microflora of Russian sturgeon gut towards lactic acid bacteria in a time-dependent pattern.

  13. Effect of diet composition on growth performance, hepatic metabolism and antioxidant activities in Siberian sturgeon (Acipenser baerii, Brandt, 1869) submitted to starvation and refeeding.

    PubMed

    Babaei, Sedigheh; Abedian Kenari, Abdolmohammad; Hedayati, Mehdi; Yazdani Sadati, Mohammad Ali; Metón, Isidoro

    2016-12-01

    Many fish species undergo natural starvation periods. Adaptation to starvation is possible through the activation of behavioral, biochemical and physiological mechanisms. Knowledge of the effect of dietary nutrients on the intermediary metabolism during starvation and refeeding can be useful to improve fish health and optimize aquaculture production. To analyze the effect of dietary nutrients on liver metabolism of Siberian sturgeon (Acipenser baerii) submitted to starvation and refeeding, four isoenergetic diets differing in nutrient composition were designed: LP-St (38 % protein, 12 % lipid, 36 % carbohydrate), HP-St (44 % protein, 10 % lipid, 30 % carbohydrate), LP-L (38 % protein, 18 % lipid, 25 % carbohydrate) and HP-L (44 % protein, 16 % lipid, 22 % carbohydrate). Four groups of fish were fed 3 weeks to satiety with the corresponding diet, starved for 2 weeks and then refeed 5 weeks to satiety on the same diet. Starvation mobilized the hepatic lipid store to a greater extent than glycogen. Starvation increased superoxide dismutase activity irrespective of the diet, while low protein diets (LP-St and LP-L) increased catalase activity. The oxidative damage decreased after 5 weeks of refeeding. Refeeding the starved fish on the HP-St diet promoted the greatest growth performance. In addition to reporting for the first time the effect of diet composition on growth, liver composition and antioxidant activities in Siberian sturgeon submitted to starvation and refeeding, our findings suggest that refeeding on HP-St diet stimulated the use of dietary carbohydrates and allowed a protein sparing effect in Siberian sturgeon.

  14. Length-weight relationship and a relative condition factor equation for lake sturgeon (Acipenser fulvescens) from the St Clair River system (Michigan, USA)

    USGS Publications Warehouse

    Craig, J.M.; Thomas, M.V.; Nichols, S.J.

    2005-01-01

    Several USA state, federal, and Canadian agencies study lake sturgeon (Acipenser fulvescens) within the St Clair River and Lake St Clair, collectively referred to hereafter as the St Clair River (SCR) system. Previously, there has been no set standard for determining condition for SCR system lake sturgeon. Condition measures the variation from the expected weight for length as an indicator of fatness, general well-being, gonad development, etc. The aim of this project was to determine the length weight relationship of lake sturgeon caught from the SCR system, from which a relative condition factor (Kn) equation could be derived. Total length (TL, mm) and weight (W, kg) were measured for 1074 lake sturgeon (101 males and 16 females were identifiable) collected by setline and bottom trawl from the SCR system in May-September, 1997-2002. Analysis of covariance found no difference in the length-weight relationship between sampling gear or sex. Least-squares regression of log10W ?? log10TL produced the overall equation logW = 3.365logTL - 9.320. Using the exponential form of the slope and y-intercept, relative condition factor for lake sturgeon from the SCR system can be calculated as Kn - W/[(4.786 ?? 10-10)(TL3.365)]. Equations for males and females were also developed. Overall, body condition was significantly correlated with both age and girth; no significant difference in Kn by sex was found. In general, the SCR lake sturgeon population was near the upper ends of growth and condition ranges listed in the literature, comparable with those populations that are at similar latitudes. Although condition factors should be interpreted with caution, proper use of a standard equation provides a non-lethal measure of overall fish health that can be used by biologists and managers in ongoing efforts to restore lake sturgeon throughout the Great Lakes. ?? 2005 Blackwell Verlag, Berlin.

  15. Length-weight relationship and a relative condition factor equation for lake sturgeon (Acipenser fulvescens) from the St. Clair River system (Michigan, USA)

    USGS Publications Warehouse

    Craig, Jaquelyn M.; Thomas, Michael V.; Nichols, S. Jerrine

    2005-01-01

    Several USA state, federal, and Canadian agencies study lake sturgeon (Acipenser fulvescens) within the St Clair River and Lake St Clair, collectively referred to hereafter as the St Clair River (SCR) system. Previously, there has been no set standard for determining condition for SCR system lake sturgeon. Condition measures the variation from the expected weight for length as an indicator of fatness, general well-being, gonad development, etc. The aim of this project was to determine the length-weight relationship of lake sturgeon caught from the SCR system, from which a relative condition factor (Kn) equation could be derived. Total length (TL, mm) and weight (W, kg) were measured for 1074 lake sturgeon (101 males and 16 females were identifiable) collected by setline and bottom trawl from the SCR system in May-September, 1997-2002. Analysis of covariance found no difference in the length-weight relationship between sampling gear or sex. Least-squares regression of log10W x log10TL produced the overall equation logW = 3.365logTL - 9.320. Using the exponential form of the slope and y-intercept, relative condition factor for lake sturgeon from the SCR system can be calculated as Kn = W/ [(4.786 x 10-10)(TL3.365)]. Equations for males and females were also developed. Overall, body condition was significantly correlated with both age and girth; no significant difference in Kn by sex was found. In general, the SCR lake sturgeon population was near the upper ends of growth and condition ranges listed in the literature, comparable with those populations that are at similar latitudes. Although condition factors should be interpreted with caution, proper use of a standard equation provides a non-lethal measure of overall fish health that can be used by biologists and managers in ongoing efforts to restore lake sturgeon throughout the Great Lakes.

  16. Effects of pre-incubation of eggs in fresh water and varying sperm concentration on fertilization rate in sterlet sturgeon, Acipenser ruthenus.

    PubMed

    Siddique, Mohammad Abdul Momin; Butts, Ian Anthony Ernest; Psenicka, Martin; Linhart, Otomar

    2015-08-01

    Standardization of fertilization protocols for sterlet Acipenser ruthenus is crucial for improving reproductive techniques and for conservation purposes. Our objectives were to determine the number of sperm (tested 430,000:1, 43,000:1, 4300:1, 430:1 sperm to egg) required to fertilize eggs and explore how pre-incubation of eggs in freshwater for 0min, 0.5min, 1min, and 10min interacts with different sperm ratios. Fertilization success ranged from 29.7% at 430:1 to 84.2% at 430,000:1. Pre-incubation time had no effect on fertilization success at 430,000:1 and 43,000:1 sperm to egg ratios, while it was significant at the 4300:1 and 430:1 ratios. The use of adequate experimental suboptimal sperm to egg ratio revealed a positive effect of pre-incubation time, such that at the 430:1 ratio, 0.5min pre-incubation increased the fertilization rate than 10min. At 0min pre-incubation the proportion of fertilized eggs increased at the 430,000:1 ratio, while at 1min fertilization increased at the 4300:1 ratio. At the 10min pre-incubation time, fertilization increased at the 43,000:1 ratio. Moreover, at the 0.5min pre-incubation time, the 43,000:1 ratio increased the fertilization rate than the 430:1 ratio. Generally, for 430:1 ratio, the fertilization rate is lower than in control. Transmission electron microscopy showed that pre-incubation of eggs in water for <10min does not trigger a cortical reaction or the formation of a perivitelline space. Results suggest that with a low sperm to egg ratio 0.5 to 1min pre-incubation of eggs in freshwater prior to fertilization can enhance fertilization rate of sterlet.

  17. Developmental structure of the vertebral column, fins, scutes and scales in bester sturgeon, a hybrid of beluga Huso huso and sterlet Acipenser ruthenus.

    PubMed

    Zhang, X; Shimoda, K; Ura, K; Adachi, S; Takagi, Y

    2012-11-01

    In the larval bester, a hybrid sturgeon of beluga Huso huso and sterlet Acipenser ruthenus, development of cartilage around the notochord began 7 days post hatch (dph) (14.0 mm, total length, L(T)). The vertebral cartilage develops in the following sequence: basidorsals and basiventrals, neural canals, neural spines and ribs. The development of ribs remained incomplete in the largest specimen (181 dph, 179 mm L(T) ) that was examined. Endoskeletal development of the fins began 4 dph for the dorsal and anal fins, 6 dph for the pectoral fin and 10 dph for the caudal and pelvic fins. Complete elements of all fins were observed by 91 dph and complete ossification of fin rays was observed by 122 dph in the double-stained specimens. Observation of the histological sections, however, suggested that ossification occurred soon after the formation of the organic matrix in the fin rays. Dorsal scutes were first visible by 25 dph, followed by the lateral and ventral scutes, which were visible by 37 and 44 dph, respectively. The number of scutes was fixed at 44, 59 and 91 dph and ossification was complete by 59 (dorsal) and 91 dph (lateral and ventral scutes) in the double-stained specimens. Ossification occurred soon after the formation of the scute organic matrix in the histological sections. Four types of scales were observed in the H. huso×A. ruthenus hybrid. Median predorsal, preanal and small scales on the anterior section of the head were visible by 59 dph. Scales on the caudal fin were visible by 91 dph and a variable assemblage of scales anterior to the anal fin was visible by 122 dph. Both the scutes and scales developed in a process that is similar to that of intramembranous ossification.

  18. Effects of Replacement of Fish Meal by Soy Protein Isolate on the Growth, Digestive Enzyme Activity and Serum Biochemical Parameters for Juvenile Amur Sturgeon (Acipenser schrenckii).

    PubMed

    Xu, Q Y; Wang, C A; Zhao, Z G; Luo, L

    2012-11-01

    An 8-wk experiment was conducted to evaluate the effect of replacing fish meal (FM) with soy protein isolate (SPI) on the growth, digestive enzyme activity and serum biochemical parameters of juvenile Amur sturgeon (Acipenser schrenckii). SPI was used to replace 0, 25, 50, 62.5, 75, 87.5, 100% of dietary FM and 100% replacement supplemented crystalline amino acid. Healthy sturgeon with an average initial weight of 26.38±0.24 g were randomly assigned to 24 aquaria (8 treatments with triplicates each) at an initial stocking density of 11 fish per aquarium and cultured for 8 wks. The results showed that 75.00% or more substitution resulted in a poor weight gain rate, feed conversion ratio and survival rate compared to that of fish fed the control diet (p<0.05), whereas no significant differences were observed between diets of 25.00% to 62.50% substitution. Protease, lipase and amylase activity in foregut, mid-gut and hindgut were significantly (p<0.05) decreased by diets where SPI replacement levels were 62.50% or more. Levels of serum total protein (TP) and globulin decreased significantly from 21.03, 10.34 to 14.05, 5.63 g/L with the increasing dietary SPI (p<0.05), but alkaline phosphatase activity significantly increased (p<0.05). In addition, supplemental crystalline amino acid in the FM absence diet did not improve growth performance, intestine digestive enzyme activities and serum biochemical parameters. In conclusion, the results from this study showed adverse effects of inclusion of SPI in diets on growth performance, feed utilization and serum biochemical parameters in juvenile Amur sturgeon. Based on WGR and replacement ratio presented in this report, a 57.64% replacement level was recommended.

  19. Effects of replacing fish meal by soybean meal along with supplementing phosphorus and magnesium in diet on growth performance of Persian sturgeon, Acipenser persicus.

    PubMed

    Imanpoor, Mohamad Reza; Bagheri, Tahere

    2012-04-01

    Looking for replacing fish meal by cheaper and more sustainable protein sources is essential for reducing the cost of fish feeds. Soybean meal is a suitable alternative protein sources for carnivorous fish such as Persian sturgeon, Acipenser persicus. However, it contains antinutritional factors that may affect bioavailability of minerals and lead in reduced growth. Achieving a cost-effective diet that does not have negative effects on growth is the goal of aquaculture programs. A 10-week experiment was conducted with Persian sturgeon (352.07 ± 5.51 g) to determine the combined effects of phosphorous (SP), magnesium and phosphorous (SPMg), phytase (SF), phytase and magnesium (SFMg), phosphorous and phytase (SPF), phosphorous, magnesium and phytase (SPMgF) on weight gain, feed efficiency, specific growth rate, and condition factor. A control diet was prepared with fish meal as a control group. Inclusion of P, Mg, and phytase contents within soybean diets did not improve feed efficiency, and still, the control diet containing fish meal showed better weight gain and feed efficiency. Among soybean meal groups, feed efficiency and specific growth rate were significantly improved for fish fed the diet containing just phytase (SF) and both phytase and phosphorus (P ≤ 0.05). It was true for specific growth rate and condition factor. Phytase significantly enhanced growth whether included with or without phosphorous. This study showed that fish meal is more sufficient for Persian sturgeon, and soybean meal could be partly an alternative protein source if phosphorous supplied for fish by incorporation with microbial phytase or phosphorous.

  20. Complete intracellular pH protection during extracellular pH depression is associated with hypercarbia tolerance in white sturgeon, Acipenser transmontanus.

    PubMed

    Baker, D W; Matey, V; Huynh, K T; Wilson, J M; Morgan, J D; Brauner, C J

    2009-06-01

    Sturgeons are among the most CO2 tolerant of fishes investigated to date. However, the basis of this exceptional CO2 tolerance is unknown. Here, white sturgeon, Acipenser transmontanus, were exposed to elevated CO2 to investigate the mechanisms associated with short-term hypercarbia tolerance. During exposure to 1.5 kPa Pco2, transient blood pH [extracellular pH (pHe)] depression was compensated within 24 h and associated with net plasma HCO3- accumulation and equimolar Cl- loss, and changes in gill morphology, such as a decrease in apical surface area of mitochondrial-rich cells. These findings indicate that pHe recovery at this level of hypercarbia is accomplished in a manner similar to most freshwater teleost species studied to date, although branchial mechanisms involved may differ. White sturgeon exposed to more severe hypercarbia (3 and 6 kPa Pco2) for 48 h exhibited incomplete pH compensation in blood and red blood cells. Despite pHe depression, intracellular pH (pHi) of white muscle, heart, brain, and liver did not decrease during a transient (6 h of 1.5 kPa Pco2) or prolonged (48 h at 3 and 6 kPa Pco2 blood acidosis. This pHi protection was not due to high intrinsic buffering in tissues. Such tight active cellular regulation of pHi in the absence of pHe compensation represents a unique pattern for non-air-breathing fishes, and we hypothesize that it is the basis for the exceptional CO2 tolerance of white sturgeon and, likely, other CO2 tolerant fishes. Further research to elucidate the specific mechanisms responsible for this tremendous pH regulatory capacity in tissues of white sturgeon is warranted.

  1. Interaction of osmoregulatory and acid-base compensation in white sturgeon (Acipenser transmontanus) during exposure to aquatic hypercarbia and elevated salinity.

    PubMed

    Shaughnessy, Ciaran A; Baker, Dan W; Brauner, Colin J; Morgan, John D; Bystriansky, Jason S

    2015-07-10

    Migratory fishes encounter a variety of environmental conditions, including changes in salinity, temperature, and dissolved gases, and it is important to understand how these fishes are able to acclimate to multiple environmental stressors. The gill is the primary site of both acid-base balance and ion regulation in fishes. Many ion transport mechanisms involved with acid-base compensation are also required for the regulation of plasma Na(+) and Cl(+), the predominant extracellular ions, potentially resulting in a strong interaction between iono- and acid-base regulation. The present study examined the physiological interaction of elevated dissolved CO2 (an acid-base disturbance) on osmoregulation during seawater acclimation (an ionoregulatory disturbance) in juvenile white sturgeon (Acipenser transmontanus). Blood pH (pHe), plasma [HCO3(-)], [Na(+)], [Cl(-)], and osmolality, white muscle water content, and gill Na(+)/K(+)-ATPase (NKA) and Na(+)/K(+)/2Cl(-) cotransporter (NKCC) abundance were examined over a 10-day seawater (SW) acclimation period under normocarbia (NCSW) or during prior and continued exposure to hypercarbia (HCSW), and compared to a normocarbic freshwater (NCFW) control. Hypercarbia induced a severe extracellular acidosis (from pH 7.65 to pH 7.2) in HCSW sturgeon, and these fish had a 2-fold greater rise in plasma osmolarity over NCSW by day 2 of SW exposure. Interestingly, pHe recovery in HCSW was associated more prominently with an elevation in plasma Na(+) prior to osmotic recovery and more prominently with a reduction in plasma Cl(-) following osmotic recovery, indicating a biphasic response as the requirements of osmoregulation transitioned from ion-uptake to ion-excretion throughout SW acclimation. These results imply a prioritization of osmoregulatory recovery over acid-base recovery in this period of combined exposure to acid-base and ionoregulatory disturbances.

  2. Chronic sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to cadmium, copper, lead, or zinc in laboratory water-only exposures.

    PubMed

    Wang, Ning; Ingersoll, Christopher G; Dorman, Rebecca A; Brumbaugh, William G; Mebane, Christopher A; Kunz, James L; Hardesty, Doug K

    2014-10-01

    Chronic toxicity of cadmium, copper, lead, or zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) was evaluated in water-only exposures started with newly hatched larvae or approximately 1-mo-old juveniles. The 20% effect concentration (EC20) for cadmium from the sturgeon tests was higher than the EC20 from the trout tests, whereas the EC20 for copper, lead, or zinc for the sturgeon were lower than those EC20s for the trout. When the EC20s from the present study were included in compiled toxicity databases for all freshwater species, species mean chronic value for white sturgeon was in a relatively low percentile of the species sensitivity distribution for copper (9th percentile) and in the middle percentile for cadmium (55th percentile), zinc (40th percentile), or lead (50th percentile). However, the species mean chronic value for rainbow trout was in a high percentile for copper, lead, and zinc (∼68th-82nd percentile), but in a low percentile for cadmium (23rd percentile). The trout EC20s for each of the 4 metals and the sturgeon EC20s for cadmium or lead were above US Environmental Protection Agency chronic ambient water quality criteria (AWQC) or Washington State chronic water quality standards (WQS), whereas the sturgeon EC20s for copper or zinc were approximately equal to or below the chronic AWQC and WQS. In addition, acute 50% effect concentrations (EC50s) for copper obtained in the first 4 d of the chronic sturgeon test were below the final acute value used to derive acute AWQC and below acute WQS for copper.

  3. Interaction of osmoregulatory and acid-base compensation in white sturgeon (Acipenser transmontanus) during exposure to aquatic hypercarbia and elevated salinity.

    PubMed

    Shaughnessy, Ciaran A; Baker, Dan W; Brauner, Colin J; Morgan, John D; Bystriansky, Jason S

    2015-09-01

    Migratory fishes encounter a variety of environmental conditions, including changes in salinity, temperature and dissolved gases, and it is important to understand how these fishes are able to acclimate to multiple environmental stressors. The gill is the primary site of both acid-base balance and ion regulation in fishes. Many ion transport mechanisms involved with acid-base compensation are also required for the regulation of plasma Na(+) and Cl(+), the predominant extracellular ions, potentially resulting in a strong interaction between ionoregulation and acid-base regulation. The present study examined the physiological interaction of elevated dissolved CO2 (an acid-base disturbance) on osmoregulation during seawater acclimation (an ionoregulatory disturbance) in juvenile white sturgeon (Acipenser transmontanus). Blood pH (pHe), plasma [HCO3 (-)], [Na(+)], [Cl(-)] and osmolality, white muscle water content, and gill Na(+)/K(+)-ATPase (NKA) and Na(+)/K(+)/2Cl(-) co-transporter (NKCC) abundance were examined over a 10 day seawater (SW) acclimation period under normocarbia (NCSW) or during prior and continued exposure to hypercarbia (HCSW), and compared with a normocarbic freshwater (NCFW) control. Hypercarbia induced a severe extracellular acidosis (from pH 7.65 to pH 7.2) in HCSW sturgeon, and these fish had a 2-fold greater rise in plasma osmolarity over NCSW by day 2 of SW exposure. Interestingly, pHe recovery in HCSW was associated more prominently with an elevation in plasma Na(+) prior to osmotic recovery and more prominently with a reduction in plasma Cl(-) following osmotic recovery, indicating a biphasic response as the requirements of osmoregulation transitioned from ion-uptake to ion-excretion throughout SW acclimation. These results imply a prioritization of osmoregulatory recovery over acid-base recovery in this period of combined exposure to acid-base and ionoregulatory disturbances.

  4. Effects of the supplementation of vitamin D3 on the growth and vitamin D metabolites in juvenile Siberian sturgeon (Acipenser baerii).

    PubMed

    Wang, Liansheng; Xu, Hong; Wang, Yang; Wang, Chang'an; Li, Jinnan; Zhao, Zhigang; Luo, Liang; Du, Xue; Xu, Qiyou

    2017-01-23

    The objective of this study was to evaluate the effects of the supplementation of vitamin D3 on the growth, vitamin D metabolites, and osteocalcin secretion in juvenile Siberian sturgeon (Acipenser baerii). A 90-day growth trial was conducted with juvenile Siberian sturgeon (initial body weight 3.47 ± 0.14 g) fed seven isonitrogenous and isoenergetic practical diets (45% CP and 13% lipid) containing 60 (basal diet), 240, 450, 880, 1670, 3300, or 1.0 × 10(5) IU/kg feed (D60~D 1.0 × 10(5)) vitamin D3. The results showed that weight gain and specific growth rate increased as the dietary vitamin D3 levels increased from 450 to 3300 IU/kg (P < 0.05). The fish fed with D1670 and D3300 diets had higher crude lipid and ash levels than the fish fed the D60 diet (P < 0.05). The fish fed D880, D1670, or D3300 diets had higher 25-OH-D3 and 1,25-(OH)2-D3 levels than the fish fed the D60 diet (P < 0.05). The fish fed D880, D1670, D3300, or D1.0 × 10(5) diets had higher osteocalcin levels than the fish fed the D60 diet (P < 0.05). Based on the broken line method analysis of weight gain and osteocalcin, the dietary vitamin D3 requirement of juvenile Siberian sturgeon was estimated to be 1683.30 and 1403.27 IU/kg per diet, respectively.

  5. Neomycin damage and regeneration of hair cells in both mechanoreceptor and electroreceptor lateral line organs of the larval Siberian sturgeon (Acipenser baerii).

    PubMed

    Fan, Chunxin; Zou, Sha; Wang, Jian; Zhang, Bo; Song, Jiakun

    2016-05-01

    The lateral line found in some amphibians and fishes has two distinctive classes of sensory organs: mechanoreceptors (neuromasts) and electroreceptors (ampullary organs). Hair cells in neuromasts can be damaged by aminoglycoside antibiotics and they will regenerate rapidly afterward. Aminoglycoside sensitivity and the capacity for regeneration have not been investigated in ampullary organs. We treated Siberian sturgeon (Acipenser baerii) larvae with neomycin and observed loss and regeneration of sensory hair cells in both organs by labeling with DASPEI and scanning electron microscopy (SEM). The numbers of sensory hair cells in both organs were reduced to the lowest levels at 6 hours posttreatment (hpt). New sensory hair cells began to appear at 12 hpt and were regenerated completely in 7 days. To reveal the possible mechanism for ampullary hair cell regeneration, we analyzed cell proliferation and the expression of neural placodal gene eya1 during regeneration. Both cell proliferation and eya1 expression were concentrated in peripheral mantle cells and both increased to the highest level at 12 hpt, which is consistent with the time course for regeneration of the ampullary hair cells. Furthermore, we used Texas Red-conjugated gentamicin in an uptake assay following pretreatment with a cation channel blocker (amiloride) and found that entry of the antibiotic was suppressed in both organs. Together, our results indicate that ampullary hair cells in Siberian sturgeon larvae can be damaged by neomycin exposure and they can regenerate rapidly. We suggest that the mechanisms for aminoglycoside uptake and hair cell regeneration are conserved for mechanoreceptors and electroreceptors. J. Comp. Neurol. 524:1443-1456, 2016. © 2015 Wiley Periodicals, Inc.

  6. Predicted effects of future climate warming on thermal habitat suitability for Lake Sturgeon (Acipenser fulvescens, Rafinesque, 1817) in rivers in Wisconsin, USA

    USGS Publications Warehouse

    Lyons, John D.; Stewart, Jana S.

    2015-01-01

    The Lake Sturgeon (Acipenser fulvescens, Rafinesque, 1817) may be threatened by future climate warming. The purpose of this study was to identify river reaches in Wisconsin, USA, where they might be vulnerable to warming water temperatures. In Wisconsin, A. fulvescens is known from 2291 km of large-river habitat that has been fragmented into 48 discrete river-lake networks isolated by impassable dams. Although the exact temperature tolerances are uncertain, water temperatures above 28–30°C are potentially less suitable for this coolwater species. Predictions from 13 downscaled global climate models were input to a lotic water temperature model to estimate amounts of potential thermally less-suitable habitat at present and for 2046–2065. Currently, 341 km (14.9%) of the known habitat are estimated to regularly exceed 28°C for an entire day, but only 6 km (0.3%) to exceed 30°C. In 2046–2065, 685–2164 km (29.9–94.5%) are projected to exceed 28°C and 33–1056 km (1.4–46.1%) to exceed 30°C. Most river-lake networks have cooler segments, large tributaries, or lakes that might provide temporary escape from potentially less suitable temperatures, but 12 short networks in the Lower Fox and Middle Wisconsin rivers totaling 93.6 km are projected to have no potential thermal refugia. One possible adaptation to climate change could be to provide fish passage or translocation so that riverine Lake Sturgeon might have access to more thermally suitable habitats.

  7. Toxicity of smelter slag-contaminated sediments from Upper Lake Roosevelt and associated metals to early life stage White Sturgeon (Acipenser transmontanus Richardson, 1836)

    USGS Publications Warehouse

    Little, E.E.; Calfee, R.D.; Linder, G.

    2014-01-01

    The toxicity of five smelter slag-contaminated sediments from the upper Columbia River and metals associated with those slags (cadmium, copper, zinc) was evaluated in 96-h exposures of White Sturgeon (Acipenser transmontanus Richardson, 1836) at 8 and 30 days post-hatch. Leachates prepared from slag-contaminated sediments were evaluated for toxicity. Leachates yielded a maximum aqueous copper concentration of 11.8 μg L−1 observed in sediment collected at Dead Man's Eddy (DME), the sampling site nearest the smelter. All leachates were nonlethal to sturgeon that were 8 day post-hatch (dph), but leachates from three of the five sediments were toxic to fish that were 30 dph, suggesting that the latter life stage is highly vulnerable to metals exposure. Fish maintained consistent and prolonged contact with sediments and did not avoid contaminated sediments when provided a choice between contaminated and uncontaminated sediments. White Sturgeon also failed to avoid aqueous copper (1.5–20 μg L−1). In water-only 96-h exposures of 35 dph sturgeon with the three metals, similar toxicity was observed during exposure to water spiked with copper alone and in combination with cadmium and zinc. Cadmium ranging from 3.2 to 41 μg L−1 or zinc ranging from 21 to 275 μg L−1 was not lethal, but induced adverse behavioral changes including a loss of equilibrium. These results suggest that metals associated with smelter slags may pose an increased exposure risk to early life stage sturgeon if fish occupy areas contaminated by slags.

  8. Acute sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to copper, cadmium, or zinc in water-only laboratory exposures.

    PubMed

    Calfee, Robin D; Little, Edward E; Puglis, Holly J; Scott, Erinn; Brumbaugh, William G; Mebane, Christopher A

    2014-10-01

    The acute toxicity of cadmium, copper, and zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) were determined for 7 developmental life stages in flow-through water-only exposures. Metal toxicity varied by species and by life stage. Rainbow trout were more sensitive to cadmium than white sturgeon across all life stages, with median effect concentrations (hardness-normalized EC50s) ranging from 1.47 µg Cd/L to 2.62 µg Cd/L with sensitivity remaining consistent during later stages of development. Rainbow trout at 46 d posthatch (dph) ranked at the 2nd percentile of a compiled database for Cd species sensitivity distribution with an EC50 of 1.46 µg Cd/L and 72 dph sturgeon ranked at the 19th percentile (EC50 of 3.02 µg Cd/L). White sturgeon were more sensitive to copper than rainbow trout in 5 of the 7 life stages tested with biotic ligand model (BLM)-normalized EC50s ranging from 1.51 µg Cu/L to 21.9 µg Cu/L. In turn, rainbow trout at 74 dph and 95 dph were more sensitive to copper than white sturgeon at 72 dph and 89 dph, indicating sturgeon become more tolerant in older life stages, whereas older trout become more sensitive to copper exposure. White sturgeon at 2 dph, 16 dph, and 30 dph ranked in the lower percentiles of a compiled database for copper species sensitivity distribution, ranking at the 3rd (2 dph), 5th (16 dph), and 10th (30 dph) percentiles. White sturgeon were more sensitive to zinc than rainbow trout for 1 out of 7 life stages tested (2 dph with an biotic ligand model-normalized EC50 of 209 µg Zn/L) and ranked in the 1st percentile of a compiled database for zinc species sensitivity distribution.

  9. Efficacy of a sensory deterrent and pipe modifications in decreasing entrainment of juvenile green sturgeon (Acipenser medirostris) at unscreened water diversions.

    PubMed

    Poletto, Jamilynn B; Cocherell, Dennis E; Mussen, Timothy D; Ercan, Ali; Bandeh, Hossein; Levent Kavvas, M; Cech, Joseph J; Fangue, Nann A

    2014-01-01

    Water projects designed to extract fresh water for local urban, industrial and agricultural use throughout rivers and estuaries worldwide have contributed to the fragmentation and degradation of suitable habitat for native fishes. The number of water diversions located throughout the Sacramento-San Joaquin watershed in California's Central Valley exceeds 3300, and the majority of these are unscreened. Many anadromous fish species are susceptible to entrainment into these diversions, potentially impacting population numbers. In the laboratory, juvenile green sturgeon (Acipenser medirostris) have been shown to have high entrainment rates into unscreened diversions compared with those of other native California fish species, which may act as a significant source of mortality for this already-threatened species. Therefore, we tested the efficacy of a sensory deterrent (strobe light) and two structural pipe modifications (terminal pipe plate and upturned pipe configuration) in decreasing the entrainment of juvenile green sturgeon (mean mass ± SEM = 162.9 ± 4.0 g; mean fork length = 39.4 ± 0.3 cm) in a large (>500 kl) outdoor flume fitted with a water-diversion pipe 0.46 m in diameter. While the presence of the strobe light did not affect fish entrainment rates, the terminal pipe plate and upturned pipe modifications significantly decreased the proportion of fish entrained out of the total number tested relative to control conditions (0.13 ± 0.02 and 0.03 ± 0.02 vs. 0.44 ± 0.04, respectively). These data suggest that sensory deterrents using visual stimuli are not an effective means to reduce diversion pipe interactions for green sturgeon, but that structural alterations to diversions can successfully reduce entrainment for this species. Our results are informative for the development of effective management strategies to mitigate the impacts of water diversions on sturgeon populations and suggest that effective restoration

  10. Acute sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to copper, cadmium, or zinc in water-only laboratory exposures

    USGS Publications Warehouse

    Calfee, Robin D.; Little, Edward E.; Puglis, Holly J.; Scott, Erinn L.; Brumbaugh, William G.; Mebane, Christopher A.

    2014-01-01

    The acute toxicity of cadmium, copper, and zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) were determined for 7 developmental life stages in flow-through water-only exposures. Metal toxicity varied by species and by life stage. Rainbow trout were more sensitive to cadmium than white sturgeon across all life stages, with median effect concentrations (hardness-normalized EC50s) ranging from 1.47 µg Cd/L to 2.62 µg Cd/L with sensitivity remaining consistent during later stages of development. Rainbow trout at 46 d posthatch (dph) ranked at the 2nd percentile of a compiled database for Cd species sensitivity distribution with an EC50 of 1.46 µg Cd/L and 72 dph sturgeon ranked at the 19th percentile (EC50 of 3.02 µg Cd/L). White sturgeon were more sensitive to copper than rainbow trout in 5 of the 7 life stages tested with biotic ligand model (BLM)-normalized EC50s ranging from 1.51 µg Cu/L to 21.9 µg Cu/L. In turn, rainbow trout at 74 dph and 95 dph were more sensitive to copper than white sturgeon at 72 dph and 89 dph, indicating sturgeon become more tolerant in older life stages, whereas older trout become more sensitive to copper exposure. White sturgeon at 2 dph, 16 dph, and 30 dph ranked in the lower percentiles of a compiled database for copper species sensitivity distribution, ranking at the 3rd (2 dph), 5th (16 dph), and 10th (30 dph) percentiles. White sturgeon were more sensitive to zinc than rainbow trout for 1 out of 7 life stages tested (2 dph with an biotic ligand model–normalized EC50 of 209 µg Zn/L) and ranked in the 1st percentile of a compiled database for zinc species sensitivity distribution.

  11. Length-weight relationship and a relative condition factor equation for lake sturgeon (Acipenser fulvescens) from the St. Clair River system (Michigan, USA)

    USGS Publications Warehouse

    Craig, Jaquelyn M.; Thomas, Michael V.; Nichols, Susan Jerrine

    2005-01-01

    Several USA state, federal, and Canadian agencies study lake sturgeon (Acipenser fulvescens) within the St Clair River and Lake St Clair, collectively referred to hereafter as the St Clair River (SCR) system. Previously, there has been no set standard for determining condition for SCR system lake sturgeon. Condition measures the variation from the expected weight for length as an indicator of fatness, general well-being, gonad development, etc. The aim of this project was to determine the length–weight relationship of lake sturgeon caught from the SCR system, from which a relative condition factor (Kn) equation could be derived. Total length (TL, mm) and weight (W, kg) were measured for 1074 lake sturgeon (101 males and 16 females were identifiable) collected by setline and bottom trawl from the SCR system in May–September, 1997–2002. Analysis of covariance found no difference in the length–weight relationship between sampling gear or sex. Least-squares regression of log10W × log10TL produced the overall equation logW = 3.365logTL − 9.320. Using the exponential form of the slope and y-intercept, relative condition factor for lake sturgeon from the SCR system can be calculated as Kn = W/[(4.786 × 10−10)(TL3.365)]. Equations for males and females were also developed. Overall, body condition was significantly correlated with both age and girth; no significant difference in Kn by sex was found. In general, the SCR lake sturgeon population was near the upper ends of growth and condition ranges listed in the literature, comparable with those populations that are at similar latitudes. Although condition factors should be interpreted with caution, proper use of a standard equation provides a non-lethal measure of overall fish health that can be used by biologists and managers in ongoing efforts to restore lake sturgeon throughout the Great Lakes.

  12. Efficacy of a sensory deterrent and pipe modifications in decreasing entrainment of juvenile green sturgeon (Acipenser medirostris) at unscreened water diversions

    PubMed Central

    Poletto, Jamilynn B.; Cocherell, Dennis E.; Mussen, Timothy D.; Ercan, Ali; Bandeh, Hossein; Levent Kavvas, M.; Cech, Joseph J.; Fangue, Nann A.

    2014-01-01

    Water projects designed to extract fresh water for local urban, industrial and agricultural use throughout rivers and estuaries worldwide have contributed to the fragmentation and degradation of suitable habitat for native fishes. The number of water diversions located throughout the Sacramento–San Joaquin watershed in California's Central Valley exceeds 3300, and the majority of these are unscreened. Many anadromous fish species are susceptible to entrainment into these diversions, potentially impacting population numbers. In the laboratory, juvenile green sturgeon (Acipenser medirostris) have been shown to have high entrainment rates into unscreened diversions compared with those of other native California fish species, which may act as a significant source of mortality for this already-threatened species. Therefore, we tested the efficacy of a sensory deterrent (strobe light) and two structural pipe modifications (terminal pipe plate and upturned pipe configuration) in decreasing the entrainment of juvenile green sturgeon (mean mass ± SEM = 162.9 ± 4.0 g; mean fork length = 39.4 ± 0.3 cm) in a large (>500 kl) outdoor flume fitted with a water-diversion pipe 0.46 m in diameter. While the presence of the strobe light did not affect fish entrainment rates, the terminal pipe plate and upturned pipe modifications significantly decreased the proportion of fish entrained out of the total number tested relative to control conditions (0.13 ± 0.02 and 0.03 ± 0.02 vs. 0.44 ± 0.04, respectively). These data suggest that sensory deterrents using visual stimuli are not an effective means to reduce diversion pipe interactions for green sturgeon, but that structural alterations to diversions can successfully reduce entrainment for this species. Our results are informative for the development of effective management strategies to mitigate the impacts of water diversions on sturgeon populations and suggest that effective restoration

  13. Tissue specificity of aryl hydrocarbon receptor (AhR) mediated responses and relative sensitivity of white sturgeon (Acipenser transmontanus) to an AhR agonist.

    PubMed

    Doering, Jon A; Wiseman, Steve; Beitel, Shawn C; Tendler, Brett J; Giesy, John P; Hecker, Markus

    2012-06-15

    Sturgeons are endangered in some parts of the world. Due to their benthic nature and longevity sturgeon are at greater risk of exposure to bioaccumulative contaminants such as dioxin-like compounds that are associated with sediments. Despite their endangered status, little research has been conducted to characterize the relative responsiveness of sturgeon to dioxin-like compounds. In an attempt to study the biological effects and possible associated risks of exposure to dioxin-like compounds in sturgeon, the molecular and biochemical responses of white sturgeon (Acipenser transmontanus) to a model aryl hydrocarbon receptor (AhR) agonist, β-naphthoflavone (βNF) were investigated. White sturgeon were injected intraperitoneally with one of three doses of βNF (0, 50, or 500mg/kg, bw). Rainbow trout (Oncorhynchus mykiss) were used as a reference species since their responses have been well characterized in the past. Three days following injection with βNF, fish were euthanized and livers, gills, and intestines collected for biochemical and molecular analyses. White sturgeon exposed to βNF had significantly greater ethoxyresorufin O-deethylase (EROD) activity in liver (up to 37-fold), gill (up to 41-fold), and intestine (up to 36-fold) than did unexposed controls. Rainbow trout injected with βNF exhibited EROD activity that was significantly greater in liver (88-fold), than that of controls, but was undetectable in gills or intestine. Abundance of CYP1A transcript displayed a comparable pattern of tissue-specific induction with intestine (up to 189-fold), gills (up to 53-fold), and liver (up to 21-fold). Methoxyresorufin O-deethylase (MROD) and pentoxyresorufin O-deethylase (PROD) activities were undetectable in unexposed white sturgeon tissues while exposed tissues displayed MROD activity that was only moderately greater than the activity that could be detected. Differential inducibility among liver, gill, and intestine following exposure to an AhR agonist is

  14. Acute sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to copper, cadmium, or zinc in water-only laboratory exposures

    PubMed Central

    Calfee, Robin D; Little, Edward E; Puglis, Holly J; Scott, Erinn; Brumbaugh, William G; Mebane, Christopher A

    2014-01-01

    The acute toxicity of cadmium, copper, and zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) were determined for 7 developmental life stages in flow-through water-only exposures. Metal toxicity varied by species and by life stage. Rainbow trout were more sensitive to cadmium than white sturgeon across all life stages, with median effect concentrations (hardness-normalized EC50s) ranging from 1.47 µg Cd/L to 2.62 µg Cd/L with sensitivity remaining consistent during later stages of development. Rainbow trout at 46 d posthatch (dph) ranked at the 2nd percentile of a compiled database for Cd species sensitivity distribution with an EC50 of 1.46 µg Cd/L and 72 dph sturgeon ranked at the 19th percentile (EC50 of 3.02 µg Cd/L). White sturgeon were more sensitive to copper than rainbow trout in 5 of the 7 life stages tested with biotic ligand model (BLM)-normalized EC50s ranging from 1.51 µg Cu/L to 21.9 µg Cu/L. In turn, rainbow trout at 74 dph and 95 dph were more sensitive to copper than white sturgeon at 72 dph and 89 dph, indicating sturgeon become more tolerant in older life stages, whereas older trout become more sensitive to copper exposure. White sturgeon at 2 dph, 16 dph, and 30 dph ranked in the lower percentiles of a compiled database for copper species sensitivity distribution, ranking at the 3rd (2 dph), 5th (16 dph), and 10th (30 dph) percentiles. White sturgeon were more sensitive to zinc than rainbow trout for 1 out of 7 life stages tested (2 dph with an biotic ligand model–normalized EC50 of 209 µg Zn/L) and ranked in the 1st percentile of a compiled database for zinc species sensitivity distribution. Environ Toxicol Chem 2014;33:2259–2272. © 2014. The Authors. This article is a US government work and, as such, is in the public domain in the United States of America. Environmental Toxicology and Chemistry published byWiley Periodicals, Inc. on behalf of SETAC. This is an open access article

  15. Acute toxicity of copper, lead, cadmium, and zinc to early life stages of white sturgeon (Acipenser transmontanus) in laboratory and Columbia River water.

    PubMed

    Vardy, David W; Santore, Robert; Ryan, Adam; Giesy, John P; Hecker, Markus

    2014-01-01

    Populations of white sturgeon (Acipenser transmontanus) are in decline in North America. This is attributed, primarily, to poor recruitment, and white sturgeon are listed as threatened or endangered in several parts of British Columbia, Canada, and the United States. In the Columbia River, effects of metals have been hypothesized as possible contributing factors. Previous work has demonstrated that early life stage white sturgeon are particularly sensitive to certain metals, and concerns over the level of protectiveness of water quality standards are justified. Here we report results from acute (96-h) toxicity tests for copper (Cu), cadmium (Cd), zinc (Zn), and lead (Pb) from parallel studies that were conducted in laboratory water and in the field with Columbia River water. Water effect ratios (WERs) and sensitivity parameters (i.e., median lethal accumulations, or LA50s) were calculated to assess relative bioavailability of these metals in Columbia River water compared to laboratory water, and to elucidate possible differences in sensitivity of early life stage white sturgeon to the same concentrations of metals when tested in the different water sources. For Cu and Pb, white sturgeon toxicity tests were initiated at two life stages, 8 and 40 days post-hatch (dph), and median lethal concentrations (LC50s) ranged between 9-25 μg Cu/L and 177-1,556 μg Pb/L. LC50s for 8 dph white sturgeon exposed to Cd in laboratory water and river water were 14.5 and 72 μg/L, respectively. Exposure of 8 dph white sturgeon to Zn in laboratory and river water resulted in LC50s of 150 and 625 μg/L, respectively. Threshold concentrations were consistently less in laboratory water compared with river water, and as a result, WERs were greater than 1 in all cases. In addition, LA50s were consistently greater in river water exposures compared with laboratory exposures in all paired tests. These results, in combination with results from the biotic ligand model, suggest that the observed

  16. Acute and chronic sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to cadmium, copper, lead, or zinc in laboratory water-only exposures

    USGS Publications Warehouse

    Ingersoll, Christopher G.; Contributions by Wang, Ning; Calfee, Robin D.; Beahan, Erinn; Brumbaugh, William G.; Dorman, Rebecca A.; Hardesty, Doug K.; Kunz, James L.; Little, Edward E.; Mebane, Christopher A.; Puglis, Holly J.

