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Stephen D. Mccormick - One of the best experts on this subject based on the ideXlab platform.
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Upper thermal tolerance and heat shock protein response of juvenile American shad (Alosa sapidissima)
Estuaries and Coasts, 2019Co-Authors: Shannon M. Bayse, Amy M. Regish, Ciaran A. Shaughnessy, Stephen D. MccormickAbstract:Juvenile American shad (Alosa sapidissima) experience a wide range of temperatures in rivers before migrating to the ocean. Temperatures in these freshwater environments can vary greatly spatially, seasonally, year-to-year, and can be impacted by anthropogenic factors such as power plant discharge or climate change. Currently, there is uncertainty concerning juvenile American shad thermal tolerance due to a lack of a well-controlled study. Here, we report results of laboratory experiments to establish the upper thermal tolerance and heat shock protein response of juvenile American shad exposed to gradually increasing temperatures. Upper thermal tolerance was determined to be 35 °C (median; range = 34–36 °C) when fish were acclimated to 25 °C and temperatures were raised 1 °C day−1. Heat shock protein response was indicated by changes in branchial mRNA abundance of the inducible heat shock protein 90 alpha (hsp90α), which was significantly elevated (more than 5-fold increase) at 30 °C, and highest in fish that had reached their upper thermal maximum between 34 and 36 °C. Our findings indicate a higher upper thermal tolerance than previously reported for juvenile American shad, and an onset temperature of hsp90α induction at 30 °C, a temperature juvenile American shad commonly experience during summer months.
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proximate composition lipid utilization and validation of a non lethal method to determine lipid content in migrating american shad Alosa sapidissima
Journal of Fish Biology, 2018Co-Authors: Shannon M. Bayse, Amy M. Regish, Stephen D. MccormickAbstract:Lipid content forms the most important energy reserve in anadromous fish and can limit survival, migration and reproductive success. A fat meter was evaluated and compared with a traditional extractive method of measuring available lipid for migrating American shad Alosa sapidissima in the Connecticut River, U.S.A. The fat meter gives rapid (<10 s) and non-lethal lipid measurements, whereas traditional methods require lethal sampling that is both time consuming and expensive. The fat-meter readings had a strong relationship to traditional lipid extractions for 60 fish, 30 whole body (R2 = 0·72) and 30 fillet only (R2 = 0·81). Additional validation showed that fat-meter readings captured the gradual decrease of lipid in individual fish over time, were not affected by removal of gonads or scales and were stable for fish exposed to water or air for 24 h after death. These experiments indicate that the fat meter can be used as a reliable tool for future A. sapidissima energetic studies, allowing for larger sample sizes and non-lethal sampling.
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Proximate composition, lipid utilization and validation of a non-lethal method to determine lipid content in migrating American shad Alosa sapidissima.
Journal of fish biology, 2018Co-Authors: Shannon M. Bayse, Amy M. Regish, Stephen D. MccormickAbstract:Lipid content forms the most important energy reserve in anadromous fish and can limit survival, migration and reproductive success. A fat meter was evaluated and compared with a traditional extractive method of measuring available lipid for migrating American shad Alosa sapidissima in the Connecticut River, U.S.A. The fat meter gives rapid (
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182 The ontogeny of salinity tolerance in the American shad, Alosa sapidissima
2013Co-Authors: Joseph Zydlewski, Stephen D. MccormickAbstract:Abstract: Larval and juvenile American shad (Alosa sapidissima) raised from eggs in the laboratory were subjected to biweekly 24-h seawater (35 ppt) challenges. There was no survival in seawater before 36 days post-hatch, and most mortalities occurred within 2 h of transfer. Twenty-four hour survival reached 89 % in seawater at 45 days post-hatch (when larval–juvenile metamorphosis occurred), 96 % at 58 days post-hatch, and 92–100 % from 58 to 127 days post-hatch. Survival in seawater for 24 h was a good indicator of long-term survival and growth. Seawater tolerance was associated with gill development and increased gill Na +,K +-ATPase activity, which occurred at the onset of the larval–juvenile metamorphosis (3 months prior to the peak of migration). Gill Na +,K +-ATPase activity increased threefold in juvenile shad acclimated to 35-ppt seawater, reached peak levels 5 days after transfer, and remained elevated with respect to controls. Plasma sodium and chloride increased 12 and 11%, respectively, within 48 h of seawater exposure. Plasma sodium recovered to initial levels and plasma chloride stabilized at a level 10 % higher than initial levels after 5 days. Ionic perturbations that occurred at elevated salinities stabilized when gill Na +,K +-ATPase activity increased. Résumé: Des aloses savoureuses (Alosa sapidissima) larvaires et juvéniles élevées depuis l’oeuf dans le laboratoire ont été soumises à des stimulations par l’eau de mer (35 parties par millier) pendant 24 h deux fois par semaine. On n’a pas enregistré de survie dans l’eau de mer avant 36 jours après l’éclosion et la plus grande partie de la mortalité est survenue dans un déla
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Developmental and environmental regulation of chloride cells in young American shad, Alosa sapidissima.