    2014-01-01

    White sturgeon (Acipenser transmontanus) are experiencing poor recruitment in the trans boundary reach of the upper Columbia River in eastern Washington State. Limited toxicity data indicated that early life stages of white sturgeon are sensitive to metals. In acute 4-day (d) exposures with larval white sturgeon, previous studies have reported that the 4-day median lethal concentrations (LC50) based on biotic ligand model (BLM) normalization for copper were below the U.S. Environmental Protection Agency national recommended acute water-quality criterion. In previously published chronic 66-d exposures starting with newly fertilized eggs of white sturgeon, 20-percent lethal effect concentrations (LC20s) for copper, cadmium, or zinc generally were within a factor of two of the chronic values of the most sensitive fish species in the databases of the U.S. Environmental Protection Agency water-quality criteria (WQC) for the three metals. However, there were some uncertainties in the chronic exposures previously performed with white sturgeon, including (1) low control survival (37 percent), (2) more control fish tested in each replicate compared to other treatments, (3) limited replication of treatments (n=2), (4) lack of reported growth data (such as dry weight), and (5) wide dilution factors for exposure concentrations (6- to 8-fold dilutions). The U.S. Environmental Protection Agency concluded that additional studies are needed to generate more toxicity data to better define lethal and sublethal toxicity thresholds for metals for white sturgeon. The objective of the study was to further evaluate the acute and chronic toxicity of cadmium, copper, lead, or zinc to early life stages of white sturgeon in water-only exposures. Toxicity tests also were performed with commonly tested rainbow trout (Oncorhynchus mykiss) under similar test conditions to determine the relative sensitivity between white sturgeon and rainbow trout to these metals. Toxicity data generated from

  17. Application of Bomb Radiocarbon Chronologies to Shortfin Mako (Isurus oxyrinchus)

    SciTech Connect

    Ardizzone, D; Cailliet, G M; Natanson, L J; Andrews, A H; Kerr, L A; Brown, T A

    2007-07-16

    There is an ongoing disagreement regarding the aging of the shortfin mako due to a difference of interpretation in the periodic deposition of vertebral growth band pairs, especially for the larger size classes. Using analysis of length-month information, tagging data, and length-frequency analysis, concluded that two band pairs were formed in the vertebral centrum every year (biannual band-pair interpretation). Cailliet et al. (1983), however, presented growth parameters based on the common assumption that one band pair forms annually (annual band-pair interpretation). Therefore, growth rates obtained by Pratt & Casey (1983) were twice that of Cailliet et al. (1983) and could lead to age discrepancies of about 15 years for maximum estimated ages on the order of 30 from the annual band-pair interpretation. Serious consequences in the population dynamics could occur for this species if inputs are based on an invalid age interpretation. The latest Fishery Management Plan (FMP) for Highly Migratory Species (HMS), for example, adopted the biannual band pair deposition hypothesis because it apparently fit the observed growth patterns best (Pacific Fishery Management Council 2003). However, the ongoing uncertainty about the aging of the shortfin mako was acknowledged and it was recommended that an endeavor to resolve this issue be made. Since 1983, five additional studies on the age and growth of the shortfin mako have been conducted (Chan 2001, Campana et al. 2002, Hsu 2003, Ribot-Carballal et al. 2005, Bishop et al. 2006). Using Marginal Increment Ratio (MIR), Hsu (2003) indicated the formation of annual translucent bands from July to September in western North Pacific Ocean shortfin makos. Using Marginal Increment Analysis (MIA) Ribot-Carballal et al. (2005) supported the annual band-pair interpretation for 109 shortfin makos collected in the eastern Pacific Ocean. Although the study provided support for annual band-pair deposition, no statistical test was performed and the number of samples for MIA analysis was insufficient for some months. Hence, unequivocal validation of shortfin mako age estimates has yet to be accomplished. Atmospheric testing of thermonuclear devices in the 1950s and 1960s effectively doubled the natural atmospheric radiocarbon ({sup 14}C). The elevated {sup 14}C levels were first recorded in 1957-58, with a peak around 1963. As a consequence, {sup 14}C entered the ocean through gas exchange with the atmosphere at the ocean surface and in terrestrial runoff. Despite variable oceanographic conditions, a worldwide rise of the bomb {sup 14}C signal entered the ocean mixed layer as dissolved inorganic carbon (DIC) in 1957-58. The large amounts of {sup 14}C released from the bomb tests produced a signature that can be followed through time, throughout the marine food web, and into deeper waters. The marked increase of radiocarbon levels was first measured in the DIC of seawater and in biogenic marine carbonates of hermatypic corals in Florida. Subsequently, this record was documented in corals from other regions and in the thallus of rhodoliths. The accumulation of radiocarbon in the hard parts of most marine organisms in the mixed layer (such as fish otoliths and bivalves) was synchronous with the coral time-series. This technique has been used to validate age estimates and longevity of numerous bony fishes to date, as well as to establish bomb radiocarbon chronologies from different oceans. In the first application of this technique to lamnoid sharks, validated annual band-pair deposition in vertebral growth bands for the porbeagle (Lamna nasus) aged up to 26 years. Radiocarbon values from samples obtained from 15 porbeagle caught in the western North Atlantic Ocean (some of which were known-age) produced a chronology similar in magnitude to the reference carbonate chronology for that region. The observed phase shift of about 3 years was attributed to different sources of carbon between vertebrae and those for otoliths, bivalves and corals. In the same study by Campana et al. (2002), a single vertebra from a shortfin mako caught in 1977 was aged at 21 and 10 years, using the annual versus the biannual deposition hypotheses, respectively. Vertebral samples were extracted from the first, last, and two intermediate bands and were assayed for radiocarbon. The results indicated the aging interpretation for the vertebra from this fish best fit the timing of the porbeagle time-series by adopting the annual band-pair interpretation. To provide a more comprehensive basis for valid aging criteria and a definitive growth function for the shortfin mako, more radiocarbon assays were required. The goal of our research was to take heed of this suggestion and continue the use of bomb radiocarbon to validate the aging of the shortfin mako, and specifically to resolve the validity of either annual or biannual band-pair age interpretations.

  18. Benthic substrate classification map: Gulf Islands National Seashore

    USGS Publications Warehouse

    Lavoie, Dawn; Flocks, James; Twichell, Dave; Rose, Kate

    2013-01-01

    The 2005 hurricane season was devastating for the Mississippi Gulf Coast. Hurricane Katrina caused significant degradation of the barrier islands that compose the Gulf Islands National Seashore (GUIS). Because of the ability of coastal barrier islands to help mitigate hurricane damage to the mainland, restoring these habitats prior to the onset of future storms will help protect the islands themselves and the surrounding habitats. During Hurricane Katrina, coastal barrier islands reduced storm surge by approximately 10 percent and moderated wave heights (Wamsley and others, 2009). Islands protected the mainland by preventing ocean waves from maintaining their size as they approached the mainland. In addition to storm protection, it is advantageous to restore these islands to preserve the cultural heritage present there (for example, Fort Massachusetts) and because of the influence that these islands have on marine ecology. For example, these islands help maintain a salinity regime favorable to oysters in the Mississippi Sound and provide critical habitats for many migratory birds and endangered species such as sea turtles (Chelonia mydas, Caretta caretta, and Dermochelys coriacea), Gulf sturgeon (Acipenser oxyrinchus desotoi), and piping plovers (Charadrius melodus) (U.S. Army Corps of Engineers, 2009a). As land manager for the GUIS, the National Park Service (NPS) has been working with the State of Mississippi and the Mobile District of the U.S. Army Corps of Engineers to provide a set of recommendations to the Mississippi Coastal Improvements Program (MsCIP) that will guide restoration planning. The final set of recommendations includes directly renourishing both West Ship Island (to protect Fort Massachusetts) and East Ship Island (to restore the French Warehouse archaeological site); filling Camille Cut to recreate a continuous Ship Island; and restoring natural regional sediment transport processes by placing sand in the littoral zone just east of Petit Bois

  19. Acute toxicity of TFM and a TFM/niclosamide mixture to selected species of fish, including lake sturgeon (Acipenser fulvescens) and mudpuppies (Necturus maculosus), in laboratory and field exposures

    USGS Publications Warehouse

    Boogaard, M.A.; Bills, T.D.; Johnson, D.A.

    2003-01-01

    The toxicity of the lampricides 3-trifluoromethyl-4-nitrophenol (TFM) and 2',5-dichloro-4'-nitrosalicylanilide (niclosamide) to non-target fishes has been a major point of concern since their use to control larval sea lamprey (Petromyzon marinus) populations began in the early 1960s. The toxicity of TFM to several non-target fish species has been demonstrated in previous studies. However, little information is available on the toxicity of the TFM/1% niclosamide mixture. One species of particular concern is the lake sturgeon (Acipenser fulvescens). Juvenile lake sturgeon of several size ranges were exposed to determine potential effects of the lampricides to individuals present in treatment streams. Sac fry were most resistant to the lampricides followed by fingerlings in the 200 to 225 mm size range. Swim-up fry and fingerlings less than 100 mm were the most sensitive. Concentrations that produced 50% mortality (LC50s) in juvenile lake sturgeon of these smaller size ranges were at or near the minimum lethal concentrations (MLCs) required for effective control of larval sea lampreys. The mudpuppy (Necturus maculosus), an amphibian native to several tributaries of the Great Lakes, have also become a species of interest in recent years. Laboratory tests conducted with TFM and a TFM/1% niclosamide mixture on adult mudpuppies indicate that although the amphibian is sensitive to the lampricides, an adequate margin of safety exists for adult mudpuppies to survive when exposed during stream treatments. Fifteen other fish species native to streams treated with lampricides were investigated in the laboratory to determine their sensitivity to the lampricides. Centrarchids, bluegill (Lepomis macrochirus) and green sunfish (Lepomis cyanellus) were the least sensitive to TFM, while ictalurids, black bullhead (Ictalurus melas), channel catfish (Ictalurus punctatus), and tadpole madtom (Notorus gyrinus) were the most sensitive. On-site bioassays conducted before lampricide

  20. Acute toxicity of TFM and a TFM/niclosamide mixture to selected species of fish, including lake sturgeon (Acipenser fulvescens) and mudpuppies (Necturus maculosus), in laboratory and field exposures

    USGS Publications Warehouse

    Boogaard, M.A.; Bills, T.D.; Johnson, D.A.

    2003-01-01

    The toxicity of the lampricides 3-trifluoromethyl-4-nitrophenol (TFM) and 2???,5-dichloro-4???-nitrosalicylanilide (niclosamide) to non-target fishes has been a major point of concern since their use to control larval sea lamprey (Petromyzon marinus) populations began in the early 1960s. The toxicity of TFM to several non-target fish species has been demonstrated in previous studies. However, little information is available on the toxicity of the TFM/1 % niclosamide mixture. One species of particular concern is the lake sturgeon (Acipenser fulvescens). Juvenile lake sturgeon of several size ranges were exposed to determine potential effects of the lampricides to individuals present in treatment streams. Sac fry were most resistant to the lampricides followed by fingerlings in the 200 to 225 mm size range. Swim-up fry and fingerlings less than 100 mm were the most sensitive. Concentrations that produced 50% mortality (LC50s) in juvenile lake sturgeon of these smaller size ranges were at or near the minimum lethal concentrations (MLCs) required for effective control of larval sea lampreys. The mudpuppy (Necturus maculosus), an amphibian native to several tributaries of the Great Lakes, have also become a species of interest in recent years. Laboratory tests conducted with TFM and a TFM/1 % niclosamide mixture on adult mudpuppies indicate that although the amphibian is sensitive to the lampricides, an adequate margin of safety exists for adult mudpuppies to survive when exposed during stream treatments. Fifteen other fish species native to streams treated with lampricides were investigated in the laboratory to determine their sensitivity to the lampricides. Centrarchids, bluegill (Lepomis macrochirus) and green sunfish (Lepomis cyanellus) were the least sensitive to TFM, while ictalurids, black bullhead (Ictalurus melas), channel catfish (Ictalurus punctatus), and tadpole madtom (Notorus gyrinus) were the most sensitive. On-site bioassays conducted before lampricide

  1. Effects of dietary arabinoxylan-oligosaccharides (AXOS) and endogenous probiotics on the growth performance, non-specific immunity and gut microbiota of juvenile Siberian sturgeon (Acipenser baerii).

    PubMed

    Geraylou, Zahra; Souffreau, Caroline; Rurangwa, Eugene; De Meester, Luc; Courtin, Christophe M; Delcour, Jan A; Buyse, Johan; Ollevier, Frans

    2013-09-01

    We investigated the effects of administration of putative endogenous probiotics Lactococcus lactis spp. lactis or Bacillus circulans, alone and in combination with arabinoxylan-oligosaccharides (AXOS), a new class of candidate prebiotics, in juvenile Siberian sturgeon (Acipenser baerii). Eight experimental diets were tested: basal diet (Diet 1), basal diet supplemented with 2% AXOS (Diet 2), or L. lactis ST G81 (Diet 3), L. lactis ST G45 (Diet 4), B. circulans ST M53 (Diet 5), L. lactis ST G81 + 2% AXOS (Diet 6), L. lactis ST G45 + 2% AXOS (Diet 7), B. circulans ST M53 + 2% AXOS (Diet 8). After four weeks, growth performance and feed conversion ratio significantly improved in fish fed diet 7. Innate immune responses of fish were boosted with both AXOS and probiotic diets, however synergistic effects of AXOS and probiotic diets were only observed for phagocytic and alternative complement activity. Phagocytic and respiratory burst activity of fish macrophage increased in fish fed diet 2 and 7, while humoral immune responses only increased in fish fed diet 7. Pyrosequencing analysis (16S rDNA) of the hindgut microbiota demonstrated that AXOS improved the colonization or/and growth capacity of L. lactis, as a higher relative abundance of L. lactis was observed in fish receiving diet 7. However, no observable colonization of B. circulans was found in the hindgut of fish fed diet 5 or 8, containing this bacterium. The dietary L. lactis ST G45 + 2% AXOS caused significant alterations in the intestinal microbiota by significantly decreasing in bacterial diversity, demonstrated by the fall in richness and Shannon diversity, and improved growth performance and boosted immune responses of Siberian sturgeon.

  2. Food habits of Atlantic sturgeon off the central New Jersey coast

    USGS Publications Warehouse

    Johnson, J.H.; Dropkin, D.S.; Warkentine, B.E.; Rachlin, J.W.; Andrews, W.D.

    1997-01-01

    Limited information exists on the marine diet of the Atlantic sturgeon Acipenser oxyrinchus oxyrinchus. We examined the food habits of 275 Atlantic sturgeon (total length, 106-203 cm) caught in the commercial fishery off the coast of New Jersey. Stomachs were provided by fishermen. Significantly more stomachs were empty in the spring than in the fall. Sand and organic debris were a major component in the stomachs (26.3-75.4% by weight). Polycheates were the primary pre group consumed, although the isopod Politolana conchorum was the most important individual prey eaten. Mollusks and fish contributed little to the diet. Some prey taxa (i.e., polychaetes, isopods, amphipods) exhibited seasonal variation in importance in the diet of Atlantic sturgeon. Identification of the offshore diet of Atlantic sturgeon is an important step in developing a better understanding of the life history requirements and marine ecology of this species.

  3. A RING finger protein 114 (RNF114) homolog from Chinese sturgeon (Acipenser sinensis) possesses immune-regulation properties via modulating RIG-I signaling pathway-mediated interferon expression.

    PubMed

    Liao, Zhiyong; Chen, Xiaojun; Nie, Dongsong; Wang, Jiajia; Wu, Mingjiang

    2014-12-01

    Ubiquitin ligases play important roles in immune regulation. The human RNF114 (RING finger protein 114), an ubiquitin ligase, was recently reported to be involved in immune response to double-stranded RNA in disease pathogenesis. Here, we identified a RNF114 homolog in Chinese sturgeon (Acipenser sinensis) and investigated its potential role in immune response. The full-length cDNA of Chinese sturgeon RNF114 (csRNF114) contains an open reading frame (ORF) of 681 nucleotides coding a protein of 227 amino acids. csRNF114 shares the highest identity of 76% at amino acid level to other RNF114 homologs, clustering with bony fish RNF114s based on phylogenetic analysis. The main structural features of csRNF114, including a C3HC4 (Cys3-His-Cys4) RING domain, a C2HC (Cys2-His-Cys)-type zinc finger motif, a C2H2 (Cys2-His2)-type zinc finger motif, and a UIM (ubiquitin-interacting motif), take csRNF114 as an ubiquitin ligase. csRNF114 mRNA was widely expressed in various tissues and significantly up-regulated in poly(I:C)-treated Chinese sturgeon. Over-expression of csRNF114 in HEK293T cells significantly promoted both basal and poly(I:C)-induced activation of interferon regulatory transcription factor 3 (IRF3) and nuclear factor-κB (NF-κB) downstream retinoic acid inducible gene I (RIG-I) signaling pathway and expression of target genes type I interferon (IFN), which was nearly abolished by knockdown of RIG-I with specific human siRNA and by mutation of the C3HC4 RING domain (C28A/C31A) in csRNF114 as well. Furthermore, csRNF114 associated with ubiquitinated proteins in HEK293T cells, for which the C3HC4 RING domain was essential. These data suggested that an ubiquitin ligase RNF114 homolog with a potential role in antiviral response possibly through modulating RIG-I signaling pathway was cloned from Chinese sturgeon, which might contribute to our understanding of the immune biology of Chinese sturgeon.

  4. Effects of Dietary Garlic Extracts on Whole Body Amino Acid and Fatty Acid Composition, Muscle Free Amino Acid Profiles and Blood Plasma Changes in Juvenile Sterlet Sturgeon, Acipenser ruthenus.

    PubMed

    Lee, Dong-Hoon; Lim, Seong-Ryul; Ra, Chang-Six; Kim, Jeong-Dae

    2012-10-01

    A series of studies were carried out to investigate the supplemental effects of dietary garlic extracts (GE) on whole body amino acids, whole body and muscle free amino acids, fatty acid composition and blood plasma changes in 6 month old juvenile sterlet sturgeon (Acipenser ruthenus). In the first experiment, fish with an average body weight of 59.6 g were randomly allotted to each of 10 tanks (two groups of five replicates, 20 fish/tank) and fed diets with (0.5%) or without (control) GE respectively, at the level of 2% of fish body weight per day for 5 wks. Whole body amino acid composition between the GE and control groups were not different (p>0.05). Among free amino acids in muscle, L-glutamic acid, L-alanine, L-valine, L-leucine and L-phenylalanine were significantly (p<0.05) higher in GE than in control. However, total whole body free amino acids were significantly lower in GE than in control (p<0.05). GE group showed higher EPA (C22:6n3) and DHA (C22:5n3) in their whole body than the other group (p<0.05). In the second experiment, the effects of dietary garlic extracts on blood plasma changes were investigated using 6 month old juvenile sterlet sturgeon averaging 56.5 g. Fish were randomly allotted to each of 2 tanks (300 fish/tank) and fed diets with (0.5%) or without (control) GE respectively, at the rate of 2% of body weight per day for 23 d. At the end of the feeding trial, blood was taken from the tail vein (n = 5, per group) at 1, 12, and 24 h after feeding, respectively. Blood plasma glucose, insulin and the other serological characteristics were also measured to assess postprandial status of the fish. Plasma glucose concentrations (mg/dl) between two groups (GE vs control) were significantly (p< 0.05) different at 1 (50.8 vs 62.4) and 24 h (57.6 vs 73.6) after feeding, respectively, while no significant difference (p>0.05) were noticed at 12 h (74.6 vs 73.0). Plasma insulin concentrations (μIU/ml) between the two groups were significantly (p<0

  5. Functionality of aryl hydrocarbon receptors (AhR1 and AhR2) of white sturgeon (Acipenser transmontanus) and implications for the risk assessment of dioxin-like compounds.

    PubMed

    Doering, Jon A; Farmahin, Reza; Wiseman, Steve; Kennedy, Sean W; Giesy, John P; Hecker, Markus

    2014-07-15

    Worldwide, populations of sturgeons are endangered, and it is hypothesized that anthropogenic chemicals, including dioxin-like compounds (DLCs), might be contributing to the observed declines in populations. DLCs elicit their toxic action through activation of the aryl hydrocarbon receptor (AhR), which is believed to regulate most, if not all, adverse effects associated with exposure to these chemicals. Currently, risk assessment of DLCs in fishes uses toxic equivalency factors (TEFs) developed for the World Health Organization (WHO) that are based on studies of embryo-lethality with salmonids. However, there is a lack of knowledge of the sensitivity of sturgeons to DLCs, and it is uncertain whether TEFs developed by the WHO are protective of these fishes. Sturgeons are evolutionarily distinct from salmonids, and the AhRs of sturgeons differ from those of salmonids. Therefore, this study investigated the sensitivity of white sturgeon (Acipenser transmontanus) to DLCs in vitro via the use of luciferase reporter gene assays using COS-7 cells transfected with AhR1 or AhR2 of white sturgeon. Specifically, activation and relative potencies (RePs) of 2,3,7,8-tetrachloro-dibenzo-p-dioxin (TCDD), 2,3,4,7,8-pentachloro-dibenzofuran, 2,3,7,8-tetrachloro-dibenzofuran, 3,3',4,4',5-pentachlorobiphenyl, 3,3',4,4'-tetrachlorobiphenyl, and 2,3,3',4,4'-pentachlorobiphenyl were determined for each AhR. It was demonstrated that white sturgeon expresses AhR1s and AhR2s that are both activated by DLCs with EC50 values for 2,3,7,8-TCDD that are lower than those of any other AhR of vertebrates tested to date. Both AhRs of white sturgeon had RePs for polychlorinated dibenzofurans more similar to TEFs for birds, while RePs for polychlorinated biphenyls were most similar to TEFs for fishes. Measured concentrations of select DLCs in tissues of white sturgeon from British Columbia, Canada, were used to calculate toxic equivalents (TEQs) by use of TEFs for fishes used by the WHO and TCDD

  6. Identification and expression of aryl hydrocarbon receptors (AhR1 and AhR2) provide insight in an evolutionary context regarding sensitivity of white sturgeon (Acipenser transmontanus) to dioxin-like compounds.

    PubMed

    Doering, Jon A; Wiseman, Steve; Beitel, Shawn C; Giesy, John P; Hecker, Markus

    2014-05-01

    Sturgeons are ancient fishes, which are endangered in many parts of the world. Due to their benthic nature and longevity, sturgeon are at great risk of exposure to bioaccumulative contaminants such as dioxin-like compounds (DLCs). Despite their endangered status, little research has been conducted to characterize the relative sensitivity of sturgeons to DLCs. Proper assessment of risk of DLCs posed to these fishes therefore, requires a better understanding of this sensitivity and the factors that are driving it. Adverse effects associated with exposure to DLCs are mediated by the aryl hydrocarbon receptor (AhR). This study identified and characterized two distinct AhRs, AhR1 and AhR2, in white sturgeon (Acipenser transmontanus) for the first time as a first step in studying the relative sensitivities of sturgeons to DLCs. Furthermore, tissue-specific expression of both AhRs under basal conditions and in response to exposure to the model DLC, β-naphthoflavone (βNF), was determined. The sequence of amino acids of AhR1 of white sturgeon had greater similarity to AhRs of tetrapods, including amphibians, birds, and mammals, than to AhR1s of other fishes. The sequence of amino acids in the ligand binding domain of the AhR1 had greater than 80% similarity to AhRs known to bind DLCs and was less similar to AhRs not known to bind DLCs. AhR2 of white sturgeon had greatest similarity to AhR2 of other fishes. Profiles of expression of AhR1 and AhR2 in white sturgeon were distinct from those known in other fishes and appear more similar to profiles observed in birds. Expressions of both AhR1 and AhR2 of white sturgeon were greatest in liver and heart, which are target organs for DLCs. Furthermore, abundances of transcripts of AhR1 and AhR2 in all tissues from white sturgeon were greater than controls (up to 35-fold) following exposure to βNF. Based upon both AhRs having similar abundances of transcript in target organs of DLC toxicity, both AhRs being up-regulated following

  7. Stable Carbon Isotope Evidence for Reduced Feeding of Gulf of Mexico Sturgeon during Their Prolonged River Residence Period

    NASA Astrophysics Data System (ADS)

    Gu, B.; Schell, D. M.; Frazer, T.; Hoyer, M.; Chapman, F. A.

    2001-09-01

    Stable carbon isotope ratios were used to delineate food sources for Gulf of Mexico sturgeon ( Acipenser oxyrinchus de sotoi), an anadromous fish that migrates between Gulf of Mexico and the coastal rivers in south-east U.S.A. The large difference in isotope ratios (˜11‰) between freshwater food sources and fish muscle tissue suggests that the Gulf of Mexico sturgeon do not feed significantly in fresh waters. Isotope ratio data from this study and also from the literature indicate that the growth of Gulf of Mexico sturgeon is almost entirely supported by coastal marine food sources. It is likely that Gulf of Mexico sturgeon use the cool springs that seep into the river as a thermal refuge during their river residence in summer and that thermal barriers may prevent the fish from exploiting the rich food sources available in the warmer portions of the Suwannee River.

  8. When the American sea sturgeon swam east.

    PubMed

    Ludwig, Arne; Debus, Lutz; Lieckfeldt, Dietmar; Wirgin, Isaac; Benecke, Norbert; Jenneckens, Ingo; Williot, Patrick; Waldman, John R; Pitra, Christian

    2002-10-03

    The two species of Atlantic sea sturgeon on either shore of the North Atlantic, Acipenser sturio in Europe and A. oxyrinchus in North America, probably diverged with the closure of the Tethys Sea and the onset of the North Atlantic Gyre 15-20 million years ago, and contact between them was then presumably precluded by geographic distance. Here we present genetic, morphological and archaeological evidence indicating that the North American sturgeon colonized the Baltic during the Middle Ages and replaced the native sturgeon there, before recently becoming extinct itself in Europe as a result of human activities. In addition to representing a unique transatlantic colonization event by a fish that swims upriver to spawn, our findings have important implications for projects aimed at restocking Baltic waters with the European sturgeon.

  9. Seasonal Distribution and Movements of Atlantic and Shortnose Sturgeon in the Penobscot River Estuary, Maine

    USGS Publications Warehouse

    Zydlewski, Joseph; Fernandes, Stephen J.; Zydlewski, Gayle B.; Wippelhauser, Gail S.; Kinnison, Michael T.

    2016-01-01

    Relatively little is known about the distribution and seasonal movement patterns of shortnose sturgeon Acipenser brevirostrum and Atlantic sturgeon Acipenser oxyrinchus oxyrinchus occupying rivers in the northern part of their range. During 2006 and 2007, 40 shortnose sturgeon (66–113.4 cm fork length [FL]) and 8 Atlantic sturgeon (76.2–166.2 cm FL) were captured in the Penobscot River, Maine, implanted with acoustic transmitters, and monitored using an array of acoustic receivers in the Penobscot River estuary and Penobscot Bay. Shortnose sturgeon were present year round in the estuary and overwintered from fall (mid-October) to spring (mid-April) in the upper estuary. In early spring, all individuals moved downstream to the middle estuary. Over the course of the summer, many individuals moved upstream to approximately 2 km of the downstream-most dam (46 river kilometers [rkm] from the Penobscot River mouth [rkm 0]) by August. Most aggregated into an overwintering site (rkm 36.5) in mid- to late fall. As many as 50% of the tagged shortnose sturgeon moved into and out of the Penobscot River system during 2007, and 83% were subsequently detected by an acoustic array in the Kennebec River, located 150 km from the Penobscot River estuary. Atlantic sturgeon moved into the estuary from the ocean in the summer and concentrated into a 1.5-km reach. All Atlantic sturgeon moved to the ocean by fall, and two of these were detected in the Kennebec River. Although these behaviors are common for Atlantic sturgeon, regular coastal migrations of shortnose sturgeon have not been documented previously in this region. These results have important implications for future dam removals as well as for rangewide and river-specific shortnose sturgeon management.

  10. Dual Annual Spawning Races in Atlantic Sturgeon

    PubMed Central

    Balazik, Matthew T.; Musick, John A.

    2015-01-01

    Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus, Acipenseridae) populations in the United States were listed as either endangered or threatened under the Endangered Species Act in 2012. Because of the endangered/threatened status, a better understanding of Atlantic sturgeon life-history behavior and habitat use is important for effective management. It has been widely documented that Atlantic sturgeon reproduction occurs from late winter to early summer, varying clinally with latitude. However, recent data show Atlantic sturgeon also spawn later in the year. The group that spawns later in the year seems to be completely separate from the spring spawning run. Recognition of the later spawning season has drastically modified estimates of the population status of Atlantic sturgeon in Virginia. With the combination of new telemetry data and historical documentation we describe a dual spawning strategy that likely occurs in various degrees along most, if not all, of the Atlantic sturgeon's range. Using new data combined with historical sources, a new spawning strategy emerges which managers and researchers should note when determining the status of Atlantic sturgeon populations and implementing conservation measures. PMID:26020631

  11. Dual annual spawning races in Atlantic sturgeon.

    PubMed

    Balazik, Matthew T; Musick, John A

    2015-01-01

    Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus, Acipenseridae) populations in the United States were listed as either endangered or threatened under the Endangered Species Act in 2012. Because of the endangered/threatened status, a better understanding of Atlantic sturgeon life-history behavior and habitat use is important for effective management. It has been widely documented that Atlantic sturgeon reproduction occurs from late winter to early summer, varying clinally with latitude. However, recent data show Atlantic sturgeon also spawn later in the year. The group that spawns later in the year seems to be completely separate from the spring spawning run. Recognition of the later spawning season has drastically modified estimates of the population status of Atlantic sturgeon in Virginia. With the combination of new telemetry data and historical documentation we describe a dual spawning strategy that likely occurs in various degrees along most, if not all, of the Atlantic sturgeon's range. Using new data combined with historical sources, a new spawning strategy emerges which managers and researchers should note when determining the status of Atlantic sturgeon populations and implementing conservation measures.

  12. Capture locations and growth rates of Atlantic sturgeon in the Chesapeake Bay

    USGS Publications Warehouse

    Welsh, S.A.; Eyler, S.M.; Mangold, M.F.; Spells, A.J.

    2002-01-01

    Little information exists on temporal and spatial distributions of wild and hatchery-reared Atlantic sturgeon Acipenser oxyrinchus oxyrinchus in the Chesapeake Bay. Approximately 3,300 hatchery-reared Atlantic sturgeon comprised of two size groups were released into the Nanticoke River, a tributary of the Chesapeake Bay, on 8 July 1996. During January 1996-May 2000, 1099 Atlantic sturgeon were captured incidentally (i.e., bycatch) by commercial watermen in the Chesapeake Bay, including 420 hatchery-reared individuals. Wild and hatchery-reared Atlantic sturgeon were captured primarily in pound nets and gill nets. Biologists tagged each fish and recorded weight, length, and location of capture. Although two adults greater than 2000 mm fork length (FL) were captured in Maryland waters, wild sturgeon were primarily juveniles from Maryland and Virginia waters (415 and 259 individuals below 1000 mm FL, respectively). A growth rate of 0.565 mm/d (N = 15, SE = 0.081) was estimated for wild individuals (487-944 mm TL at release) at liberty from 30 to 622 d. The average growth of the group of hatchery-reared Atlantic sturgeon raised at 10??C exceeded that of the group raised at 17??C. Our distributional data based on capture locations are biased by fishery dependence and gear selectivity. These data are informative to managers, however, because commercial effort is widely distributed in the Chesapeake Bay, and little distributional data were available before this study.

  13. Potential for restoration of the Roanoke River population of Atlantic sturgeon

    USGS Publications Warehouse

    Armstrong, J.L.; Hightower, J.E.

    2002-01-01

    The Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) was historically abundant within Albemarie Sound and the Roanoke River in North Carolina, but declined dramatically in the late 1800s in response to intensive fishing. Recent evidence suggests that the population may be recovering, following a statewide prohibition on harvest in 1991. A recruitment index generally increased from 1992 through 2001. Estuarine habitat for juveniles appears to be suitable, resulting in mean growth rates for age 1 fish ranging from 0.59 to 0.81 mm day-1. A restoration goal of 7000-21 000 subadult and adult Atlantic sturgeon was developed for the Roanoke River, based on historical landings records. Bycatch mortality because of commercial gill-netting in Albermarle Sound could affect recovery. Telemetry and netting data indicate that juvenile Atlantic sturgeon in the sound are most abundant in shallow nearshore areas where commercial gill-netting is concentrated. However, immediate mortality rates from survey and commercial gill-netting in Albemarle Sound were only 0-2%. Additional field studies are needed to refine estimates of immediate- and longer-term mortality associated with gill-net bycatch.

  14. Fall spawning of Atlantic sturgeon in the Roanoke River, North Carolina

    USGS Publications Warehouse

    Smith, Joseph A.; Hightower, Joseph E.; Flowers, H. Jared

    2015-01-01

    In 2012, the National Oceanic and Atmospheric Administration (NOAA) declared Atlantic Sturgeon Acipenser oxyrinchus oxyrinchus to be threatened or endangered throughout its range in U.S. waters. Restoration of the subspecies will require much new information, particularly on the location and timing of spawning. We used a combination of acoustic telemetry and sampling with anchored artificial substrates (spawning pads) to detect fall (September–November) spawning in the Roanoke River in North Carolina. This population is included in the Carolina Distinct Population Segment, which was classified by NOAA as endangered. Sampling was done immediately below the first shoals encountered by anadromous fishes, near Weldon. Our collection of 38 eggs during the 21 d that spawning pads were deployed appears to be the first such collection (spring or fall) for wild-spawned Atlantic Sturgeon eggs. Based on egg development stages, estimated spawning dates were September 17–18 and 18–19 at water temperatures from 25.3°C to 24.3°C and river discharge from 55 to 297 m3/s. These observations about fall spawning and habitat use should aid in protecting critical habitats and planning research on Atlantic Sturgeon spawning in other rivers.

  15. Histopathological alterations of juvenile green (Acipenser medirostris) and white sturgeon (Acipenser transmontanus) exposed to graded levels of dietary methylmercury.

    PubMed

    Lee, Jang-Won; Kim, Jae-Won; De Riu, Nicola; Moniello, Giuseppe; Hung, Silas S O

    2012-03-01

    Triplicate groups of juvenile green and white sturgeon (average weight of 30 ± 2 g) were exposed to one of four concentrations of dietary methylmercury (MeHg; 0, 25, 50, and 100 mg MeHg/kg diet) for 8 weeks to determine and compare the sensitivity of the two sturgeon species from a histopathological perspective. After 4- and 8-week exposure, histological changes were examined in the kidney, liver, gill, skeletal muscle, and heart muscle of both species using light microscopy. Marked abnormalities were observed in the kidney and liver of both sturgeon species after each exposure period; the abnormalities showed progressive histological alterations in severity with increasing doses and duration of exposure. Renal lesions included tubular epithelium degeneration and necrosis, renal corpuscular disintegration, and interstitial tissue degeneration. The changes observed in the livers of both sturgeon species were glycogen depletion and vacuolar degeneration. In the gill and skeletal and heart muscle of green and white sturgeon fed MeHg-added diets, mild histological changes were observed but did not show pronounced difference between the two species. Although the lowest observed effect concentration in both species was the 25 mg MeHg/kg diet, the histological changes in the kidney and liver were more pronounced at all treatments groups of green sturgeon than those of white sturgeon. The current results on structural changes of kidney and liver (i.e., more severe glycogen depletion and tubular epithelium degeneration in green sturgeon) confirmed our previous results, in that green sturgeon exhibited a higher mortality, lower growth rate, and lower protein, lipid, and energy contents in their whole body than white sturgeon under the same MeHg exposures.

  16. Shifting distributions of adult Atlantic sturgeon amidst post-industrialization and future impacts in the Delaware River: a maximum entropy approach.

    PubMed

    Breece, Matthew W; Oliver, Matthew J; Cimino, Megan A; Fox, Dewayne A

    2013-01-01

    Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) experienced severe declines due to habitat destruction and overfishing beginning in the late 19(th) century. Subsequent to the boom and bust period of exploitation, there has been minimal fishing pressure and improving habitats. However, lack of recovery led to the 2012 listing of Atlantic sturgeon under the Endangered Species Act. Although habitats may be improving, the availability of high quality spawning habitat, essential for the survival and development of eggs and larvae may still be a limiting factor in the recovery of Atlantic sturgeon. To estimate adult Atlantic sturgeon spatial distributions during riverine occupancy in the Delaware River, we utilized a maximum entropy (MaxEnt) approach along with passive biotelemetry during the likely spawning season. We found that substrate composition and distance from the salt front significantly influenced the locations of adult Atlantic sturgeon in the Delaware River. To broaden the scope of this study we projected our model onto four scenarios depicting varying locations of the salt front in the Delaware River: the contemporary location of the salt front during the likely spawning season, the location of the salt front during the historic fishery in the late 19(th) century, an estimated shift in the salt front by the year 2100 due to climate change, and an extreme drought scenario, similar to that which occurred in the 1960's. The movement of the salt front upstream as a result of dredging and climate change likely eliminated historic spawning habitats and currently threatens areas where Atlantic sturgeon spawning may be taking place. Identifying where suitable spawning substrate and water chemistry intersect with the likely occurrence of adult Atlantic sturgeon in the Delaware River highlights essential spawning habitats, enhancing recovery prospects for this imperiled species.

  17. Origin of Atlantic Sturgeon collected off the Delaware coast during spring months

    USGS Publications Warehouse

    Wirgin, Isaac; Breece, Matthew W.; Fox, Dewayne A.; Maceda, Lorraine; Wark, Kevin W.; King, Timothy L.

    2015-01-01

    Atlantic Sturgeon Acipenser oxyrinchus oxyrinchus was federally listed under the U.S. Endangered Species Act as five distinct population segments (DPS). Currently, at least 18 estuaries coastwide host spawning populations and the viability of these vary, requiring differing levels of protection. Subadults emigrate from their natal estuaries to marine waters where they are vulnerable to bycatch; one of the major threats to the rebuilding of populations. As a result, identifying the population origin of Atlantic Sturgeon in coastal waters is critical to development of management plans intended to minimize interactions of the most imperiled populations with damaging fisheries. We used mitochondrial DNA control region sequencing and microsatellite DNA analyses to determine the origin of 261 Atlantic Sturgeon collected off the Delaware coast during the spring months. Using individual-based assignment (IBA) testing and mixed stock analysis, we found that specimens originated from all nine of our reference populations and the five DPSs used in the listing determination. Using IBA, we found that the Hudson River population was the largest contributor (38.3%) to our coastal collection. The James (19.9%) and Delaware (13.8%) river populations, at one time thought to be extirpated or nearly so, were the next largest contributors. The three populations combined in the South Atlantic DPS contributed 21% of specimens; the Altamaha River, the largest population in the South Atlantic DPS, only contributed a single specimen to the collection. While the origin of specimens collected on the Delaware coast was most likely within rivers of the New York Bight DPS (52.1%), specimens that originated elsewhere were also well represented. Genetic analyses provide a robust tool to identify the population origin of individual sturgeon outside of their natal estuaries and to determine the quantitative contributions of individual populations to coastal aggregations that are vulnerable to

  18. Characterization and expression of cytochrome P4501A in Atlantic sturgeon and shortnose sturgeon experimentally exposed to coplanar PCB 126 and TCDD.

    PubMed

    Roy, Nirmal K; Walker, Nichole; Chambers, R Christopher; Wirgin, Isaac

    2011-07-01

    The AHR pathway activates transcription of CYP1A and mediates most toxic responses from exposure to halogenated aromatic hydrocarbon contaminants such as PCBs and PCDD/Fs. Therefore, expression of CYP1A is predictive of most higher level toxic responses from these chemicals. To date, no study had developed an assay to quantify CYP1A expression in any sturgeon species. We addressed this deficiency by partially characterizing CYP1A in Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) and shortnose sturgeon (Acipenser brevirostrum) and then used derived sturgeon sequences to develop reverse transcriptase (RT)-PCR assays to quantify CYP1A mRNA expression in TCDD and PCB126 treated early life-stages of both species. Phylogenetic analysis of CYP1A, CYP1B, CYP1C and CYP3A deduced amino acid sequences from other fishes and sturgeons revealed that our putative Atlantic sturgeon and shortnose sturgeon CYP1A sequences most closely clustered with previously derived CYP1A sequences. We then used semi-quantitative and real-time RT-PCR to measure CYP1A mRNA levels in newly hatched Atlantic sturgeon and shortnose sturgeon larvae that were exposed to graded doses of waterborne PCB126 (0.01-1000 parts per billion (ppb)) and TCDD (0.001-10 ppb). We initially observed significant induction of CYP1A mRNA compared to vehicle control at the lowest doses of PCB126 and TCDD used, 0.01 ppb and 0.001 ppb, respectively. Significant induction was observed at all doses of both chemicals although lower expression was seen at the highest doses. We also compared CYP1A expression among tissues of i.p. injected shortnose sturgeon and found significant inducibility in heart, intestine, and liver, but not in blood, gill, or pectoral fin clips. For the first time, our results indicate that young life-stages of sturgeons are sensitive to AHR ligands at environmentally relevant concentrations, however, it is yet to be determined if induction of CYP1A can be used as a biomarker in environmental

  19. Toxic effects of PCB126 and TCDD on shortnose sturgeon and Atlantic sturgeon.

    PubMed

    Chambers, R Christopher; Davis, Dawn D; Habeck, Ehren A; Roy, Nirmal K; Wirgin, Isaac

    2012-10-01

    Exposure to chemical contaminants is often invoked to explain recruitment failures to populations of sturgeon worldwide, but there is little empirical evidence to support the idea that young sturgeon are sensitive at environmentally relevant concentrations. The authors used shortnose sturgeon (Acipenser brevirostum) and Atlantic sturgeon (Acipenser oxyrinchus) as models to investigate the sensitivities of sturgeon to early-life-stage toxicities from embryonic exposures to graded doses of polychlorinated biphenyl 126 (PCB126) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Survival to hatching of shortnose sturgeon decreased with increasing dose, although the duration of the embryonic period was not significantly altered by exposure in either species. Morphometric features of larvae of both species were affected by dose, including shortening of the body, reduction in head size, reduction in quantity of yolk reserves, and reduction in eye size. Eye development in both species was delayed with increasing dose for both chemicals. The persistence of larvae in a food-free environment decreased inversely with dose in both species, with sharp declines occurring at PCB126 and TCDD doses of ≥1 ppb and ≥0.1 ppb, respectively. Dose-responsive early-life-stage toxicities reported here are among the more sensitive found in fish and occurred at burdens similar to those found in situ in a sympatric bottom-dwelling bony fish in the Hudson River Estuary. The present study is among the first demonstrating the sensitivity of any sturgeon to the hallmark early-life-stage toxicities induced by aryl hydrocarbon receptor agonists.

  20. TOXIC EFFECTS OF PCB126 AND TCDD ON SHORTNOSE STURGEON AND ATLANTIC STURGEON

    PubMed Central

    Chambers, R. Christopher; Davis, Dawn D.; Habeck, Ehren A.; Roy, Nirmal K.

    2014-01-01

    Exposure to chemical contaminants is often invoked to explain recruitment failures to populations of sturgeon worldwide, but there is little empirical evidence to support the idea that young sturgeon are sensitive at environmentally relevant concentrations. The authors used shortnose sturgeon (Acipenser brevirostum) and Atlantic sturgeon (Acipenser oxyrinchus) as models to investigate the sensitivities of sturgeon to early-life-stage toxicities from embryonic exposures to graded doses of polychlorinated biphenyl 126 (PCB126) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Survival to hatching of shortnose sturgeon decreased with increasing dose, although the duration of the embryonic period was not significantly altered by exposure in either species. Morphometric features of larvae of both species were affected by dose, including shortening of the body, reduction in head size, reduction in quantity of yolk reserves, and reduction in eye size. Eye development in both species was delayed with increasing dose for both chemicals. The persistence of larvae in a food-free environment decreased inversely with dose in both species, with sharp declines occurring at PCB126 and TCDD doses of ≥1 ppb and ≥0.1 ppb, respectively. Dose-responsive early-life-stage toxicities reported here are among the more sensitive found in fish and occurred at burdens similar to those found in situ in a sympatric bottom-dwelling bony fish in the Hudson River Estuary. The present study is among the first demonstrating the sensitivity of any sturgeon to the hallmark early-life-stage toxicities induced by aryl hydrocarbon receptor agonists. PMID:22825886

  1. [Unidirectional Hybridization of Kaluga Acipenser dauricus Georgi, 1775 and Amur Sturgeon Acipenser schrenckii Brandt, 1869, Inferred from the Mitochondrial DNA Genotyping of Their Natural Hybrids].

    PubMed

    Shedko, S V; Shedko, M B

    2016-03-01

    In 2009 through 2011, among 730 individuals of kaluga and Amur sturgeon collected in the lower reaches of the Amur River and the Amursky Liman, 17 morphologically intermediate individuals (hybrids) with the body length of 56 to 202 cm (median, 81 cm) were identified, including 11 individuals (4.6%) found in 2009, three individuals (1.6%) found in 2010, and three individuals (1.1%), in 2011. In 16 hybrids 819 bp of the mtDNA control regions were sequences and 11 haplotypes were identified. Since all these haplotypes were from the mtDNA lineages of kaluga, it was concluded that hybridization occurred in one direction, kaluga (♀) x Amur sturgeon (♂). This asymmetry could be caused by the large difference in sizes of these species. Since the earlier examined morphologically typical Amur sturgeons showed the absence of alien haplotypes (Shedko, et al., 2015), the absence of the mtDNA introgression is claimed. This can be caused by low viability or sterility of the backcross females (kaluga (♀) x Amur sturgeon (♂)) x Amur sturgeon (♂). The samples of hybrids and typical kaluga individuals demonstrated no differences in the frequency spectra of the mtDNA haplotypes. However, haplotype and nucleotide diversity in the first sample was somewhat higher than in the second one (0.950 versus 0.927 and 0.0054 versus 0.0044, respectively). The data obtained will be useful for population monitoring of kaluga and Amur sturgeon, Amur River endemics, which are classified as critically endangered by the IUCN Red List of Threatened Species.

  2. A novel approach to fitting the von Bertalanffy relationship to a mixed stock of Atlantic sturgeon harvested off the New Jersey Coast

    USGS Publications Warehouse

    Johnson, James H.; McKenna, James E.; Dropkin, David S.; Andrews, William D.

    2005-01-01

    We examined the growth characteristics of 303 Atlantic sturgeon, Acipenser oxyrinchus, caught in the commercial fishery off the New Jersey coast from 1992 to 1994 (fork length range: 93–219 cm). Sections taken from the leading pectoral fin ray were used to age each sturgeon. Ages ranged from 5–26 years. Von Bertalanffy growth models for males and females fit well, but test statistics (t-test, maximum likelihood) failed to reject the null hypothesis that growth was not significantly different between sexes. Consequently, all data were pooled and the combined data gave L∞ and K estimates of 174.2 cm and 0.144, respectively. Our growth data do not fit the pattern of slower growth and increased size in more northernly latitudes for Atlantic sturgeon observed in other work. Lack of uniformity of our growth data may be due to (1) the sturgeon fishery harvesting multiple stocks having different growth rates, and (2) size limits for the commercial fishery having created a bias in estimating growth parameters.

  3. A novel approach to surveying sturgeon using side-scan sonar and occupancy modeling

    USGS Publications Warehouse

    Flowers, H. Jared; Hightower, Joseph E.

    2013-01-01

    Technological advances represent opportunities to enhance and supplement traditional fisheries sampling approaches. One example with growing importance for fisheries research is hydroacoustic technologies such as side-scan sonar. Advantages of side-scan sonar over traditional techniques include the ability to sample large areas efficiently and the potential to survey fish without physical handling-important for species of conservation concern, such as endangered sturgeons. Our objectives were to design an efficient survey methodology for sampling Atlantic Sturgeon Acipenser oxyrinchus by using side-scan sonar and to developmethods for analyzing these data. In North Carolina and South Carolina, we surveyed six rivers thought to contain varying abundances of sturgeon by using a combination of side-scan sonar, telemetry, and video cameras (i.e., to sample jumping sturgeon). Lower reaches of each river near the saltwater-freshwater interface were surveyed on three occasions (generally successive days), and we used occupancy modeling to analyze these data.We were able to detect sturgeon in five of six rivers by using these methods. Side-scan sonar was effective in detecting sturgeon, with estimated gear-specific detection probabilities ranging from 0.2 to 0.5 and river-specific occupancy estimates (per 2-km river segment) ranging from 0.0 to 0.8. Future extensions of this occupancy modeling framework will involve the use of side-scan sonar data to assess sturgeon habitat and abundance in different river systems.

  4. Estimating sturgeon abundance in the Carolinas using side-scan sonar

    USGS Publications Warehouse

    Flowers, H. Jared; Hightower, Joseph E.

    2015-01-01

    Sturgeons (Acipenseridae) are one of the most threatened taxa worldwide, including species in North Carolina and South Carolina. Populations of Atlantic Sturgeon Acipenser oxyrinchus in the Carolinas have been significantly reduced from historical levels by a combination of intense fishing and habitat loss. There is a need for estimates of current abundance, to describe status, and for estimates of historical abundance in order to provide realistic recovery goals. In this study we used N-mixture and distance models with data acquired from side-scan sonar surveys to estimate abundance of sturgeon in six major sturgeon rivers in North Carolina and South Carolina. Estimated abundances of sturgeon greater than 1 m TL in the Carolina distinct population segment (DPS) were 2,031 using the count model and 1,912 via the distance model. The Pee Dee River had the highest overall abundance of any river at 1,944 (count model) or 1,823 (distance model). These estimates do not account for sturgeon less than 1 m TL or occurring in riverine reaches not surveyed or in marine waters. Comparing the two models, the N-mixture model produced similar estimates using less data than the distance model with only a slight reduction of estimated precision.

  5. Genetic diversity, kinship analysis, and broodstock management of captive Atlantic sturgeon for population restoration

    USGS Publications Warehouse

    Henderson, A.P.; Spidle, A.P.; King, T.L.

    2005-01-01

    Captive Atlantic sturgeon Acipenser oxyrinchus considered for use as broodstock in a restoration program were genotyped using nuclear DNA microsatellites and compared to wild collections from the Hudson River, New York (source of parents of the captive sturgeon) and from Albemarle Sound, North Carolina. Because the potential broodfish were the progeny of a small number of parents, maintaining genetic diversity and minimizing inbreeding is essential to a successful breeding and supplementation program. The microsatellite loci used in this analysis generated unique multilocus genotypes for each of 136 Atlantic sturgeon. Analyses indicated significant genetic separation between the New York and North Carolina collections and correctly identified the potential broodstock as a subset of the Hudson River population. Pairwise genetic distance (-In proportion of shared alleles) between half and full siblings in the potential broodfish was as great as 1.386, a value exceeded by only 36% of the sampled broodfish pairs available for mating. Because the current broodstock population does not seem to have deviated far from their ancestral population in the Hudson River, progeny from that broodstock, or the parents themselves, would seem to be genetically suitable for release back into the Hudson River.

  6. Effects of ration and temperature on growth of age-0 Atlantic sturgeon

    USGS Publications Warehouse

    Kelly, J.L.; Arnold, D.E.

    1999-01-01

    Our objective was to gain insight into the optimum temperature and ration for growth of age-0 Atlantic sturgeon Acipenser oxyrinchus in culture. We conducted two trials, each for 8 weeks. Trial 1 started with 60-g fish, trial 2 started with 0 3-g fish. Water temperatures of 15, 17, and 19??C were used separately in each trial. Rations (dry food, wet weight of fish) for 60-g fish were 0.5, 1.0, and 1.5% of biomass per day, for 0.3-g fish, rations were 3, 5, and 7% of biomass per day. We set up three tank replicates, of equal fish biomass, at each combination of temperature and ration. The highest growth rate in trial 1 (for 60-g fish) was 0.014/d at 15??C and the 1.5% ration, although this growth rate was not significantly different from the growth rate at 17??C and 1.5% ration or at 17??C and 1.0% ration. The highest growth rate in trial 2 (for 0.3-g fish) was 0.067/d at 19??C and the 7.0% ration. Instantaneous growth at these conditions was significantly different from all other combinations of temperature and ration. Although these results may not completely define the temperature and ration under which fish could achieve maximum growth rate, they provide a solid starting point for further development of Atlantic sturgeon culture.

  7. Expression of growth hormone gene during early development of Siberian sturgeon (Acipenser baerii)

    PubMed Central

    Abdolahnejad, Zeinab; Pourkazemi, Mohammad; Khoshkholgh, Majid Reza; Yarmohammadi, Mahtab

    2015-01-01

    The mRNA expression of growth hormone (GH) gene in early development stages of Siberian sturgeon was investigated using RT-PCR method. Samples were collected from unfertilized eggs up to 50 days post hatched (dph) larvae in 11 different times. Ribosomal protein L6 (RPL6) transcripts were used as the internal standard during quantification of GH mRNA expression. The results showed that the GH mRNA could be observed in the eyed eggs and even at unfertilized eggs of Siberian sturgeon. The highest amounts of GH mRNA were found at 25 and 50 dph larvae, while the lowest levels were detected at 1 and 3 dph larvae stage. These findings suggest that, the GH mRNA play a key role during developmental stages of Siberian sturgeon. PMID:27844010

  8. Diel and seasonal movements of white sturgeon, Acipenser transmontanus, in the mid-Columbia river

    SciTech Connect

    Haynes, J.M.; Gray, R.H.

    1981-04-01

    To evaluate seasonal movements in the free-flowing Hanford reach of the Columbia River, white sturgeon with radio transmitters in spring and early summer 1977 were monitored along with fish that had been tagged in 1975 and 1976. Daily environmental temperature records indicated sturgeon did not consistently engage in a diel movement pattern. It was concluded that although temperature is a major influence stimulating seasonal movements, light cycle and feeding probably influence diel movements. (JMT)

  9. Snout dimorphism in white sturgeon, Acipenser transmontanus, from the Columbia River at Hanford, Washington

    SciTech Connect

    Crass, D.W.; Gray, R.H.

    1982-01-01

    Although differences in snout length and shape between young and adult sturgeon are known, morphological divergence in snout type of similar sized individuals has not been reported. Field observations in the Hanford reach of the Columbia River on 99 white sturgeon ranging from 35 to 205 cm total length showed two snout types based on size and shape. The occurrence of this dimorphism at Hanford may reflect isolating mechanisms, such as physical barriers which block fish movements. (RAF)

  10. [Mitochondrial DNA sequence variation, demographic history, and population structure of Amur sturgeon Acipenser schrenckii Brandt, 1869].

    PubMed

    Shedko, S V; Miroshnichenko, I L; Nemkova, G A; Koshelev, V N; Shedko, M B

    2015-02-01

    The variability of the mtDNA control region (D-loop) was examined in Amur sturgeon endemic to the Amur River. This species is also classified as critically endangered by the IUCN Red List of Threatened species. Sequencing of 796- to 812-bp fragments of the D-loop in 112 sturgeon collected in the Lower Amur revealed 73 different genotypes. The sample was characterized by a high level of haplotypic (0.976) and nucleotide (0.0194) diversity. The identified haplotypes split into two well-defined monophyletic groups, BG (n = 39) and SM (n = 34), differing (HKY distance) on average by 3.41% of nucleotide positions upon an average level of intragroup differences of 0.54 and 1.23%, respectively. Moreover, the haplotypes of the SM groups differed by the presence of a 13-14 bp deletion. Most ofthe samples (66 out of 112) carried BG haplotypes. Overall, the pattern of pairwise nucleotide differences and the results of neutrality tests, as well as the results of tests for compliance with the model of sudden demographic expansion or with the model of exponential growth pointed to a past significant increase in the number of Amur sturgeon, which was most clearly manifested in the analysis of data on the BG haplogroup. The constructed Bayesian skyline plots showed that this growth began about 18 to 16 thousand years ago. At present, the effective size of the strongly reduced (due to overharvesting) population of Amur sturgeon may be equal to or even lower than it was before the beginning of this growth during the Last Glacial Maximum. The presence in the mitochondrial gene pool ofAmur sturgeon of two haplogroups, their unequal evolutionary dynamics, and, judging by scanty data, their unequal representation in the Russian and Chinese parts of the Amur River basin point to the possible existence of at least two distinct populations of Amur sturgeon in the past.

  11. Contaminants in white sturgeon (Acipenser transmontanus) from the upper Fraser River, British Columbia, Canada

    SciTech Connect

    MacDonald, D.D.; Ikonomou, M.G.; Rantalaine, A.L.; Rogers, I.H.; Sutherland, D.; Oostdam, J. Van

    1997-03-01

    Four white sturgeon were collected from the upper Fraser River near Prince George, British Columbia, Canada, in the fall of 199a and 1992. Two additional fish were taken from the Fraser River near Williams Lake, some 250 km downstream of Prince George. Samples of white muscle, red muscle, liver, and roe were analyzed for metals, polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), non-ortho and mono-ortho polychlorinated biphenyls (PCBs), and chlorophenols to determine whether the tissues of this species were acceptable for human consumption. The concentrations of mercury in the white muscle and liver of several fish from the upper Fraser River exceeded the provincial tissue residue criteria for people who consumed low quantities of fish. The concentrations of PCDDs, PCDFs, and coplanar PCBs (expressed as 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents) in red muscle and liver of these fish exceeded the Health Canada working guidelines for the protection of human health. By comparison, white sturgeon collected in the lower Fraser River had much lower concentrations of metals and organic contaminants. The differences in contaminant burdens in fish from the two widely separated reaches of the river reflect their proximity to or distance from known contaminant sources.

  12. Assessment of lake sturgeon (Acipenser fulvescens) spawning efforts in the lower St. Clair River, Michigan

    USGS Publications Warehouse

    Nichols, S. Jerrine; Kennedy, Gregory; Crawford, Eric; Allen, Jeffrey; French, John; Black, Glen; Blouin, Marc; Hickey, James P.; Chernyak, Sergei; Haas, Robert; Thomas, Michael

    2003-01-01

    One of the most threatened remaining populations of lake sturgeon in the Great Lakes is found in the connecting channels between Lake Huron and Lake Erie. Only two spawning grounds are presently known to be active in this region, and both are in the St. Clair River. The spawning reef in the St. Clair River delta has been recently colonized by round gobies (Neogobius melanostomus) in densities up to 25/m2, raising concerns regarding predation on the benthic-oriented eggs and larvae of the sturgeon. Investigations in 1998–1999 showed that while round goby predation does occur, a number of other factors may be equally affecting sturgeon spawning success, including few spawning adults (< 60), suspected poaching pressure, low retention rate of eggs on the reef, low hatch rate (~0.5%), the presence of organic contaminants, and predation from native and exotic invertebrates and fish. Overall, we estimate that less than 1% of the eggs deposited during a spawning run survive to hatch. We were able to increase the egg hatch rate to 16% by placing eggs in predator-exclusion chambers on the reef. The fate of the larvae is uncertain. Two weeks after hatching, no larvae were found on the reef. We were unable to find them anywhere else in the river, nor was predation on larvae noted in either year. There were factors other than predation affecting larval survival in 1999. There was a higher silt load on the reef than in 1998 and large numbers of dead larvae were found. Recruitment success from this site could be improved by utilizing techniques to increase the number of eggs on the reef, such as reducing the illegal take of adult fish and by placing eggs in predator-exclusion chambers to increase hatch rate.

  13. Columbia River White Sturgeon (Acipenser Transmontanus) Enhancement, May 1-December 31, 1983 Final Report.

    SciTech Connect

    Brannon, E.L.

    1984-12-01

    Studies were undertaken to examine and define the early life history characteristics of Columbia River white sturgeon as a working base from which enhancement measures could be developed. Adult sturgeon were captured and held for spawning at Covert's Landing, the site of the hatchery facilities below Bonneville Dam. Pituitary hormones stimulated ovulation; ripe females were live spawned surgically and the eggs incubated in hatching jars. Larvae were either reared at the hatchery site after incubation to advanced fingerling stages or transferred to the University laboratory for more detailed study. Displacement downstream occurs as a means of distribution and can last several days before a strong substrate preference is manifested. Once bottom contact is sought by the larvae, displacement is abated, and a general preference for sandy surface appears to predominate. Since potentially extensive displacement downstream could result in the distribution of larvae in saltwater, the tolerance of young sturgeon to saltwater was examined. The responsiveness of young sturgeon to artificial feed was positive. With these results, the original concern for identifying an adequate diet and food source that would be readily accepted by fry was greatly attenuated. The readiness of young fry to initiate feeding on the artificial diet made further study on feeding stimulants unnecessary. Examination of the feeding response suggested that as long as the diet used in the present study was initiated at the proper time and with adequate frequency, the fry would feed quite well and survive. 6 refs., 10 figs., 5 tabs.

  14. Sex assignment of lake sturgeon (Acipenser fluvescens) based on plasma sex hormone and vitellogenin levels

    USGS Publications Warehouse

    Craig, J.M.; Papoulias, D.M.; Thomas, M.V.; Annis, M.L.; Boase, J.

    2009-01-01

    This study focused on identifying the sex of lake sturgeon by measuring the sex hormones estradiol and testosterone, and the phosphoprotein vitellogenin (Vtg) in blood plasma by radioimmunoassay and enzyme-linked immunosorbent assay, respectively, and evaluating these techniques as tools in lake sturgeon population management. Surveys of the St Clair River (SCR) lake sturgeon population have characterized it as rebounding by having steady or increasing recruitment since 1997. However, researchers have not been able to effectively determine the sex for most of the sturgeon they capture because few fish caught during surveys are releasing gametes. A total of 115 fish were sampled from May through June in 2004 and 2005 from the SCR, Michigan, USA. Of these, only four females and eight males were verified (i.e. they were releasing gametes at time of capture), resulting in very few fish with which to validate blood hormone and Vtg biomarkers of sex. Fifty-six percent of the fish were assigned a sex designation based on biomarker criteria. Correspondence between actual gonadal sex and biomarker-directed classification was good for the small subset of fish for which gonadal sex was definitively determined. Moreover, application of the steroid values in a predictive sex assignment model developed for white sturgeon misclassified only the same two fish that were misclassified with the steroid and Vtg biomarkers. The experimental results suggest a sex ratio of 1 : 2.7 (F:M), however more conclusive methods are needed to confirm this ratio because so few fish were available for sex validation. Of the 43 males, 14 were within the legal slot limit, 11 were smaller than 1067 mm total length (TL), and 18 were larger than 1270 mm TL. All 15 females were larger than 1270 mm TL, and thus protected by the slot limit criteria. Considering that lake sturgeon are threatened in Michigan, an advantage to using blood plasma assays was that fish were not harmed, and sample collection was quick, simple, and inexpensive. However, because a sufficiently large number of fish could not be validated for gonadal sex due to handling restrictions given the fish's protected status, assignment of sex is not based on a robust multi-variate model. An immediate alternative may be to use other non-invasive field methods (e.g. ultrasound, fiber-optic endoscope) to provide a more timely classification while establishing well-validated plasma hormone and Vtg-based predictive models for sex assignment of lake sturgeon. ?? 2009 Blackwell Verlag, Berlin.

  15. Determination of cortisol in lake sturgeon (Acipenser fulvescens) eggs by liquid chromatography tandem mass spectrometry.

    PubMed

    Bussy, Ugo; Wassink, Lydia; Scribner, Kim T; Li, Weiming

    2017-01-01

    Quantifying cortisol concentrations in fish eggs is important to understand the effects of environmental conditions on maternal physiological condition and on egg provisioning and quality. Data are particularly relevant to studies of the ecology of threatened species such as lake sturgeon (Aciperser fulvescens) as well as assessments of larval physical and behavioral phenotypes, fish health and caviar quality in sturgeon aquaculture. This study focuses on development of bioanalytical methods for high sensitivity and robust determination of cortisol in sturgeon eggs. Sample preparation was optimized after investigating protein precipitation and liquid-liquid extraction techniques. Ethyl acetate was found to be the most efficient solvent (recovery parameter) and also provided the best sample clean up (matrix effect parameter). The method was determined to be linear for cortisol concentrations between 0.025 and 100ng/mL. The limits of detection and quantification were 0.025 and 0.1ng/mL respectively. Intra- and inter-day performances of the method were validated at three concentrations (0.25; 10 and 100ng/mL). The method was applied to field-collected samples for the determination of endogenous cortisol in lake sturgeon eggs. Cortisol was detected in all egg samples and statistical analysis showed significant differences between fertilized and non-fertilized eggs.

  16. Heteroplasmy in the mtDNA control region of sturgeon (Acipenser, Huso and Scaphirhynchus).

    PubMed Central

    Ludwig, A; May, B; Debus, L; Jenneckens, I

    2000-01-01

    Data from 1238 fishes from 19 sturgeon species and 1 paddlefish were used to analyze heteroplasmy in sturgeon. Lengths of central repeat units ranged from 74 to 83 bp among sturgeon species. No repeat sequence was found in the paddlefish, Polyodon spathula. A general feature of the repeat units was the presence of termination associated sequence (TAS) motifs. About 50% of 138 interspecific mutations observed among the D-loop sequences are located 10 bp down- and upstream from these TAS motifs. Interestingly, most homoplasmic species showed deletions upstream to the TAS motifs, whereas deletions downstream to the TAS motifs observed in two species do not seem to preclude heteroplasmy. Calculations of secondary structures and thermal stabilities of repeat units showed DeltaG values for all heteroplasmic species to be <-8 and for most homoplasmic species DeltaG value to be >-8. Most heteroplasmic fishes had two and/or three repeat units. No homoplasmic sturgeon with >2 repeat units were observed. Molecular phylogeny based on the entire cytochrome b showed that heteroplasmy probably resulted from a single evolutionary event. Our data demonstrate that heteroplasmy is present in most sturgeon species and suggest that the thermal stability of the secondary structure of the repeat unit in combination with mutations downstream of the TAS sequences influences heteroplasmy. PMID:11102385

  17. Confirmation of ovarian homogeneity in post-vitellogenic cultured white sturgeon, Acipenser transmontanus.

    PubMed

    Talbott, Mariah J; Servid, Sarah A; Cavinato, Anna G; Van Eenennaam, Joel P; Doroshov, Serge I; Struffenegger, Peter; Webb, Molly A H

    2014-02-01

    Assessing stage of oocyte maturity in female sturgeon by calculating oocyte polarization index (PI) is a necessary tool for both conservation propagation managers and caviar producers to know when to hormonally induce spawning. We tested the assumption that sampling ovarian follicles from one section of one ovary is sufficient for calculating an oocyte PI representative of oocyte maturity for an individual animal. Short-wavelength near-infrared spectroscopy (SW-NIR) scans were performed on three positions per ovary for five fish prior to caviar harvest. Samples of ovarian follicles were subsequently taken from the exact location of the SW-NIR scans for calculation of oocyte PI and follicle diameter. Oocyte PI was statistically different though not biologically relevant within an ovary and between ovaries in four of five fish. Follicle diameter was statistically different but not biologically relevant within an ovary in three of five fish. There were no differences in follicle diameter between ovaries. No statistical differences were observed between SW-NIR spectra collected at different locations within an ovary or between ovaries. These results emphasize the importance of utilizing both oocyte PI measurement and progesterone-induced oocyte maturation assays while deciding when to hormonally induce spawning in sturgeon females.

  18. Effects of feed restriction on salinity tolerance in white sturgeon (Acipenser transmontanus).

    PubMed

    Lee, Seunghyung; Fadel, James G; Haller, Liran Y; Verhille, Christine E; Fangue, Nann A; Hung, Silas S O

    2015-10-01

    A multistressor study was conducted to investigate interactive effects of nutritional status and salinity on osmoregulation of juvenile white sturgeon. Our hypothesis was that lower nutritional status would decrease the salinity tolerance of juvenile white sturgeon. A four-week feed restriction (12.5%, 25%, 50%, 100% of optimum feeding rate: OFR defined as the rate (% body weight per day) at which growth is maximal) trial was performed, and relevant indices of nutritional status were measured. Following the trial, sturgeon were acutely exposed to various salinities (0, 8, 16, 24 ppt) for 120 h, and relevant osmoregulatory measurements were made at 12, 72, and 120 h post-salinity exposures. The feed-restriction trial resulted in a graded nutritional response with the most feed-restricted group (12.5% OFR) showing the lowest nutritional status. The salinity exposure trial showed clear evidence that lower nutritional status decreased the salinity tolerance of juvenile white sturgeon. Increasing salinities resulted in significant alterations in osmoregulatory indices of all feeding groups; however, a significantly slower acclimatory response to 24 ppt was detected in the most feed-restricted group compared to the non-feed-restricted group (100% OFR). Furthermore, evaluation of the effect of nutritional status on the relationship between osmoregulatory measurements and body size showed that there was a significant negative relationship between osmoregulatory performance and body size within the most feed-restricted group. This suggests that there is a certain body size range (200-300 g based on our finding) where juvenile white sturgeon can maximize osmoregulatory capacity at a salinity of 24 ppt.

  19. Toxicokinetics and biotransformation of p-nitrophenol in white sturgeon (Acipenser transmontanus).

    PubMed

    TenBrook, P L; Kendall, S M; Tjeerdema, R S

    2006-07-01

    White sturgeon (Acipencer transmontanus) were exposed to 7.2 microM (1.0 ppm) 14C-labeled p-nitrophenol (PNP) in brackish water for 24 h and then allowed to depurate in clean brackish water for another 24h. Absorption, conditional uptake clearance, and conditional elimination rate constants were 0.08+/-0.04 h(-1), 8.1+/-3.6 mL g(-1) h(-1), and 0.46+/-0.21 h(-1), respectively. A whole-organism total concentration factor of 18.7+/-2.6 was determined from equilibrium tissue and water concentrations. Sturgeon depurated 89.4% of absorbed PNP within 24h, of which 53.0+/-8.3% was unmetabolized parent compound, 9.6+/-3.6% was p-nitrophenyl-beta-d-glucuronide, and 39.1+/-8.3% was p-nitrophenylsulfate.

  20. Olfactory projections in the white sturgeon, Acipenser transmontanus: an experimental study.

    PubMed

    Northcutt, R Glenn

    2011-07-01

    Telencephalic evolution in ray-finned fishes shows increasing complexity from polypteriform fishes through sturgeons to teleosts. Telencephalic organization in sturgeons is thus critical to our understanding of ray-finned fish evolution, but it is poorly understood, particularly as regards the roof or pallium. Two major hypotheses exist regarding the medial part of area dorsalis (Dm): that Dm is extended; and that Dm is restricted. The extent and topography of secondary olfactory projections to the pallium are critical in evaluating these hypotheses, but there is little agreement regarding these projections. Olfactory projections in the white sturgeon were therefore examined by using the carbocyanine probe DiI, biocytin, and biotinylated dextrin amine (BDA). Both DiI and BDA revealed primary olfactory projections to the olfactory bulb and primary extrabulbar projections widely in the telencephalon and to more restricted regions of the diencephalon. Myelinated secondary olfactory fibers caused DiI to be less effective in labeling secondary olfactory projections, which terminate in all subpallial nuclei and in the pallium: sparsely in the medial pallial division (Dm); heavily in the posterior pallial division (Dp); and more lightly in the lateral pallial division (Dl). In the diencephalon, substantial secondary olfactory projections were seen to the habenular nuclei, the rostral pole of the inferior lobe, and several nuclei of the posterior tubercle. All secondary olfactory projections were bilateral but heavier ipsilaterally. Bulbopetal neurons were located in both pallial and subpallial centers and were more numerous ipsilaterally. These results corroborate an earlier experimental study on the shovelnose sturgeon and indicate a restricted Dm in sturgeons.

  1. Immunohistochemical organization of the forebrain in the white sturgeon, Acipenser transmontanus.

    PubMed

    Piñuela, Carmen; Northcutt, R Glenn

    2007-01-01

    The distribution of substance P (SP), leucine-enkephalin (LENK), serotonin (5HT), dopamine (DA), and tyrosine hydroxylase (TH) was examined in the forebrain of the white sturgeon in order to evaluate several anatomical hypotheses based on cytoarchitectonics, and to gain a better understanding of the evolution of the forebrain in ray-finned fishes. The subpallium of the telencephalon has the highest concentration of the neuropeptides SP and LENK, allowing the pallial-subpallial border to be easily distinguished. The distribution of dopamine is similar to that of serotonin in the subpallium, fibers positive for these transmitters are particularly dense in the dorsal and ventral divisions of the subpallium. In addition, a small population of DA- and 5HT-positive cell bodies--which appear to be unique to sturgeons--was identified at the level of the anterior commissure. The internal granular layer of the olfactory bulbs had large numbers of TH-positive cell bodies and fibers, as did the rostral subpallium. The occurrence of cell bodies positive for LENK in the dorsal nucleus of the rostral subpallium supports the hypothesis that this nucleus is homologous to the striatum in other vertebrates. This is further reinforced by the apparent origin of an ascending dopaminergic pathway from cells in the posterior tubercle that are likely homologous to the ventral tegmental area/substantia nigra in land vertebrates. Finally, the differential distribution of SP and TH in the pallium supports the hypothesis that the pallium, or area dorsalis, can be divided medially into a rostral division (Dm), a caudal division (Dp) that is the main pallial target of secondary olfactory projections, and a narrow lateral division (Dd+Dl) immediately adjacent to the attachment of the tela choroidea along the entire rostrocaudal length of the telencephalic hemisphere.

  2. 78 FR 58507 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List 10 Sturgeon...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-24

    ... construction, and water pollution. The petition is available at http://www.nmfs.noaa.gov/pr/pdfs/petitions... sturgeon (Acipenser baerii). Endangered Decreasing China; Kazakhstan; Mongolia; Russia. Yangtze sturgeon (Acipenser Critically Endangered.. Decreasing China. dabryanus). Russian sturgeon (Acipenser...

  3. Reliability of fish size estimates obtained from multibeam imaging sonar

    USGS Publications Warehouse

    Hightower, Joseph E.; Magowan, Kevin J.; Brown, Lori M.; Fox, Dewayne A.

    2013-01-01

    Multibeam imaging sonars have considerable potential for use in fisheries surveys because the video-like images are easy to interpret, and they contain information about fish size, shape, and swimming behavior, as well as characteristics of occupied habitats. We examined images obtained using a dual-frequency identification sonar (DIDSON) multibeam sonar for Atlantic sturgeon Acipenser oxyrinchus oxyrinchus, striped bass Morone saxatilis, white perch M. americana, and channel catfish Ictalurus punctatus of known size (20–141 cm) to determine the reliability of length estimates. For ranges up to 11 m, percent measurement error (sonar estimate – total length)/total length × 100 varied by species but was not related to the fish's range or aspect angle (orientation relative to the sonar beam). Least-square mean percent error was significantly different from 0.0 for Atlantic sturgeon (x̄  =  −8.34, SE  =  2.39) and white perch (x̄  = 14.48, SE  =  3.99) but not striped bass (x̄  =  3.71, SE  =  2.58) or channel catfish (x̄  = 3.97, SE  =  5.16). Underestimating lengths of Atlantic sturgeon may be due to difficulty in detecting the snout or the longer dorsal lobe of the heterocercal tail. White perch was the smallest species tested, and it had the largest percent measurement errors (both positive and negative) and the lowest percentage of images classified as good or acceptable. Automated length estimates for the four species using Echoview software varied with position in the view-field. Estimates tended to be low at more extreme azimuthal angles (fish's angle off-axis within the view-field), but mean and maximum estimates were highly correlated with total length. Software estimates also were biased by fish images partially outside the view-field and when acoustic crosstalk occurred (when a fish perpendicular to the sonar and at relatively close range is detected in the side lobes of adjacent beams). These sources of

  4. Histopathological study of gill, kidney and liver of Persian Sturgeon (Acipenser persicus Borodin, 1897) and Stellate (Acipenser stellatus Pallas, 1811) exposed to sublethal concentration of un-ionised ammonia UAN.

    PubMed

    Banihashemi, Elham Sadat; Khara, Hossein; Pajand, Zabiyollah; Rahnandeh, Mohammad

    2016-12-01

    This study was carried out to investigate the histopathological changes of gill, kidney and liver of Persian Sturgeon and Stellate in response to various sublethal concentration of ammonia. The sublethal doses were determined after a lethal pre-test and then the experiment was done in six treatments with three replicates for both species. In Persian sturgeon, the treatments were including 5, 7, 9.7, 13.2, 18 and 25 mg/l ammonia. In stellate, the concentrations of 5, 6.23, 7.76, 9.66, 12.04 and 15 mg/l ammonia were considered as treatments. Also, one group without ammonia was considered as control for each experiment. The histopathological investigations were done after 96 h exposure. According to our observations, a range of histopathological alternations were found in gill, liver and kidney of both examined fish. The alternations of gill tissue were lamellar necrosis, hyperplasia, lamellar adhesion, haemorrhage, swelling of gill lamellae. Severity of these alternations was dose-dependent and was significantly higher in Persian sturgeon than in stellate. The degree of histopathological alternations of liver did not show a regular pattern between treatments in both species. These alternations were hyperemia, bile record, cell necrosis, cell atrophy, fatty degeneration and cloudy swelling. The signs of kidney alternations intensified with increasing of ammonia concentration in both species. The signs such as hyperemia, vision tissue degeneration, cell necrosis, dilatation of Bowman's space. In conclusion, our results showed that ammonia in concentration of more than 5 mg/l have more adverse impacts on gill, liver and kidney tissues.

  5. 50 CFR 660.702 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (Tetrapturus audax) swordfish (Xiphias gladius) Sharks: common thresher shark (Alopias vulpinus) shortfin mako or bonito shark (Isurus oxyrinchus) blue shark (Prionace glauca) Tunas: north Pacific...

  6. 50 CFR 660.702 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (Tetrapturus audax) swordfish (Xiphias gladius) Sharks: common thresher shark (Alopias vulpinus) shortfin mako or bonito shark (Isurus oxyrinchus) blue shark (Prionace glauca) Tunas: north Pacific...

  7. 15 CFR 922.71 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... mackerel (Scomber japonicus), salmon (Oncorhynchus spp.), Pacific sardine (Sardinops sagax), blue shark (Prionace glauca), salmon shark (Lamna ditropis), shortfin mako shark (Isurus oxyrinchus), thresher...

  8. Effects of thermal regime on ovarian maturation and plasma sex steroids in farmed white sturgeon, Acipenser transmontanus

    USGS Publications Warehouse

    Webb, M.A.H.; Van Eenennaam, J. P.; Feist, G.W.; Linares-Casenave, J.; Fitzpatrick, M.S.; Schreck, C.B.; Doroshov, S.I.

    2001-01-01

    Recently, commercial aquaculture farms in Northern California have exposed gravid, cultured white sturgeon females to cold water (12 ?? 1??C) throughout the late phase of vitellogenesis and ovarian follicle maturation resulting in improved ovulation rates and egg quality. However, the optimum timing for transfer of broodfish to the cold water and the capacity of transferred broodfish to maintain reproductive competence over an extended time in cold water had not been evaluated. Gravid white sturgeon females that have been raised at water temperatures of 16-20??C were transported to either cold water (12 ?? 1??C; Group 1) in November 1997 or maintained in ambient water temperatures (10-19??C; Group 2) until early spring. In March 1998, half of the fish in Group 2 had regressed ovaries, but the remaining females had intact ovarian follicles and were transported to the cold water. Ovarian follicles and blood were collected from females until they reached the stage of spawning readiness (determined by germinal vesicle position and an oocyte maturation assay) or underwent ovarian regression. Exposure of gravid sturgeon females to ambient water temperatures (14.5 ?? 2.3??C, mean ?? S.D.) from October to March led to a decrease in plasma sex steroids and a high incidence of ovarian regression in fish with a more advanced stage of oocyte development. Transfer of females with intact ovarian follicles to cold water (12 ?? 1??C) in the fall or early spring resulted in normal ovarian development in the majority of females. Holding females in cold water does not seem to override their endogenous reproductive rhythms but extends their capacity to maintain oocyte maturational competence over a longer period of time. A temperature-sensitive phase in ovarian development may occur during the transition from vitellogenic growth to oocyte maturation, and the degree and timing of sensitivity to environmental temperature are dependent on the female's endogenous reproductive rhythm. ?? 2001 Elsevier Science B.V. All Rights reserved.

  9. High-throughput sequencing of microRNA transcriptome and expression assay in the sturgeon, Acipenser schrenckii.

    PubMed

    Yuan, Lihong; Zhang, Xiujuan; Li, Linmiao; Jiang, Haiying; Chen, Jinping

    2014-01-01

    Sturgeons are considered as living fossils and have very high evolutionary, economical and conservation values. The multiploidy of sturgeon that has been caused by chromosome duplication may lead to the emergence of new microRNAs (miRNAs) involved in the ploidy and physiological processes. In the present study, we performed the first sturgeon miRNAs analysis by RNA-seq high-throughput sequencing combined with expression assay of microarray and real-time PCR, and aimed to discover the sturgeon-specific miRNAs, confirm the expressed pattern of miRNAs and illustrate the potential role of miRNAs-targets on sturgeon biological processes. A total of 103 miRNAs were identified, including 58 miRNAs with strongly detected signals (signal >500 and P≤0.01), which were detected by microarray. Real-time PCR assay supported the expression pattern obtained by microarray. Moreover, co-expression of 21 miRNAs in all five tissues and tissue-specific expression of 16 miRNAs implied the crucial and particular function of them in sturgeon physiological processes. Target gene prediction, especially the enriched functional gene groups (369 GO terms) and pathways (37 KEGG) regulated by 58 miRNAs (P<0.05), illustrated the interaction of miRNAs and putative mRNAs, and also the potential mechanism involved in these biological processes. Our new findings of sturgeon miRNAs expand the public database of transcriptome information for this species, contribute to our understanding of sturgeon biology, and also provide invaluable data that may be applied in sturgeon breeding.

  10. Conservation, sex-biased expression and functional annotation of microRNAs in the gonad of Amur sturgeon (Acipenser schrenckii).

    PubMed

    Zhang, Xiujuan; Yuan, Lihong; Li, Linmiao; Jiang, Haiying; Chen, Jinping

    2016-06-01

    MicroRNAs (miRNAs) are involved in post-transcriptional gene regulation and have crucial roles in regulating the expression of gametogenesis-related genes in animals. However, the mechanism of sex determination and differentiation in the sturgeon has remained unclear. Identifying miRNAs and characterizing sex-biased miRNA expression is therefore critical for understanding the role of miRNAs during sexual differentiation in sturgeon. In this study, five different tissues from sturgeon before sex differentiation and the gonads were used for miRNA expression profiling. We screened 1037 miRNAs in miRBase 20.0 and an additional 103 sturgeon miRNAs using microarray and real-time PCR. We found that the sequences of 477 miRNAs out of a total of 1140 miRNAs were highly conserved (100%) among different fish species. From a total of 663 non-redundant miRNA probes, 481 miRNAs were detected in the gonads of both sexes. Of the 148 miRNAs that were identified to have sex-biased expression patterns between the testis and the ovary (P<0.01), 21 miRNAs (14.19%) were relatively highly expressed in the testis or the ovary with fold-changes >2. The microarray expression patterns of 13 randomly selected sex-biased miRNAs were validated using real-time PCR. Target gene prediction revealed a significant enrichment of functional groups (88 GO terms) and 18 KEGG pathways (P<0.05) and suggested that there are interactions between sex-biased miRNAs and 25 putative gametogenesis-related targets. Therefore, our miRNA expression analysis in juvenile A. schrenckii establishes a foundation for understanding and further investigating the role of miRNAs in sturgeon sex differentiation.

  11. Histopathological and bacterial study of Persian sturgeon fry, Acipenser persicus (Borodin, 1897) exposed to copper sulfate and potassium permanganate.

    PubMed

    Moshtaghi, Batol; Khara, Hossein; Pazhan, Zabiyollah; Shenavar, Alireza

    2016-09-01

    Persian sturgeon frys were exposed to different concentrations of copper sulfate and potassium permanganate in order to the evaluation of their impacts on bacterial load of skin, gill and surrounding water and also the histopathological alternations of gill tissue. For this purpose, the sublethal doses were determined after a pre-test and then the experiment was done in 4 (for copper sulfate: 0.07, 0.14, 026 and 0.5 mg/l) and 5 (for potassium permanganate: 0.07, 0.14, 026, 0.5 and 1 mg/l) treatments with three replicates inside the glass aquaria. Also, one group without disinfecting drug was considered as control for each experiment. The microbial and histopathological investigations were done after 96 h exposure. According to our results, a range of histopathological alternations were observed in gills tissue including mucus coagulation and secretion, hyperplasia, lamellar necrosis, hyperplasia, lamellar adhesion, haemorrhage, thickening of secondary lamellae, hypertrophy of supporter cartilage, clubbing of gill lamellae and sliming of primary lamellae. The severity of these alternations increased with increasing of the doses of the copper sulfate and potassium permanganate. The bacterial load (CFU/g) of gill, skin and surrounding water was lower in 0.07 mg/l copper sulfate treatment and 1 mg/l potassium permanganate treatment (P < 0.05) than in other treatments. In conclusion, our results showed that the certain doses of the copper sulfate and potassium permanganate have disinfecting effects on bacterial load of gill, skin and surrounding water, although this is along with some histopathological alternations. Also, it seems that the copper sulfate has higher disinfecting power than potassium permanganate.

  12. Known lake sturgeon (Acipenser fulvescens) spawning habitat in the channel between lakes Huron and Erie in the Laurentian Great Lakes

    USGS Publications Warehouse

    Manny, B.A.; Kennedy, G.W.

    2002-01-01

    Bottom substrates and overlying water at three sites where lake sturgeon were reported by others to spawn in the 160-km channel between lakes Huron and Erie were surveyed by boat just before or after the exact time of spawning in 2001 to determine the kinds of substrates present and differences in water quality at the sites. Substrates, examined and photographed using a high-resolution, underwater, video camera, were beds of either rounded cobble (10-40 cm in diameter) and coarse gravel (2-8 cm in diameter) of glacial origin or coal cinders (0.5-12 cm in diameter) of human origin, >1/4 ha in area and >0.3 m in thickness. Water quality, defined as percent of surface light reaching the bottom (range: 0.05-8.7%), Secchi disc depth (range: 2.5-6.5 m), and water current velocity (range: 0.35-0.98 m s-1), differed more than 3-fold between the three sites. Although water depth at these sites (range: 9-12 m) was greater than in many rivers elsewhere used by lake sturgeon, the water current velocities at these sites were in the range in which lake sturgeon were reported to deposit eggs in two small Canadian rivers (0.1-1.1 m s-1).

  13. Identification of the origin and localization of chorion (egg envelope) proteins in an ancient fish, the white sturgeon, Acipenser transmontanus.

    PubMed

    Murata, Kenji; Conte, Fred S; McInnis, Elizabeth; Fong, Tak Hou; Cherr, Gary N

    2014-06-01

    In many modern teleost fish, chorion (egg envelope) glycoproteins are synthesized in the liver of females, and the expression of those genes is controlled by endogenous estrogen released from the ovary during maturation. However, among the classical teleosts, such as salmonid, carp, and zebrafish, the chorion glycoproteins are synthesized in the oocyte, as in higher vertebrates. Sturgeon, which are members of the subclass Chondrostei, represent an ancient lineage of ray-finned fishes that differ from other teleosts in that their sperm possess acrosomes, their eggs have numerous micropyles, and early embryo development is similar to that of amphibians. In order to understand the molecular mechanisms of chorion formation and the phylogenetic relationship between sturgeon and other teleosts, we used specific antibodies directed against the primary components of sturgeon chorion glycoproteins, using immunoblotting and immunocytochemistry approaches. The origin of each chorion glycoprotein was determined through analyses of both liver and ovary, and their localization during ovarian development was investigated. Our data indicate that the origin of the major chorion glycoproteins of sturgeon, ChG1, ChG2, and ChG4, derive not only from the oocyte itself but also from follicle cells in the ovary, as well as from hepatocytes. In the follicle cell layer, granulosa cells were found to be the primary source of ChGs during oogenesis in white sturgeon. The unique origins of chorion glycoproteins in sturgeon suggest that sturgeons are an intermediate form in the evolution of the teleost lineage.

  14. Effects of chronic exposure to dietary selenomethionine on the physiological stress response in juvenile white sturgeon (Acipenser transmontanus).

    PubMed

    Patterson, Sarah; Zee, Jenna; Wiseman, Steve; Hecker, Markus

    2017-02-03

    Selenium (Se) is an essential micronutrient, but at low concentrations can be toxic to aquatic organisms. Selenomethionine (SeMeth) is the primary dietary form of Se aquatic organisms are exposed to and is an environmental concern because it persists and bioaccumulates. White sturgeon (WS) might be particularly susceptible to bioaccumulative toxicants, such as SeMeth, due to their longevity and benthic lifestyle. Se exposure is known to have adverse effects on the physiological stress response in teleosts, but these effects are unknown in WS. Therefore, the goal of this study was to determine effects of dietary SeMeth on the ability of WS to mount a stress response. Juvenile WS were administered food spiked with 1.4, 5.6, 22.4 and 104.4μg Se/g dry mass (dm) for 72days. Lower doses were chosen to represent environmentally relevant concentrations, while the high dose represented a worst case scenario exposure. On day 72, fish were subjected to a 2min handling stressor, and they were sampled at 0, 2 and 24h post-stressor. Cortisol, glucose and lactate concentrations were quantified in blood plasma and glycogen concentrations were quantified in muscle and liver. Transcript abundance of genes involved in corticosteroidogenesis and energy metabolism were determined using qPCR. Under basal conditions, WS fed 104.4μg Se/g dm had significantly greater concentrations of plasma cortisol and lactate, and significantly lower concentrations of plasma glucose and liver glycogen, compared to controls. Corticosteroid 11-beta dehydrogenase 2 (hsd11b2) abundance was lower in WS fed 22.4 and 104.4μg Se/g dm, indicating less conversion of cortisol to cortisone. Abundance of the glucocorticoid receptor (gcr) was significantly lower in high dose WS, suggesting lower tissue sensitivity to glucocorticoids. The increasing trend in phosphoenolpyruvate carboxykinase (pepck) abundance, with increasing SeMeth exposure, was consistent with greater cortisol and glucose concentrations in high dose WS. Exposure to an acute handling stressor elicited a typical cortisol response, but the magnitude of the response appeared to be significantly lower than those typically observed in teleosts. SeMeth also did not appear to modulate the cortisol response to a secondary stressor. However, WS exposed to 22.4μg Se/g dm and sampled 2h post-stressor, had significantly higher concentrations of muscle glycogen compared to controls, indicating effects on their ability to utilize muscle glycogen for energy. Overall, the results indicate that chronic exposure to dietary SeMeth concentrations >22.4μg/g can affect cortisol dynamics and mobilization of energy substrates in juvenile WS.

  15. Effects of dietary methylmercury on growth performance and tissue burden in juvenile green (Acipenser medirostris) and white sturgeon (A. transmontanus).

    PubMed

    Lee, Jang-Won; De Riu, Nicola; Lee, Seunghyung; Bai, Sungchul C; Moniello, Giuseppe; Hung, Silas S O

    2011-10-01

    Triplicate groups of juvenile green and white sturgeon (30 ± 2 g) were exposed to one of the four nominal concentrations of dietary methylmercury (MeHg, 0 (control), 25, 50, and 100mg MeHg/kg diet) for 8 weeks to determine and compare the effects on growth performance and mercury (Hg) tissue burden in the two sturgeon species. Mortality, growth performance as measured by percent body weight increase per day, hepatosomatic index, proximate composition of whole body, and Hg burden in the whole body, gill, heart, liver, kidney, and white muscle were determined to assess the adverse growth effects and bioaccumulation of dietary MeHg in sturgeon. Significantly higher mortality and lower growth rate (p<0.05) were noted in green and white sturgeon fed the MeHg diets compared to the controls. Green sturgeon fed the MeHg diets exhibited earlier and more severe adverse effects compared to white sturgeon. Mercury accumulated in all tissues in a dose-dependent manner regardless of species, and the highest Hg concentrations were found in the kidneys of both species. Dietary MeHg had no significant effect (p>0.05) on the whole body proximate compositions of either sturgeon species. In conclusion, green sturgeon was more susceptible to dietary MeHg toxicity than white sturgeon in our 8-week growth experiment based on the higher mortality and lower growth rate and body energy contents.