The Journal of experimental zoology, 2001Co-Authors: Joseph D Zydlewski, Stephen D. MccormickAbstract:Location, abundance, and morphology of gill chloride cells were quantified during changes in osmoregulatory physiology accompanying early development in American shad, Alosa sapidissima. During the larval-juvenile transition of shad, gill chloride cells increased 3.5-fold in abundance coincident with gill formation, increased seawater tolerance, and increased Na + ,K + - ATPase activity. Chloride cells were found on both the primary filament and secondary lamellae in pre-migratory juveniles. Chloride cells on both the primary filament and secondary lamellae increased in abundance (1.5- to 2-fold) and size (2- to 2.5-fold) in juveniles held in fresh water from August 31 to December 1 (the period of downstream migration) under declining temperature. This proliferation of chloride cells was correlated with physiological changes associated with mi- gration (decreased hyperosmoregulatory ability and increased gill Na + ,K + -ATPase activity). In- creases in chloride cell size and number of fish in fresh water were delayed and of a lower magnitude when shad were maintained at constant temperature (24°C). When juveniles were acclimated to seawater, chloride cell abundance on the primary filament did not (though size increased 1.5- to 2- fold), but cells on the secondary lamellae disappeared. Na + ,K + -ATPase was immunolocalized to chloride cells in both fresh water and seawater acclimated fish. The disappearance of chloride cells on the secondary lamellae upon seawater acclimation is evidence that their role is confined to fresh water. The proliferation of chloride cells in fresh water during the migratory-associated loss of hyperosmoregulatory ability is likely to be a compensatory mechanism for increasing ion up- take. J. Exp. Zool. 290:73-87, 2001. © 2001 Wiley-Liss, Inc. The mechanisms of osmoregulation in teleosts acclimated to seawater (SW) have been aggres- sively studied and are relatively well understood. Chloride cells in the gill have been convincingly shown to be the site of ion excretion in fish accli- mated to hypersaline environments (Keys and Willmer, '32; Foskett and Scheffey, '82). Euryha- line fish can tolerate a wide range of salinities during their life history, and chloride cells have been demonstrated to enlarge and proliferate upon acclimation to increased salinity in a number of teleosts (Karnaky, '86). Chloride cells are rich in Na
Ted Rineer - One of the best experts on this subject based on the ideXlab platform.