  16. Selenium tissue burden compartmentalization in resident white sturgeon (Acipenser transmontanus) of the San Francisco Bay Delta estuary.

    PubMed

    Linares-Casenave, Javier; Linville, R; Van Eenennaam, J P; Muguet, J B; Doroshov, S I

    2015-01-01

    High selenium (Se) loads in the San Francisco Bay Delta are bioaccumulated and biomagnified in food webs and can impair the reproduction of resident oviparous animals such as white sturgeon. The objective of the present study was to determine the Se tissue burden in San Francisco Bay Delta-resident white sturgeon to assess Se bioaccumulation in different organs, including ovaries and liver where egg yolk precursor proteins are synthesized. The authors obtained 54 San Francisco Bay Delta-resident white sturgeon including 26 female and 28 male subadults with immature gonads, 8 females with vitellogenic eggs, and 13 males with maturing gonads. Length, weight, age, reproductive stage of development, and kidney, liver, gonad, and muscle Se concentrations were determined in all fish. Concentrations of Se in muscle, gonads, and liver significantly increased with fish size, whereas kidney Se was not correlated to body size and was at the highest level compared with other organs. There was no difference between the sexes (p > 0.05) in Se concentrations in kidney (12.83 ± 0.51 µg · g(-1) dry wt), liver (11.85 ± 1.04 µg · g(-1) dry wt), and muscle (7.09 ± 0.52 µg · g(-1) dry wt; mean ± standard error, n = 47); but Se concentration was higher in the ovary than in testis (p = 0.04). Females with vitellogenic eggs had higher Se concentrations in the ovaries (20.77 ± 4.11 µg · g(-1) dry wt vs 5.22 ± 2.50 µg · g(-1) dry wt), liver (21.84 ± 2.07 µg · g(-1) dry wt vs 8.03 ± 1.03 µg · g(-1) dry wt), and muscle (10.18 ± 1.93 µg · g(-1) dry wt vs 5.48 ± 0.64 µg · g(-1) dry wt) compared with less advanced, previtellogenic females (p < 0.05). The elevated Se concentrations in the ovaries and liver of vitellogenic San Francisco Bay Delta white sturgeon were comparable with levels previously shown to cause reproductive toxicity in dietary Se experiments with captive white sturgeon.

  17. Metabolic changes associated with acid-base regulation during hypercarbia in the CO2-tolerant chondrostean, white sturgeon (Acipenser transmontanus).

    PubMed

    Baker, Daniel W; Brauner, Colin J

    2012-01-01

    CO(2) tolerance in white sturgeon is associated with the ability to tightly regulate intracellular pH (pHi) despite a large reduction in extracellular pH (pHe) termed preferential pHi regulation. How this regulatory response affects whole animal metabolic rate is unknown. Accordingly, we characterized oxygen consumption rate ( [Formula: see text] ) and metabolically-relevant organismal and cellular responses in white sturgeon during exposure to hypercarbia. White sturgeon were able to protect intracellular pH (pHi) in liver and white muscle as early as 6h (the earliest time period investigated) following exposure to severe (sub-lethal) hypercarbia (45 and 90 mm Hg PCO(2)). Sturgeon exposed to 15 and 30 mm Hg PCO(2) exhibited pHe compensation and significant increases in [Formula: see text] (up to 80% greater than control values). In contrast, severe hypercarbia (≥45 mm Hg PCO(2)) elicited an uncompensated reduction in pHe (up to ~1.0 pH units) and red blood cells (as great as ~0.5 pH units), and was accompanied by 30 and 60% reductions in [Formula: see text] , respectively. While behavioral, respiratory and cellular responses to hypercarbia were observed, none corresponded well with the pattern or magnitude of changes in [Formula: see text] . The findings of this research provide empirical support for the hypothesis that preferential pHi regulation is not metabolically costly, and thus may have been a strategy strongly selected for in fishes encountering short-term hypercarbia.

  18. Using blood plasma for monitoring organochlorine contaminants in juvenile white sturgeon, Acipenser transmontanus, from the lower Columbia River.

    PubMed

    Gundersen, D T; Webb, M A H; Fink, A K; Kushner, L R; Feist, G W; Fitzpatrick, M S; Foster, E P; Schreck, C B

    2008-09-01

    Organochlorine (OC) pesticide concentrations in blood plasma samples from 88 juvenile white sturgeon collected from the lower Columbia River were measured and compared to plasma sex steroid and OC tissue levels previously measured in corresponding fish. Significant squared correlation coefficients between summation operator DDT concentrations in sturgeon plasma and gonads and livers were 0.37 and 0.32, respectively. Significant negative correlations between plasma testosterone concentration and plasma Sigma DDT concentration in male fish (r(2)=0.26), plasma 17beta estradiol concentration and plasma Sigma DDT concentration in female fish (r(2)=0.38) and condition factor and plasma Sigma DDT concentration in all fish were found (r(2)=0.17). These results suggest that blood plasma may be a suitable nondestructive method for monitoring adult sturgeon population for persistent OC contaminants.

  19. Exceptional CO₂ tolerance in white sturgeon (Acipenser transmontanus) is associated with protection of maximum cardiac performance during hypercapnia in situ.

    PubMed

    Baker, Daniel W; Hanson, Linda M; Farrell, Anthony P; Brauner, Colin J

    2011-01-01

    White sturgeon rank among the most CO₂-tolerant fish species examined to date. We investigated whether this exceptional CO₂ tolerance extended to the heart, an organ generally viewed as acidosis intolerant. Maximum cardiac output (Q(max)) and maximum cardiac power output (PO(max)) were assessed using a working, perfused, in situ heart preparation. Exposure to a Pco₂ of 3 kPa for 20 min had no significant effect on maximum cardiac performance, while exposure to 6-kPa Pco₂ reduced heart rate, Q(max), PO(max), and rate of ventricular force generation (F(O)) by 23%, 28%, 26%, and 18%, respectively; however, full recovery was observed in all these parameters upon return to control conditions. These modest impairments during exposure to 6-kPa Pco₂ were associated with partially compensated intracellular ventricular acidosis. Maximum adrenergic stimulation (500 nmol L⁻¹ adrenaline) during 6-kPa Pco₂ protected maximum cardiac performance via increased inotropy (force of contraction) without affecting heart rate. Exposure to higher CO₂ levels associated with morbidity in vivo (i.e., 8-kPa Pco₂) induced arrhythmia and a reduction in stroke volume during power assessment. Clearly, white sturgeon hearts are able to increase cardiac performance during severe hypercapnia that is lethal to other fishes. Future work focusing on atypical aspects of sturgeon cardiac function, including the lack of chronotropic response to adrenergic stimulation during hypercapnia, is warranted.

  20. Effects of poly-β-hydroxybutyrate (PHB) on Siberian sturgeon (Acipenser baerii) fingerlings performance and its gastrointestinal tract microbial community.

    PubMed

    Najdegerami, Ebrahim H; Tran, Tiet Ngoc; Defoirdt, Tom; Marzorati, Massimo; Sorgeloos, Patrick; Boon, Nico; Bossier, Peter

    2012-01-01

    Poly-β-hydroxybutyrate (PHB) is a natural polymer that can be depolymerized into water-soluble short-chain fatty acid monomers. These monomers can act as microbial control agents. In this study, the effects of partially replacing the diet of Siberian sturgeon fingerlings with 2% and 5% PHB were investigated. Replacing 2% of the diet with PHB improved weight gain, specific growth rate (SGR) and survival in the sturgeon fingerlings during the 10-week experimental period. Community-level physiological profiling and PCR-denaturing gradient gel electrophoresis (PCR-DGGE) were used to analyze the microbial community diversity and community organization in the sturgeon gastrointestinal tract. DGGE analysis revealed that PHB affected the intestinal microbial species richness and diversity. The highest species richness was observed with 2% PHB. DNA sequencing of the dominant bands in 2% and 5% PHB treatments revealed that PHB stimulated bacteria belonging to the genera Bacillus and Ruminococcaceae. Principal component analysis, Lorenz curves and the Shannon index of Biolog Ecoplate data revealed that aerobic metabolic potential of the bacterial community was different in the PHB-treated fishes as compared with the control situation. Overall, our results indicate that PHB act as microbial control agents and replacement of 2% of Siberian sturgeon fingerling diet with PHB has beneficial effects.

  1. The transcription of l-gulono-gamma-lactone oxidase, a key enzyme for biosynthesis of ascorbate, during development of Persian sturgeon Acipenser persicus.

    PubMed

    Akbarzadeh, Arash; Farahmand, Hamid; Mahjoubi, Frouzandeh; Nematollahi, Mohammad Ali; Leskinen, Piia; Rytkönen, Kalle; Nikinmaa, Mikko

    2011-04-01

    l-Gulono-gamma-lactone oxidase (GULO) is a key enzyme for the biosynthesis of ascorbate, which is essential for several cellular functions. In the present study, mRNA expression of GULO gene was evaluated during the early development of Persian sturgeon. First, because there are no comparative studies that have established suitable quantitative real-time PCR reference genes in sturgeons for any physiological conditions, we evaluated six candidate reference genes (ACTB, RPL13, UBQ, RPL6, GAPDH and EF1A) during the early development of Persian sturgeon. The most stable mRNA expression was obtained with RPL6 and ACTB, whereas the least stable was RPL13. After normalization using RPL6, ACTB and RPL6/ACTB combination, the mRNA expression of GULO was highest at the embryonic stage (2days before hatching; P<0.05) and started to decline from hatching of larvae to the rest of the developmental time-points. This suggests that the vitamin C requirements are highest during early life stages, and it is likely that the changes in GULO mRNA expression are associated with changes in GULO enzyme activity.

  2. Inhibition of β-N-acetylglucosaminidase by acetamide affects sperm motility and fertilization success of rainbow trout (Oncorhynchus mykiss) and Siberian sturgeon (Acipenser baerii).

    PubMed

    Sarosiek, B; Glogowski, J; Cejko, B I; Kujawa, R; Szczepkowski, M; Kuźmiński, H; Dobosz, S; Kowalski, R K

    2014-03-15

    β-N-Acetylglucosaminidase (β-NAGase) is an enzyme found in the sperm acrosome of numerous animal species including fish. Fish spermatozoa differ in their morphology including acrosome or acrosomeless aquasperm in chondrostean (e.g., sturgeon) and teleostean (e.g., rainbow trout). It has been shown that β-NAGase exists with high activity in both eggs and sperm of these species. The present study shows the potency of β-NAGase in fertilization. In rainbow trout, increase in sperm motility parameters (VAP and MOT) were observed in the presence of acetamide, an inhibitor for β-NAGase. In contrast, sperm motility parameters (VCL, VSL, VAP, MOT, and PRG) were reduced on the Siberian sturgeon in the presence of acetamide. The inhibition of the activity of β-NAGase in rainbow trout spermatozoa was led to a reduction in the number of fertilized eggs from 79% to 40%, whereas in sturgeon no change was observed in fertilization. Moreover, inhibition of β-NAGase in both spermatozoa and eggs of trout and sturgeon resulted in significant decrease in fertilization rate from 79% to 1% in rainbow trout and from 84% to 12% in Siberian sturgeon. Our research proves that β-NAGase can play a significant role in the fertilization process in teleosteans.

  3. Characterization of type I and II procollagen α1 chain in Amur sturgeon (Acipenser schrenckii) and comparison of their gene expression.

    PubMed

    Zhang, Xi; Azuma, Noriko; Hagihara, Seishi; Adachi, Shinji; Ura, Kazuhiro; Takagi, Yasuaki

    2016-03-15

    To characterize type I and II collagen in the Amur sturgeon at the molecular level, mRNAs encoding the proα chain of both types of collagen were cloned and sequenced. Full sequences of both were obtained, and the molecular phylogeny based on the deduced amino acid sequence indicated that the correct sequences of the target genes were obtained. Analyses of primary structure of the proα chains revealed that type I and II collagen share the basic structure of the proα chain of fibril collagen, but have different characteristics, especially in residues related to thermal stability. In the triple helical domain, Gly-Pro-Pro sequence stabilizing the tripeptide unit was more frequent in type II than in type I, and Gly-Gly, which likely decline in thermal stability, was more frequent in type I than in type II. These results suggested that the denaturation temperature of type II would be remarkably higher than type I. The spatial pattern of gene expression was analyzed by quantitative real-time PCR, which showed that relatively ubiquitous type I gene and strongly skewed distribution of type II gene, which highly expressed only in vertebra, snout cartilage, and notochord. This pattern was similar to the distribution pattern of each collagen protein detected by previous biochemical analyses using Amur and Bester sturgeons. The present study is the first report of the cloning of the full-length cDNAs for both of type I and type II collagen in the Amur sturgeon, and is the first comparative analysis of type I and II collagens in a sturgeon species at the molecular level. The results provide basic and general information on collagens in sturgeons.

  4. Identification and sexually dimorphic expression of vasa isoforms in Dabry's sturgeon (Acipenser dabryanus), and functional analysis of vasa 3'-untranslated region.

    PubMed

    Ye, Huan; Yue, Hua-Mei; Yang, Xiao-Ge; Li, Chuang-Ju; Wei, Qi-Wei

    2016-10-01

    Germ cells are set aside from somatic cells early in embryogenesis, and are responsible for transmitting genetic information through generations. Vasa is a highly conserved germ cell marker across animal phyla, and widely used to label primordial germ cells. Dabry's sturgeon is a rare and endangered species distributed solely in the Yangtze River basin. Here, seven vasa isoforms, named Advasa1-7, were isolated and characterized in Dabry's sturgeon. RT-PCR and western blot analyses revealed that vasa mRNA and protein were mainly restricted to the testis and ovary, but exhibited sexually dimorphic expression. Cellular and subcellular localization uncovered that Advasa mRNA and protein displayed mitotic and meiotic expression in females, and mainly showed mitotic expression in males; surprisingly, they exhibited both cytoplasmic and nuclear expression in the ovarian germ cells, while showing exclusively cytoplasmic expression in the testicular germ cells. By microinjecting chimeric RNA consisting of the red fluorescent protein coding region and the Advasa 3'-untranslated region into embryos of Dabry's sturgeon, zebrafish and medaka, we demonstrated that it had the ability to visualize primordial germ cells (PGCs) in Dabry's sturgeon and zebrafish but not in medaka. It seemed that the machinery of vasa 3'UTR RNA localization was conserved between Dabry's sturgeon and ostariophysan, while possibly changed during the divergence of euteleosts and ostariophysan. Finally, Dabry's sturgeon PGCs moved on the yolk ball, and migrated toward the genital ridge via mesenchyme. Taken together, these results provide new information for vasa expression pattern and function, and lay a foundation for PGC cryopreservation and conservation of Dabry's sturgeon.

  5. Tissue-specific daily variation in the oxidative status of sturgeon (Acipenser naccarii) and rainbow trout (Oncorhynchus mykiss): a comparative study.

    PubMed

    Hidalgo, M C; Trenzado, C E; Furné, M; Beltrán, A; Manzaneda, C; García-Gallego, M; Domezain, A; Sanz, A

    2017-03-14

    The oxidative status is associated with animal lifespan, metabolism, activity and circadian rhythms. The objective of this work is to study the time course of the oxidative status over a daily cycle in the plasma, liver and brain, and the changes in the plasma cortisol levels of sturgeon and trout. The knowledge of daily oxidative status will provide a better understanding of the trout and sturgeon physiology and adequate maintenance and food supply of farmed fish in relation to photoperiod. Superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione transferase, DT-diaphorase activities, lipid peroxidation and cortisol were measured. Our results showed that the antioxidative enzyme activities and lipid peroxidation in the liver of trout and sturgeon changed through the day, with increased levels in lipid peroxidation of liver in the dark period for sturgeon. This could be related to the different activity time in both species, an issue to be taken into account when designing the guidelines of the maintenance of these species in fish farms. On the contrary, there was not clear influence of the daily rhythms on brain oxidative status. The higher efficiency of the antioxidant defences in the brain of sturgeon, which displays less lipid peroxidation and higher antioxidative activity, could be related to its longer life expectancy. The absence of any apparent daily rhythm in the plasma cortisol levels in sturgeon could indicate a lower susceptibility to stress, and that mechanisms involved in cortisol secretion in chondrosteans could be different from that described for teleosteans.

  6. Columbia River White Sturgeon (Acipenser Transmontanus) Early Life History and Genertics Study, August 1, 1984 to December 31, 1985 Final Report.

    SciTech Connect

    Brannon, Ernest L.

    1985-12-01

    Research on Columbia River white sturgeon has been directed at their early life history as it may apply to production and enhancement strategies for management of the species. The river environment in which sturgeon historically migrated, spawned, and reared has changed through development. Habitat changes are expected to precipitate genetic changes in the fish, as well as reduce the fitness in populations. Genetic analysis of samples taken from various locations over the length of the Columbia River have indicated that observed gene frequencies in all areas sampled were not in Hardy-Weinburg equilibrium, which could suggest that the general population is experiencing perturbation in the system. Analysis thus far has exposed few differences between samples from the lower, middle, and upper portions of the system. Allelic differences were identified in fish from the Roosevelt Lake, which may be evidence of unique characteristics among fish from that general area.

  7. Evaluation of lethal and non-lethal sampling methods for the detection of white sturgeon iridovirus infection in white sturgeon, Acipenser transmontanus (Richardson).

    PubMed

    Drennan, J D; Lapatra, S E; Samson, C A; Ireland, S; Eversman, K F; Cain, K D

    2007-06-01

    Pectoral fin tissue of white sturgeon was investigated as a potential non-lethal sample source for the detection of white sturgeon iridovirus (WSIV) infection. Histopathology and polymerase chain reaction (PCR) results using fin tissue were compared with the standard lethal histopathology sampling method that utilizes head tissue. Tissues for each of the three sampling methods were collected weekly for 8 weeks from individual sturgeon undergoing an experimental cohabitation challenge with fish infected with the Abernathy isolate of WSIV. Non-lethal fin histopathological evaluation did not reveal infection during the first 3 weeks of sampling, while non-lethal PCR and the lethal method were variable. However, all three sampling methods were equally capable of identifying infection from 4 to 8 weeks post-exposure. Of the survivors tested, all were negative by PCR and the lethal method, and only one fish was identified as being positive by non-lethal fin histopathology. In another experiment, all three sampling methods were applied to asymptomatic WSIV carriers in a case study conducted at the Kootenai Tribal Sturgeon Conservation Hatchery. Results showed that both lethal and non-lethal fin histopathology were equally effective in detecting infection, but PCR was unable to identify this strain of WSIV. Depending on the virus isolate, these results suggest that non-lethal sampling of fin tissue (histopathology or PCR) is comparable with the lethal sampling method at identifying WSIV infection once infection is established, and under certain circumstances may provide an alternative to lethal sampling.

  8. Distinguishing ovarian maturity of farmed white sturgeon (Acipenser transmontanus) by Fourier transform infrared spectroscopy: a potential tool for caviar production management.

    PubMed

    Lu, Xiaonan; Webb, Molly; Talbott, Mariah; Van Eenennaam, Joel; Palumbo, Amanda; Linares-Casenave, Javier; Doroshov, Serge; Struffenegger, Peter; Rasco, Barbara

    2010-04-14

    Fourier transform infrared spectroscopy (FT-IR, 4000-400 cm(-1)) was applied to blood plasma of farmed white sturgeon (N = 40) to differentiate and predict the stages of ovarian maturity. Spectral features of sex steroids (approximately 3000 cm(-1)) and vitellogenin (approximately 1080 cm(-1)) were identified. Clear segregation of maturity stages (previtellogenesis, vitellogenesis, postvitellogenesis, and follicular atresia) was achieved using principal component analysis (PCA). Progression of oocyte development in the late phase of vitellogenesis was also monitored using PCA based on changes in plasma concentrations of sex steroid and lipid content. The observed oocyte polarization index (PI, a measure of nuclear migration) was correlated with changes in plasma sex steroid levels revealed by FT-IR PCA results. A partial least squares (PLS) model predicted PI values within the range 0.12-0.40 (R = 0.95, SEP = 2.18%) from differences in spectral features. These results suggest that FT-IR may be a good tool for assessing ovarian maturity in farmed sturgeon and will reduce the need for the invasive ovarian biopsy required for PI determination.

  9. Can fatty acid and mineral compositions of sturgeon eggs distinguish between farm-raised versus wild white (Acipenser transmontanus) sturgeon origins in California? Preliminary report.

    PubMed

    DePeters, Edward J; Puschner, Birgit; Taylor, Scott J; Rodzen, Jeff A

    2013-06-10

    The objective was to investigate the potential of using fatty acid and mineral compositions of sturgeon eggs to distinguish their source, either farm-raised or wild fish. Trafficking of illegally obtained wild white sturgeon eggs is a major concern to the California Department of Fish and Game, but there is no forensic method to separate wild and farm-raised white sturgeon eggs. The extension of these findings in future work will be to use the fatty acid and mineral compositions as forensic indicators of caviar produced legally from farm raised sturgeon compared with illegal caviar produced from sturgeon poached from the wild. Samples (10) of sturgeon eggs were collected from a commercial aquaculture facility in the Sacramento Valley. Eggs from wild sturgeon (9) were obtained primarily from confiscations of illegally caught sturgeon by fish and game law enforcement personnel. The total lipid content of sturgeon eggs was analyzed for fatty acid composition. The most notable difference was the higher concentration (P<0.001) of C18:2n6 in farm raised eggs (6.5 mg/100g total lipid) than wild eggs (0.6 mg/100g total lipid) while other differences between fatty acids were smaller. Eicosapentaenoic acid (C20:5n3) was higher (P<0.02) in farm-raised (5.56 mg/100g) than wild (4.49 mg/100g). Docosahexaenoic acid (C22:6n3), C18:1 cis 9&10, and C20:4n6 were not different for origin of the eggs. Concentration of selenium was markedly higher (P<0.001) in eggs from wild sturgeon (10.0 mg/kg dry weight) than farm-raised sturgeon (2.7 mg/kg dry weight). Concentrations of iron, zinc, copper, phosphorus, sulfur, calcium, and potassium did not differ between farm-raised and wild eggs. Arsenic concentration in wild eggs was 3.3mg/kg dry weight whereas arsenic was not detected in the farm-raised eggs. Fatty acid and mineral compositions of eggs differed significantly between farm-raised and wild sturgeon and these should be investigated further as biological markers for forensic identification of caviar origin.

  10. Characterization of serum and mucosal antibody responses in white sturgeon (Acipenser transmontanus Richardson) following immunization with WSIV and a protein hapten antigen.

    PubMed

    Drennan, John D; Lapatra, Scott E; Swan, Christine M; Ireland, Sue; Cain, Kenneth D

    2007-09-01

    Serum and cutaneous mucus antibodies were monitored in white sturgeon for 15 weeks following intraperitoneal immunization. Ten fish were immunized (50 microg) with white sturgeon iridovirus (WSIV) or white sturgeon gonad (WSGO) tissue culture cells emulsified with or without FCA. An additional group was immunized with FITC:KLH+FCA. Fish were booster immunized at 6 weeks. Fish immunized with FITC:KLH+FCA produced significant serum antibodies to FITC by 6 weeks and this response peaked at 12 weeks (average titer 31,000). Mucosal antibodies to FITC were first detected at 12 weeks and significantly elevated by 15 weeks (average titer 18). Anti-WSIV antibody titers were detected in the serum by 9 weeks in fish immunized with WSIV and WSIV+FCA, but only a small number responded to immunization. At 15 weeks, four fish immunized with WSIV produced serum antibodies (average titer 838) and one fish immunized with WSIV+FCA had a serum titer of 1600. Mucosal anti-WSIV antibody titers of 8 and 16 were observed in two fish from the WSIV group at 12 weeks while four different fish from this group responded at 15 weeks (average titer 4). Western Blot using a monoclonal antibody confirmed immunoglobulin in mucus, and specificity to WSIV was further demonstrated by immunocytochemistry using serum from fish immunized with WSIV. Specific antibody was not detected in mucus of fish immunized with WSIV+FCA, WSGO, or WSGO+FCA. Collectively, these experiments demonstrate that white sturgeon can generate a specific antibody response following immunization, and is the first report showing mucosal immunoglobulin is present in this species.

  11. Columbia River White Sturgeon (Acipenser Transmontanus) Population Genetics and Early Life History Study, January 1, 1986 to December 31, 1986, Final Report.

    SciTech Connect

    Brannon, Ernest L.

    1986-12-01

    The 1986 Columbia River white sturgeon investigations continued to assess genetic variability of sturgeon populations isolated in various areas of the Columbia River, and to examine environmental factors in the habitat that may affect early life history success. Baseline data have been collected for three character sets. Twenty-eight loci have been analyzed for differences using electrophoresis, snout shapes were assessed for multivariate distinction, and scute counts have been examined as an index of variability. Fish that reside in the mid-Columbia and lower river have been sufficiently characterized by electrophoresis to compare with up-river areas. To date, few electrophoretic differences have been identified. However, Lake Roosevelt sturgeon sample size will be increased to determine if some of the observed differences from lower river fish are significant. Snout shape has been shown to be easily quantifiable using the digitizing technique. Scute count data initially indicate that variability exists within as well as between areas. Patterns of differentiation of one or more of these data sets may be used to formulate stock transplant guidelines essential for proper management or enhancement of this species. The historical habitat available to sturgeon in the Columbia River has changed through the development of hydroelectric projects. Dams have reduced the velocity and turbulence, and increased light penetration in the water column from less silt. These changes have affected the ability of sturgeon to feed and have made them more vulnerable to predation, which appear to have altered the ability of populations isolated in the reservoirs to sustain themselves. Present studies support the theory that both the biological and physical habitat characteristics of the Columbia River are responsible for reduced sturgeon survival, and justify consideration of enhancement initiatives above Bonneville to improve sturgeon reproductive success.

  12. 50 CFR 660.702 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) Sharks: common thresher shark (Alopias vulpinus) pelagic thresher shark (Alopias pelagicus) bigeye thresher shark (Alopias superciliosus) shortfin mako or bonito shark (Isurus oxyrinchus) blue shark...: Billfish/Swordfish: striped marlin (Tetrapturus audax) swordfish (Xiphias gladius) Sharks: common...

  13. Mid-Atlantic elasmobranchs: Suitable metal scouts?

    PubMed

    Torres, Paulo; da Cunha, Regina Tristão; Dos Santos Rodrigues, Armindo

    2017-02-05

    Heavy metals are a hazard to marine fauna and human health. In this study we assess stable isotopes and metal content in Prionace glauca and Isurus oxyrinchus and analyse these results within and among other species and across regions and geographical areas. Also, we evaluate their suitability, together with Raja clavata and Galeorhinus galeus, as Mid-Atlantic bioindicators. Prionace glauca and I. oxyrinchus shared the same trophic level in a pelagic food web and did not present significant differences between genders or metals, except for As. Arsenic and Hg accumulated while Cd and Pb were not detected. One I. oxyrinchus presented Hg values above regulatory limits. A high Hg exposure was associated with I. oxyrinchus since its maximum weekly intake was exceeded. Elasmobranchs can be used as metal sentinels, each presenting different key features which defines a good marine bioindicator, allowing long-term monitoring at different temporal and spatial scales.

  14. 50 CFR 660.702 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (Tetrapturus audax) swordfish (Xiphias gladius) Sharks: common thresher shark (Alopias vulpinus) pelagic thresher shark (Alopias pelagicus) bigeye thresher shark (Alopias superciliosus) shortfin mako or bonito shark (Isurus oxyrinchus) blue shark (Prionace glauca) Tunas: north Pacific albacore (Thunnus...

  15. 50 CFR 665.800 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    .... Sharks: pelagic thresher shark Alopias pelagicus. bigeye thresher shark Alopias superciliosus. common thresher shark Alopias vulpinus. silky shark Carcharhinus falciformis. oceanic whitetip shark Carcharhinus longimanus. blue shark Prionace glauca. shortfin mako shark Isurus oxyrinchus. longfin mako shark...

  16. 50 CFR 223.102 - Enumeration of threatened marine and anadromous species.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... desotoi Wherever found. 56 FR 49653; Sep 30, 1991 68 FR 13370; Mar 19, 2003. (3) Ozette Lake sockeye Oncorhynchus nerka U.S.A.- WA, including all naturally spawned populations of sockeye salmon in Ozette Lake and streams and tributaries flowing into Ozette Lake, Washington, as well as two artificial...

  17. 75 FR 69701 - Endangered Species; Receipt of Applications for Permit

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-15

    ... aquaculture practices, of white sturgeon, (Acipenser transmontanus), for the purpose of enhancement of the... scientific research. Applicant: Drexel University, Dept. of Biology, Philadelphia, PA; PRT- 26030A...

  18. Bioaccumulation of Heavy Metals and Microelements in Silver Bream (Brama brama L.), Northern Pike (Esox lucius L.), Sterlet (Acipenser ruthenus L.), and Common Carp (Cyprinus carpio L.) From Tisza River, Serbia.

    PubMed

    Štrbac, Snežana; Kašanin-Grubin, Milica; Jovančićević, Branimir; Simonović, Predrag

    2015-01-01

    The aim of this study was to determine the concentrations of Al, As, B, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, Sr, and Zn in liver, gills, gonads, and brain of four ecologically different fish species in Serbia: piscivorous northern pike, benthivorous sterlet and silver bream, and omnivorous common carp. Fish were caught at four sites along the stretch of the River Tisza in the Pannonian part of Serbia during October 2010. Results revealed that heavy metals and microelements with the highest values in fish samples were Fe, Al, and Zn. The highest concentration of heavy metals and microelements was recorded in omnivorous common carp, and organs that most intensively accumulated the greatest number of metals were liver and gills, whereas the locality did not exert a marked impact on level of bioaccumulation.

  19. 78 FR 69310 - Endangered and Threatened Species; Protective Regulations for the Gulf of Maine Distinct...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-19

    ... oxyrinchus). On February 6, 2012, we listed the Gulf of Maine DPS of Atlantic sturgeon as threatened under the Endangered Species Act (ESA). When a species is listed as threatened under the ESA, we are required to issue protective regulations under section 4(d) of the ESA. Such protective regulations...

  20. White Sturgeon Bibliography, 1985 Final Report.

    SciTech Connect

    Fickeisen, Duane H.

    1986-03-01

    This bibliography presents citations to the majority of published materials on white sturgeon (Acipenser transmontanus). The purpose was to assist in planning and implementing research on white sturgeon in the Columbia River system. (ACR)

  1. 76 FR 57717 - Endangered and Threatened Species; Take of Anadromous Fish

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-16

    ... different geographic populations and identify potential salmonid sources for introduction into the San... sturgeon (Acipenser medirostris) for scientific research purposes. NRSI will collect fish entrainment data... of the study are: to determine correlation of fish entrainment with river diversion flows,...

  2. The history of sturgeon in the Baltic Sea

    USGS Publications Warehouse

    Popovic, Danijela; Panagiotopoulou, Hanna; Baca, Mateusz; Stefaniak, Krzysztof; Mackiewicz, Pawel; Makowiecki, Daniel; King, Tim L.; Gruchota, Jakub; Weglenski, Piotr; Stankovic, Anna

    2014-01-01

    For the past 2000 years at least, A. o. oxyrinchus has been the dominant sturgeon in the Baltic Sea, indicating a much earlier origin than previously suggested. The most similar extant sturgeon populations to the extinct Baltic stock are those from the St John and St Lawrence rivers in Canada. These populations should be considered the best source of breeding material for the ongoing sturgeon restitution programmes in Poland and Germany.

  3. 75 FR 61424 - Endangered Species; File No. 15596

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-05

    ... sturgeon (Acipenser brevirostrum) for the purposes of enhancement. DATES: Written, telefaxed, or e-mail... educational display of five captive-bred, non-releaseable adult shortnose sturgeon. This display would be used to increase public awareness of the shortnose sturgeon and its status by educating the public...

  4. 75 FR 6184 - Endangered Species; File No. 14754

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-08

    ... form for a permit to import and take shortnose sturgeon (Acipenser brevirostrum) early life stages (ELS..., to conduct research on Atlantic and shortnose sturgeon. Dr. Wirgin is requesting to conduct a study to determine if early life-stages of Atlantic and shortnose sturgeon are sensitive to PCB...

  5. 77 FR 20590 - Ocean Dumping; Designation of Ocean Dredged Material Disposal Sites Offshore of Yaquina Bay, OR

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-05

    ... physical movement of sediment through the water column. All dredged material proposed for disposal will be... pelagic and demersal fish species, including salmon, green sturgeon, and flatfish, as well as Dungeness... southern green sturgeon (Acipenser medirostris) but is likely to adversely affect Oregon Coast coho...

  6. 78 FR 18963 - Endangered and Threatened Species; Take of Anadromous Fish

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-28

    ... population segment of North American (SDPS) green sturgeon (Acipenser medirostris). ] Authority Scientific... juvenile SDPS green sturgeon associated with research activities in the Central Valley, California. Incidental mortality of SDPS green sturgeon is not expected to occur and therefore none is requested...

  7. 78 FR 65249 - Endangered and Threatened Wildlife and Plants; 12-Month Finding and Proposed Endangered Listing...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-31

    ... Animals to list 15 species of sturgeon (Acipenser naccarii--Adriatic sturgeon; A. sturio--European... endangered species as ``any species which is in danger of extinction throughout all or a significant portion... ``endangered species'' to be one that is presently in danger of extinction. A ``threatened species,'' on...

  8. 75 FR 54647 - Revision of Information Collection; Non-Use Valuation Survey, Klamath Basin; Correction and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-08

    ...), steelhead trout (Oncorhynchus mykiss), green sturgeon (Acipenser medirostris), Pacific lamprey (Lampetra... to Klamath Basin tribes (e.g., salmon, sturgeon, lamprey, eulachon), and some are at low levels of abundance or Endangered Species Act-listed (e.g., spring Chinook, lamprey, coho, eulachon). Studies on...

  9. 76 FR 9046 - Non-Use Valuation Survey, Klamath Basin; Thirty-Day Notice Requesting Additional Public Comments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-16

    ... (Oncorhynchus mykiss), green sturgeon (Acipenser medirostris), Pacific lamprey (Lampetra tridentate), and... Basin tribes (e.g., salmon, sturgeon, lamprey, eulachon), and some are at low levels of abundance or Endangered Species Act-listed (e.g., spring Chinook, lamprey, coho, eulachon). Studies on the...

  10. Enhancement of lake sturgeon conservation through feeding management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lake sturgeon (Acipenser fulvescens), listed as threatened under the State of Michigan’s Endangered Species Act, has high ecological and economical values as a native benthivore. Many efforts for enhancing stocking have been implemented to restore wild populations. For current stocking programs, lak...

  11. 77 FR 51767 - Endangered and Threatened Wildlife; 90-Day Finding on a Petition To List Five Species of Sturgeon...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-27

    ... WildEarth Guardians and Friends of Animals to list 15 species of sturgeon (Acipenser naccarii--Adriatic..., Norway, Portugal, Spain, Tunisia and the United Kingdom. According to the petitioner and IUCN, its... sites. The petition also cites the 16th Meeting of the CITES Animals Committee in December 2000,...

  12. First record predation on white sturgeon eggs by sympatric fishes

    USGS Publications Warehouse

    Miller, A.I.; Beckman, L.G.

    1996-01-01

    We report the occurrence of white sturgeon Acipenser transmontanus eggs in guts of four species of fish from the Columbia River. Three of the species—northern squawfish Ptychocheilus oregonensis, largescale sucker Catostomus macrocheilus, and prickly sentpin Cottus asper—are native to the river and one, common carp Cvprinus carpio, is exotic.

  13. Southwest Mississippi Tributaries Study Area Environmental Inventory; Wildlife Resources.

    DTIC Science & Technology

    1985-09-01

    flycatcher (Empidonax virescens) X Eastern phoebe (Sayornis phoebe) X X Vermillion flycatcher (Pyrocephalus rubinus) X Great crested flycatcher (Myiarchus...34 " ,". - . ..../ :_’± ,’. -’ Table 26 Endangered Vertebrates of Mississippi Fish Southern redbelly dace (Phoxinus erythrogaster) Bayou darter (Etheostoma rubrum)* Crystal... darter (Ammocrypta aspreZZa)* Frecklebelly madtom (Noturus munitus) Atlantic sturgeon (Acipenser oxyrhynchus) Undescribed Tombigbee River sturgeon

  14. 50 CFR 226.219 - Critical habitat for the Southern Distinct Population Segment of North American Green Sturgeon...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 10 2012-10-01 2012-10-01 false Critical habitat for the Southern Distinct Population Segment of North American Green Sturgeon (Acipenser medirostris). 226.219 Section 226.219 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND...

  15. 50 CFR 226.219 - Critical habitat for the Southern Distinct Population Segment of North American Green Sturgeon...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 9 2011-10-01 2011-10-01 false Critical habitat for the Southern Distinct Population Segment of North American Green Sturgeon (Acipenser medirostris). 226.219 Section 226.219 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND ATMOSPHERIC...

  16. Chesapeake Bay Low Freshwater Inflow Study. Biota Assessment. Phase I. Volume I.

    DTIC Science & Technology

    1980-08-01

    shark x x Sp Vr~ 𔄂Vgena hammerhead shark x x Raja ecjiwiteria clearnose skate x Rhinoptera bonaus cownose ray K K *Acipenser oxyrhynchuz Atlantic...Marsh. Uae Sm a I toUha"e Abundanc Fihspecies present I ~ r j *Pe0troffiv~on TW,nus sea lamIpreyt Carcharhinus leucas bull shark x cacahnsmlprisandbar

  17. Plasticity of trophic interactions among sharks from the oceanic south-western Indian Ocean revealed by stable isotope and mercury analyses

    NASA Astrophysics Data System (ADS)

    Kiszka, Jeremy J.; Aubail, Aurore; Hussey, Nigel E.; Heithaus, Michael R.; Caurant, Florence; Bustamante, Paco

    2015-02-01

    Sharks are a major component of the top predator guild in oceanic ecosystems, but the trophic relationships of many populations remain poorly understood. We examined chemical tracers of diet and habitat (δ15N and δ13C, respectively) and total mercury (Hg) concentrations in muscle tissue of seven pelagic sharks: blue shark (Prionace glauca), short-fin mako shark (Isurus oxyrinchus), oceanic whitetip shark (Carcharhinus longimanus), scalloped hammerhead shark (Sphyrna lewini), pelagic thresher shark (Alopias pelagicus), crocodile shark (Pseudocarcharias kamoharai) and silky shark (Carcharhinus falciformis), from the data poor south-western tropical Indian Ocean. Minimal interspecific variation in mean δ15N values and a large degree of isotopic niche overlap - driven by high intraspecific variation in δ15N values - was observed among pelagic sharks. Similarly, δ13C values of sharks overlapped considerably for all species with the exception of P. glauca, which had more 13C-depleted values indicating possibly longer residence times in purely pelagic waters. Geographic variation in δ13C, δ15N and Hg were observed for P. glauca and I. oxyrinchus. Mean Hg levels were similar among species with the exception of P. kamoharai which had significantly higher Hg concentrations likely related to mesopelagic feeding. Hg concentrations increased with body size in I. oxyrinchus, P. glauca and C. longimanus. Values of δ15N and δ13C varied with size only in P. glauca, suggesting ontogenetic shifts in diets or habitats. Together, isotopic data indicate that - with few exceptions - variance within species in trophic interactions or foraging habitats is greater than differentiation among pelagic sharks in the south-western Indian Ocean. Therefore, it is possible that this group exhibits some level of trophic redundancy, but further studies of diets and fine-scale habitat use are needed to fully test this hypothesis.

  18. The species and heme pocket properties of sturgeon hemoglobins upon interaction with N-dodecyl trimethylammonium bromide.

    PubMed

    Ariaeenejad, Shohreh; Moosavi-Movahedi, Ali A; Kavousi, Kaveh; Dayer, Mohammad Reza; Hong, Jun; Yousefi, Reza; Sheibani, Nader; Habibi-Rezaei, Mehran

    2014-01-01

    The variations in fish hemoglobin (Hb) structures play a vital role in their respiratory performance under various environmental conditions and are impacted by their physiological properties. The major hemoglobins from two species of sturgeon were studied upon interaction with n-dodecyl trimethyl ammonium bromide (DTAB) using the UV-vis absorption, circular dichroism (CD), fluorescence spectroscopy, and oxygen affinity measurement methods as well as chemometric analysis. The UV-Vis absorption spectra between 500 and 650 nm was used to identify each species of hemoglobin, and to show that the concentration of oxyHb and metHb decreases, while that of deoxyHb increases upon interaction with DTAB. Both reduced oxyHb and oxidized hemichrome of the two Hbs were studied to obtain information about the DTAB efects on their structural features. The circular dichroism (CD) was utilized to obtain secondary structure and compactness for Hb upon interaction with DTAB. Binding of DTAB molecules induced the unfolding of Hb, and was accompanied with exposure of the heme pocket facilitating its oxidation. The differences between unfolding processes for the two Acipenser species were indicated by fluorescence spectroscopy. The chemometric analysis of Hbs was investigated upon interaction with DTAB under titration, using fluorescence spectra allowing determination of the number of components and mole fractions of the oxidized Hb. Our data showed that Acipenser persicus Hb had a more hyperchromic character, more surface area, more loosely folded structure, and therefore, exposed region of heme group compared with Acipenser stellatus oxyHb. In addition, with increasing DTAB the transition of Acipenser stellatus oxyHb to the state of hemichrome occurred at a slower speed than Acipenser persicus oxyHb, and finally more oxygen affinity and compactness. Our results suggest that these differences aroused from the inherent differences between the heme groups which fulfil a potentially

  19. Monsters of the sea serpent: parasites of an oarfish, Regalecus russellii.

    PubMed

    Kuris, Armand M; Jaramillo, Alejandra G; McLaughlin, John P; Weinstein, Sara B; Garcia-Vedrenne, Ana E; Poinar, George O; Pickering, Maria; Steinauer, Michelle L; Espinoza, Magaly; Ashford, Jacob E; Dunn, Gabriela L P

    2015-02-01

    Examination of a small portion of the viscera of an oarfish ( Regalecus russellii ) recovered from Santa Catalina Island, southern California, revealed numerous tetraphyllidean tapeworm plerocercoids, Clistobothrium cf. montaukensis; 2 juvenile nematodes, Contracaecum sp.; and a fragment of an adult acanthocephalan, family Arhythmacanthidae. This suggests that the fish was relatively heavily parasitized. The presence of larval and juvenile worms suggests that oarfish are preyed upon by deep-swimming predators such as the shortfin mako shark, Isurus oxyrinchus , known to be a definitive host for the adult tapeworm, and also by diving mammals such as sperm whales, Physeter catodon L., hosts of Contracaecum spp. nematodes.

  20. Tracing the first steps of American sturgeon pioneers in Europe

    USGS Publications Warehouse

    Ludwig, A.; Arndt, U.; Lippold, S.; Benecke, N.; Debus, L.; King, T.L.; Matsumura, S.

    2008-01-01

    Background. A Baltic population of Atlantic sturgeon was founded ???1,200 years ago by migrants from North America, but after centuries of persistence, the population was extirpated in the 1960s, mainly as a result of over-harvest and habitat alterations. As there are four genetically distinct groups of Atlantic sturgeon inhabiting North American rivers today, we investigated the genetic provenance of the historic Baltic population by ancient DNA analyses using mitochondrial and nuclear markers. Results. The phylogeographic signal obtained from multilocus microsatellite DNA genotypes and mitochondrial DNA control region haplotypes, when compared to existing baseline datasets from extant populations, allowed for the identification of the region-of-origin of the North American Atlantic sturgeon founders. Moreover, statistical and simulation analyses of the multilocus genotypes allowed for the calculation of the effective number of individuals that originally founded the European population of Atlantic sturgeon. Our findings suggest that the Baltic population of A. oxyrinchus descended from a relatively small number of founders originating from the northern extent of the species' range in North America. Conclusion. These results demonstrate that the most northerly distributed North American A. oxyrinchus colonized the Baltic Sea ???1,200 years ago, suggesting that Canadian specimens should be the primary source of broodstock used for restoration in Baltic rivers. This study illustrates the great potential of patterns obtained from ancient DNA to identify population-of-origin to investigate historic genotype structure of extinct populations. ?? 2008 Ludwig et al; licensee BioMed Central Ltd.

  1. Bioaccumulation of Cd, Pb and Zn in the edible and inedible tissues of three sturgeon species in the Iranian coastline of the Caspian Sea.

    PubMed

    Mashroofeh, Abdulreza; Bakhtiari, Alireza Riyahi; Pourkazemi, Mohammad; Rasouli, Sana

    2013-01-01

    The accumulations of Cd, Pb and Zn were determined in edible and inedible tissues of Persian sturgeon (Acipenser persicus; n=27), stellate sturgeon (Acipenser stellatus; n=5) and beluga (Huso huso; n=4) collected from coastal waters of the South Caspian Sea from March to April 2011. Concentrations of metals evaluated in the caviar, muscle, liver, kidney, gills, ovary and heart of the three species of sturgeons have been assessed using the flame and graphite furnace atomic absorption spectrophotometer. Concentrations of Zn, Pb and Cd in the edible and inedible tissues were apparently different among the three species of sturgeons. Especially, beluga heart showed the highest concentrations of Zn and Pb and Cd in Persian sturgeon liver. The analyzed metals were found in the caviar and muscle samples of Persian sturgeon and likewise muscle samples two other sturgeon species at mean concentrations under the permissible limits proposed by MAFF (2000).

  2. The Environmental Evaluation Work Group: FY 1979 Studies of the Winter Navigation Demonstration Program, St. Lawrence River Fisheries Study

    DTIC Science & Technology

    1979-07-31

    marinus - Sea Lamprey X X - Acipenser fulvescens - Lake sturgeon X X X Lepisosteus osseus - Longnose gar X X X - Amia calva - Bowfin X X M,T Tb Anguilla...Growth, Feeding Ecology , Larval Fish, Spawning Areas, Benthic Invertebrates 19. ABSTRACT (Continue on revers if necesry and identify by block number...2) determine the population structure, relative growth and feeding ecology of northern pike, yellow perch, largemouth bass, smallmouth bass, and (3

  3. A validation of intracellular pH measurements in fish exposed to hypercarbia: the effect of duration of tissue storage and efficacy of the metabolic inhibitor tissue homogenate method.

    PubMed

    Baker, D W; May, C; Brauner, C J

    2009-07-01

    This study assessed the effect of tissue storage duration and accuracy of the metabolic inhibitor tissue homogenate (MITH) method on intracellular pH (pHi) values of tissues of white sturgeon Acipenser transmontanus during hypercarbia. No effect of storage in liquid nitrogen of up to 30 days was observed and MITH appears appropriate for measurement of pH in fish exposed to up to 10% CO2 (10000 Pa pCO2).

  4. Diagnosis of an unidentified sturgeon species using the complete mitochondrial DNA.

    PubMed

    Yu, Jeong-Nam; Kwak, Myounghai; Kweon, Seon-Man; Kwon, O-Nam

    2015-01-01

    A sturgeon of unknown species of 11 kg body weight was caught in Gosung-gun, Gangwon Province, Korea (38°17'10.67″N, 128°33'20.28″E). The morphological characteristics were similar to species of the genus Acipenser such as Acipenser medirostris, A. schrenckii and A. baerii, but it was not an obvious match. To identify the species using genetic tools, we analysed the complete mitogenome of this unidentified sturgeon, and found it to comprise 16,526 bp. The genome encoded 2 rRNAs, 22 tRNAs, 13 protein-coding genes and 1 control region. The nucleotide divergence between the complete mitogenome of the unidentified sturgeon and those of four Acipenser spp. (A. transmontanus, A. dabryanus, A. schrenckii and A. baerii) was 0.736%, 3.875%, 0.085% and 5.580%, respectively. This study suggests that the unidentified sturgeon is able to predict the least maternal lines with A. schrenckii.

  5. Effects of trophic ecology and habitat use on maternal transfer of contaminants in four species of young of the year lamniform sharks.

    PubMed

    Lyons, Kady; Carlisle, Aaron; Preti, Antonella; Mull, Christopher; Blasius, Mary; O'Sullivan, John; Winkler, Chuck; Lowe, Christopher G

    2013-09-01

    Organic contaminant and total mercury concentrations were compared in four species of lamniform sharks over several age classes to examine bioaccumulation patterns and gain insights into trophic ecology. Contaminants found in young of the year (YOY) sharks were assumed to be derived from maternal sources and used as a proxy to investigate factors that influence maternal offloading processes. YOY white (Carcharodon carcharias) and mako (Isurus oxyrinchus) sharks had comparable and significantly higher concentrations of PCBs, DDTs, pesticides, and mercury than YOY thresher (Alopias vulpinus) or salmon (Lamna ditropis) sharks. A significant positive relationship was found between YOY contaminant loads and maternal trophic position, suggesting that trophic ecology is one factor that plays an important role in maternal offloading. Differences in organic contaminant signatures and contaminant concentration magnitudes among species corroborated what is known about species habitat use and may be used to provide insights into the feeding ecology of these animals.

  6. Permanent genetic resources added to Molecular Ecology Resources Database 1 October 2010-30 November 2010.

    PubMed

    Agostini, Cecilia; Agudelo, P A; Bâ, K; Barber, P A; Bisol, Paolo Maria; Brouat, C; Burgess, Treena I; Calves, I; Carrillo Avila, Mauricio; Chow, S; Cordes, Lisa; Da Silva, D; Dalecky, A; De Meester, L; Doadrio, Ignacio; Dobigny, G; Duplantier, J M; Evison, Sophie E F; Ford, Rebecca; Fresneau, Dominique; Galetti, Pedro M; Gauthier, P; Geldof, S; Granjon, L; Guérin, F; St J Hardy, Giles E; Hernandez Escobar, Carlos; Hima, K; Hu, Juan; Huang, Luqi; Humeau, L; Jansen, B; Jaquemet, S; Jiang, Zhi-Qiang; Jung, Sung-Ju; Kim, Bong-Seok; Kim, Cheol-Hee; Kim, Jong-Oh; Lai, Choay-Hoong; Laroche, J; Lavergne, E; Lawton-Rauh, A; Le Corre, M; Leach, M M; Lee, Jehee; Leo, Audrey E; Lichtenzveig, Judith; Lin, Lin; Linde, Celeste C; Liu, Shu-Fang; Marino, Ilaria A M; McKeown, Niall J; Nohara, K; Oh, Myung-Joo; Okamoto, H; Oliver, Richard; Olivera Angel, Martha; Ornelas-García, Claudia Patricia; Orsini, L; Ostos Alfonso, Henry; Othman, A S; Papetti, Chiara; Patarnello, Tomaso; Pedraza-Lara, Carlos; Piller, Kyle R; Poteaux, Chantal; Requier, J-B; Roziana, M K; Semba, Y; Sembene, M; Shah, Ramisah M; Shahril, A R; Shao, Aijuan; Shaw, Paul W; Song, Liangke; Souza Ferreira, Ronara; Su, Yong-Quan; Suzuki, N; Tatard, C; Taylor, Katherine M; Taylor, Paul W J; Thiam, M; Valbuena, Ruben; Wang, He; Yang, Byung-Gyoo; Yuan, Qingjun; Zajonz, U; Zane, Lorenzo; Zhu, Ling; Zhuang, Zhi-Meng; Zulaiha, A R

    2011-03-01

    This article documents the addition of 277 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Ascochyta rabiei, Cambarellus chapalanus, Chionodraco hamatus, Coptis omeiensis, Cynoscion nebulosus, Daphnia magna, Gerbillus nigeriae, Isurus oxyrinchus, Lates calcarifer, Metacarcinus magister, Oplegnathus fasciatus, Pachycondyla verenae, Phaethon lepturus, Pimelodus grosskopfii, Rotylenchulus reniformis, Scomberomorus niphonius, Sepia esculenta, Terapon jarbua, Teratosphaeria cryptica and Thunnus obesus. These loci were cross-tested on the following species: Austropotamobius italicus, Cambarellus montezumae, Cambarellus puer, Cambarellus shufeldtii, Cambarellus texanus, Chionodraco myersi, Chionodraco rastrospinosus, Coptis chinensis, Coptis chinensis var. brevisepala, Coptis deltoidea, Coptis teeta, Orconectes virilis, Pacifastacus leniusculus, Pimelodus bochii, Procambarus clarkii, Pseudopimelodus bufonius, Rhamdia quelen, Sepia andreana, Sepiella maindroni, Thunnus alalunga, Thunnus albacares, Thunnus maccoyii, Thunnus orientalis, Thunnus thynnus and Thunnus tonggol.

  7. Bioaccumulation and biomagnification of total mercury in four exploited shark species in the Baja California Peninsula, Mexico.

    PubMed

    Maz-Courrau, A; López-Vera, C; Galván-Magaña, F; Escobar-Sánchez, O; Rosíles-Martínez, R; Sanjuán-Muñoz, A

    2012-02-01

    The present study determined the average mercury bioaccumulation in the muscle tissue of four shark species (Carcharhinus falciformis, Prionace glauca, Sphyrna zygaena and Isurus oxyrinchus) captured in the Baja California Peninsula. We also evaluated biomagnification of some prey consumed by sharks. All sharks' species had mercury levels over the limit specified by the Mexican government for human consumption. Blue shark (P. glauca) presented highest mercury values (1.96 ± 1.48 μg/g Hg d.w.) and it was the unique specie that showed a negative correlation with mercury content (Rs = -0.035, p = 0.91). Scomber japonicus was the prey with high content of mercury (0.57 ± 0.02 μg/g).

  8. Hydrology and water resources in Caspian Sea

    NASA Astrophysics Data System (ADS)

    Haddadi Moghaddam, Kourosh

    2016-10-01

    Precipitation is the main driver of the water balance variability of the water over space and time, and changes in precipitation have very important implications for hydrology and water resources. Variations in precipitation over daily, seasonal, annual, and decadal time scales influence hydrological variability over time in a catchment. Flood frequency is affected by changes in the year-to-year variability in precipitation and by changes in short-term rainfall properties. Desiccation of the Caspian Sea is one of the world's most serious ecosystem catastrophes. The Persian Sturgeon (Acipenser persicus) caught under 10 m depth using bottom trawl net by research vessel during winter 2012, summer and winter 2013 and spring 2014 in east, central and west of southern parts of Caspian Sea, then, their diets were investigated. During 136 trawling in the aimed seasons, Persian sturgeon with 1 to 2 years old and 179.67 × 0.2 g (body weight) and 29.97 ± 0.4 cm (Total length) captured. Examination of stomach contents in the sturgeon specimens revealed that the food spectrum was composed of bony fishes (Neogobius sp., Atherina sp. and Clupeonella delicatula), invertebrates belonging to the family Ampharetidae polychaeta worms including (Hypanai sp. and Nereis diversicolor), various crustaceans (Gammarus sp. and Paramysis sp.). Investigation on stomach contents of sturgeon Acipenser persicus caught under 10 m depth in 2012 to 2013 surveys showed that there is significant difference in the consumed food. The most food diversity have been observed in winter 2013, also Polychaeta is the primary consumed food and crustacean is the secondary one (P > 0.05), no new types of food (such as bony fishes or benthics) have been observed on food chain of Acipenser persicus and shows no significant difference (P > 0.05).

  9. Cloning HSP70 and HSP90 genes of kaluga (Huso dauricus) and the effects of temperature and salinity stress on their gene expression.

    PubMed

    Peng, Guogan; Zhao, Wen; Shi, Zhenguang; Chen, Huirong; Liu, Yang; Wei, Jie; Gao, Fengying

    2016-03-01

    The genes encoding HSP70 and HSP90 proteins were isolated from kaluga by homologous cloning and rapid amplification of complementary DNA (cDNA) ends (RACE). HSP70 (GenBank accession no. KP050541) and HSP90 (GenBank accession no. KP050542) cDNAs were composed of 2275 and 2718 bp and encoded polypeptides of 650 and 725 amino acids, respectively. Basic Local Alignment Search Tool (BLAST) analysis showed that HSP70 and HSP90 of kaluga shared high identities with those of Acipenser ruthenus, Acipenser schrenckii, and Acipenser baerii (98-99 %). Fluorescent real-time RT-PCR under unstressed conditions revealed that HSP70 and HSP90 were expressed in 11 different tissues of kaluga. Messenger RNA (mRNA) expressions of both HSP70 and HSP90 were highest in the intestine and lowest in the muscle. In addition, the patterns of mRNA expression of HSP70 and HSP90 were similar, although the level of expression was more in HSP90 than in HSP70 (P < 0.05).We also analyzed patterns of HSP70 and HSP90 expression in the muscle, gill, and liver of kaluga under different combinations of temperature and salinity stress, including temperatures of 4,10, 25, and 28 °C at 0 ppt salinity, and salinities of 10, 20, 30, and 40 ppt at 16 °C, where 16 °C at 0 ppt (parts per thousand) served as the control. We found that levels of mRNA expression of both HSP70 and HSP90 were highest at 4 °C in the muscle, gill, and liver and changed little with salinity stress. These results increase understanding of the mechanisms of stress response of cold freshwater fish.

  10. Length changes in white sturgeon larvae preserved in ethanol or formaldehyde

    USGS Publications Warehouse

    Bayer, J.M.; Counihan, T.D.

    2001-01-01

    We examined the effects of two preservatives on the notochord and total lengths of white sturgeon (Acipenser transmontanus) larvae. White sturgeon larvae that were one, seven, and 14 days old were measured live and then preserved in 95% ethanol or 10% formaldehyde. Length changes were then determined at 20 and 95 days after preservation. We found mean length changes ranging from 0.4% to 3.4% shrinkage. Length changes varied with preservative, age of larvae, and length of time preserved. Constant length correction factors are provided for 10% formaldehyde or 95% ethanol valid for larvae between 1 and 14 days old preserved for less than 100 days.

  11. Molecular analysis of phylogeographic subspecies in three Ponto-Caspian sturgeon species

    PubMed Central

    Dudu, Andreea; Georgescu, Sergiu Emil; Costache, Marieta

    2014-01-01

    Sturgeons (Order Acipenseriformes) represent an extremely valuable natural resource that is now facing depletion. In the current study we evaluate if the traditional classification in subspecies of Acipenser gueldenstaedtii, Acipenser stellatus and Huso huso, endemic to Ponto-Caspian region is sustained by molecular analysis and if these represent Evolutionary Significant Units (ESUs) that should be managed separately in conservation programs. To examine the classification of taxonomic entities we sequenced a fragment of the mitochondrial control region in case of three sturgeon species that inhabit the North-western of Black Sea and migrate for reproduction in the Lower Danube. Beside these sequences, we used previously published sequences from sturgeon individuals sampled in the Black Sea, Azov Sea and Caspian Sea. We determined the genetic diversity and genetic differentiation, conducted a Population Aggregation Analysis (PAA) and inferred an intraspecific molecular phylogeny and haplotype network. The results indicated a low level of genetic differentiation between the geographically designated subspecies and did not support a significant divergence or reciprocal monophyly between them. Our results confirm previous genetic studies with smaller samples sizes, but additional analyses including nuclear markers should be conducted for proper recommendations aiming at the development of conservation programs. PMID:25249783

  12. Denaturation and intermediates study of two sturgeon hemoglobins by n-dodecyl trimethylammonium bromide

    PubMed Central

    Ariaeenejad, Shohreh; Habibi-Rezaei, Mehran; Kavousi, Kaveh; Jamili, Shahla; Fatemi, Mohammad Reza; Hong, Jun; Poursasan, Najmeh; Sheibani, Nader; Moosavi-Movahedi, Ali. A.

    2013-01-01

    Varieties of hemoglobin (Hb) forms exist in fish, which are usually well adapted to the different ecological conditions or various habitats. In the current study, Hbs from two Sturgeon species of the Southern Caspian Sea Basin were purified and studied upon interaction with n-dodecyl trimethylammonium bromide (DTAB; as a cationic surfactant) by various methods including UV-visible absorption, dynamic light scattering (DLS), and ANS fluorescence spectrophotometry. The chemometric analysis of Hbs was investigated upon interaction with DTAB under titration, using UV-visible absorption spectra. The chemometric resolution techniques were used to determine the number of the components and mole fraction of the oxidized Hbs. These results provided the evidence for the existence of three different molecular components including native (N), intermediate (I) and denatured (D) in sturgeon Hbs. According to the distribution of intermediates, which were broadened in a range of DTAB concentration, the aggregation states, DLS experiments, and thermal stability (Tm obtained by differential scanning calorimetry (DSC)), the Acipenser stellatus Hb was more stable compared to Acipenser persicus Hb. These results demonstrate a significant relationship between the stability of fish Hbs and the habitat depth requirements. PMID:23142155

  13. Molecular identification of iridoviruses infecting various sturgeon species in Europe.

    PubMed

    Bigarré, L; Lesne, M; Lautraite, A; Chesneau, V; Leroux, A; Jamin, M; Boitard, P M; Toffan, A; Prearo, M; Labrut, S; Daniel, P

    2017-01-01

    Iridoviridae are known to cause disease in sturgeons in North America. Here, histological and molecular methods were used to screen for this family of virus in sturgeons from various European farms with low-to-high morbidity. Some histological samples revealed basophilic cells in the gill and labial epithelia, strongly suggesting the accumulation of iridovirus particles. Newly developed generic PCR tests targeting the major capsid protein (MCP) gene of sturgeon iridoviruses identified in North America, namely the white sturgeon iridovirus and the Namao virus (NV), produced positive signals in most samples from four sturgeon species: Russian (Acipenser gueldenstaedtii), Siberian (A. baerii), Adriatic (A. naccarii) and beluga (Huso huso). The sequences of the PCR products were generally highly similar one another, with nucleotide identities greater than 98%. They were also related to (74-88%), although distinct from, American sturgeon iridoviruses. These European viruses were thus considered variants of a single new virus, provisionally named Acipenser iridovirus-European (AcIV-E). Moreover, three samples infected with AcIV-E showed genetic heterogeneity, with the co-existence of two sequences differing by five nucleotides. One of our European samples carried a virus distinct from AcIV-E, but closely related to NV identified in Canada (95%). This study demonstrates the presence of two distinct sturgeon iridoviruses in Europe: a new genotype AcIV-E and an NV-related virus.

  14. Trophic influences on mercury accumulation in top pelagic predators from offshore New England waters of the northwest Atlantic Ocean.

    PubMed

    Teffer, Amy K; Staudinger, Michelle D; Taylor, David L; Juanes, Francis

    2014-10-01

    Trophic pathways and size-based bioaccumulation rates of total mercury were evaluated among recreationally caught albacore tuna (Thunnus alalunga), yellowfin tuna (Thunnus albacares), shortfin mako shark (Isurus oxyrinchus), thresher shark (Alopias vulpinus), and dolphinfish (Coryphaena hippurus) from offshore southern New England waters of the northwest Atlantic Ocean between 2008 and 2011. Mercury concentrations were highest in mako (2.65 ± 1.16 ppm) and thresher sharks (0.87 ± 0.71 ppm), and significantly lower in teleosts (albacore, 0.45 ± 0.14 ppm; yellowfin, 0.32 ± 0.09 ppm; dolphinfish, 0.20 ± 0.17 ppm). The relationship between body size and mercury concentration was positive and linear for tunas, and positive and exponential for sharks and dolphinfish. Mercury increased exponentially with δ (15)N values, a proxy for trophic position, across all species. Results demonstrate mercury levels are positively related to size, diet and trophic position in sharks, tunas, and dolphinfish, and the majority of fishes exhibited concentrations greater than the US EPA recommended limit.

  15. The effect of mako sharkskin on laminar flow separation

    NASA Astrophysics Data System (ADS)

    Bradshaw, Michael; Lang, Amy; Motta, Philip; Habegger, Maria; Hueter, Robert

    2013-11-01

    Many animals possess effective performance enhancing mechanisms, such as the denticles found on the skin of the shortfin mako shark (Isurus oxyrinchus). The shortfin mako, one of the fastest sharks on the planet, is covered by small, tooth-like scales that vary in flexibility over the body. Previous biological findings have shown that the scales increase in flexibility from the leading to trailing edge over the pectoral fin as well as on various sections of the body. It is believed that the scale bristling may provide a mechanism for flow separation control that leads to decreased drag and increased maneuverability. This study involved testing a left pectoral fin of a shortfin mako shark as well as a cylinder with a sharkskin specimen applied circumferentially in a water tunnel facility under static, laminar conditions. Digital Particle Image Velocimetry (DPIV) was used to characterize the flow over the surfaces. Various Reynolds numbers were tested for both configurations, as well as several AOAs for the pectoral fin. The flow over the fin and cylinder were compared to a painted fin and a smooth PVC cylinder, respectively. The study found that the shark scales do, in fact, help to control flow separation. However, in order for the scales to bristle and trap the reversing flow, a certain magnitude of reversed flow and shear is required. This phenomenon seems to be most effective at near stall conditions and at higher Reynolds numbers. Support from REU grant 1062611 is greatfully acknowledged.

  16. Stable Isotope Analysis of Extant Lamnoid Shark Centra: A New Tool in Age Determination?

    NASA Astrophysics Data System (ADS)

    Labs, J.

    2003-12-01

    The oxygen isotopes of fourteen vertebral centra from ten extant lamnoid sharks (including Carcharodon carcharias [great white], Isurus paucus [longfin mako], and Isurus oxyrinchus [shortfin mako]) were sampled and measured along the growth axis to determine the periodicity of incremental growth represented in the centra. As part of the internal (endochondral) skeleton, shark centra are composed initially of hyaline cartilage, which then secondarily ossifies during ontogeny forming calcified hydroxyapatite bone. The incremental growth of shark centra forms definite growth rings, with darker denser portions being deposited during slower growth times (i.e., winter) and lighter portions being deposited during more rapid growth (i.e., summer). Thus, shark centra, whether they are extant or extinct, are characterized by clearly delineated incremental growth couplets. The problem with this general rule is that there are several factors in which the growth of these couplets can vary depending upon physical environment (including temperature and water depth), food availability, and stress. The challenge for paleobiological interpretations is how to interpret the periodicity of this growth. It can generally be assumed that these bands are annual, but it is uncertain the extent to which exceptions to the rule occur. Stable isotopic analysis provides the potential to independently determine the periodicity of the growth increments and ultimately the ontogenetic age of an individual.

  17. Movable shark scales act as a passive dynamic micro-roughness to control flow separation.

    PubMed

    Lang, Amy W; Bradshaw, Michael T; Smith, Jonathon A; Wheelus, Jennifer N; Motta, Philip J; Habegger, Maria L; Hueter, Robert E

    2014-09-01

    Shark scales on fast-swimming sharks have been shown to be movable to angles in excess of 50°, and we hypothesize that this characteristic gives this shark skin a preferred flow direction. During the onset of separation, flow reversal is initiated close to the surface. However, the movable scales would be actuated by the reversed flow thereby causing a greater resistance to any further flow reversal and this mechanism would disrupt the process leading to eventual flow separation. Here we report for the first time experimental evidence of the separation control capability of real shark skin through water tunnel testing. Using skin samples from a shortfin mako Isurus oxyrinchus, we tested a pectoral fin and flank skin attached to a NACA 4412 hydrofoil and separation control was observed in the presence of movable shark scales under certain conditions in both cases. We hypothesize that the scales provide a passive, flow-actuated mechanism acting as a dynamic micro-roughness to control flow separation.

  18. Comparative study of enzymatic antioxidants in muscle of elasmobranch and teleost fishes.

    PubMed

    Vélez-Alavez, Marcela; De Anda-Montañez, Juan A; Galván-Magaña, Felipe; Zenteno-Savín, Tania

    2015-09-01

    Exercise may cause an imbalance between pro-oxidants and antioxidants. In skeletal muscle, oxygen flow can increase considerably during vigorous exercise. The antioxidant system in athletes contributes to neutralize the concomitant rise in reactive oxygen species (ROS) production. The objective of this study was to compare the antioxidant system in muscle of three species of elasmobranchs and teleosts, considering differences in swimming capacity among species within each group and evolutionary differences between the two groups. Muscle samples were collected from elasmobranchs (Isurus oxyrinchus, Prionace glauca, Mustelus henlei) and teleosts (Totoaba macdonaldi, Kajikia audax and Coryphaena hippurus) in the coast of the Baja California peninsula, Mexico. The enzymatic activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione S-transferase (GST) was determined by spectrophotometry. The activity of the antioxidant enzymes CAT, GPx and GST was higher in elasmobranchs, as a group, than in teleosts. In fish species with high swimming capacities, P. glauca, K. audax and C. hippurus, antioxidant enzyme activity was higher in comparison with species with lower swimming capacities, M. henlei and T. macdonaldi. It is possible that antioxidant enzymes, particularly SOD, GPx and GST, contribute to avoidance of oxidative damage in teleost and elasmobranch species with higher swimming capacities. The antioxidant enzyme activities in fish appear to depend mainly on their swimming capacity and life style rather than the evolutionary group (elasmobranchs, teleosts).

  19. An Experimental Study of Flow Separation Control by Shortfin Mako Shark Skin

    NASA Astrophysics Data System (ADS)

    Afroz, Farhana; Lang, Amy; Motta, Philip; Habegger, Maria

    2013-11-01

    The shortfin mako shark (Isurus oxyrinchus) is a fast swimmer and has incredible turning agility. Shark skin is covered with flexible scales and this bristling capability may result in a unique Boundary Layer Control (BLC) method to reduce drag. It is hypothesized that scales bristle when the flow above it is reversed, and between the bristled scales embedded micro-vortices form in the cavities which induce boundary layer mixing and aid in delaying flow separation. To testify this hypothesis, samples of mako shark skin have been tested in a water tunnel under various strengths of adverse pressure gradient (APG). Laminar and turbulent separation over shark skin was studied experimentally using Time-Resolved Digital Particle Image Velocimetry (TR-DPIV) system, where the APG was generated and varied using a rotating cylinder. Then shark skin results were compared with that of a flat plate data for a given amount of APG. The study reveals that shark skin is capable of controlling both laminar and turbulent flow separation. Support under NSF grant 0932352 is gratefully acknowledged. First author Farhana Afroz was also supported by a scholarship through the Alabama EPSCoR Graduate Research Scholars Program.

  20. Shark Skin Bristling: A Passive Flow-Actuated Separation Control Mechanism

    NASA Astrophysics Data System (ADS)

    Lang, Amy; Smith, Jonathon; Bradshaw, Michael; Wheelus, Jennifer; Motta, Philip; Habegger, Maria; Davis, Jessica; Hueter, Robert

    2012-11-01

    A collaborative experimental effort between biologists and engineers has proven the separation control capability of shark skin, with a specific focus on the shortfin mako (Isurus oxyrinchus) known for its high speed and agility. Biological measurements of the denticles, or scales, as a function of body location (DOI:10.1002/jmor.20047) will be presented together with data on bristling angle of scales and the morphological implications. Results show key regions of high bristling capability to correspond with those most prone to flow separation; these include the tail, flank regions aft of the gills, and on pectoral fins with scale flexibility increasing towards the trailing edge. Fresh shark skin samples were also tested in a water tunnel facility using DPIV and evidence of flow separation control was observed under laminar and tripped boundary layer conditions. It was concluded that the experiments conducted in the Re ~ 105 range resulted in sufficiently strong backflow induced close to the surface such that the shear threshold to induce bristling on the real skin sample was achieved since flow control at lower Re was not as evident. It is hypothesized that backflow initiated close to the wall in a region of adverse pressure gradient induces localized scale bristling thereby interrupting the subsequent flow development that leads to global flow separation from the surface and increased drag. Funding from NSF CBET grant 0932352 and US DOD AMRDEC.

  1. Recent Observations on Shortfin Mako Scale Flexibility as a Mechanism for Separation Control

    NASA Astrophysics Data System (ADS)

    Lang, Amy; Motta, Philip; Habegger, Maria; Jones, Emily; Hueter, Robert

    2010-11-01

    Recent results obtained from examining the skin of the shortfin mako (Isurus oxyrinchus) suggest that scale flexibility may provide a passive, flow actuated mechanism for controlling flow separation. The shortfin mako is considered to be one of the fastest and most agile marine predators. High contragility, or the ability to change direction while already in a turn, requires minimal form drag and thus control of flow separation on body regions aft of the point of maximum girth. Recent biological observations have found that the shortfin mako has highly flexible scales, or denticles, particularly on the sides of the body downstream of the gills; in these regions scale crowns can be easily manipulated to angles in excess of 60 degrees. Histological data of the skin provides preliminary evidence that this flexibility is achieved due, in part, to a reduction in the size of the base of the scale where it is anchored into the skin. Experimental measurements of maximum angle of denticle bristling observed as a function of body location will be presented and a probable mechanism leading to separation control will be discussed.

  2. A flow separation study over a shortfin mako shark pectoral fin

    NASA Astrophysics Data System (ADS)

    Bradshaw, Michael; Lang, Amy; Wahidi, Redha; Smith, Drew; Motta, Philip

    2011-11-01

    Many animals possess performance enhancing mechanisms, such as the denticles found on the skin of the shortfin mako shark (Isurus oxyrinchus). The shortfin mako, one of the fastest sharks on the planet, is covered by small, tooth-like scales that vary in bristling capability. Previous biological findings have shown that the scales increase in flexibility from the leading to trailing edge over the pectoral fin. As this fin is a primary control surface, the scale bristling may provide a mechanism for separation control that leads to decreased drag and increased maneuverability. Such findings can potentially lead to the development of similar micro-scale mechanisms to improve the efficiency of aerospace design. A left pectoral fin (71 cm span) was tested in a water tunnel facility under static and dynamic conditions. Digital Particle Image Velocimetry (DPIV) was used to characterize the flow over the fin. Various angles of attack at two speeds were tested (Re of 44,500 and 68,000). Two chord-wise locations, approximately mid-span where three-dimensional effects were minimized, were viewed to analyze the flow. After the initial testing, the fin was painted to eliminate the effect of the scales and retested to observe flow separation. Supported by REU SITE EEC grant number 1062611.

  3. Loss of large predatory sharks from the Mediterranean Sea.

    PubMed

    Ferretti, Francesco; Myers, Ransom A; Serena, Fabrizio; Lotze, Heike K

    2008-08-01

    Evidence for severe declines in large predatory fishes is increasing around the world. Because of its long history of intense fishing, the Mediterranean Sea offers a unique perspective on fish population declines over historical timescales. We used a diverse set of records dating back to the early 19th and mid 20th century to reconstruct long-term population trends of large predatory sharks in the northwestern Mediterranean Sea. We compiled 9 time series of abundance indices from commercial and recreational fishery landings, scientific surveys, and sighting records. Generalized linear models were used to extract instantaneous rates of change from each data set, and a meta-analysis was conducted to compare population trends. Only 5 of the 20 species we considered had sufficient records for analysis. Hammerhead (Sphyrna spp.), blue (Prionace glauca), mackerel (Isurus oxyrinchus and Lamna nasus), and thresher sharks (Alopias vulpinus) declined between 96 and 99.99% relative to their former abundance. According to World Conservation Union (IUCN) criteria, these species would be considered critically endangered. So far, the lack of quantitative population assessments has impeded shark conservation in the Mediterranean Sea. Our study fills this critical information gap, suggesting that current levels of exploitation put large sharks at risk of extinction in the Mediterranean Sea. Possible ecosystem effects of these losses involve a disruption of top-down control and a release of midlevel consumers.

  4. Capture of white sturgeon larvae downstream of The Dalles Dam, Columbia River, Oregon and Washington, 2012

    USGS Publications Warehouse

    Parsley, Michael J.; Kofoot, Eric

    2013-01-01

    Wild-spawned white sturgeon (Acipenser transmontanus) larvae captured and reared in aquaculture facilities and subsequently released, are increasingly being used in sturgeon restoration programs in the Columbia River Basin. A reconnaissance study was conducted to determine where to deploy nets to capture white sturgeon larvae downstream of a known white sturgeon spawning area. As a result of the study, 103 white sturgeon larvae and 5 newly hatched free-swimming embryos were captured at 3 of 5 reconnaissance netting sites. The netting, conducted downstream of The Dalles Dam on the Columbia River during June 25–29, 2012, provided information for potentially implementing full-scale collection efforts of large numbers of larvae for rearing in aquaculture facilities and for subsequent release at a larger size in white sturgeon restoration programs.

  5. Idaho Water Rental Pilot Project probability/coordination study resident fish and wildlife impacts, Phase III. Annual report

    SciTech Connect

    Leitzinger, E.

    1996-09-01

    Phase III began in 1995 with the overall goal of quantifying changes in resident fish habitat in the Snake River basin upstream of Brownlee Reservoir resulting from the release of salmon flow augmentation water. Existing data, in the form of weighted usable area versus flow relationships, were used to estimate habitat changes for white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss)in the Snake River between C.J. Strike Dam and Brownlee pool. The increased flows resulted in increased white sturgeon habitat for most life stages. Rainbow trout adult and spawning habitat increased while juvenile and fry habitat generally decreased. Whether or not these short term increases in habitat result in long term benefits to the fish populations has yet to be determined.

  6. Recovery of white sturgeon populations through natural production: Understanding the influence of abiotic and biotic factors on spawning and subsequent recruitment

    USGS Publications Warehouse

    Parsley, M.J.; Anders, P.J.; Miller, A.I.; Beckman, L.G.; McCabe, G.T.

    2002-01-01

    Recovery or maintenance of sturgeon populations through natural production in perturbed rivers requires adequate knowledge of the abiotic and biotic factors that influence spawning and cause mortality of embryonic, larval, and juvenile life stages. Although it is known that year-class strength of white sturgeon Acipenser transmontanus is determined within 2-3 months after spawning, little is known about specific causes of mortality to early life stages during this period. Initial spawning success is critical in the development of a strong year-class, and maximized recruitment may be dependent upon water temperature and the availability of optimal in-river habitat. Analyses have shown that increased river discharge combined with suitable water temperatures during spawning, egg incubation, yolk sac larvae dispersal, and first exogenous feeding result in greater recruitment. However, little is known about the importance of other variables, such as food availability or losses due to predation that influence year-class strength. ?? 2002 by the American Fisheries Society.

  7. White sturgeon spawning and rearing habitat in the lower Columbia River

    USGS Publications Warehouse

    Parsley, Michael J.; Beckman, Lance G.

    1994-01-01

    Estimates of spawning habitat for white sturgeons Acipenser transmontanus in the tailraces of the four dams on the lower 470 km of the Columbia River were obtained by using the Physical Habitat Simulation System of the U.S. Fish and Wildlife Service's Instream Flow Incremental Methodology to identify areas with suitable water depths, water velocities, and substrates. Rearing habitat throughout the lower Columbia River was assessed by using a geographic information system to identify areas with suitable water depths and substrates. The lowering of spring and summer river discharges from hydropower system operation reduces the availability of spawning habitat for white sturgeons. The four dam tailraces in the study area differ in the amount and quality of spawning habitat available at various discharges; the differences are due to channel morphology. The three impoundments and the free-flowing Columbia River downstream from Bonneville Dam provide extensive areas that are physically suitable for rearing young-of-the-year and juvenile white sturgeons.

  8. White sturgeon spawning areas in the lower Snake River

    USGS Publications Warehouse

    Parsley, M.J.; Kappenman, K.M.

    2000-01-01

    We documented 17 white sturgeon Acipenser transmontanus spawning locations in the Snake River from the mouth to Lower Granite Dam (river km 0 to 173). Spawning locations were determined by the collection of fertilized eggs on artificial substrates or in plankton nets. We collected 245 eggs at seven locations in McNary Reservoir, 22 eggs at three locations in Ice Harbor Reservoir, 30 eggs from two locations in Lower Monumental Reservoir, and 464 eggs at five locations in Little Goose Reservoir. All 17 locations were in high water velocity areas and between 1.0 and 7.0 km downstream from a hydroelectric dam. The documentation of spawning areas is important because this habitat is necessary to maintain natural and viable populations.

  9. Idaho Water Rental Pilot Project Probability/Coordination Study Resident Fish and Wildlife Impact Phase III, 1995 Annual Report.

    SciTech Connect

    Leitzinger, Eric J.

    1996-09-01

    Phase III began in 1995 with the overall goal of quantifying changes in resident fish habitat in the Snake River basin upstream of Brownlee Reservoir resulting from the release of salmon flow augmentation water. Existing data, in the form of weighted usable area versus flow relationships, were used to estimate habitat changes for white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) in the Snake River between C.J. Strike Dam and Brownlee pool. The increased flows resulted in increased white sturgeon habitat for most life stages. Rainbow trout adult and spawning habitat increased while juvenile and fry habitat generally decreased. Whether or not these short term increases in habitat result in long term benefits to the fish populations has yet to be determined.

  10. Influence of a low intensity electric sea lion deterrence system on the migratory behavior of fishes in the upstream migrant tunnel (UMT) at Bonneville Dam.

    USGS Publications Warehouse

    Mesa, Matthew G.; Dixon, Christopher J.

    2010-01-01

    salmonids. As a result, Smith-Root Incorporated (SRI; Vancouver, Washington) proposed a demonstration project to evaluate the potential of an electrical array to deter marine mammals (SRI 2007). The objective of their work was to develop, deploy, and evaluate a passive, integrated electric and sonar array that selectively inhibits upstream marine mammal movements and predation, without injuring pinnipeds or affecting anadromous fish migrations. However, before such a device could be placed in the field, concerns by regional fishery managers about the potential effects of such a device on the migratory behavior of or injury to Pacific salmon, steelhead (O. mykiss), Pacific lampreys (Entoshpenus tridentata), and white sturgeon (Acipenser transmontanus) needed to be addressed.

  11. Feeding behaviour of Black Sea bottom fishes: Did it change over time?

    NASA Astrophysics Data System (ADS)

    Bănaru, Daniela; Harmelin-Vivien, Mireille

    2009-11-01

    This study was designed to improve knowledge in feeding behaviour of the round goby ( Apollonia melanostomus (Pallas, 1814)), the red mullet ( Mullus barbatus ponticus Essipov, 1927), the whiting ( Merlangius merlangus (Linnaeus, 1758)), the flounder ( Platichthys flesus (Linnaeus, 1758)), the sole ( Solea solea (Linnaeus, 1758)), the turbot ( Psetta maeotica (Pallas, 1814)) and the starry sturgeon ( Acipenser stellatus Pallas, 1771) from the north-western Black Sea. Gut content coupled with stable isotope analysis allowed describing food web variations according to species, in two seasons and at two areas located seawards the Danube River. Present results showed that most fishes have likely changed their feeding behaviour compared to past studies from the same area. Trophic niches were reduced and dietary overlap was common, as different fish species consumed the same dominant prey types. Fishes probably adapted their feeding behaviour to the increasingly low biodiversity of the Black Sea communities.

  12. Individual variation in life history characteristics can influence extinction risk (vol 144, pg 61, 2001) Correction

    SciTech Connect

    Jager, Yetta

    2009-01-01

    The white sturgeon (Acipenser transmontanus) shows great individual variation in the age at maturation. This study examines the consequences of model assumptions about individual variation in the age at maturation on predicted population viability. I considered: (1) the effects of variation in age at maturation alone; (2) the effects of heritability; and (3) the influence of a stable and an altered selective regime. Two selective regimes represented conditions before and after the impoundment of a river, blocking access of anadromous white sturgeon populations to the ocean. In contrast to previous simulation studies, I found that increased individual variation in the age at maturity did not necessarily lead to a higher likelihood of persistence. Individual variation increased the simulated likelihood of persistence when the variation was heritable and the selective regime had changed such that the mean age at maturity was no longer optimal.

  13. Individual Variation in Life History Characteristics Can Influence Extinction Risk

    SciTech Connect

    Jager, H I

    2001-01-01

    The white sturgeon (Acipenser transmontanus) shows great individual variation in the age at maturation. This study examines the consequences of model assumptions about individual variation in the age at maturation on predicted population viability. I considered: (1) the effects of variation in age at maturation alone; (2) the effects of heritability; and (3) the influence of a stable and an altered selective regime. Two selective regimes represented conditions before and after the impoundment of a river, blocking access of anadromous white sturgeon populations to the ocean. In contrast to previous simulation studies, I found that increased individual variation in the age at maturity did not necessarily lead to a higher likelihood of persistence. Individual variation increased the simulated likelihood of persistence when the variation was heritable and the selective regime had changed such that the mean age at maturity was no longer optimal.

  14. The Effect on the Flow Conditions of Chinese Sturgeons’ Spawning Sites in the Process of Peak Regulation between the Three Gorges Dam and Gezhou Dam

    NASA Astrophysics Data System (ADS)

    Hui, Guo; Minghai, Huang; Feng, Jin

    Chinese sturgeon (Acipenser sinensis Gray) is a kind of key protected fish in ChangJiang river. Recently the Three Gorges dam has run, the peak regulation process between the two dams has serious effect on the formed spawning sites. Based on the previous research results of suitable flow conditions about the spawning sites, this article builds a 2-D shallow water numerical model, calculates the flow conditions of the spawning sites in the process of peak regulation. The results show that the water depth and velocity are various and affect the spawning sites in one 24-hours process of peak regulation, as a whole, when the discharge is below 9000 m3/s and 7500 m3/s respectively, the two spawning sites will be affected seriously.

  15. Radionuclide concentrations in white sturgeon from the Columbia River

    SciTech Connect

    Dauble, D.D.; Price, K.R.; Poston, T.M.

    1992-09-01

    Although radioactive releases from the US Department of Energy`s Hanford Site have been monitored in the environment since the reactors began operating in 1945, recent information regarding historical releases of radionuclides has led to renewed interest in estimating human exposure to radionuclides at Hanford. Knowledge of the fate of radionuclides in some fish species may be important because of the potential for food-chain transfer to humans. White sturgeon (Acipenser transmontanus) were selected for study because they are long-lived, reside year-round in the Hanford Reach, are benthic, and are an important commercial and sport species in the Columbia River. They also have a greater potential for accumulating persistent radionuclides than shorter-lived species with pelagic and/or anadromous life histories. The purpose of our study was to summarize data on historical concentrations of industrial radionuclides in white sturgeon and to collect additional data on current body burdens in the Columbia River.

  16. Radionuclide concentrations in white sturgeon from the Columbia River

    SciTech Connect

    Dauble, D.D.; Price, K.R.; Poston, T.M.

    1992-09-01

    Although radioactive releases from the US Department of Energy's Hanford Site have been monitored in the environment since the reactors began operating in 1945, recent information regarding historical releases of radionuclides has led to renewed interest in estimating human exposure to radionuclides at Hanford. Knowledge of the fate of radionuclides in some fish species may be important because of the potential for food-chain transfer to humans. White sturgeon (Acipenser transmontanus) were selected for study because they are long-lived, reside year-round in the Hanford Reach, are benthic, and are an important commercial and sport species in the Columbia River. They also have a greater potential for accumulating persistent radionuclides than shorter-lived species with pelagic and/or anadromous life histories. The purpose of our study was to summarize data on historical concentrations of industrial radionuclides in white sturgeon and to collect additional data on current body burdens in the Columbia River.

  17. Acute toxicity of ammonia and nitrite to shortnose sturgeon fingerlings

    USGS Publications Warehouse

    Fontenot, Q.C.; Isely, J.J.; Tomasso, J.R.

    1998-01-01

    The 96-h median-lethal concentration (96-h LC50) of total ammonia nitrogen (ammonia-N) to fingerling shortnose sturgeon Acipenser brevirostrum was 149.8 ?? 55.20 mg/L (mean ?? SD, 17.9 ?? 0.62??C, pH = 6.8-7.3). Calculated 96-h LC50 for un-ionized ammonia-N was 0.58 ?? 0.213 mg/L. The 96-h LC50 of nitrite nitrogen to shortnose sturgeon fingerlings was 11.3 ?? 8.17 mg/L (17.9 ?? 0.31??C, <1.0 mg chloride/L, <1.0 mg magnesium/L, 1.8 mg calcium/L, 7.7 mg sodium/L).

  18. Polypodium sp. (Coelenterata) infection of paddlefish (Polyodon spathula) eggs

    USGS Publications Warehouse

    Suppes, V. Charles; Meyer, Fred P.

    1975-01-01

    Parasitism of fish by coelenterates is rare and the first North American infection was reported in sturgeon (Hoffman et al., 1974, J Parasitol 60: 548-550). In the USSR parasitism of sturgeon (Acipenser sp.) eggs by the coelenterate Polypodium hydriforme Ussov 1885 has long been reported and investigated [Raikova, 1959, in Parasites of Freshwater Fish and the Biological Basis for their Control. Bull State Sci Res Inst Lake and River Fish. XLIX. Eng. transl. No. TT61-31056, O. T. S., U. S. Dep. Commerce, Washington, D. C., 1962, 235 p.: Raikova, 1973, (Proc Second Internat Symp on Cnidaria), Seto Marine Biological Laboratory 20: 165-173]. This report represents the first known infection of Polypodium in the paddlefish (Polyodon spathula).

  19. Detections of Acoustic-Tagged Green Sturgeon in Baker Bay on the Lower Columbia River during September - November 2008

    USGS Publications Warehouse

    Parsley, Michael J.

    2009-01-01

    Acoustic transmitters implanted in green sturgeon (Acipenser medirostris) captured in rivers in California were detected by acoustic receivers deployed within and around Baker Bay. The receivers were deployed at eight locations in the Bay and adjacent navigation channels of the Lower Columbia River during a period of anticipated channel dredging. Three of the transmitters detected were confirmed to have been implanted into green sturgeon in previous years; two were from the Sacramento River and one was from the Klamath River. The transmitters (fish) were within detection range of the receivers for only a short period, which is consistent with findings of earlier studies that green sturgeon make rapid and extensive intra-estuary movements.