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A Reliable Tag-Recapture Technique For Estimating Turbine Passage Survival: Application to Young-of-the-Year American Shad (Alosa sapidissima)
Canadian Journal of Fisheries and Aquatic Sciences, 1992Co-Authors: Paul G. Heisey, Dilip Mathur, Ted RineerAbstract:A new technique (HI-Z Turb'N Tag, U.S. Patent No. 4,970,988) for estimating turbine passage survival was applied to juvenile American shad (Alosa sapidissima) under three operating conditions at a hydroelectric project. Fish are fitted externally with the Turb'N tag and introduced into turbine penstocks. The Turb'N Tag inflates after turbine passage and buoys fish to the surface for recapture and examination; after removal of tags, fish are held to assess long-term effects. Almost all (96%) test (299) and control (300) fish were recovered; average recovery time was less than 9 min. The overall short-term (1 h) survival of test fish, adjusted for control, was 97%; 24- and 48-h survivals were 98 and 94%, respectively. The 48-h survival of test fish was 98–100% for mixed flow and Kaplan turbines and 66.8% for the mixed flow unit in the vented mode. Acute control mortality was negligible (
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a reliable tag recapture technique for estimating turbine passage survival application to young of the year american shad Alosa sapidissima
Canadian Journal of Fisheries and Aquatic Sciences, 1992Co-Authors: Paul G. Heisey, Dilip Mathur, Ted RineerAbstract:A new technique (HI-Z Turb'N Tag, U.S. Patent No. 4,970,988) for estimating turbine passage survival was applied to juvenile American shad (Alosa sapidissima) under three operating conditions at a hydroelectric project. Fish are fitted externally with the Turb'N tag and introduced into turbine penstocks. The Turb'N Tag inflates after turbine passage and buoys fish to the surface for recapture and examination; after removal of tags, fish are held to assess long-term effects. Almost all (96%) test (299) and control (300) fish were recovered; average recovery time was less than 9 min. The overall short-term (1 h) survival of test fish, adjusted for control, was 97%; 24- and 48-h survivals were 98 and 94%, respectively. The 48-h survival of test fish was 98–100% for mixed flow and Kaplan turbines and 66.8% for the mixed flow unit in the vented mode. Acute control mortality was negligible (< 5%). Our technique offers several significant advantages over traditional net recapture methods: applicable to wide rang...
Meredith L Bartron - One of the best experts on this subject based on the ideXlab platform.
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microsatellite dna markers for american shad Alosa sapidissima and cross species amplification within the family clupeidae
Molecular Ecology Notes, 2007Co-Authors: Shannon E Julian, Meredith L BartronAbstract:Sixteen microsatellite loci were identified and characterized for American shad (Alosa sapidissima). The number of alleles per locus observed ranged from eight to 32 and averaged 15.4 alleles. Average observed heterozygosity was 81.1%. The markers were screened using four other species from the family Clupeidae. Amplification success among Alosa species was 79.2% with 81.6% polymorphism among those markers that amplified successfully. Amplification success was poor in Dorosoma (31.3%). Due to allelic diversity and estimates of heterozygosity, these markers can be useful in A. sapidissima for population level analyses, parentage assignment and broodstock management.
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Microsatellite DNA markers for American shad (Alosa sapidissima) and cross‐species amplification within the family Clupeidae
Molecular Ecology Notes, 2007Co-Authors: Shannon E Julian, Meredith L BartronAbstract:Sixteen microsatellite loci were identified and characterized for American shad (Alosa sapidissima). The number of alleles per locus observed ranged from eight to 32 and averaged 15.4 alleles. Average observed heterozygosity was 81.1%. The markers were screened using four other species from the family Clupeidae. Amplification success among Alosa species was 79.2% with 81.6% polymorphism among those markers that amplified successfully. Amplification success was poor in Dorosoma (31.3%). Due to allelic diversity and estimates of heterozygosity, these markers can be useful in A. sapidissima for population level analyses, parentage assignment and broodstock management.
Paul G. Heisey - One of the best experts on this subject based on the ideXlab platform.