  20. Kootenai River White Sturgeon Conservation Aquaculture Project : Environmental Assessment.

    SciTech Connect

    US Bonneville Power Administration; Kootenai Tribe of Idaho

    1997-04-01

    Bonneville Power Administration (BPA) is responding to the need to prevent the extinction of the Kootenai River white sturgeon (Acipenser transmontanus) between Libby Dam in Montana and Corra Linn Dam in British Columbia. Construction and operation of Libby Dam altered the natural flow of the Kootenai River, especially the normal May-to-July flows needed for natural reproduction and recruitment. It also affected the river`s biological productivity and the quality of spawning and rearing habitat. As part of its responsibilities under the Northwest Power Act (Pacific Northwest Electric Power Planning and Conservation Act of 1980), BPA must mitigate for losses of fish and wildlife (including related spawning grounds and habitat) that are attributable to power production at federal hydroelectric dams on the Columbia River and its tributaries.

  1. Use of electronarcosis to immobilize juvenile lake and shortnose sturgeons for handling and the effects on their behavior

    USGS Publications Warehouse

    Henyey, E.; Kynard, B.; Zhuang, P.

    2002-01-01

    Low voltage constant direct current was used to immobilize juvenile lake (Acipenser fulvescens) and shortnose sturgeons (A. brevirostrum). There was no significant difference in time/ the lake or shortnose sturgeons required to exhibit positive rheotaxis between fish immobilized with electricity and control fish (two-way ANOVA, P = 0.11). Fish immobilized with 80 mg L-1 tricaine took a significantly longer time to orient than control fish or fish immobilized with electricity for 5 or 30 min (one-way ANOVA, P = 0.003). Electronarcosis, which produces effects like a chemical anesthetic, is a useful technique for immobilizing juvenile sturgeons for handling. Fish can swim upright as soon as the electricity is turned off, recovery time is shorter than with chemical anesthetics, and the cost of equipment is < 400 USD.

  2. Evaluation of shortnose sturgeon spawning in the Pinopolis Dam tailrace, South Carolina

    USGS Publications Warehouse

    Duncan, M.S.; Isely, J.J.; Cooke, D.W.

    2004-01-01

    Fifty egg mats and up to five D-shaped plankton nets were deployed in the tailrace of Pinopolis Dam at river kilometer 77 on the Cooper River, South Carolina, to evaluate the spawning activity of shortnose sturgeon Acipenser brevirostrum. Spawning times were estimated by back-calculation based on developmental phase. Eggs were collected on 17 of 21 d sampled continuously from March 4 through March 25, 2002, when water temperatures were 10-16??C. A total of 31 shortnose sturgeon eggs were collected from egg mats. An additional 338 shortnose sturgeon eggs and 1 newly hatched yolk sac larva were collected from plankton nets. A minimum of 20 spawning events occurred in the tailrace during the 2002 spawning season. No relationship between mean daily discharge and spawning date was observed. Shortnose sturgeon spawned more often during the night than at any other time of day independent of generation.

  3. Persistence of identifiable remains of white sturgeon juveniles in digestive tracts of northern pikeminnow

    USGS Publications Warehouse

    Gadomski, D.M.; Frost, C.N.

    2004-01-01

    Juvenile white sturgeon, Acipenser transmontanus, have not been commonly identified as prey items in digestive tracts of fishes collected in the wild. In particular, the diet of northern pikeminnow, Ptychocheilus oregonensis, an abundant Pacific Northwest freshwater predator which has been widely studied, has not included juvenile white sturgeon. To aid in interpreting these results and help in planning future feeding studies, we determined the persistence of identifiable remains of white sturgeon juveniles in this predator's digestive tract. Northern pikeminnow (mean total length = 476 mm), were force-fed meals of 2 or 3 juvenile white sturgeon (mean total length = 91 mm). After digestive periods of 4, 8, 16, 24, 28, and 32h at a water temperature of about 17 ??C, fish were sacrificed, digestive tracts removed, and contents examined. Our results indicate that juvenile white sturgeon would be readily discernable in digestive tracts of northern pikeminnow at least a day after feeding, with scutes remaining undigested and identifiable for 28 h.

  4. Polycystic lesions in the liver of the white sturgeon.

    PubMed

    Taylor, Peter; Smith, Charlie E; Blair, Marilyn J

    2009-03-01

    Polycystic lesions have been reported from the kidney and liver of many different fish species and are attributed to pollution and genetic anomalies. In June 2002, eggs and milt were collected from two female and five male white sturgeon Acipenser transmontanus below Bonneville Dam on the Columbia River. Fertilized eggs were hatched at the Abernathy Fish Technology Center in Longview, Washington, and 20,000 juveniles were raised for approximately 1 year before release into the wild. Just before release, 12,000 juveniles were scute-marked, during which it was noticed that about 30 fish had distended abdomens. Gross necropsy revealed a large, jellylike mass in the peritoneal cavity. Histopathological examination of four fish showed that this growth was a polycystic lesion of liver tissue. This is the first report of this type of lesion in white sturgeon and is presumed to be the product of a genetic anomaly.

  5. Concentrations of elements in fish fillets, fish muscle plugs, and crayfish from the 2007 Missouri Department of Conservation General Contaminant Monitoring Program

    USGS Publications Warehouse

    May, Thomas W.; Walther, Michael J.; Brumbaugh, William G.; McKee, Michael J.

    2009-01-01

    This report presents the results of a contaminant monitoring survey conducted annually by the Missouri Department of Conservation to examine the levels of selected elemental contaminants in fish fillets, fish muscle plugs, and crayfish. Fillets of channel catfish (Ictalurus punctatus), bass (Micropterus salmoides, Micropterus dolomieu, Morone chrysops), walleye (Sander vitreus), common carp (Cyprinus carpio), lake sturgeon (Acipenser fulvescens), northern hog sucker (Hypentelium nigricans), and rainbow trout (Oncorhynchus mykiss) were collected from 21 sites as part of the Department's Fish Contaminant Monitoring Program. Long-pincered crayfish (Orconectes longidigitus) were collected from one site to assess trophic transfer of metals to fish. Fish muscle plugs were collected from smallmouth bass (Micropterus dolomieu) at two different locations from one site.

  6. Review: the Caspian Sea benthos: unique fauna and community formed under strong grazing pressure.

    PubMed

    Karpinsky, M G

    2010-01-01

    A quantitative comparison of the benthic distribution in the Middle and Southern Caspian Sea, using benthos distribution maps with previously published materials, showed that the benthic communities is stable and interrupted only by the introduction of new species. The bottom community is dominated by small-size organisms, mainly fry and young and the benthic biomass is low although its efficiency as prey for higher trophic levels is high even though carnivores are almost absent in the bottom community. At depths of c.100 m the benthos biomass and species diversity sharply decreases showing these features as a unique case of a bottom fauna and bottom community formed and modified under the influence of a severe grazing pressure by the sturgeon (Acipenser spp.) during very long periods. It is therefore suggested that grazing pressure has become the most important forcing function for the diversity and development of the bottom community.

  7. Adaption of egg and larvae sampling techniques for lake sturgeon and broadcast spawning fishes in a deep river

    USGS Publications Warehouse

    Roseman, Edward F.; Kennedy, Gregory W.; Craig, Jaquelyn; Boase, James; Soper, Karen

    2011-01-01

    In this report we describe how we adapted two techniques for sampling lake sturgeon (Acipenser fulvescens) and other fish early life history stages to meet our research needs in the Detroit River, a deep, flowing Great Lakes connecting channel. First, we developed a buoy-less method for sampling fish eggs and spawning activity using egg mats deployed on the river bottom. The buoy-less method allowed us to fish gear in areas frequented by boaters and recreational anglers, thus eliminating surface obstructions that interfered with recreational and boating activities. The buoy-less method also reduced gear loss due to drift when masses of floating aquatic vegetation would accumulate on buoys and lines, increasing the drag on the gear and pulling it downstream. Second, we adapted a D-frame drift net system formerly employed in shallow streams to assess larval lake sturgeon dispersal for use in the deeper (>8 m) Detroit River using an anchor and buoy system.

  8. Influence of externally attached transmitters on the swimming performance of juvenile white sturgeon

    USGS Publications Warehouse

    Counihan, T.D.; Frost, C.N.

    1999-01-01

    We measured the critical swimming speed of juvenile white sturgeons Acipenser transmontanus equipped with externally attached dummy ultrasonic transmitters and of untagged control fish in the laboratory. White sturgeons ranging from 31.9 to 37.0 cm fork length were subjected to one of three treatments: control (handled but not tagged), tag attached below the dorsal fin, and tag attached with the anterior insertion point between the fourth and fifth dorsal scutes. Although transmitters were of recommended weight, we found that the swimming performance of tagged white sturgeons was significantly less than that of untagged control fish. Swimming performance of tagged fish was not differentially affected by tag location. Our results suggest that data from ultrasonic telemetry studies of externally tagged juvenile white sturgeons should be interpreted with caution due to the reduced swimming performance caused by external transmitters.

  9. Influence of externally attached trasmitters on the swimming performance of juvenile white sturgeon

    USGS Publications Warehouse

    Counihan, T.D.; Frost, C.N.

    1999-01-01

    We measured the critical swimming speed of juvenile white sturgeons Acipenser transmontanus equipped with externally attached dummy ultrasonic transmitters and of untagged control fish in the laboratory. White sturgeons ranging from 31.9 to 37.0 cm fork length were subjected to one of three treatments: Control (handled but not tagged), tag attached below the dorsal fin, and tag attached with the anterior insertion point between the fourth and fifth dorsal scutes. Although transmitters were of recommended weight, we found that the swimming performance of tagged white sturgeons was significantly less than that of untagged control fish. Swimming performance of tagged fish was not differentially affected by tag location. Our results suggest that data from ultrasonic telemetry studies of externally tagged juvenile white sturgeons should be interpreted with caution due to the reduced swimming performance caused by external transmitters.

  10. Tana1, a new putatively active Tc1-like transposable element in the genome of sturgeons.

    PubMed

    Pujolar, José Martin; Astolfi, Laura; Boscari, Elisa; Vidotto, Michele; Barbisan, Federica; Bruson, Alice; Congiu, Leonardo

    2013-01-01

    We report the discovery of a new putatively active Tc1-like transposable element (Tana1) in the genome of sturgeons, an ancient group of fish considered as living fossils. The complete sequence of Tana1 was first characterized in the 454-sequenced transcriptome of the Adriatic sturgeon (Acipenser naccarii) and then isolated from the genome of the same species and from 12 additional sturgeons including three genera of the Acipenseridae (Acipenser, Huso, Scaphirhynchus). The element has a total length of 1588bp and presents inverted repeats of 210bp, one of which partially overlapping the 3' region of the transposase gene. The spacing of the DDE motif within the catalytic domain in Tana1 is unique (DD38E) and indicates that Tana1 can be considered as the first representative of a new Tc1 subfamily. The integrity of the native form (with no premature termination codons within the transposase), the presence of all expected functional domains and its occurrence in the sturgeon transcriptome suggest a current or recent activity of Tana1. The presence of Tana1 in the genome of the 13 sturgeon species in our study points to an ancient origin of the element that existed before the split of the group 170 million years ago. The dissemination of Tana1 across sturgeon genomes could be interpreted by postulating vertical transmission from an ancestral Tana1 with a particularly slow evolutionary rate Horizontal transmission might have also played a role in the dissemination of Tana1 as evidenced by the presence of a complete copy in the genome of Atlantic salmon. Vertical and horizontal transmission are not mutually exclusive and may have concurred in shaping the evolution of Tana1.

  11. Larval green and white sturgeon swimming performance in relation to water-diversion flows.

    PubMed

    Verhille, Christine E; Poletto, Jamilynn B; Cocherell, Dennis E; DeCourten, Bethany; Baird, Sarah; Cech, Joseph J; Fangue, Nann A

    2014-01-01

    Little is known of the swimming capacities of larval sturgeons, despite global population declines in many species due in part to fragmentation of their spawning and rearing habitats by man-made water-diversion structures. Larval green (Acipenser medirostris) and white sturgeon (Acipenser transmontanus) inhabit the highly altered Sacramento-San Joaquin watershed, making them logical species to examine vulnerability to entrainment by altered water flows. The risk of larval sturgeon entrainment is influenced by the ontogeny of swimming capacity and dispersal timing and their interactions with water-diversion structure operations. Therefore, the aim of this study was to describe and compare the ontogeny and allometry of larval green and white sturgeon swimming capacities until completion of metamorphosis into juveniles. Despite the faster growth rates and eventual larger size of larval white sturgeon, green sturgeon critical swimming velocities remained consistently, though modestly, greater than those of white sturgeon throughout the larval life stage. Although behavioural interactions with water-diversion structures are also important considerations, regarding swimming capacity, Sacramento-San Joaquin sturgeons are most vulnerable to entrainment in February-May, when white sturgeon early larvae are in the middle Sacramento River, and April-May, when green sturgeon early larvae are in the upper river. Green sturgeon migrating downstream to the estuary and bays in October-November are also susceptible to entrainment due to their movements combined with seasonal declines in their swimming capacity. An additional inter-species comparison of the allometric relationship between critical swimming velocities and total length with several sturgeon species found throughout the world suggests a similar ontogeny of swimming capacity with growth. Therefore, although dispersal and behaviour differ among river systems and sturgeon species, similar recommendations are applicable

  12. Use of multidimensional modeling to evaluate a channel restoration design for the Kootenai River, Idaho

    USGS Publications Warehouse

    Logan, B.L.; McDonald, R.R.; Nelson, J.M.; Kinzel, P.J.; Barton, G.J.

    2011-01-01

    River channel construction projects aimed at restoring or improving degraded waterways have become common but have been variously successful. In this report a methodology is proposed to evaluate channel designs before channels are built by using multidimensional modeling and analysis. This approach allows detailed analysis of water-surface profiles, sediment transport, and aquatic habitat that may result if the design is implemented. The method presented here addresses the need to model a range of potential stream-discharge and channel-roughness conditions to best assess the function of the design channel for a suite of possible conditions. This methodology is demonstrated by using a preliminary channel-restoration design proposed for a part of the Kootenai River in northern Idaho designated as critical habitat for the endangered white sturgeon (Acipenser transmontanus) and evaluating the design on the basis of simulations with the Flow and Sediment Transport with Morphologic Evolution of Channels (FaSTMECH) model. This evaluation indicated substantial problems with the preliminary design because boundary conditions used in the design were inconsistent with best estimates of future conditions. As a result, simulated water-surface levels did not meet target levels that corresponded to the designed bankfull surfaces; therefore, the flood plain would not function as intended. Sediment-transport analyses indicated that both the current channel of the Kootenai River and the design channel are largely unable to move the bed material through the reach at bankfull discharge. Therefore, sediment delivered to the design channel would likely be deposited within the reach instead of passing through it as planned. Consequently, the design channel geometry would adjust through time. Despite these issues, the design channel would provide more aquatic habitat suitable for spawning white sturgeon (Acipenser transmontanus) at lower discharges than is currently available in the

  13. Homology of lungs and gas bladders: insights from arterial vasculature.

    PubMed

    Longo, Sarah; Riccio, Mark; McCune, Amy R

    2013-06-01

    Gas bladders of ray-finned fishes serve a variety of vital functions and are thus an important novelty of most living vertebrates. The gas bladder has long been regarded as an evolutionary modification of lungs. Critical evidence for this hypothesized homology is whether pulmonary arteries supply the gas bladder as well as the lungs. Pulmonary arteries, paired branches of the fourth efferent branchial arteries, deliver blood to the lungs in osteichthyans with functional lungs (lungfishes, tetrapods, and the ray-finned polypterid fishes). The fact that pulmonary arteries also supply the respiratory gas bladder of Amia calva (bowfin) has been used to support the homology of lungs and gas bladders, collectively termed air-filled organs (AO). However, the homology of pulmonary arteries in bowfin and lunged osteichthyans has been uncertain, given the apparent lack of pulmonary arteries in critical taxa. To re-evaluate the homology of pulmonary arteries in bowfin and lunged osteichthyans, we studied, using micro-CT technology, the arterial vasculature of Protopterus, Polypterus, Acipenser, Polyodon, Amia, and Lepisosteus, and analyzed these data using a phylogenetic approach. Our data reveal that Acipenser and Polyodon have paired posterior branches of the fourth efferent branchial arteries, which are thus similar in origin to pulmonary arteries. We hypothesize that these arteries are vestigial pulmonary arteries that have been coopted for new functions due to the dorsal shift of the AO and/or the loss of respiration in these taxa. Ancestral state reconstructions support pulmonary arteries as a synapomorphy of the Osteichthyes, provide the first concrete evidence for the retention of pulmonary arteries in Amia, and support thehomology of lungs and gas bladders due to a shared vascular supply. Finally, we use ancestral state reconstructions to show that arterial AO supplies from the celiacomesenteric artery or dorsal aorta appear to be convergent between teleosts and

  14. Distribution and composition pattern of polycyclic aromatic hydrocarbons in different tissues of sturgeons collected from Iranian coastline of the Caspian Sea.

    PubMed

    Mashroofeh, Abdulreza; Bakhtiari, Alireza Riyahi; Pourkazemi, Mohammad

    2015-02-01

    The levels of 16 polycyclic aromatic hydrocarbons (PAHs) were determined in the liver, kidney, gills and muscle tissues of Persian sturgeon (Acipenser persicus; n=16), and Stellate sturgeon (Acipenser stellatus; n=7) collected from coastal waters of the South Caspian Sea from March and April 2011. The distribution and composition pattern of PAHs in the different tissues of sturgeons, and the effects of lipid content in sturgeon tissues and the octanol-water partition coefficient (Kow) of PAHs congeners on them were analyzed. The levels of total PAHs in the various tissues of Persian sturgeon and Stellate sturgeon ranged from 2.095 to 6.587 and 1.942 to 6.206 μg g(-1)dw, respectively. Stellate sturgeon showed significantly higher levels of heavy PAHs (⩾ 4-rings) than Persian sturgeon. The analysis has revealed a high degree of differential accumulation of the studied PAHs in the tissues of the both species. Low molecular weight PAHs predominated in the sturgeons, accounting for 81.89% of the total PAHs. Among the sixteen tested PAHs, naphthalene was the most dominant congener, followed by phenanthrene and fluorene. The PAHs levels and distribution in the tissues of sturgeons are dependent on both the Kow of PAH congeners and the lipid content in these tissues. There was a significant positive relationship (r=0.868, p<0.005) between lipid content and PAHs levels. The statistically significant negative relationships (p<0.01) were found between log Kow and log-transformed PAHs levels for muscle tissues of both sturgeon species.

  15. Differences in activation of aryl hydrocarbon receptors of white sturgeon relative to lake sturgeon are predicted by identities of key amino acids in the ligand binding domain.

    PubMed

    Doering, Jon A; Farmahin, Reza; Wiseman, Steve; Beitel, Shawn C; Kennedy, Sean W; Giesy, John P; Hecker, Markus

    2015-04-07

    Dioxin-like compounds (DLCs) are pollutants of global environmental concern. DLCs elicit their adverse outcomes through activation of the aryl hydrocarbon receptor (AhR). However, there is limited understanding of the mechanisms that result in differences in sensitivity to DLCs among different species of fishes. Understanding these mechanisms is critical for protection of the diversity of fishes exposed to DLCs, including endangered species. This study investigated specific mechanisms that drive responses of two endangered fishes, white sturgeon (Acipenser transmontanus) and lake sturgeon (Acipenser fulvescens) to DLCs. It determined whether differences in sensitivity to activation of AhRs (AhR1 and AhR2) can be predicted based on identities of key amino acids in the ligand binding domain (LBD). White sturgeon were 3- to 30-fold more sensitive than lake sturgeon to exposure to 5 different DLCs based on activation of AhR2. There were no differences in sensitivity between white sturgeon and lake sturgeon based on activation of AhR1. Adverse outcomes as a result of exposure to DLCs have been shown to be mediated through activation of AhR2, but not AhR1, in all fishes studied to date. This indicates that white sturgeon are likely to have greater sensitivity in vivo relative to lake sturgeon. Homology modeling and in silico mutagenesis suggests that differences in sensitivity to activation of AhR2 result from differences in key amino acids at position 388 in the LBD of AhR2 of white sturgeon (Ala-388) and lake sturgeon (Thr-388). This indicates that identities of key amino acids in the LBD of AhR2 could be predictive of both in vitro activation by DLCs and in vivo sensitivity to DLCs in these, and potentially other, fishes.

  16. Effect of dietary selenomethionine on growth performance, tissue burden, and histopathology in green and white sturgeon.

    PubMed

    De Riu, Nicola; Lee, Jang-Won; Huang, Susie S Y; Moniello, Giuseppe; Hung, Silas S O

    2014-03-01

    A comparative examination of potential differences in selenium (Se) sensitivity was conducted on two sturgeon species indigenous to the San Francisco Bay-Delta. Juvenile green (Acipenser medirostris), recently given a federally threatened status, and white sturgeon (Acipenser transmontanus) were exposed to one of four nominal concentrations of dietary l-selenomethionine (SeMet) (0 (control), 50, 100, or 200 mg SeMet/kg diet) for 8 weeks. Mortality, growth performance, whole body composition, histopathology, and Se burdens of the whole body, liver, kidneys, gills, heart, and white muscle were determined every 2 to 4 weeks. Significant (p<0.05) mortality was observed in green sturgeon fed the highest SeMet diet after 2 weeks, whereas no mortality was observed in white sturgeon. Growth rates were significantly reduced in both species; however, green sturgeon was more adversely affected by the treatment. Dietary SeMet significantly affected whole body composition and most noticeably, in the decline of lipid contents in green sturgeon. Selenium accumulated significantly in all tissues relative to the control groups. After 4 and 8 weeks of exposure, marked abnormalities were observed in the kidneys and liver of both sturgeon species; however, green sturgeon was more susceptible to SeMet than white sturgeon at all dietary SeMet levels. Our results showed that a dietary Se concentration at 19.7 ± 0.6 mg Se/kg, which is in range with the reported Se concentrations of the benthic macro-vertebrate community of the San Francisco Bay, had adverse effects on both sturgeon species. However, the exposure had a more severe pathological effect on green sturgeon, suggesting that when implementing conservation measures, this federally listed threatened species should be monitored and managed independently from white sturgeon.

  17. Larval green and white sturgeon swimming performance in relation to water-diversion flows

    PubMed Central

    Verhille, Christine E.; Poletto, Jamilynn B.; Cocherell, Dennis E.; DeCourten, Bethany; Baird, Sarah; Cech, Joseph J.; Fangue, Nann A.

    2014-01-01

    Little is known of the swimming capacities of larval sturgeons, despite global population declines in many species due in part to fragmentation of their spawning and rearing habitats by man-made water-diversion structures. Larval green (Acipenser medirostris) and white sturgeon (Acipenser transmontanus) inhabit the highly altered Sacramento–San Joaquin watershed, making them logical species to examine vulnerability to entrainment by altered water flows. The risk of larval sturgeon entrainment is influenced by the ontogeny of swimming capacity and dispersal timing and their interactions with water-diversion structure operations. Therefore, the aim of this study was to describe and compare the ontogeny and allometry of larval green and white sturgeon swimming capacities until completion of metamorphosis into juveniles. Despite the faster growth rates and eventual larger size of larval white sturgeon, green sturgeon critical swimming velocities remained consistently, though modestly, greater than those of white sturgeon throughout the larval life stage. Although behavioural interactions with water-diversion structures are also important considerations, regarding swimming capacity, Sacramento–San Joaquin sturgeons are most vulnerable to entrainment in February–May, when white sturgeon early larvae are in the middle Sacramento River, and April–May, when green sturgeon early larvae are in the upper river. Green sturgeon migrating downstream to the estuary and bays in October–November are also susceptible to entrainment due to their movements combined with seasonal declines in their swimming capacity. An additional inter-species comparison of the allometric relationship between critical swimming velocities and total length with several sturgeon species found throughout the world suggests a similar ontogeny of swimming capacity with growth. Therefore, although dispersal and behaviour differ among river systems and sturgeon species, similar recommendations are

  18. Cross-species comparison of relative potencies and relative sensitivities of fishes to dibenzo-p-dioxins, dibenzofurans, and polychlorinated biphenyls in vitro.

    PubMed

    Eisner, Bryanna K; Doering, Jon A; Beitel, Shawn C; Wiseman, Steve; Raine, Jason C; Hecker, Markus

    2016-01-01

    Dioxin-like compounds of varying toxicities are found in complex mixtures. The toxic equivalency factor (TEF) approach was developed based on the potency of a dioxin-like compound relative to the potency of 2,3,7,8-tetrachloro-dibenzo-p-dioxin (TCDD) to streamline risk assessment. One limitation of the TEF approach is uncertainty regarding differences in the relative potency of dioxin-like compounds among different species. Relative potencies among fishes are limited, relative to relative potencies among birds and mammals, and TEFs for fishes are based entirely on the model species, rainbow trout (Oncorhynchus mykiss). An in vitro liver explant assay was used to characterize species-specific responses with regard to up-regulation of CYP1A transcript after exposure to 6 dioxin-like compounds in rainbow trout, white sturgeon (Acipenser transmontanus), lake sturgeon (Acipenser fulvescens), and northern pike (Esox lucius). Differences in sensitivities were observed among species after exposure to dioxin-like compounds. The relative potencies developed from liver explants of rainbow trout were comparable to relative potencies developed from embryo toxicity assays. Differences in relative potencies between species with the least and greatest relative potencies were up to 40-fold. To compare relative potencies among species, concentrations of dioxin-like compounds in fish eggs in the Fraser River and in Lake Ontario were used to calculate toxic equivalency quotients (TEQs) determined from TEFs or TCDD equivalents determined from relative potencies. The TEQs underestimated TCDD equivalents for white sturgeon, lake sturgeon, and northern pike, indicating uncertainty in application of TEFs to diverse fishes.

  19. Shark fisheries in the Southeast Pacific: A 61-year analysis from Peru

    PubMed Central

    Gonzalez-Pestana, Adriana; Kouri J., Carlos; Velez-Zuazo, Ximena

    2016-01-01

    Peruvian waters exhibit high conservation value for sharks. This contrasts with a lag in initiatives for their management and a lack of studies about their biology, ecology and fishery. We investigated the dynamics of Peruvian shark fishery and its legal framework identifying information gaps for recommending actions to improve management. Further, we investigated the importance of the Peruvian shark fishery from a regional perspective. From 1950 to 2010, 372,015 tons of sharks were landed in Peru. From 1950 to 1969, we detected a significant increase in landings; but from 2000 to 2011 there was a significant decrease in landings, estimated at 3.5% per year. Six species represented 94% of landings: blue shark ( Prionace glauca), shortfin mako ( Isurus oxyrinchus), smooth hammerhead ( Sphyrna zygaena), common thresher ( Alopias vulpinus), smooth-hound ( Mustelus whitneyi) and angel shark ( Squatina californica). Of these, the angel shark exhibits a strong and significant decrease in landings: 18.9% per year from 2000 to 2010. Peru reports the highest accumulated historical landings in the Pacific Ocean; but its contribution to annual landings has decreased since 1968. Still, Peru is among the top 12 countries exporting shark fins to the Hong Kong market. Although the government collects total weight by species, the number of specimens landed as well as population parameters (e.g. sex, size and weight) are not reported. Further, for some genera, species-level identification is deficient and so overestimates the biomass landed by species and underestimates the species diversity. Recently, regional efforts to regulate shark fishery have been implemented to support the conservation of sharks but in Peru work remains to be done. PMID:27635216

  20. Biomimetic shark skin: design, fabrication and hydrodynamic function.

    PubMed

    Wen, Li; Weaver, James C; Lauder, George V

    2014-05-15

    Although the functional properties of shark skin have been of considerable interest to both biologists and engineers because of the complex hydrodynamic effects of surface roughness, no study to date has successfully fabricated a flexible biomimetic shark skin that allows detailed study of hydrodynamic function. We present the first study of the design, fabrication and hydrodynamic testing of a synthetic, flexible, shark skin membrane. A three-dimensional (3D) model of shark skin denticles was constructed using micro-CT imaging of the skin of the shortfin mako (Isurus oxyrinchus). Using 3D printing, thousands of rigid synthetic shark denticles were placed on flexible membranes in a controlled, linear-arrayed pattern. This flexible 3D printed shark skin model was then tested in water using a robotic flapping device that allowed us to either hold the models in a stationary position or move them dynamically at their self-propelled swimming speed. Compared with a smooth control model without denticles, the 3D printed shark skin showed increased swimming speed with reduced energy consumption under certain motion programs. For example, at a heave frequency of 1.5 Hz and an amplitude of ± 1 cm, swimming speed increased by 6.6% and the energy cost-of-transport was reduced by 5.9%. In addition, a leading-edge vortex with greater vorticity than the smooth control was generated by the 3D printed shark skin, which may explain the increased swimming speeds. The ability to fabricate synthetic biomimetic shark skin opens up a wide array of possible manipulations of surface roughness parameters, and the ability to examine the hydrodynamic consequences of diverse skin denticle shapes present in different shark species.

  1. Global versus local causes and health implications of high mercury concentrations in sharks from the east coast of South Africa.

    PubMed

    McKinney, Melissa A; Dean, Kylie; Hussey, Nigel E; Cliff, Geremy; Wintner, Sabine P; Dudley, Sheldon F J; Zungu, M Philip; Fisk, Aaron T

    2016-01-15

    Conservation concern regarding the overharvest of global shark populations for meat and fin consumption largely surrounds documented deleterious ecosystem effects, but may be further supported by improved knowledge of possibly high levels in their edible tissues (particularly meat) of the neurotoxin, methylmercury (CH3Hg). For many regions, however, little data exist on shark tissue Hg concentrations, and reasons for Hg variation within and among species or across regions are poorly understood. We quantified total Hg (THg) in 17 shark species (total n=283) from the east coast of South Africa, a top Hg emitter globally. Concentrations varied from means of around 0.1 mg kg(-1) dry weight (dw) THg in hardnose smoothhound (Mustelus mosis) and whale (Rhincodon typus) sharks to means of over 10 mg kg(-1) dw in shortfin mako (Isurus oxyrinchus), scalloped hammerhead (Sphyrna lewini), white (Carcharodon carcharias) and ragged-tooth (Carcharias taurus) sharks. These sharks had higher THg levels than conspecifics sampled from coastal waters of the North Atlantic and North, mid-, and South Pacific, and although sampling year and shark size may play a confounding role, this result suggests the potential importance of elevated local emissions. Values of THg showed strong, species-specific correlations with length, and nearly half the remaining variation was explained by trophic position (using nitrogen stable isotopes, δ(15)N), whereas measures of foraging habitat (using carbon stable isotopes, δ(13)C) were not significant. Mercury concentrations were above the regulatory guidelines for fish health effects and safe human consumption for 88% and 70% of species, respectively, suggesting on-going cause for concern for shark health, and human consumers of shark meat.

  2. Locational differences in mercury and selenium levels in 19 species of saltwater fish from New Jersey.

    PubMed

    Burger, Joanna; Jeitner, Christian; Gochfeld, Michael

    2011-01-01

    Individuals who fish, and their families that ingest self-caught fish, make decisions about where to fish, what type of fish to eat, and the quantity of fish to eat. While federal and state agencies often issue consumption advisories for some fish with high mercury (Hg) concentrations, advisories seldom provide the actual metal levels to the general public. There are few data for most saltwater fish, and even less information on variations in Hg levels in fish within a state or geographical region. The objective of this study was to provide Hg concentrations from 19 species of fish caught in different locations in New Jersey to (1) test the hypothesis that mean metal levels vary geographically, (2) provide this information to individuals who fish these coastal waters, and (3) provide a range of values for risk assessors who deal with saltwater fish exposure in the Northeastern United States. Selenium (Se) was also examined because of its purported moderating effect on the toxicity of Hg. Hg levels showed significant geographical variation for 10 of 14 species that were caught in more than one region of New Jersey, but there were significant locational differences for Se in only 5 of the fish. Mercury levels were significantly lower in fish collected from northern New Jersey (except for ling, Molva molva), compared to other regions. As might be expected, locational differences in Hg levels were greatest for fish species with the highest Hg concentrations (shark, Isurus oxyrinchus; tuna, Thunnus thynnus and T. albacares; striped bass, Morone saxatilis; bluefish, Pomatomus saltatrix). Fishers and their families might reduce their risk from Hg exposure not only by selecting fish generally lower in Hg, but by fishing predominantly in some regions over others, further lowering the potential risk. Health professionals might use these data to advise patients on which fish are safest to consume (in terms of Hg exposure) from particular geographical regions.

  3. Big catch, little sharks: Insight into Peruvian small-scale longline fisheries

    PubMed Central

    Doherty, Philip D; Alfaro-Shigueto, Joanna; Hodgson, David J; Mangel, Jeffrey C; Witt, Matthew J; Godley, Brendan J

    2014-01-01

    Shark take, driven by vast demand for meat and fins, is increasing. We set out to gain insights into the impact of small-scale longline fisheries in Peru. Onboard observers were used to document catch from 145 longline fishing trips (1668 fishing days) originating from Ilo, southern Peru. Fishing effort is divided into two seasons: targeting dolphinfish (Coryphaena hippurus; December to February) and sharks (March to November). A total of 16,610 sharks were observed caught, with 11,166 identified to species level. Of these, 70.6% were blue sharks (Prionace glauca), 28.4% short-fin mako sharks (Isurus oxyrinchus), and 1% were other species (including thresher (Alopias vulpinus), hammerhead (Sphyrna zygaena), porbeagle (Lamnus nasus), and other Carcharhinidae species (Carcharhinus brachyurus, Carcharhinus falciformis, Galeorhinus galeus). Mean ± SD catch per unit effort of 33.6 ± 10.9 sharks per 1000 hooks was calculated for the shark season and 1.9 ± 3.1 sharks per 1000 hooks were caught in the dolphinfish season. An average of 83.7% of sharks caught (74.7% blue sharks; 93.3% mako sharks) were deemed sexually immature and under the legal minimum landing size, which for species exhibiting k-selected life history traits can result in susceptibility to over exploitation. As these growing fisheries operate along the entire Peruvian coast and may catch millions of sharks per annum, we conclude that their continued expansion, along with ineffective legislative approaches resulting in removal of immature individuals, has the potential to threaten the sustainability of the fishery, its target species, and ecosystem. There is a need for additional monitoring and research to inform novel management strategies for sharks while maintaining fisher livelihoods. PMID:25360274

  4. DNA Barcoding of Shark Meats Identify Species Composition and CITES-Listed Species from the Markets in Taiwan

    PubMed Central

    Liu, Shang-Yin Vanson; Chan, Chia-Ling Carynn; Lin, Oceana; Hu, Chieh-Shen; Chen, Chaolun Allen

    2013-01-01

    Background An increasing awareness of the vulnerability of sharks to exploitation by shark finning has contributed to a growing concern about an unsustainable shark fishery. Taiwan’s fleet has the 4th largest shark catch in the world, accounting for almost 6% of the global figures. Revealing the diversity of sharks consumed by Taiwanese is important in designing conservation plans. However, fins make up less than 5% of the total body weight of a shark, and their bodies are sold as filets in the market, making it difficult or impossible to identify species using morphological traits. Methods In the present study, we adopted a DNA barcoding technique using a 391-bp fragment of the mitochondrial cytochrome oxidase I (COI) gene to examine the diversity of shark filets and fins collected from markets and restaurants island-wide in Taiwan. Results Amongst the 548 tissue samples collected and sequenced, 20 major clusters were apparent by phylogenetic analyses, each of them containing individuals belonging to the same species (most with more than 95% bootstrap values), corresponding to 20 species of sharks. Additionally, Alopias pelagicus, Carcharhinus falciformis, Isurus oxyrinchus, and Prionace glauca consisted of 80% of the samples we collected, indicating that these species might be heavily consumed in Taiwan. Approximately 5% of the tissue samples used in this study were identified as species listed in CITES Appendix II, including two species of Sphyrna, C. longimanus and Carcharodon carcharias. Conclusion DNA barcoding provides an alternative method for understanding shark species composition when species-specific data is unavailable. Considering the global population decline, stock assessments of Appendix II species and highly consumed species are needed to accomplish the ultimate goal of shark conservation. PMID:24260209

  5. LOCATIONAL DIFFERENCES IN MERCURY AND SELENIUM LEVELS IN 19 SPECIES OF SALTWATER FISH FROM NEW JERSEY

    PubMed Central

    Burger, Joanna; Jeitner, Christian; Gochfeld, Michael

    2014-01-01

    Individuals who fish, and their families that ingest self-caught fish, make decisions about where to fish, what type of fish to eat, and the quantity of fish to eat. While federal and state agencies often issue consumption advisories for some fish with high mercury (Hg) concentrations, advisories seldom provide the actual metal levels to the general public. There are few data for most saltwater fish, and even less information on variations in Hg levels in fish within a state or geographical region. The objective of this study was to provide Hg concentrations from 19 species of fish caught in different locations in New Jersey to (1) test the hypothesis that mean metal levels vary geographically, (2) provide this information to individuals who fish these coastal waters, and (3) provide a range of values for risk assessors who deal with saltwater fish exposure in the Northeastern United States. Selenium (Se) was also examined because of its purported moderating effect on the toxicity of Hg. Hg levels showed significant geographical variation for 10 of 14 species that were caught in more than one region of New Jersey, but there were significant locational differences for Se in only 5 of the fish. Mercury levels were significantly lower in fish collected from northern New Jersey (except for ling, Molva molva), compared to other regions. As might be expected, locational differences in Hg levels were greatest for fish species with the highest Hg concentrations (shark, Isurus oxyrinchus; tuna, Thunnus thynnus and T. albacares; striped bass, Morone saxatilis; bluefish, Pomatomus saltatrix). Fishers and their families might reduce their risk from Hg exposure not only by selecting fish generally lower in Hg, but by fishing predominantly in some regions over others, further lowering the potential risk. Health professionals might use these data to advise patients on which fish are safest to consume (in terms of Hg exposure) from particular geographical regions. PMID:21598171

  6. Shark fisheries in the Southeast Pacific: A 61-year analysis from Peru.

    PubMed

    Gonzalez-Pestana, Adriana; Kouri J, Carlos; Velez-Zuazo, Ximena

    2014-01-01

    Peruvian waters exhibit high conservation value for sharks. This contrasts with a lag in initiatives for their management and a lack of studies about their biology, ecology and fishery. We investigated the dynamics of Peruvian shark fishery and its legal framework identifying information gaps for recommending actions to improve management. Further, we investigated the importance of the Peruvian shark fishery from a regional perspective. From 1950 to 2010, 372,015 tons of sharks were landed in Peru. From 1950 to 1969, we detected a significant increase in landings; but from 2000 to 2011 there was a significant decrease in landings, estimated at 3.5% per year. Six species represented 94% of landings: blue shark ( Prionace glauca), shortfin mako ( Isurus oxyrinchus), smooth hammerhead ( Sphyrna zygaena), common thresher ( Alopias vulpinus), smooth-hound ( Mustelus whitneyi) and angel shark ( Squatina californica). Of these, the angel shark exhibits a strong and significant decrease in landings: 18.9% per year from 2000 to 2010. Peru reports the highest accumulated historical landings in the Pacific Ocean; but its contribution to annual landings has decreased since 1968. Still, Peru is among the top 12 countries exporting shark fins to the Hong Kong market. Although the government collects total weight by species, the number of specimens landed as well as population parameters (e.g. sex, size and weight) are not reported. Further, for some genera, species-level identification is deficient and so overestimates the biomass landed by species and underestimates the species diversity. Recently, regional efforts to regulate shark fishery have been implemented to support the conservation of sharks but in Peru work remains to be done.

  7. Big catch, little sharks: Insight into Peruvian small-scale longline fisheries.

    PubMed

    Doherty, Philip D; Alfaro-Shigueto, Joanna; Hodgson, David J; Mangel, Jeffrey C; Witt, Matthew J; Godley, Brendan J

    2014-06-01

    Shark take, driven by vast demand for meat and fins, is increasing. We set out to gain insights into the impact of small-scale longline fisheries in Peru. Onboard observers were used to document catch from 145 longline fishing trips (1668 fishing days) originating from Ilo, southern Peru. Fishing effort is divided into two seasons: targeting dolphinfish (Coryphaena hippurus; December to February) and sharks (March to November). A total of 16,610 sharks were observed caught, with 11,166 identified to species level. Of these, 70.6% were blue sharks (Prionace glauca), 28.4% short-fin mako sharks (Isurus oxyrinchus), and 1% were other species (including thresher (Alopias vulpinus), hammerhead (Sphyrna zygaena), porbeagle (Lamnus nasus), and other Carcharhinidae species (Carcharhinus brachyurus, Carcharhinus falciformis, Galeorhinus galeus). Mean ± SD catch per unit effort of 33.6 ± 10.9 sharks per 1000 hooks was calculated for the shark season and 1.9 ± 3.1 sharks per 1000 hooks were caught in the dolphinfish season. An average of 83.7% of sharks caught (74.7% blue sharks; 93.3% mako sharks) were deemed sexually immature and under the legal minimum landing size, which for species exhibiting k-selected life history traits can result in susceptibility to over exploitation. As these growing fisheries operate along the entire Peruvian coast and may catch millions of sharks per annum, we conclude that their continued expansion, along with ineffective legislative approaches resulting in removal of immature individuals, has the potential to threaten the sustainability of the fishery, its target species, and ecosystem. There is a need for additional monitoring and research to inform novel management strategies for sharks while maintaining fisher livelihoods.

  8. Identification of shark species composition and proportion in the Hong Kong shark fin market based on molecular genetics and trade records.

    PubMed

    Clarke, Shelley C; Magnussen, Jennifer E; Abercrombie, Debra L; McAllister, Murdoch K; Shivji, Mahmood S

    2006-02-01

    The burgeoning and largely unregulated trade in shark fins represents one of the most serious threats to shark populations worldwide. In Hong Kong, the world's largest shark fin market, fins are classified by traders into Chinese-name categories on the basis of market value, but the relationship between market category and shark species is unclear preventing identification of species that are the most heavily traded. To delineate these relationships, we designed a sampling strategy for collecting statistically sufficient numbers of fins from traders and categories under conditions of limited market access because of heightened trader sensitivities. Based on information from traders and morphological inspection, we hypothesized matches between market names and shark taxa for fins within 11 common trade categories. These hypotheses were tested using DNA-based species identification techniques to determine the concordance between market category and species. Only 14 species made up approximately 40% of the auctioned fin weight. The proportion of samples confirming the hypothesized match, or concordance, varied from 0.64 to 1 across the market categories. We incorporated the concordance information and available market auction records for these categories into stochastic models to estimate the contribution of each taxon by weight to the fin trade. Auctioned fin weight was dominated by the blue shark (Prionace glauca), which was 17% of the overall market. Other taxa, including the shortfin mako (Isurus oxyrinchus), silky (Carcharhinus falciformis), sandbar (C. obscurus), bull (C. leucas), hammerhead (Sphyrna spp.), and thresher (Alopias spp.), were at least 2-6% of the trade. Our approach to marketplace monitoring of wildlife products isparticularly applicable to situations in which quantitative data at the source of resource extraction are sparse and large-scale genetic testing is limited by budgetary or other market access constraints.

  9. Estimating Finite Rate of Population Increase for Sharks Based on Vital Parameters

    PubMed Central

    Liu, Kwang-Ming; Chin, Chien-Pang; Chen, Chun-Hui; Chang, Jui-Han

    2015-01-01

    The vital parameter data for 62 stocks, covering 38 species, collected from the literature, including parameters of age, growth, and reproduction, were log-transformed and analyzed using multivariate analyses. Three groups were identified and empirical equations were developed for each to describe the relationships between the predicted finite rates of population increase (λ’) and the vital parameters, maximum age (Tmax), age at maturity (Tm), annual fecundity (f/Rc)), size at birth (Lb), size at maturity (Lm), and asymptotic length (L∞). Group (1) included species with slow growth rates (0.034 yr-1 < k < 0.103 yr-1) and extended longevity (26 yr < Tmax < 81 yr), e.g., shortfin mako Isurus oxyrinchus, dusky shark Carcharhinus obscurus, etc.; Group (2) included species with fast growth rates (0.103 yr-1 < k < 0.358 yr-1) and short longevity (9 yr < Tmax < 26 yr), e.g., starspotted smoothhound Mustelus manazo, gray smoothhound M. californicus, etc.; Group (3) included late maturing species (Lm/L∞ ≧ 0.75) with moderate longevity (Tmax < 29 yr), e.g., pelagic thresher Alopias pelagicus, sevengill shark Notorynchus cepedianus. The empirical equation for all data pooled was also developed. The λ’ values estimated by these empirical equations showed good agreement with those calculated using conventional demographic analysis. The predictability was further validated by an independent data set of three species. The empirical equations developed in this study not only reduce the uncertainties in estimation but also account for the difference in life history among groups. This method therefore provides an efficient and effective approach to the implementation of precautionary shark management measures. PMID:26576058

  10. G. J. Billberg's (1833) 'On the ichthyology, and description of some new fish species of the pipefish genus Syngnathus'.