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A Reliable Tag-Recapture Technique For Estimating Turbine Passage Survival: Application to Young-of-the-Year American Shad (Alosa sapidissima)
Canadian Journal of Fisheries and Aquatic Sciences, 1992Co-Authors: Paul G. Heisey, Dilip Mathur, Ted RineerAbstract:A new technique (HI-Z Turb'N Tag, U.S. Patent No. 4,970,988) for estimating turbine passage survival was applied to juvenile American shad (Alosa sapidissima) under three operating conditions at a hydroelectric project. Fish are fitted externally with the Turb'N tag and introduced into turbine penstocks. The Turb'N Tag inflates after turbine passage and buoys fish to the surface for recapture and examination; after removal of tags, fish are held to assess long-term effects. Almost all (96%) test (299) and control (300) fish were recovered; average recovery time was less than 9 min. The overall short-term (1 h) survival of test fish, adjusted for control, was 97%; 24- and 48-h survivals were 98 and 94%, respectively. The 48-h survival of test fish was 98–100% for mixed flow and Kaplan turbines and 66.8% for the mixed flow unit in the vented mode. Acute control mortality was negligible (
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a reliable tag recapture technique for estimating turbine passage survival application to young of the year american shad Alosa sapidissima
Canadian Journal of Fisheries and Aquatic Sciences, 1992Co-Authors: Paul G. Heisey, Dilip Mathur, Ted RineerAbstract:A new technique (HI-Z Turb'N Tag, U.S. Patent No. 4,970,988) for estimating turbine passage survival was applied to juvenile American shad (Alosa sapidissima) under three operating conditions at a hydroelectric project. Fish are fitted externally with the Turb'N tag and introduced into turbine penstocks. The Turb'N Tag inflates after turbine passage and buoys fish to the surface for recapture and examination; after removal of tags, fish are held to assess long-term effects. Almost all (96%) test (299) and control (300) fish were recovered; average recovery time was less than 9 min. The overall short-term (1 h) survival of test fish, adjusted for control, was 97%; 24- and 48-h survivals were 98 and 94%, respectively. The 48-h survival of test fish was 98–100% for mixed flow and Kaplan turbines and 66.8% for the mixed flow unit in the vented mode. Acute control mortality was negligible (< 5%). Our technique offers several significant advantages over traditional net recapture methods: applicable to wide rang...
Joseph A. Mckenzie - One of the best experts on this subject based on the ideXlab platform.
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Usefulness of Meristic and Morphometric Characters in Discriminating Populations of American Shad (Alosa sapidissima) (Ostreichthyes:Clupeidae) Inhabiting a Marine Environment
Canadian Journal of Fisheries and Aquatic Sciences, 1992Co-Authors: Gary D. Melvin, Michael J. Dadswell, Joseph A. MckenzieAbstract:American shad (Alosa sapidissima) concentrate each summer in the basins of the inner Bay of Fundy during their coastal migration. Tag returns from 6124 marked shad indicated that these fish return to every important shad spawning stream on the Atlantic coast. Ten meristic and 16 morphometric characters of shad collected from 14 rivers (range: Florida to Quebec) were used to develop linear discriminant functions (LDF). Variables which differed significantly (p
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usefulness of meristic and morphometric characters in discriminating populations of american shad Alosa sapidissima ostreichthyes clupeidae inhabiting a marine environment
Canadian Journal of Fisheries and Aquatic Sciences, 1992Co-Authors: Gary D. Melvin, Michael J. Dadswell, Joseph A. MckenzieAbstract:American shad (Alosa sapidissima) concentrate each summer in the basins of the inner Bay of Fundy during their coastal migration. Tag returns from 6124 marked shad indicated that these fish return to every important shad spawning stream on the Atlantic coast. Ten meristic and 16 morphometric characters of shad collected from 14 rivers (range: Florida to Quebec) were used to develop linear discriminant functions (LDF). Variables which differed significantly (p < 0.05) between the sexes, year of sampling, and the time of collection during the spawning run were removed prior to LDF classification. The highest mean percent correct classification was achieved by the allocation of fish into regional groups, after classification into individual rivers, using pooled meristic and morphometric variables: 87.2% for males and 82.4% for females. The functions were then used to assign shad from a mixed populations (Cumberland Basin) to individual rivers and regions. Of these, 10.9% were assigned to rivers south of Cape...