    PubMed

    Kullander, Sven O

    2016-01-14

    broussonetii, Acipenser vulgaris, and Acipenser ichthyocolla.        Three species of pipefishes of the family Syngnathidae are described and figured by Billberg from drawings of specimens observed on the Swedish West Coast. Syngnathus virens and S. pustulatus are junior synonyms of S. typhle Linnaeus, 1758. Syngnathus palmstruchii is a junior synonym of Entelurus aequoreus (Linnaeus, 1758).

  11. High-throughput SNP-genotyping analysis of the relationships among Ponto-Caspian sturgeon species

    PubMed Central

    Rastorguev, Sergey M; Nedoluzhko, Artem V; Mazur, Alexander M; Gruzdeva, Natalia M; Volkov, Alexander A; Barmintseva, Anna E; Mugue, Nikolai S; Prokhortchouk, Egor B

    2013-01-01

    Abstract Legally certified sturgeon fisheries require population protection and conservation methods, including DNA tests to identify the source of valuable sturgeon roe. However, the available genetic data are insufficient to distinguish between different sturgeon populations, and are even unable to distinguish between some species. We performed high-throughput single-nucleotide polymorphism (SNP)-genotyping analysis on different populations of Russian (Acipenser gueldenstaedtii), Persian (A. persicus), and Siberian (A. baerii) sturgeon species from the Caspian Sea region (Volga and Ural Rivers), the Azov Sea, and two Siberian rivers. We found that Russian sturgeons from the Volga and Ural Rivers were essentially indistinguishable, but they differed from Russian sturgeons in the Azov Sea, and from Persian and Siberian sturgeons. We identified eight SNPs that were sufficient to distinguish these sturgeon populations with 80% confidence, and allowed the development of markers to distinguish sturgeon species. Finally, on the basis of our SNP data, we propose that the A. baerii-like mitochondrial DNA found in some Russian sturgeons from the Caspian Sea arose via an introgression event during the Pleistocene glaciation. In the present study, the high-throughput genotyping analysis of several sturgeon populations was performed. SNP markers for species identification were defined. The possible explanation of the baerii-like mitotype presence in some Russian sturgeons in the Caspian Sea was suggested. PMID:24567827

  12. Influence of a weak field of pulsed DC electricity on the behavior and incidence of injury in adult Steelhead and Pacific Lamprey

    USGS Publications Warehouse

    Mesa, Matthew G.; Copeland, Elizabeth S.

    2009-01-01

    Predation by pinnipeds, such as California sea lions Zalophus californianus, Pacific harbor seals Phoca vitulina, and Stellar sea lions Eumetopias jubatus on adult Pacific salmon Oncorhynchus spp in the lower Columbia River has become a serious concern for fishery managers trying to conserve and restore runs of threatened and endangered fish. As a result, Smith-Root, Incorporated (SRI; Vancouver, Washington), manufacturers of electrofishing and closely-related equipment, proposed a project to evaluate the potential of an electrical barrier to deter marine mammals and reduce the amount of predation on adult salmonids (SRI 2007). The objectives of their work were to develop, deploy, and evaluate a passive, integrated sonar and electric barrier that would selectively inhibit the upstream movements of marine mammals and reduce predation, but would not injure pinnipeds or impact anadromous fish migrations. However, before such a device could be deployed in the field, concerns by regional fishery managers about the potential effects of such a device on the migratory behavior of Pacific salmon, steelhead O. mykiss, Pacific lampreys Entoshpenus tridentata, and white sturgeon Acipenser transmontanus, needed to be addressed. In this report, we describe the results of laboratory research designed to evaluate the effects of prototype electric barriers on adult steelhead and Pacific lampreys.

  13. Sediment cores and chemistry for the Kootenai River White Sturgeon Habitat Restoration Project, Boundary County, Idaho

    USGS Publications Warehouse

    Barton, Gary J.; Weakland, Rhonda J.; Fosness, Ryan L.; Cox, Stephen E.; Williams, Marshall L.

    2012-01-01

    The Kootenai Tribe of Idaho, in cooperation with local, State, Federal, and Canadian agency co-managers and scientists, is assessing the feasibility of a Kootenai River habitat restoration project in Boundary County, Idaho. This project is oriented toward recovery of the endangered Kootenai River white sturgeon (Acipenser transmontanus) population, and simultaneously targets habitat-based recovery of other native river biota. Projects currently (2010) under consideration include modifying the channel and flood plain, installing in-stream structures, and creating wetlands to improve the physical and biological functions of the ecosystem. River restoration is a complex undertaking that requires a thorough understanding of the river. To assist in evaluating the feasibility of this endeavor, the U.S. Geological Survey collected and analyzed the physical and chemical nature of sediment cores collected at 24 locations in the river. Core depths ranged from 4.6 to 15.2 meters; 21 cores reached a depth of 15.2 meters. The sediment was screened for the presence of chemical constituents that could have harmful effects if released during restoration activities. The analysis shows that concentrations of harmful chemical constituents do not exceed guideline limits that were published by the U.S. Army Corps of Engineers in 2006.

  14. Characterization and inhibition of nitrite uptake in shortnose sturgeon fingerlings

    USGS Publications Warehouse

    Fontenot, Q.C.; Isely, J.J.; Tomasso, J.R.

    1999-01-01

    Efforts are underway to culture the endangered shortnose sturgeon Acipenser brevirostrum for possible reintroduction. As part of a larger project to develop culture techniques for this species, the uptake of nitrite was evaluated in fingerlings (16.5 ?? 4.85 g; mean ?? SD). Plasma nitrite concentrations increased significantly with exposure time (0-5 d) and dose (0-4 mg nitrite-N/L). Shortnose sturgeon fingerlings were able to concentrate nitrite in their plasma to more than 63 times the environmental concentration. Chloride, as either sodium chloride or calcium chloride, partially inhibited nitrite uptake. However, calcium chloride was a better inhibitor. After previous exposure (2 d at 2.13 ?? 0.080 mg nitrite-N/L) plasma nitrite-N decreased from 165.5 to 36.7 mg/L during a 3-d simultaneous exposure to 2.13 ?? 0.080 mg nitrite-N/L and treatment with 40 mg chloride/L as calcium chloride. The addition of calcium chloride to the water appeared to be an effective means of preventing nitrite uptake and treating nitrite toxicity in hatchery-reared shortnose sturgeon fingerlings.

  15. Age, growth, mortality, and abundance of lake sturgeon in the Grasse River, New York, USA

    USGS Publications Warehouse

    Trested, D.G.; Isely, J.J.

    2011-01-01

    An increased understanding of lake sturgeon (Acipenser fulvescens) population dynamics is a key requirement for successful management efforts. Little is known regarding the Grasse River population of lake sturgeon except that it is one of a few populations in New York State where spawning has been documented. Thus our purpose was to assess the current status of lake sturgeon in the Grasse River system, including age, growth, mortality, and abundance. Age was determined for 196 of 211 lake sturgeon by examination of sectioned pectoral fin rays. Ages ranged from 0 to 32 years and the annual mortality rate for fish between ages 7 and 14 was 16.8%. The weight (W, g) to total length (TL, mm) relationship was W = 1.281 x 10-6TL3.202. The von Bertalanffy growth equation was TL = 1913(1-e-0.0294(t+9.5691)). While the range of observed ages was similar to that of nearby St. Lawrence River populations, mean weight at age for an individual at 1000 mm TL was lower than that observed for lake sturgeon within Lake St. Francis of the St. Lawrence River. Predicted growth based on von Bertalanffy parameters was similar to that observed for the nearby Lake St. Francis. An open population estimator using the POPAN sub-module in the Program MARK produced an abundance estimate of 793 lake sturgeon (95% CI = 337-1249).

  16. Short-term response of subadult white sturgeon to hopper dredge disposal operations

    USGS Publications Warehouse

    Parsley, Michael J.; Popoff, Nicholas D.; Romine, Jason G.

    2011-01-01

    The effect of dredged-material disposal operations on the behavior of seven white sturgeon Acipenser transmontanus (50–101 cm fork length) was examined by analysis of the movements and depth use of these fish before, during, and after a series of hopper dredge disposal operations in the lower Columbia River. Analyses of fish locations showed that 12 flow-lane disposal operations within a 24-h period had minimal effect on subadult white sturgeon behavior; six of the seven fish showed slight attraction to the disposal area during disposals, and one fish increased its distance from the disposal area. The core area for all fish combined shifted toward the disposal area during disposals. In the 24 h after completion of the disposal operations the fish core areas shifted back toward those areas occupied before the disposals. The rates of movement, depths used, and diel movement patterns of the white sturgeon showed little change over all periods, suggesting that natural behaviors were not altered during and immediately after hopper dredge disposal operations.

  17. Spawning and rearing habitat use by white sturgeons in the Columbia River downstream from McNary Dam

    SciTech Connect

    Parsley, M.J.; Beckman, L.G. )

    1993-03-01

    Spawning and rearing habitats used by white sturgeons Acipenser transmontanus were described from water temperature, depth, and velocity measurements and substrate types present at sites where eggs, larvae, young-of-the-year, and juveniles (ages 1-7) were collected. Spawning and egg incubation occurred in the swiftest water available (mean water column velocity, 0.8-2.8 m/s), which was within 8 km downstream from each of the four main-stem Columbia River dams in our study area. Substrates where spawning occurred mainly cobble, boulder, and bedrock. Yolk-sac larvae were transported by the river currents from spawning areas into deeper areas with lower water velocities and finer substrates. Young-of-the-year white sturgeons were found at depths of 9-57 m, at mean water column velocities of 0.6 m/s and less, and over substrates of hard clay, mud and silt, sand, gravel, and cobble. Juvenile fish were found at depths of 2-58 m, at mean water column velocities of 1.2 m/s and less, and over substrates of hard clay, mud and silt, sand, gravel, cobble, boulder, and bedrock. 38 refs., 9 figs., 2 tabs.

  18. The effects of dissolved gas supersaturation on white sturgeon larvae

    USGS Publications Warehouse

    Counihan, T.D.; Miller, A.I.; Mesa, M.G.; Parsley, M.J.

    2000-01-01

    Spill at dams has caused supersaturation of atmospheric gas in waters of the Columbia and Snake rivers and raised concerns about the effects of dissolved gas supersaturation (DGS) on white sturgeons Acipenser transmontanus. The timing and location of white sturgeon spawning and the dispersal of white sturgeon larvae from incubation areas makes the larval stage potentially vulnerable to the effects of DGS. To assess the effects of DGS on white sturgeon larvae, we exposed larvae to mean total dissolved gas (TDG) levels of 118% and 131% saturation in laboratory bioassay tests. Gas bubble trauma (GBT) was manifested as a gas bubble in the buccal cavity, nares, or both and it first occurred at developmental stages characterized by the formation of the mouth and gills. Exposure times of 15 min were sufficient to elicit these signs in larvae in various stages of development. No mortality was observed in larvae exposed to 118% TDG for 10 d, but 50% mortality occurred after a 13-d exposure to 131% TDG. The signs of GBT we observed resulted in positive buoyancy and alterations in behavior that may affect the dispersal and predation vulnerability of white sturgeon larvae. The exact depth distribution of dispersing white sturgeon larvae in the Columbia River currently is unknown. Thus, our results may represent a worst-case scenario if white sturgeon larvae are dispersed at depths with insufficient hydrostatic pressure to compensate for high TDG levels.

  19. Evaluate Potential Means of Rebuilding Sturgeon Populations in the Snake River between Lower Granite and Hells Canyon Dams, 1998 Annual Report.

    SciTech Connect

    Everett, Scott R.; Tuell, Michael A.

    2002-03-01

    In 1998 white sturgeon (Acipenser transmontanus) were captured, marked, and population data were collected in the Snake River between Lower Granite Dam and the mouth of the Salmon River. A total of 13,785 hours of setline effort and 389 hours of hook-and-line effort was employed in 1998. Of the 278 white sturgeon captured in the Snake River, 238 were marked for future identification. Three sturgeon were captured in the Salmon River and none were captured in the Clearwater River. Since 1997, 6.9% of the tagged fish have been recovered. Movement of recaptured white sturgeon ranged from 98.5 kilometers downstream to 60.7 kilometers upstream, however, less than 25% of the fish moved more than 16 kilometers (10 miles). In the Snake River, white sturgeon ranged in total length from 51.5 cm to 286 cm and averaged 118.9 cm. Differences were detected in the length frequency distributions of sturgeon in Lower Granite Reservoir and the free-flowing Snake River (Chi-Square test, P < 0.05). In addition, the proportion of white sturgeon greater than 92 cm (total length) in the free-flowing Snake River has shown an increase of 37% since the 1970's. Analysis of the length-weight relationship indicated that white sturgeon in Lower Granite Reservoir were slightly larger than white sturgeon in the free-flowing Snake River.

  20. Effects of turbidity, light level, and cover on predation of white sturgeon larvae by prickly sculpins

    USGS Publications Warehouse

    Gadomski, D.M.; Parsley, M.J.

    2005-01-01

    White sturgeon Acipenser transmontanus occur in rivers of the western United States and southwestern Canada, but some populations are in decline because of recruitment failure. Many river systems in this area have been altered as a result of development that has caused major environmental changes. Our goal was to examine how three changes - lower turbidity levels, higher light levels, and altered substrates - might affect predation by prickly sculpin Cottus asper on white sturgeon larvae. We experimentally investigated predation at various turbidity levels and found that significantly more white sturgeon yolk sac larvae were eaten at lower turbidity levels. The effects of light level (1-4 and 7-15 1x), the presence or absence of rocks as cover, and prey size (14-17 mm and 20-24 mm total length) on the outcome of predator-prey interactions were also examined. Significantly fewer white sturgeon were eaten during trials that combined the lowest light level, cover, and the smallest larvae. Our results suggest that altered river conditions caused by impoundment and other factors have increased predation on white sturgeon larvae. ?? Copyright by the American Fisheries Society 2005.

  1. Seasonal and diel movements of white sturgeon in the lower columbia river

    USGS Publications Warehouse

    Parsley, M.J.; Popoff, N.D.; Van Der Leeuw, B. K.; Wright, C.D.

    2008-01-01

    Continuous monitoring of the movements and depths used by white sturgeon Acipenser transmontanus with acoustic telemetry technologies in the lower Columbia River provided information on diel and seasonal migrations, local movements, and site fidelity. White sturgeon moved to shallower water at night and showed greater activity, inferred from rates of movement, than during daytime. The extent of local movement within a season was variable among fish; some fish readily moved among habitats while the movements of others were more constrained. White sturgeon were absent from the study area (river kilometers 45-52) during winter and returned from upstream during the spring, confirming an upstream seasonal migration in the fall and downstream migration in spring. The return of individual fish and reoccupation of areas previously inhabited showed that some white sturgeon exhibit site fidelity. This work shows that studies seeking to characterize habitat for white sturgeon need to be cognizant of diel migrations and site fidelity. We urge caution in the use of limited fish location data to describe habitats if diel activities and fine-scale movements are not known.

  2. Spawning and rearing habitat use by white sturgeons in the Columbia River downstream from McNary Dam

    USGS Publications Warehouse

    Parsley, Michael J.; Beckman, Lance G.; McCabe, George T.

    1993-01-01

    Spawning and rearing habitats used by white sturgeons Acipenser transmontanuswere described from water temperature, depth, and velocity measurements and substrate types present at sites where eggs, larvae, young-of-the-year, and juveniles (ages 1–7) were collected. Spawning and egg incubation occurred in the swiftest water available (mean water column velocity, 0.8–2.8 m/s), which was within 8 km downstream from each of the four main-stem Columbia River dams in our study area. Substrates where spawning occurred were mainly cobble, boulder, and bedrock. Yolk-sac larvae were transported by the river currents from spawning areas into deeper areas with lower water velocities and finer substrates. Young-of-the-year white sturgeons were found at depths of 9–57 m, at mean water column velocities of 0.6 m/s and less, and over substrates of hard clay, mud and silt, sand, gravel, and cobble. Juvenile fish were found at depths of 2–58 m, at mean water column velocities of 1.2 m/s and less, and over substrates of hard clay, mud and silt, sand, gravel, cobble, boulder, and bedrock.

  3. A spatial model of white sturgeon rearing habitat in the lower Columbia River, USA

    USGS Publications Warehouse

    Hatten, J.R.; Parsley, M.J.

    2009-01-01

    Concerns over the potential effects of in-water placement of dredged materials prompted us to develop a GIS-based model that characterizes in a spatially explicit manner white sturgeon Acipenser transmontanus rearing habitat in the lower Columbia River, USA. The spatial model was developed using water depth, riverbed slope and roughness, fish positions collected in 2002, and Mahalanobis distance (D2). We created a habitat suitability map by identifying a Mahalanobis distance under which >50% of white sturgeon locations occurred in 2002 (i.e., high-probability habitat). White sturgeon preferred relatively moderate to high water depths, and low to moderate riverbed slope and roughness values. The eigenvectors indicated that riverbed slope and roughness were slightly more important than water depth, but all three variables were important. We estimated the impacts that fill might have on sturgeon habitat by simulating the addition of fill to the thalweg, in 3-m increments, and recomputing Mahalanobis distances. Channel filling simulations revealed that up to 9 m of fill would have little impact on high-probability habitat, but 12 and 15 m of fill resulted in habitat declines of ???12% and ???45%, respectively. This is the first spatially explicit predictive model of white sturgeon rearing habitat in the lower Columbia River, and the first to quantitatively predict the impacts of dredging operations on sturgeon habitat. Future research should consider whether water velocity improves the accuracy and specificity of the model, and to assess its applicability to other areas in the Columbia River.

  4. Idaho Water Rental Pilot Project Probability/Coordination Study Resident Fish and Wildlife Impacts Phase III, 1996 Annual Report.

    SciTech Connect

    Leitzinger, Eric J.

    1997-12-01

    Phase 3 began in 1995 with the overall goal of quantifying changes in resident fish habitat in the Snake River Basin upstream of Brownlee Reservoir resulting from the release of salmon flow augmentation water. Existing data, in the form of weighted usable area versus flow relationships, were used to estimate habitat changes for white sturgeon (Acipenser transinontanus) and rainbow trout (Oncorhynchus mykiss) in the Snake River between C.J. Strike Dam and Brownlee pool. The increased flows resulted in increased habitat for adult and juvenile white sturgeon and adult rainbow trout. But, the flows have failed to meet mean monthly flow recommendations for the past three years despite the addition of the flow augmentation releases. It is unlikely that the flow augmentation releases have had any significant long-term benefit for sturgeon and rainbow trout in the Snake River. Flow augmentation releases from the Boise and Payette rivers have in some years helped to meet or exceed minimum flow recommendations in these tributaries. The minimum flows would not have been reached without the flow augmentation releases. But, in some instances, the timing of the releases need to be adjusted in order to maximize benefits to resident fishes in the Boise and Payette rivers.

  5. Evaluation of four suture materials for surgical incision closure in Siberian sturgeon

    USGS Publications Warehouse

    Boone, S. Shaun; Hernandez, Sonia M.; Camus, Alvin C.; Peterson, Douglas C.; Jennings, Cecil A.; Shelton, James L.; Divers, Stephen J.

    2015-01-01

    The visual and microscopic tissue reactions to the absorbable monofilament Monocryl, absorbable monofilament triclosan-coated Monocryl-Plus, absorbable multifilament Vicryl, and nonabsorbable monofilament Prolene were evaluated for their use of surgical closure in Siberian Sturgeon Acipenser baerii. Postoperative assessments were conducted at 1, 2, 8, 12, and 26 and 55 weeks to visually evaluate the surgical incision for suture retention, incision healing, erythema, and swelling. Incisions were also assessed microscopically at 1, 2, and 8 weeks for necrosis, inflammation, hemorrhage, and fibroplasia. The results indicated that incisions closed with either Vicryl or Prolene suture materials were more likely to exhibit more erythema or incomplete healing compared with those closed with Monocryl or Monocryl-Plus. The surgical implantation of a transmitter in the coelomic cavity did not significantly affect the response variables among the four suture materials. Monocryl or Monocryl-Plus were equally effective and superior to other suture materials used for closing surgical incisions in Siberian Sturgeon or closely related species of sturgeon. Furthermore, Monocryl or Monocryl-Plus may decrease the risk of transmitter expulsion through the incision, as surgical wounds appear to heal faster and exhibit less erythema compared with those closed with Vicryl.

  6. Pathologic and physiologic effects associated with long-term intracoelomic transmitters in captive Siberian sturgeon

    USGS Publications Warehouse

    Boone, S. Shaun; Divers, Stephen J.; Camus, Alvin C.; Peterson, Douglas C.; Jennings, Cecil A.; Shelton, James L.; Hernandez, Sonia M.

    2015-01-01

    Intracoelomic transmitters are commonly used to evaluate migratory patterns, distribution, and habitat use of many species of fish. Currently, transmitter implantation relies mostly on the assumption that transmitters do not cause any adverse physiological or pathological effects on the animal. To investigate these effects, we surgically implanted 60 Siberian Sturgeon Acipenser baeri with transmitters that weighed less than 2% of their body weight. Postoperative assessments were conducted at 1, 2, 8, 12, 26, and 55 weeks to evaluate surgical healing and transmitter retention. Blood samples were collected before and after the 55-week study for serum cortisol analysis. Overall transmitter loss was 32%. Minor to moderate adhesions were noted at necropsy but did not appear to affect organ function. One fish was noted to have an intraintestinal transmitter at necropsy, but the fish was in overall good health. Long-term transmitter presence does not appear to increase serum cortisol levels or affect overall growth more than nontransmitter fish. Although long-term telemetry studies can be undertaken with minimal concern for negative physiological or pathological effects from transmitters, researchers should be aware that transmitter loss rates may be higher than previously thought. Mechanisms for transmitter loss may include expulsion through the surgical incision, expulsion through the mucocutaneous junction between the large intestine and the vent, or intraintestinal capture and expulsion through the vent. Received February 10, 2013; accepted June 10, 2013

  7. Distribution of lake sturgeon in New York: 11 years of restoration management

    USGS Publications Warehouse

    Chalupnicki, M.A.; Dittman, D.E.; Carlson, D.M.

    2011-01-01

    Lake sturgeon (Acipenser fulvescens) are native within the Lake Ontario drainage basin and listed as threatened by New York State. In 1995 the New York State Department of Environmental Conservation (NYSDEC) initiated restoration management of lake sturgeon. This management included both protection of extant populations and stocking of uninhabited historic waters with juvenile sturgeon. A list compiled by NYSDEC of observations of lake sturgeon from New York State waters for the period encompassing 1800-2005 was combined with recent observations through 2008 and formatted (Geographic Information System) to allow mapping of sturgeon geographical distribution. Distributions of pre- and post-restoration sturgeon were examined by occurrence and type of observation. Distribution patterns indicated lakes and rivers with current sturgeon presence have increased from five to eight, which was the first-phase goal of the New York Lake Sturgeon Recovery Plan. Lake sturgeon have started to expand into joining water to include the Indian R., Oneida R., Seneca R. and Oswego R. The protected historic populations in the Niagara R., Grasse R., St. Lawrence R., and Lakes Erie and Ontario continue to have low numbers of sturgeon observations. This summary of mapped lake sturgeon distribution information will help in guiding research assessments to waters containing substantial populations. These accessible reaches provide a generous advantage to the released juveniles as they move toward the next goal of restoration, spawning of sturgeon in targeted waters. ?? 2011 American Midland Naturalist.

  8. High-throughput SNP-genotyping analysis of the relationships among Ponto-Caspian sturgeon species.

    PubMed

    Rastorguev, Sergey M; Nedoluzhko, Artem V; Mazur, Alexander M; Gruzdeva, Natalia M; Volkov, Alexander A; Barmintseva, Anna E; Mugue, Nikolai S; Prokhortchouk, Egor B

    2013-08-01

    Legally certified sturgeon fisheries require population protection and conservation methods, including DNA tests to identify the source of valuable sturgeon roe. However, the available genetic data are insufficient to distinguish between different sturgeon populations, and are even unable to distinguish between some species. We performed high-throughput single-nucleotide polymorphism (SNP)-genotyping analysis on different populations of Russian (Acipenser gueldenstaedtii), Persian (A. persicus), and Siberian (A. baerii) sturgeon species from the Caspian Sea region (Volga and Ural Rivers), the Azov Sea, and two Siberian rivers. We found that Russian sturgeons from the Volga and Ural Rivers were essentially indistinguishable, but they differed from Russian sturgeons in the Azov Sea, and from Persian and Siberian sturgeons. We identified eight SNPs that were sufficient to distinguish these sturgeon populations with 80% confidence, and allowed the development of markers to distinguish sturgeon species. Finally, on the basis of our SNP data, we propose that the A. baerii-like mitochondrial DNA found in some Russian sturgeons from the Caspian Sea arose via an introgression event during the Pleistocene glaciation. In the present study, the high-throughput genotyping analysis of several sturgeon populations was performed. SNP markers for species identification were defined. The possible explanation of the baerii-like mitotype presence in some Russian sturgeons in the Caspian Sea was suggested.

  9. Response of spawning lake sturgeons to change in hydroelectric facility operation

    SciTech Connect

    Auer, N.A.

    1996-01-01

    Spawning of lake sturgeon Acipenser fulvescens was documented from 1987 to 1992 below the Prickett hydroelectric facility on the Sturgeon River, a tributary to Portage Lake, Michigan. Lake sturgeons were captured at the spawning site with dip nets during periods of reduced flow. A change in the spawning characteristics of the population was noted that corresponded to a changed in the operation of the hydroelectric facility. In 1987 and 1988 the facility operated in a peaking mode, which resulted in large daily fluctuations in river flows. The years 1989 and 1990 were years of transition, and in 1991 and 1992 the facility released near run-of-the-river (ROR) flows. Under near-ROR flows, which were more natural, adult lake sturgeons spent 4-6 weeks less at the spawning sites, 74% more fish were observed, weights were greater due to a 68% increase in number of females, and fish had increased reproductive readiness. The change in flow regime was the result of a Federal Energy Regulatory Commission relicensing action. The positive response observed in lake sturgeon spawning activity that resulted from the change of facility operation to near-ROR flows should be beneficial to the survival and perpetuation of this population. Similar results may be experienced in other lake sturgeon waters affected by manipulated flow regimes. 28 refs., 5 figs., 6 tabs.

  10. Evaluation of Reconnection Options for White Sturgeon in the Snake River Using a Population Viability Model

    SciTech Connect

    Jager, Yetta; Bevelhimer, Mark S; Chandler, James A.; Lepla, Ken B.; Van Winkle, Webb

    2007-01-01

    Abstract.- This paper describes a simulation study of reconnection options for white sturgeon Acipenser transmontanus subpopulations in adjacent river segments above and below CJ Strike Dam on the Snake River, Idaho, USA. In contrast to the downstream river segment, the upstream river segment is long and has areas that are suitable for spawning during normal and wet hydrologic conditions. We evaluated demographic and genetic consequences of upstream and downstream passage using different model assumptions about trashrack spacing and density dependent effects on the spawning interval. Our genetic results predict that, although reconnection would introduce new alleles to the upstream subpopulation, it would also preserve alleles from the downstream subpopulation by propagating them in the larger subpopulation above the dam. Our demographic results predict that halving the space between trashracks would have large and unequivocal benefits, whereas the effects of reconnection would be smaller and more sensitive to model assumptions. Simulated upstream passage tended to benefit both subpopulations only in the absence of density dependent limitation. In the presence of density dependence, the combination of halved trashrack spacing and upstream and downstream passage produced the best results. Narrower trashracks kept spawning adults in the upstream segment with spawning habitat, while allowing their progeny to migrate downstream. Screening appears to be the best option for such a species in this configuration of a long river segment acting as a demographic source above a short one acting as a demographic sink.

  11. Identification of sturgeon IgD bridges the evolutionary gap between elasmobranchs and teleosts.

    PubMed

    Zhu, Lin; Yan, Zhenxin; Feng, Mengyang; Peng, Dezhi; Guo, Ying; Hu, Xiaoxiang; Ren, Liming; Sun, Yi

    2014-02-01

    IgD has been found in almost all jawed vertebrates, including cartilaginous and teleost fish. However, IgD is missing in acipenseriformes, a branch that is evolutionarily positioned between elasmobranchs and teleost fish. Here, by analyzing transcriptome data, we identified a transcriptionally active IgD-encoding gene in the Siberian sturgeon (Acipenser baerii). Phylogenetic analysis indicated that it is orthologous to mammalian IgD and closely related to the IgD of other fish. The lengths of sturgeon membrane-bound IgD transcripts ranged from 1.2kb to 6.2kb, encoding 3-19 CH domains. As in teleosts, the first CH domain of the sturgeon IgD transcript is also derived from μCH1 by RNA splicing. However, the variable region of the expressed sturgeon IgD shows limited V(D)J usage. In addition to IgD, three IgM variants were also identified in this species, whereas no IgT/Z-encoding genes were observed. This study bridges the gap in Ig evolution between elasmobranchs and teleosts and provides significant insight into the early evolution of immunoglobulins.

  12. Biotransformation and detoxication of molinate (Ordram) in fish

    SciTech Connect

    Tjeerdema, R.S.

    1987-01-01

    Bioconcentration, deputation, and biotransformation of molinate were compared in common carp (cyprinus carpio), striped bass (Morone saxatilis), and white sturgeon (acipenser transmontanus) using a flow-through metabolism system. When compared to static conditions, flowing water improved oxygenation, decreased chemical volatilization and remetabolism, and run through a macroreticular resin, improved waste-product collection. Metabolite analysis employed gradient high-pressure liquid chromatography. Exposure to 100 ..mu..g L/sup -1/ (ring-/sup 14/C)molinate for 24 h resulted in bioconcentration factors of 30.5 (carp), 25.3 (bass), and 19.7 (sturgeon); differences were not significant (all, P > 0.05). /sup 14/C depuration by common carp was significantly slower than that by either striped bass or white sturgeon (both, P < 0.01). All three species oxidized molinate to a number of products and hydrolyzed, or conjugated with glutathione (GSH), the sulfoxide or sulfone, ultimately producing the mercapturic acid; carp and sturgeon also formed a D-glucuronic acid conjugate. Common carp were significantly less capable of sulfoxidation and GSH conjugation than either striped bass (P < 0.05) or white sturgeon (P < 0.01). Therefore, the selective toxicity of molinate in carp may be due to less efficient depuration and metabolic deactivation.

  13. Turnover of hydrogen isotopes in lake sturgeon blood: implications for tracking movements of wild populations.

    PubMed

    Kreitals, Natasha M; Hobson, Keith A; Hoemsen, Brittney M; Crane, Adam L; Wishingrad, Van; Sloychuk, Janelle; Pollock, Michael S; Chivers, Douglas P; Phillips, Iain D

    2016-12-01

    Naturally occurring deuterium ((2)H) in biota can be used to trace movement, migration and geographic origin of a range of organisms. However, to evaluate movements of animals using δ(2)H measurements of tissues, it is necessary to establish the turnover time of (2)H in the tissues and the extent of isotopic discrimination from different environmental (2)H sources to those tissues. We investigated the turnover of (2)H in lake sturgeon (Acipenser fulvescens) blood by manipulating both environmental water δ(2)H and diet δ(2)H over a four-month period. The half-life of deuterium in lake sturgeon blood was 37.9 days after an increase in the environmental water δ(2)H of +714 ‰. However, no clear turnover in blood (2)H occurred over the same period in a separate trial following a change of -63.8 ‰ or +94.2 ‰ in diet. These findings suggest that environmental water (2)H exchanges much faster with blood than diets and that blood δ(2)H values can be used to trace movements of sturgeon and other fish moving among isotopically distinct waters.

  14. Differences in the dynamics and potential production of impounded and unimpounded white sturgeon populations in the lower Columbia River

    SciTech Connect

    Beamesderfer, R.C.P.; Rien, T.A.; Nigro, A.A.

    1995-11-01

    White sturgeons Acipenser transmontanus were sampled in three lower Columbia River reservoirs from 1987 to 1991 to describe population dynamics, the ability of these stocks to sustain harvest, and differences among reservoir and unimpounded populations. Significant differences were observed among reservoirs in white sturgeon abundance, biomass, size composition, sex ratio, size of females at maturity, growth rate, condition factor, and rate of exploitation. No differences among reservoirs were detected in fecundity, natural mortality rate, or longevity, in part because of sampling difficulties. Recruitment rates and densities in reservoirs were inversely correlated with growth rate, condition factor, and size of females at maturity. Differences in population dynamics resulted in substantial differences in sustainable yields. Maximum yields per recruit were predicted at annual exploitation rates between 5 and 15%. Most characteristics of reservoir populations were less than or equal to optima reported for the unimpounded lower river; as a result, yield per recruit, reproductive potential per recruit, and the number of recruits were less in reservoirs than in the unimpounded river. Comparisons with pristine standing stocks suggest that the unimpounded river may approximate preimpoundment conditions for white sturgeon. We conclude that potential yield from impounded populations has been reduced by dam construction, which restricts populations to river segments that may not include conditions optimal for all life stages. Alternatives for enchancement of reservoir populations might include improved passage at dams, increased spring flow to improve spawning success, transplants from productive populations, hatchery supplementation, and more intensive harvest management. 54 refs., 7 figs., 7 tabs.

  15. The Australian lungfish (Neoceratodus forsteri) - fish or amphibian pattern of muscle development?

    PubMed

    Kacperczyk, Agata; Daczewska, Malgorzata

    2008-01-01

    The Australian lungfish Neoceratodus forsteri (Dipnoi-Sarcoterygians) is a likely candidate for the extant sister group of Tetrapoda. Transmission electron and light microscopy analysis revealed that the arrangement of somite cells of the lungfish resembles the structure of the urodelan somite. On the other hand, the pattern of early muscle formation in N. forsteri is similar to that found in the Siberian sturgeon (Acipenser baeri). During the early stages of myogenesis of N. forsteri, somite-derived cells fuse to form multinucleated muscle lamellae. During later stages, mononucleated undifferentiated cells are first observed in the intermyotomal fissures and subsequently in the myotomes, among white muscle lamellae. The cells from the intermyotomal fissure differentiate into fibroblasts. The cells which have migrated into the myotomes, differentiate into mesenchyme-derived myoblasts. After hatching, white muscle lamellae are successively converted into polygonal muscle fibres. Conversion of lamellae into fibres may occur through splitting of muscle lamellae, or cylindrical muscle fibres may arise de novo as a result of fusion of mesenchyme-derived myoblasts. No increase in the number of muscle fibre nuclei is observed either in embryonic or juvenile musculature of N. forsteri. We suggest that until the 53 stage of embryonic development, the increase in muscle mass is accomplished mainly through hyperplasy. Thus, lungfish muscle represents the organizational intermediate between fishes and amphibians. This makes it a useful model to study the evolutionary implications of the mechanisms of muscle development.

  16. Effects of propofol and carbon dioxide on acid-base balance in Siberian sturgeon.

    PubMed

    Gomułka, P; Czerniak, E; Dągowski, J; Łuczyński, M; Szczerbowski, A; Szkudlarek, M

    2015-01-01

    The aim of this study was to compare physiological responses in Siberian sturgeon (Acipenser baeri) induced by propofol and CO2 anaesthesia. Two procedures were applied during the experiment. In procedure I, blood samples were collected immediately after exposure (1, 2, 5, 10 min) to the anaesthetic. In procedure II, fish were exposed to the anaesthetic for 10 minutes and then were moved to anaesthetic free water. Blood was sampled after 5, 10, 20 or 30 min of recovery time. Gasometrical and biochemical analyses were performed on collected blood. In CO2 anaesthetized fish strong hypercapnic acidosis was revealed. The drop of the HCO3-/CO2 ratio, from 28:1 in control fish up to 4:1 in CO2 anaesthetized ones, proved that the compensation mechanism is not capable of preventing acidosis during CO2 anaesthesia in Siberian sturgeon. In contrast, only moderate, respiratory acidosis occurred in sturgeons anaesthetised with propofol. Hypercapnic acidosis during CO2 anaesthesia was followed by a fourfold increase of ammonia level in the blood. Glucose level, increasing only during recovery time, indicates that a secondary stress response occurred when awareness of anaesthetized fish had been restored.

  17. New genus and species of Aporocotylidae (Digenea) from a basal actinopterygian, the American paddlefish, Polyodon spathula, (Acipenseriformes: Polyodontidae) from the Mississippi Delta.

    PubMed

    Bullard, Stephen A; Snyder, Scott D; Jensen, Kirsten; Overstreet, Robin M

    2008-04-01

    Acipensericola petersoni n. gen., n. sp. (Digenea: Aporocotylidae) infects the heart of the American paddlefish Polyodon spathula (Walbaum, 1792) in the Mississippi Delta. It has robust, spike-like body spines arranged in ventrolateral transverse rows; a bowl-shaped anterior sucker centered on the mouth and having minute spines on the inner anteroventral surface only; a pharynx; an inverse U-shaped ceca extending to near the posterior body end; intercecal testes comprising a pre-ovarian testicular column plus a single testis posteriorly; an extensively lobed ovary located medially and immediately posterior to the testicular column; a spherical ootype that is intercecal and post-ovarian; a Laurer's canal; and a common genital pore. The new species is the first-named aporocotylid collected from a basal actinopterygian. It resembles the chondrichthyan aporocotylids Chimaerohemecus trondheimensis, Orchispirium heterovitellatum, and Hyperandrotrema cetorhini in having an inverse U-shaped ceca, but it is morphologically most similar to the anguilliform aporocotylid Paracardicoloides yamagutii in having that feature plus a comparable anterior sucker, a single testis posteriorly, an intertesticular ovary, and a common genital pore. Sequence data for the complete small subunit ribosomal DNA (18S) do not refute its membership within Aporocotylidae nor its affinity to 1 of those aforementioned aporocotylids: A. petersoni was basal to the few teleost aporocotylids analyzed, and C. trondheimensis was the only taxon basal to A. petersoni. We regard the specimens of Spirorchis sp. previously reported from the shortnose sturgeon Acipenser brevirostrum Lesueur, 1818 as congeneric with the new species.

  18. Species profiles: life histories and environmental requirements of coastal fishes and invertebrates (South Atlantic) - Atlantic sturgeon

    SciTech Connect

    Van Den Avyle, M.J.

    1984-07-01

    The Atlantic sturgeon, Acipenser oxyrhynchus oxyrhynchus, is an anadromous species that occupies rivers, estuaries, and nearshore waters along the entire Atlantic coast of the United States. The species once supported significant commercial fisheries throughout its range, but stocks have declined because of overfishing, deterioration of water quality, and damming of rivers. Atlantic sturgeon spawn in rivers and the young remain in freshwater for several years prior to emigration to the ocean. Little is known about spawning areas and associated environmental factors. Females typically do not mature until age X and the age at first spawning ranges from 5 to 13 years for males and 7 to 19 years for females. Longevity may frequently exceed 25 years. Immature and adult sturgeons are bottom feeders and consume a variety of mollusks, crustaceans, worms, and other small bottom-dwelling invertebrates and fishes. Little is know about competitors, predators, or effects of environmental factors on recruitment. The long period required to reach maturity, possibly irregular spawning thereafter, and prolonged reliance on river systems make juvenile and adult Atlantic sturgeon highly susceptible to habitat alterations, pollution, and over exploitation. 49 references, 2 figures, 4 tables.

  19. Lake sturgeon spawning on artificial habitat in the St Lawrence River

    USGS Publications Warehouse

    Johnson, J.H.; LaPan, S.R.; Klindt, R.M.; Schiavone, A.

    2006-01-01

    In 1996, lake sturgeon (Acipenser fulvescens) spawning was documented for the third consecutive year on an artificially placed gravel bed in the St Lawrence River. Two distinct spawning periods were observed in 1996. Spawning initially commenced on 17 June, when water temperature reached 15°C. A second spawning event was documented from 28 June to 1 July (16°C). Sturgeon egg densities were monitored in three transects on egg trays, on the gravel surface, and within interstitial spaces in the gravel. Counts of developing eggs in the gravel bed during both spawning periods were used to estimate a total of 275 000 eggs on the study area (0.075 ha). Average egg density was highest in the transect with the highest water velocities. Lake sturgeon fry were first observed in the gravel on 24 June (15.5°C), and first emergence from the gravel was documented on 28 June. Hatching following the second spawning event commenced on 3 July. Based on assessment of average embryo viability (61.6%) and egg-to-emergent fry survival (17.6%) an estimate of about 171 000 sturgeon eggs hatched, producing over 49 000 emergent fry. Current velocity, substrate particle size, depth of substrate, and maintenance of sediment-free interstitial spaces are important considerations in planning future spawning habitat enhancement projects.

  20. Resolving microsatellite genotype ambiguity in populations of allopolyploid and diploidized autopolyploid organisms using negative correlations between allelic variables.

    PubMed

    Clark, Lindsay V; Schreier, Andrea Drauch

    2016-11-21

    A major limitation in the analysis of genetic marker data from polyploid organisms is non-Mendelian segregation, particularly when a single marker yields allelic signals from multiple, independently segregating loci (isoloci). However, with markers such as microsatellites that detect more than two alleles, it is sometimes possible to deduce which alleles belong to which isoloci. Here, we describe a novel mathematical property of codominant marker data when it is recoded as binary (presence/absence) allelic variables: under random mating in an infinite population, two allelic variables will be negatively correlated if they belong to the same locus, but uncorrelated if they belong to different loci. We present an algorithm to take advantage of this mathematical property, sorting alleles into isoloci based on correlations, then refining the allele assignments after checking for consistency with individual genotypes. We demonstrate the utility of our method on simulated data, as well as a real microsatellite data set from a natural population of octoploid white sturgeon (Acipenser transmontanus). Our methodology is implemented in the R package polysat version 1.6.

  1. Modeling white sturgeon movement in a reservoir: The effect of water quality and sturgeon density

    USGS Publications Warehouse

    Sullivan, A.B.; Jager, H.I.; Myers, R.

    2003-01-01

    We developed a movement model to examine the distribution and survival of white sturgeon (Acipenser transmontanus) in a reservoir subject to large spatial and temporal variation in dissolved oxygen and temperature. Temperature and dissolved oxygen were simulated by a CE-QUAL-W2 model of Brownlee Reservoir, Idaho for a typical wet, normal, and dry hydrologic year. We compared current water quality conditions to scenarios with reduced nutrient inputs to the reservoir. White sturgeon habitat quality was modeled as a function of temperature, dissolved oxygen and, in some cases, suitability for foraging and depth. We assigned a quality index to each cell along the bottom of the reservoir. The model simulated two aspects of daily movement. Advective movement simulated the tendency for animals to move toward areas with high habitat quality, and diffusion simulated density dependent movement away from areas with high sturgeon density in areas with non-lethal habitat conditions. Mortality resulted when sturgeon were unable to leave areas with lethal temperature or dissolved oxygen conditions. Water quality was highest in winter and early spring and lowest in mid to late summer. Limiting nutrient inputs reduced the area of Brownlee Reservoir with lethal conditions for sturgeon and raised the average habitat suitability throughout the reservoir. Without movement, simulated white sturgeon survival ranged between 45 and 89%. Allowing movement raised the predicted survival of sturgeon under all conditions to above 90% as sturgeon avoided areas with low habitat quality. ?? 2003 Elsevier B.V. All rights reserved.

  2. Vulnerability of larval and juvenile white sturgeon to barotrauma: can they handle the pressure?

    PubMed Central

    Brown, Richard S.; Cook, Katrina V.; Pflugrath, Brett D.; Rozeboom, Latricia L.; Johnson, Rachelle C.; McLellan, Jason G.; Linley, Timothy J.; Gao, Yong; Baumgartner, Lee J.; Dowell, Frederick E.; Miller, Erin A.; White, Timothy A.

    2013-01-01

    Techniques were developed to determine which life stages of fish are vulnerable to barotrauma from expansion of internal gases during decompression. Eggs, larvae, and juvenile hatchery-reared white sturgeon (Acipenser transmontanus; up to 91 days post hatch; d.p.h.) were decompressed to assess vulnerability to barotrauma and identify initial swim bladder inflation. Barotrauma-related injury and mortality were first observed 9 d.p.h., on the same day as initial exogenous feeding. However, barotrauma-related injury did not occur again until swim bladder inflation 75 d.p.h. (visible at necropsy and on radiographs). Swim bladder inflation was not consistent among individuals, with only 44% being inflated 91 d.p.h. Additionally, swim bladder inflation did not appear to be size dependent among fish ranging in total length from 61 to 153 mm at 91 d.p.h. The use of a combination of decompression tests and radiography was validated as a method to determine initial swim bladder inflation and vulnerability to barotrauma. Extending these techniques to other species and life-history stages would help to determine the susceptibility of fish to hydro turbine passage and aid in fish conservation. PMID:27293603

  3. Efficacy of iodine for disinfection of Lake Sturgeon eggs from the St. Lawrence River, New York

    USGS Publications Warehouse

    Chalupnicki, Marc A.; Dittman, Dawn E.; Starliper, Clifford E.; Iwanowicz, Deborah

    2014-01-01

    Optimal fish husbandry to reduce the risk of disease is particularly important when using wild fish as the source for gametes. The propagation and reestablishment of Lake Sturgeon Acipenser fulvescens in New York waters to become a viable self-sustaining population is considered a high priority by managers. While standard hatchery egg disinfection practices have been used to prevent the transmission of diseases, data on the bacterial loads present on egg surfaces following iodine disinfection is lacking. Our study investigated the bacteria present on the outer surface of Lake Sturgeon eggs and the effectiveness of an iodine disinfection treatment in eliminating bacteria that could pose a threat to egg survival and cause hatchery disease outbreaks. During the springs of 2011–2013, 12 to 41 different species of bacteria were recovered from the outer egg surfaces prior to an iodine treatment; Aeromonas, Pseudomonas, Shewanella, and Chryseobacterium were the most common genera identified. Cohort eggs treated using the standard protocol of a single treatment of 50 mg/L iodine for 30 min resulted in an average of 57.8% reduction in bacterial CFU/g. While this is a significant reduction, bacteria were not completely eliminated and hatchery managers should be aware that pathogens could remain on Lake Sturgeon eggs following the standard iodine disinfection treatment.

  4. Status and Habitat Requirements of the White Sturgeon Populations in the Columbia River Downstream from McNary Dam, 1990-1991 Annual Report.

    SciTech Connect

    Nigro, Anthony A.

    1991-09-01

    We report on our effort from April 1990 to March 1991 to describe the life history and population dynamics of white sturgeon Acipenser transmontanus in.John Day Reservoir. We set 1188 set lines and 26 gill nets. We caught 623 white sturgeon with set lines and 236 with gill nets. Catch per unit effort was much higher in areas near the tailrace than in downstream sites. Our setlines were size selective. We recaptured 3 fish released in John Day Reservoir in 1989 and 28 fish released in 1990. Sport and commercial fishermen recovered 62 tags from fish we tagged in Bonneville, The Dalles and John Day reservoirs, 1987-1990. We observed extensive movements of marked sturgeon within the reservoirs. We completed aging of available samples from all three reservoirs from 1987-1990. We aged fish as old as 46 years. Bone marks were observed on 74 of 78 fish previously injected with oxytetracycline and annulus formation was generally complete after June. We estimated parameters in a length-weight equation. About 1.5% of the female white sturgeon we examined to date had early or late vitellogenic eggs and would be expected to spawn the following year.

  5. A model to locate potential areas for lake sturgeon spawning habitat construction in the St. Clair–Detroit River System

    USGS Publications Warehouse

    Bennion, David; Manny, Bruce A.

    2014-01-01

    In response to a need for objective scientific information that could be used to help remediate loss of fish spawning habitat in the St. Clair River and Detroit River International Areas of Concern, this paper summarizes a large-scale geographic mapping investigation. Our study integrates data on two variables that many riverine fishes respond to in selecting where to spawn in these waters (water flow velocity and water depth) with available maps of the St. Clair–Detroit River System (SC–DRS). Our objectives were to locate and map these two physical components of fish habitat in the St. Clair and Detroit rivers and Lake St. Clair using a geographic information system (GIS) and to identify where, theoretically, fish spawning habitat could be remediated in these rivers. The target fish species to which this model applies is lake sturgeon (Acipenser fulvescens), but spawning reefs constructed for lake sturgeon in this system have been used for spawning by 17 species of fish. Our analysis revealed areas in each river that possessed suitable water velocity and depth for fish spawning and therefore could theoretically be remediated by the addition of rock-rubble substrate like that used at two previously remediated sites in the Detroit River at Belle Isle and Fighting Island. Results of our analysis revealed that only 3% of the total area of the SC–DRS possesses the necessary combination of water depth and high flow velocity to be indicated by the model as potential spawning habitat for lake sturgeon.

  6. Status and Habitat Requirements of the White Sturgeon Populations in the Columbia River Downstream from McNary Dam Volume II; Supplemental Papers and Data Documentation, 1986-1992 Final Report.

    SciTech Connect

    Beamesderfer, Raymond C.; Nigro, Anthony A.

    1995-01-01

    This is the final report for research on white sturgeon Acipenser transmontanus from 1986--92 and conducted by the National Marine Fisheries Service (NMFS), Oregon Department of Fish and Wildlife (ODFW), US Fish and Wildlife Service (USFWS), and Washington Department of Fisheries (WDF). Findings are presented as a series of papers, each detailing objectives, methods, results, and conclusions for a portion of this research. This volume includes supplemental papers which provide background information needed to support results of the primary investigations addressed in Volume 1. This study addresses measure 903(e)(1) of the Northwest Power Planning Council's 1987 Fish and Wildlife Program that calls for ''research to determine the impact of development and operation of the hydropower system on sturgeon in the Columbia River Basin.'' Study objectives correspond to those of the ''White Sturgeon Research Program Implementation Plan'' developed by BPA and approved by the Northwest Power Planning Council in 1985. Work was conducted on the Columbia River from McNary Dam to the estuary.

  7. Structuring decisions for managing threatened and endangered species in a changing climate.

    PubMed

    Gregory, Robin; Arvai, Joseph; Gerber, Leah R

    2013-12-01

    The management of endangered species under climate change is a challenging and often controversial task that incorporates input from a variety of different environmental, economic, social, and political interests. Yet many listing and recovery decisions for endangered species unfold on an ad hoc basis without reference to decision-aiding approaches that can improve the quality of management choices. Unlike many treatments of this issue, which consider endangered species management a science-based problem, we suggest that a clear decision-making process is equally necessary. In the face of new threats due to climate change, managers' choices about endangered species require closely linked analyses and deliberations that identify key objectives and develop measurable attributes, generate and compare management alternatives, estimate expected consequences and key sources of uncertainty, and clarify trade-offs across different dimensions of value. Several recent cases of endangered species conservation decisions illustrate our proposed decision-focused approach, including Gulf of Maine Atlantic salmon (Salmo salar) recovery framework development, Cultus Lake sockeye salmon (Oncorhynchus nerka) management, and Upper Columbia River white sturgeon (Acipenser transmontanus) recovery planning. Estructuración de Decisiones para Manejar Especies Amenazadas y en Peligro en un Clima Cambiante.

  8. Assessment of aquatic organisms as bioindicators of historical radionuclide release to the Columbia River

    SciTech Connect

    Dauble, D.D.; Poston, T.M.; Newell, R.L.

    1988-12-01

    This study examined the potential for using several aquatic organisms as biological indicators of historic levels of radionuclides released to the Hanford Reach of the Columbia River. The purpose of the study was to determine the types of environmental samples that could be collected to further our understanding of previous releases of radionuclides at Hanford. Information was initially collected to determine the relative abundance and persistence of radionuclides historically released at Hanford. The potential for long-lived radionuclides to bioaccumulated in aquatic organisms was then assessed. The life history of several common aquatic organisms was examined to evaluate their use as potential bioindicators of radionuclides released to the Columbia River. Considerations for analyzing strontium (ZSr) in biological samples were determined. Based on our review of radionuclides released to the environment and their potential for bioaccumulation in aquatic organisms, strontium appears to be the only radionuclide suitable for further study. White sturgeon (Acipenser transmontanus) and the common mussel (Margaritifera margaritifera) are suitable candidates for developing dose reconstruction scenarios. Considerations for tissue analysis of radionuclide concentration in these species include potential for biological turnover and tissue mass. 48 refs., 1 fig., 4 tabs.

  9. Chemical contaminants and their effects in fish and wildlife from the industrial zone of Sumgayit, Republic of Azerbaijan.

    PubMed

    Swartz, Carol D; Donnelly, K C; Islamzadeh, Arif; Rowe, Gilbert T; Rogers, William J; Palatnikov, Grigoriy M; Mekhtiev, Arif A; Kasimov, Rafik; McDonald, Thomas J; Wickliffe, Jeffery K; Presley, Bobby J; Bickham, John W

    2003-12-01

    Sediment from a wetland adjacent to an industrial wastewater treatment plant in Sumgayit contained concentrations of total PAHs, total PCBs, aldrin, biphenyl, chlordane, DDT, mercury, beta-endosulfan, heptachlor, alpha-hexacyclohexane (alpha-HCH), gamma-HCH, and several individual PAH congeners that were elevated relative to published sediment quality guidelines. Chemical analyses of tissues from European pond turtles (Emys orbicularis) had increased levels of many of the same chemicals including aldrin, chlordane, heptachlor, alpha-HCH, total PCBs, total PAHs, and mercury, compared to reference turtles. In addition, turtle tissues contained elevated levels of DDD, hexachlorobenzene (HCB), and pentachlorobenzene that were not elevated in the sediment sample. Some differences were observed in contaminant levels between European pond turtles and Caspian turtles (Mauremys caspica) taken from the ponds in Sumgayit. Salmonella/microsome mutagenicity assays on pond sediments were negative or weakly positive. Micronuclei in European pond turtles were statistically correlated with tissue levels of mercury, heptachlor, DDD, HCB, and trans-nonachlor. Microcosm experiments using Russian sturgeon (Acipenser gueldenstaedtii) showed a positive dose-response relationship between exposure to suspended contaminated pond sediment and acute toxicity. Chemical and biological assays used in this study show the industrial area of Sumgayit is heavily contaminated with a complex mixture of toxic pollutants. Exposure to contaminated sediments produced acute effects in Russian sturgeon, but genotoxic effects appear to be slight.

  10. Migration and habitats of diadromous Danube River sturgeons in Romania: 1998-2000

    USGS Publications Warehouse

    Kynard, B.; Suciu, R.; Horgan, M.

    2002-01-01

    Upstream migrant adults of stellate sturgeon, Acipenser stellatus (10 in 1998, 43 in 1999) and Russian sturgeon, A. gueldenstaedtii (three in 1999) were captured at river km (rkm) 58-137, mostly in the spring, and tagged with acoustic tags offering a reward for return. The overharvest was revealed by tag returns (38% in 1998, 28% in 1999) and by harvest within 26 days (and before reaching spawning grounds) of the six stellate sturgeon tracked upstream. A drop-back of > 50% of the tagged sturgeon, some to the Black Sea, shows a high sensitivity to interruption of migration and capture/handling/holding. Harvesting and dropback prevented tracking of sturgeon to spawning sites. Gillnetting and tracking of stellate sturgeon showed that the autumn migration ended in early October (river temperature 16??C) and identified a likely wintering area at river km (rkm) 75-76 (St George Branch). Thus, fishery harvesting after early October captures wintering fish, not migrants. Rare shoreline cliffs in the lower river likely create the only rocky habitat for sturgeon spawning. A survey for potential spawning habitats found five sites with rocky substrate and moderate water velocity, all ???rkm 258. Drift netting caught early life-stages of 17 fish species and one sturgeon, a beluga, Huso huso, larva likely spawned at ???rkm 258. All diadromous Danube sturgeons likely spawn at ???rkm 258.

  11. Important Considerations for Methemoglobin Measurement in Fish Blood: Assay Choice and Storage Conditions

    SciTech Connect

    Kuntz, Mel Anton; Rodnick, K. J.; J. A. Lacey

    2002-05-01

    Spectrophotometric assays of methaemoglobin (metHb) in rainbow trout Oncorhynchus mykiss, channel catfish Ictalurus punctatus, tilapias Tilapia niloticus and Tilapia zillii and white sturgeon Acipenser transmontanus, under baseline conditions, were low (<4%) for each species, and yet higher than human values (<1%). MetHb results for a given fish species varied significantly between assays and two assays were deemed unacceptable for particular animals. For rainbow trout, white sturgeon, and the two species of tilapia, the Dubowski method gave uncharacteristically high estimates of metHb. MetHb could not measured in tilapia blood using the Evelyn & Malloy method due to spectral interference. Only the Horecker & Brackett assay worked well for all species. Storage conditions were extremely important in the quantification of metHb in rainbow trout blood. For consistent values, samples can be stored up to 4 h on ice (0 degrees C) or at least 20 days under liquid nitrogen (-196 degrees C). Auto-oxidation, however, elevates rainbow trout metHb at -20 and -80 degrees C. It should not be assumed that the blood of fishes and humans perform similarly during assays of metHb.

  12. The elusive minimum viable population size for white sturgeon

    SciTech Connect

    Jager, Yetta; Lepla, Ken B.; Van Winkle, Webb; James, Mr Brad; McAdam, Dr Steve

    2010-01-01

    Biological conservation of sturgeon populations is a concern for many species. Those responsible for managing the white sturgeon (Acipenser transmontanus) and similar species are interested in identifying extinction thresholds to avoid. Two thresholds that exist in theory are the minimum viable population size (MVP) and minimum amount of suitable habitat. In this paper, we present both model and empirical estimates of these thresholds. We modified a population viability analysis (PVA) model for white sturgeon to include two new Allee mechanisms. Despite this, PVA-based MVP estimates were unrealistically low compared with empirical estimates unless opportunities for spawning were assumed to be less frequent. PVA results revealed a trade-off between MVP and habitat thresholds; smaller populations persisted in longer river segments and vice versa. Our empirical analyses suggested (1) a MVP range based on population trends from 1,194 to 27,700 individuals, and (2) a MVP estimate of 4,000 individuals based on recruitment. Long-term historical population surveys are needed for more populations to pinpoint an MVP based on trends, whereas the available data were sufficient to estimate MVP based on recruitment. Beyond the MVP, we developed a hierarchical model for population status based on empirical data. Metapopulation support was the most important predictor of population health, followed by the length of free-flowing habitat, with habitat thresholds at 26 and 150 km. Together, these results suggest that habitat and connectivity are important determinants of population status that likely influence the site-specific MVP thresholds.

  13. Quantifying Fish Swimming Behavior in Response to Acute Exposure of Aqueous Copper Using Computer Assisted Video and Digital Image Analysis

    PubMed Central

    Calfee, Robin D.; Puglis, Holly J.; Little, Edward E.; Brumbaugh, William G.; Mebane, Christopher A.

    2016-01-01

    Behavioral responses of aquatic organisms to environmental contaminants can be precursors of other effects such as survival, growth, or reproduction. However, these responses may be subtle, and measurement can be challenging. Using juvenile white sturgeon (Acipenser transmontanus) with copper exposures, this paper illustrates techniques used for quantifying behavioral responses using computer assisted video and digital image analysis. In previous studies severe impairments in swimming behavior were observed among early life stage white sturgeon during acute and chronic exposures to copper. Sturgeon behavior was rapidly impaired and to the extent that survival in the field would be jeopardized, as fish would be swept downstream, or readily captured by predators. The objectives of this investigation were to illustrate protocols to quantify swimming activity during a series of acute copper exposures to determine time to effect during early lifestage development, and to understand the significance of these responses relative to survival of these vulnerable early lifestage fish. With mortality being on a time continuum, determining when copper first affects swimming ability helps us to understand the implications for population level effects. The techniques used are readily adaptable to experimental designs with other organisms and stressors. PMID:26967350

  14. Genetic effects of habitat restoration in the Laurentian Great Lakes: an assessment of lake sturgeon origin and genetic diversity

    USGS Publications Warehouse

    Jamie Marie Marranca,; Amy Welsh,; Roseman, Edward F.

    2015-01-01

    Lake sturgeon (Acipenser fulvescens) have experienced significant habitat loss, resulting in reduced population sizes. Three artificial reefs were built in the Huron-Erie corridor in the Great Lakes to replace lost spawning habitat. Genetic data were collected to determine the source and numbers of adult lake sturgeon spawning on the reefs and to determine if the founder effect resulted in reduced genetic diversity. DNA was extracted from larval tail clips and 12 microsatellite loci were amplified. Larval genotypes were then compared to 22 previously studied spawning lake sturgeon populations in the Great Lakes to determine the source of the parental population. The effective number of breeders (Nb) was calculated for each reef cohort. The larval genotypes were then compared to the source population to determine if there were any losses in genetic diversity that are indicative of the founder effect. The St. Clair and Detroit River adult populations were found to be the source parental population for the larvae collected on all three artificial reefs. There were large numbers of contributing adults relative to the number of sampled larvae. There was no significant difference between levels of genetic diversity in the source population and larval samples from the artificial reefs; however, there is some evidence for a genetic bottleneck in the reef populations likely due to the founder effect. Habitat restoration in the Huron-Erie corridor is likely resulting in increased habitat for the large lake sturgeon population in the system and in maintenance of the population's genetic diversity.

  15. Lake sturgeon population characteristics in Rainy Lake, Minnesota and Ontario

    USGS Publications Warehouse

    Adams, W.E.; Kallemeyn, L.W.; Willis, D.W.

    2006-01-01

    Rainy Lake contains a native population of lake sturgeon Acipenser fulvescens that has been largely unstudied. The aims of this study were to document the population characteristics of lake sturgeon in Rainy Lake and to relate environmental factors to year-class strength for this population. Gill-netting efforts throughout the study resulted in the capture of 322 lake sturgeon, including 50 recaptures. Lake sturgeon in Rainy Lake was relatively plump and fast growing compared with a 32-population summary. Population samples were dominated by lake sturgeon between 110 and 150 cm total length. Age–structure analysis of the samples indicated few younger (<10 years) lake sturgeon, but the smallest gill net mesh size used for sampling was 102 mm (bar measure) and would not retain small sturgeon. Few lake sturgeon older than age 50 years were captured, and maximum age of sampled fish was 59 years. Few correlations existed between lake sturgeon year-class indices and both annual and monthly climate variables, except that mean June air temperature was positively correlated with year-class strength. Analysis of Rainy Lake water elevation and resulting lake sturgeon year-class strength indices across years yielded consistent but weak negative correlations between late April and early June, when spawning of lake sturgeon occurs. The baseline data collected in this study should allow Rainy Lake biologists to establish more specific research questions in the future.

  16. Shortnose sturgeon use small coastal rivers: The importance of habitat connectivity

    USGS Publications Warehouse

    Zydlewski, G.B.; Kinnison, M.T.; Dionne, P.E.; Zydlewski, J.; Wippelhauser, G.S.

    2011-01-01

    Contrary to conventional wisdom for shortnose sturgeon (Acipenser brevirostrum), we document shortnose sturgeon use of habitats beyond large rivers. Telemetry data from 2008 to 2010 in the Gulf of Maine demonstrates that adult shortnose sturgeon (up to 70%) frequently move between Maine's two largest rivers, the Kennebec and Penobscot Rivers. Even more interesting, small rivers located between these watersheds were used by 52% of the coastal migrants. Small river use was not trivial, 80% of observed movements extended more than 10km upstream. However, visits were short in duration. This pattern indicates one of several possibilities: directed use of resources, searching behaviors related to reproduction (i.e. straying) or undirected wandering. Data suggest a relationship between residence time in small rivers and distance to the lowermost barrier. Restoring connectivity to upstream habitats in these rivers could allow opportunities for metapopulation expansion. Regional management of shortnose sturgeon in the Gulf of Maine should incorporate a habitat framework that considers small coastal rivers. ?? 2011 Blackwell Verlag, Berlin.

  17. Practical application of electromyogram radiotelemetry: the suitability of applying laboratory-acquired calibration data to field data

    SciTech Connect

    Geist, David R. ); Brown, Richard S.; Lepla, Ken; Chandler, James P.

    2001-12-01

    One of the practical problems with quantifying the amount of energy used by fish implanted with electromyogram (EMG) radio transmitters is that the signals emitted by the transmitter provide only a relative index of activity unless they are calibrated to the swimming speed of the fish. Ideally calibration would be conducted for each fish before it is released, but this is often not possible and calibration curves derived from more than one fish are used to interpret EMG signals from individuals which have not been calibrated. We tested the validity of this approach by comparing EMG data within three groups of three wild juvenile white sturgeon Acipenser transmontanus implanted with the same EMG radio transmitter. We also tested an additional six fish which were implanted with separate EMG transmitters. Within each group, a single EMG radio transmitter usually did not produce similar results in different fish. Grouping EMG signals among fish produced less accurate results than having individual EMG-swim speed relationships for each fish. It is unknown whether these differences were a result of different swimming performances among individual fish or inconsistencies in the placement or function of the EMG transmitters. In either case, our results suggest that caution should be used when applying calibration curves from one group of fish to another group of uncalibrated fish.

  18. Variation in large-bodied fish-community structure and abundance in relation to water-management regime in a large regulated river.

    PubMed

    Haxton, T J; Findlay, C S

    2009-07-01

    Variation in life-history traits (growth, condition, mortality and recruitment) and relative abundance of 11 large-bodied fish species was investigated among three water-management regimes (unimpounded, run-of-the-river and winter reservoirs) in the large regulated Ottawa River, Canada. If waterpower management had an effect on fishes, then (1) would be expected community structuring among water-management regimes and (2) species with similar life-history traits should be affected in a similar manner. Large-bodied fish communities were assessed using two different standard index-netting techniques, one using trap nets and the other gillnets. Community structure could be discriminated based on species caught in nets using holographic neural networks (78.8% correct overall classification rate using trap nets and 76.0% using gillnets); therefore, water-management regimes affected community structure in the Ottawa River. Littoral zone benthivores were significantly lower in abundance (P < 0.001) or absent in winter reservoirs, whereas the abundance of planktivores or species that were planktivorous at young ages were significantly greater than in unimpounded river reaches. Growth, condition and mortality did not vary among reach types except smallmouth bass Micropterus dolomieu were in better condition in winter reservoirs than unimpounded reaches. Lake sturgeon Acipenser fulvescens recruitment was impaired in run-of-the-river reaches, whereas recruitment for other species that spawn in fast water was not affected.

  19. Assigning sex and reproductive stage to adult Lake Sturgeon using ultrasonography and common morphological measurements

    USGS Publications Warehouse

    Chiotti, Justin A.; Boase, James C.; Hondorp, Darryl W.; Briggs, Andrew S.

    2016-01-01

    Sex determination of fish species is difficult to assess when sexual dimorphism and gametes are not apparent. For threatened and endangered fish species, noninvasive techniques are needed when determining sex to minimize stress and the potential for mortality. We evaluated the use of a portable ultrasound unit to determine sex of Lake Sturgeon Acipenser fulvescens in the field. Ultrasound images were collected from 9 yellow-egg (F2, F3), 32 black-egg (F4, F5), and 107 fully developed male (M2) Lake Sturgeon. Two readers accurately assigned sex to 88–96% of fish, but accuracy varied in relation to maturity stage. Black-egg females and fully developed males were correctly identified for 89–100% of the fish sampled, while these two readers identified yellow-egg females only 33% and 67% of the time. Time spent collecting images ranged between 2 and 3 min once the user was comfortable with operating procedures. Discriminant analysis revealed the total length : girth ratio was a strong predictor of sex and maturity, correctly classifying 81% of black-egg females and 97% of the fully developed males. However, yellow-egg females were incorrectly classified on all occasions. This study shows the utility of using ultrasonography and a total length : girth ratio for sex determination of Lake Sturgeon in later reproductive stages around the spawning season.

  20. Salinity effects on activity and expression of glutathione S-transferases in white sturgeon and Chinook salmon.

    PubMed

    Donham, Rachel T; Morin, Dexter; Tjeerdema, Ronald S

    2006-02-01

    This study evaluated the activity and expression of the glutathione S-transferase (GST) detoxification isoenzymes in juvenile white sturgeon (Acipenser transmontanus) and Chinook salmon (Oncorhynchus tshawytscha) during acclimation from freshwater (2 per thousand) to estuarine (15 per thousand) salinity conditions. In white sturgeon, GST activity toward 1-chloro-2,4-dinitrobenzene (CDNB) increased significantly (P = 0.005; n = 5) with elevated salinity, but not for the Chinook salmon (P = 0.174; n = 10). GST activity of both sturgeon and salmon toward ethacrynic acid (ETHA) did not significantly change with elevated salinity (P = 0.516 with n = 3, and P = 0.125 with n = 3, respectively). Expression of the GST classes, and hepatic glutathione (GSH) concentration, as determined by HPLC, also did not significantly change with increased salinity. In conclusion, overall GST activity in white sturgeon, but not Chinook salmon, is stimulated by elevated water salinity, thus electrophilic chemicals such as pesticides may be more effectively detoxified by sturgeon as they undergo seaward migration.

  1. Vulnerability of larval and juvenile white sturgeon to barotrauma: can they handle the pressure?

    PubMed

    Brown, Richard S; Cook, Katrina V; Pflugrath, Brett D; Rozeboom, Latricia L; Johnson, Rachelle C; McLellan, Jason G; Linley, Timothy J; Gao, Yong; Baumgartner, Lee J; Dowell, Frederick E; Miller, Erin A; White, Timothy A

    2013-01-01

    Techniques were developed to determine which life stages of fish are vulnerable to barotrauma from expansion of internal gases during decompression. Eggs, larvae, and juvenile hatchery-reared white sturgeon (Acipenser transmontanus; up to 91 days post hatch; d.p.h.) were decompressed to assess vulnerability to barotrauma and identify initial swim bladder inflation. Barotrauma-related injury and mortality were first observed 9 d.p.h., on the same day as initial exogenous feeding. However, barotrauma-related injury did not occur again until swim bladder inflation 75 d.p.h. (visible at necropsy and on radiographs). Swim bladder inflation was not consistent among individuals, with only 44% being inflated 91 d.p.h. Additionally, swim bladder inflation did not appear to be size dependent among fish ranging in total length from 61 to 153 mm at 91 d.p.h. The use of a combination of decompression tests and radiography was validated as a method to determine initial swim bladder inflation and vulnerability to barotrauma. Extending these techniques to other species and life-history stages would help to determine the susceptibility of fish to hydro turbine passage and aid in fish conservation.

  2. Velocity estimation using a Bayesian network in a critical-habitat reach of the Kootenai River, Idaho

    NASA Astrophysics Data System (ADS)

    Palmsten, Margaret L.; Todd Holland, K.; Plant, Nathaniel G.

    2013-09-01

    Numerous numerical modeling studies have been completed in support of an extensive recovery program for the endangered white sturgeon (Acipenser transmontanus) on the Kootenai River near Bonner's Ferry, ID. A technical hurdle in the interpretation of these model results is the transfer of information from the specialist to nonspecialist such that practical decisions utilizing the numerical simulations can be made. To address this, we designed and trained a Bayesian network to provide probabilistic prediction of depth-averaged velocity. Prediction of this critical parameter governing suitable spawning habitat was obtained by exploiting the dynamic relationships between variables derived from model simulations with associated parameter uncertainties. Postdesign assessment indicates that the most influential environmental variables in order of importance are river discharge, depth, and width, and water surface slope. We demonstrate that the probabilistic network not only reproduces the training data with accuracy similar to the accuracy of a numerical model (root-mean-squared error of 0.10 m/s), but that it makes reliable predictions on the same river at times and locations other than where the network was trained (root mean squared error of 0.09 m/s). Additionally, the network showed similar skill (root mean square error of 0.04 m/s) when predicting velocity on the Apalachicola River, FL, a river of similar shape and size to the Kootenai River where a related sturgeon population is also threatened.

  3. Partial genome analysis of Siberian sturgeon alloherpesvirus suggests its close relation to AciHV-2 - short communication.

    PubMed

    Doszpoly, Andor; Shchelkunov, Igor S

    2010-06-01

    Partial genome sequence of a herpes-like virus, isolated from Siberian sturgeon (Acipenser baeri), was determined and subjected to phylogenetic analysis. The virus (SbSHV) has been shown to be the causative agent of an acute disease with high mortality in farmed juvenile sturgeons in Russia. Two fragments (of 7000 and 300 base pairs in length) encompassing 3 complete and 3 partial ORFs were amplified by PCR. Sturgeon herpesvirus strains, classified into species Acipenserid herpesvirus 2 (AciHV-2), have been isolated and partially sequenced from several regions (California, Idaho, Oregon and Canada) of North America from white (A. transmontanus) and shortnose sturgeons (A. brevirostrum). The sequence of the SbSHV strain shared highest identity with that of the Canadian strain originating from shortnose sturgeon. The phylogenetic analysis also confirmed that SbSHV is closely related to AciHV-2 and could also be classified into this virus species. This is the first report on the occurrence of AciHV-2 in Europe. Previously, only another virus species, AciHV-1 has been detected in farmed white sturgeons in Italy. The size and position of ORFs in the examined gene block confirmed that this genomic region is highly conserved in members of the genus Ictalurivirus.

  4. Selenium absorption, distribution, and excretion in white sturgeon orally dosed with l-selenomethionine.

    PubMed

    Tashjian, Diran H; Hung, Silas S O

    2006-10-01

    The usefulness of a newly developed, combined technique consisting of esophageal intubation, dorsal aortic cannulation, and urinary catheterization to deliver Se orally and to monitor Se uptake, accumulation, and excretion in white sturgeon (Acipenser transmontanus) was explored. Groups of five yearling sturgeon (1-2 kg) each were intubated with 0 (sham), 250, 500, or 1,000 microg Se/kg body weight in the form of L-selenomethionine, an ecologically relevant organic form of Se. Selenium concentrations in whole blood, plasma, and red blood cells did not change in the sham group but began to rise within 2 h postintubation in the other groups, and levels remained near maximum concentrations throughout the 48-h sampling period. Average urinary Se excretion rates over the entire 48-h period were 0.05, 0.46, 0.61, and 2.15 microg Se/kg/h in sturgeon intubated with 0, 250, 500, and 1,000 microg Se/kg, respectively. Selenium excretion rates were highest within the first 6 h in all treatment groups except the sham group. Selenium concentrations in the liver were positively correlated with the intubated Se dosage.

  5. New disease records for hatchery-reared sturgeon. II. Phaeohyphomycosis due to Veronaea botryosa.

    PubMed

    Steckler, Natalie K; Yanong, Roy P E; Pouder, Deborah B; Nyaoke, Akinyi; Sutton, Deanna A; Lindner, Jonathan R; Wickes, Brian L; Frasca, Salvatore; Wolf, Jeffrey C; Waltzek, Thomas B

    2014-10-16

    A series of fungal cases in hatchery-reared juvenile and young adult Siberian sturgeon Acipenser baerii and white sturgeon A. transmontanus occurred at production facilities in Florida and California, USA, respectively. Affected fish exhibited abnormal orientation and/or buoyancy, emaciation, coelomic distension, exophthalmos, cutaneous erythema, and ulcerative skin and eye lesions. Necropsies revealed haemorrhage throughout the coelom, serosanguinous coelomic effusion and organomegaly with nodular or cystic lesions in multiple organs. Fungal hyphae were observed in 27 fish (24 A. baerii and 3 A. transmontanus) via microscopic examination of tissue wet mounts and on slides prepared from colonies grown on culture media. Histopathological examination of these infected tissues revealed extensive infiltration by melanised fungal hyphae that were recovered in culture. Phenotypic characteristics and sequencing of the fungal isolates with the use of the internal transcribed spacer region and 28S rRNA gene confirmed the aetiological agent as Veronaea botryosa. To our knowledge, this is the first documentation of V. botryosa infection in fish, although melanised fungi of the closely related genus Exophiala are well-known pathogens of freshwater and marine fishes.

  6. The metabolic effects of prolonged starvation and refeeding in sturgeon and rainbow trout.

    PubMed

    Furné, Miriam; Morales, Amalia E; Trenzado, Cristina E; García-Gallego, Manuel; Carmen Hidalgo, M; Domezain, Alberto; Sanz Rus, Ana

    2012-01-01

    The present study examines the particular metabolic strategies of the sturgeon Acipenser naccarii in facing a period of prolonged starvation (72 days) and subsequent refeeding (60 days) compared to the trout Oncorhynchus mykiss response under similar conditions. Plasma metabolites, endogenous reserves, and the activity of intermediate enzymes in liver and white muscle were evaluated. This study shows the mobilization of tissue reserves during a starvation period in both species with an associated enzymatic response. The sturgeon displayed an early increase in hepatic glycolysis during starvation. The trout preferentially used lactate for gluconeogenesis in liver and white muscle. The sturgeon had higher lipid-degradation capacity and greater synthesis of hepatic ketone bodies than the trout, although this latter species also showed strong synthesis of ketone bodies during starvation. During refeeding, the metabolic activity present before starvation was recovered in both fish, with a reestablishment of tissue reserves, plasmatic parameters (glucemia and cholesterol), and enzymatic activities in the liver and muscle. A compensatory effect in enzymes regarding lipids, ketone bodies, and oxidative metabolism was displayed in the liver of both species. There are metabolic differences between sturgeon and trout that support the contention that the sturgeon has common characteristics with elasmobranchs and teleosts.

  7. High Conservation in Transcriptomic and Proteomic Response of White Sturgeon to Equipotent Concentrations of 2,3,7,8-TCDD, PCB 77, and Benzo[a]pyrene.

    PubMed

    Doering, Jon A; Tang, Song; Peng, Hui; Eisner, Bryanna K; Sun, Jianxian; Giesy, John P; Wiseman, Steve; Hecker, Markus

    2016-05-03

    Adverse effects associated with exposure to dioxin-like compounds (DLCs) are mediated primarily through activation of the aryl hydrocarbon receptor (AHR). However, little is known about the cascades of events that link activation of the AHR to apical adverse effects. Therefore, this study used high-throughput, next-generation molecular tools to investigate similarities and differences in whole transcriptome and whole proteome responses to equipotent concentrations of three agonists of the AHR, 2,3,7,8-TCDD, PCB 77, and benzo[a]pyrene, in livers of a nonmodel fish, the white sturgeon (Acipenser transmontanus). A total of 926 and 658 unique transcripts were up- and down-regulated, respectively, by one or more of the three chemicals. Of the transcripts shared by responses to all three chemicals, 85% of up-regulated transcripts and 75% of down-regulated transcripts had the same magnitude of response. A total of 290 and 110 unique proteins were up- and down-regulated, respectively, by one or more of the three chemicals. Of the proteins shared by responses to all three chemicals, 70% of up-regulated proteins and 48% of down-regulated proteins had the same magnitude of response. Among treatments there was 68% similarity between the global transcriptome and global proteome. Pathway analysis revealed that perturbed physiological processes were indistinguishable between equipotent concentrations of the three chemicals. The results of this study contribute toward more completely describing adverse outcome pathways associated with activation of the AHR.

  8. Evaluation of the toxicity and efficacy of hydrogen peroxide treatments on eggs of warm and cool water fishes

    USGS Publications Warehouse

    Rach, J.J.; Gaikowski, M.P.; Howe, G.E.; Schreier, T.M.

    1998-01-01

    The use of hydrogen peroxide in aquaculture is growing and there is a need to develop fundamental guidelines to effectively treat diseased fish. The safety (toxicity) of hydrogen peroxide treatments was determined on eggs of representative warm- and coolwater fish species. Eggs of northern pike (Esox lucius), walleye (Stizostedion vitreum), yellow perch (Pel ca flavescens), white sucker (Catostomus commersoni), lake sturgeon (Acipenser fulvescens), paddlefish (Polyodon spathula), common carp (Cyprinus carpio), and channel catfish (Ictalurus punctatus) were cultured in egg jars or aquaria. Treatments were initiated with non-eyed eggs and continued until all viable eggs had hatched. Eggs were treated daily for 15 min Monday through Friday with either 0, 500, 1000, 3000, or 6000 mu l l(-1) of hydrogen peroxide. For all species, the mean percent hatch was greater in eggs treated with 1000 mu l l(-1) hydrogen peroxide for 15 min than in the untreated controls. Common carp, lake sturgeon, and paddlefish were the least sensitive to hydrogen peroxide with percent hatch ranging from 40 to 48% in the 6000 mu l l(-1) hydrogen peroxide treatment. Fungal infections reduced or eliminated the hatch in most controls whereas nearly all treated eggs remained free of infection; hydrogen peroxide inhibited fungal infections on fish eggs. (C) 1998 Elsevier Science B.V. All rights reserved.

  9. An ecological basis for future fish habitat restoration efforts in the Huron-Erie Corridor

    USGS Publications Warehouse

    Hondorp, Darryl W.; Roseman, Edward F.; Manny, Bruce A.

    2014-01-01

    This perspective describes the major natural and anthropogenic forces driving change in the abundance and quality of fish habitats in the Huron-Erie Corridor (HEC), the Great Lakes connecting channel comprised of the St. Clair River, the Lake St. Clair, and the Detroit River. Channels connecting the Laurentian Great Lakes discharge large volumes of water equal to or greater than most other large rivers in the world that is of consistent high quality and volume, all year. Owing to creation of the St. Lawrence Seaway through the Great Lakes, the connecting channels have been modified by dredging over 200 km of deep-draft shipping lanes with a maintained depth of no less than 8.2 m. Combined with modification of their shorelines for housing and industries, use of the connecting channels for discharges of industrial and municipal wastes and shipping has resulted in numerous beneficial use impairments, such as restrictions on fish and wildlife consumption, degradation of fish and wildlife populations, and losses of fish and wildlife habitat. Various options for remediation of native fish populations and their habitats in the Great Lakes connecting channels, including construction of spawning habitat for threatened and high-value food fishes, such as lake sturgeon (Acipenser fulvescens), walleye (Sander vitreus), and lake whitefish (Coregonus clupeaformis), have been implemented successfully in two of the channels, and form the basis for further recommended research described in this article.

  10. Vulnerability of larval and juvenile white sturgeon to barotrauma: can they handle the pressure?

    SciTech Connect

    Brown, Richard S.; Cook, Katrina V.; Pflugrath, Brett D.; Rozeboom, Latricia L.; Johnson, Rachelle C.; McLellan, Jason; Linley, Timothy J.; Gao, Yong; Baumgartner, Lee J.; Dowell, Frederick E.; Miller, Erin A.; White, Timothy A.

    2013-07-01

    Techniques were developed to determine which life stages of fish are vulnerable to barotrauma from expansion of internal gases during decompression. Eggs, larvae and juvenile hatchery-reared white sturgeon (Acipenser transmontanus; up to 91 days post hatch; dph), were decompressed to assess vulnerability to barotrauma and identify initial swim bladder inflation. Barotrauma related injury and mortality were first observed 9 dph, on the same day as initial exogenous feeding. However, barotrauma related injury did not occur again until swim bladder inflation 75 dph (visible from necropsy and x-ray radiographs). Swim bladder inflation was not consistent among individuals, with only 44% being inflated 91 dph. Additionally, swim bladder inflation did not appear to be size dependent among fish ranging in total length from 61-153 mm at 91 dph. The use of a combination of decompression tests and x-ray radiography was validated as a method to determine initial swim bladder inflation and vulnerability to barotrauma. Extending these techniques to other species and life history stages would help to determine fish susceptibility to hydroturbine passage and aid in fish conservation.

  11. Commercial fish species of inland waters: a model for sustainability assessment and management.

    PubMed

    Simić, Vladica M; Simić, Snežana B; Stojković Piperac, Milica; Petrović, Ana; Milošević, Djuradj

    2014-11-01

    The permanent increase in the exploitation of commercial fish species has led to the need for developing practical and effective tools for the sustainability assessment and management of the target fish populations. The aim of this study was to formulate an ESHIPPOfishing model which would provide a reliable assessment of commercial fish population sustainability and indicate the conservation priorities. The existing ESHIPPO model was modified by introducing a new Index of local sustainability of fish populations (ILSFP) which enables the selection of "keystone populations" and "keystone habitats/ecosystems" within the basin being investigated. We employed a self-organizing map (SOM) in order to visualize the spatial distribution of the keystone populations and keystone habitats/ecosystems for each fish species. Based on the ILSFP values, environmental specialization (ES) of a fish species and local environmental factors (HIPPO factors), the model estimates the degree of sustainability (DS) of commercial fish populations in the freshwater ecosystems of the western Balkan Peninsula. The results indicate a low degree of sustainability for the majority of commercial fish species of the Middle Danube Basin, especially Acipenser ruthenus and Hucho hucho. The ESHIPPOfishing model presents a cost effective conservation approach, formulated to be applicable to any kind of river basin. The application of the ESHIPPOfishing model provides a comprehensive insight into the viability of target fish populations, which would not only further improve the selection of conservation priorities, but also facilitate the management of aquatic ecosystems.

  12. Importance of mechanics and kinematics in determining the stiffness contribution of the vertebral column during body-caudal-fin swimming in fishes.

    PubMed

    Nowroozi, Bryan N; Brainerd, Elizabeth L

    2014-02-01

    Whole-body stiffness in fishes has important consequences for swimming mode, speed and efficiency, but the contribution of vertebral column stiffness to whole-body stiffness is unclear. In our opinion, this lack of clarity is due in part to the lack of studies that have measured both in vitro mechanical properties of the vertebral column as well as in vivo vertebral kinematics in the same species. Some lack of clarity may also come from real variation in the mechanical role of the vertebral column across species. Previous studies, based on either mechanics or kinematics alone, suggest species-specific variation in vertebral column locomotor function that ranges from highly stiff regimes that contribute greatly to whole-body stiffness, and potentially act as a spring, to highly compliant regimes that only prohibit excessive flexion of the intervertebral joints. We review data collected in combined investigations of both mechanics and kinematics of three species, Myxine glutinosa, Acipenser transmontanus, and Morone saxatilis, to illustrate how mechanical testing within the context of the in vivo kinematics more clearly distinguishes the role of the vertebral column in each species. In addition, we identify species for which kinematic data are available, but mechanical data are lacking. We encourage further investigation of these species to fill these mechanical data gaps. Finally, we hope these future combined analyses will identify certain morphological, mechanical, or kinematic parameters that might be associated with certain vertebral column functional regimes with respect to body stiffness.

  13. Anatomy and early development of the pectoral girdle, fin, and fin spine of sturgeons (Actinopterygii: Acipenseridae).

    PubMed

    Dillman, Casey B; Hilton, Eric J

    2015-03-01

    Acipenseriformes hold an important place in the evolutionary history of bony fishes. Given their phylogenetic position as extant basal Actinopterygii, it is generally held that a thorough understanding of their morphology will greatly contribute to the knowledge of the evolutionary history and the origin of diversity for the major osteichthyan clades. To this end, we examined comparative developmental series from the pectoral girdle in Acipenser fulvescens, A. medirostris, A. transmontanus, and Scaphirhynchus albus to document, describe, and compare ontogenetic and allometric differences in the pectoral girdle. We find, not surprisingly, broad congruence between taxa in the basic pattern of development of the dermal and chondral elements of the pectoral girdle. However, we also find clear differences in the details of structure and development among the species examined in the dermal elements, including the clavicle, cleithrum, supracleithrum, posttemporal, and pectoral-fin spine. We also find differences in the internal fin elements such as the distal radials as well as in the number of fin rays and their association with the propterygium. Further, there are clear ontogenetic differences during development of the dermal and chondral elements in these species and allometric variation in the pectoral-fin spine. The characters highlighted provide a suite of elements for further examination in studies of the phylogeny of sturgeons. Determining the distribution of these characters in other sturgeons may aid in further resolution of phylogenetic relationships, and these data highlight the role that ontogenetic and comparative developmental studies provide in systematics.

  14. Adaption of egg and larvae sampling techniques for lake sturgeon and broadcast spawning fishes in a deep river

    USGS Publications Warehouse

    Roseman, E.F.; Boase, J.; Kennedy, G.; Craig, J.; Soper, K.

    2011-01-01

    In this report we describe how we adapted two techniques for sampling lake sturgeon (Acipenser fulvescens) and other fish early life history stages to meet our research needs in the Detroit River, a deep, flowing Great Lakes connecting channel. First, we developed a buoy-less method for sampling fish eggs and spawning activity using egg mats deployed on the river bottom. The buoy-less method allowed us to fish gear in areas frequented by boaters and recreational anglers, thus eliminating surface obstructions that interfered with recreational and boating activities. The buoy-less method also reduced gear loss due to drift when masses of floating aquatic vegetation would accumulate on buoys and lines, increasing the drag on the gear and pulling it downstream. Second, we adapted a D-frame drift net system formerly employed in shallow streams to assess larval lake sturgeon dispersal for use in the deeper (>8m) Detroit River using an anchor and buoy system. ?? 2011 Blackwell Verlag, Berlin.

  15. Quantifying fish swimming behavior in response to acute exposure of aqueous copper using computer assisted video and digital image analysis

    USGS Publications Warehouse

    Calfee, Robin D.; Puglis, Holly J.; Little, Edward E.; Brumbaugh, William G.; Mebane, Christopher A.

    2016-01-01

    Behavioral responses of aquatic organisms to environmental contaminants can be precursors of other effects such as survival, growth, or reproduction. However, these responses may be subtle, and measurement can be challenging. Using juvenile white sturgeon (Acipenser transmontanus) with copper exposures, this paper illustrates techniques used for quantifying behavioral responses using computer assisted video and digital image analysis. In previous studies severe impairments in swimming behavior were observed among early life stage white sturgeon during acute and chronic exposures to copper. Sturgeon behavior was rapidly impaired and to the extent that survival in the field would be jeopardized, as fish would be swept downstream, or readily captured by predators. The objectives of this investigation were to illustrate protocols to quantify swimming activity during a series of acute copper exposures to determine time to effect during early lifestage development, and to understand the significance of these responses relative to survival o