ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Induced Ovulation of Southern Flounder Paralichthys lethostigma Using Gonadotropin Releasing Hormone Analogue Implants (1996)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of the World Aquaculture Society 27 (1996), S. 0 
    Details
    ISSN: 1749-7345
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Implanted pellets that provide a sustained release of [D-Ala6 Des-Gly10] LHRH-ethylamide (GnRHa) were used to induce maturation and ovulation of Southern flounder Paralichthys lethostigma. Of the 12 females whose ovaries contained follicles with a maximum diameter ≥500 μm, 11 ovulated for the first time within 90 h of hormone implantation. Only 1 fish with a maximum follicle diameter less than 500 μm ovulated within 2 wk after implantation. Ovulated eggs were manually stripped from the females and mixed with sperm from several males. Most females were spawned 1 to 3 times on consecutive days with variable fertility. One female was spawned 11 times producing 668,000 eggs. Fertility was evaluated by examining the incubated eggs for early stages of embryonic cleavage. The percentage of fertile eggs in subsamples of incubated eggs ranged from 7–95%. The results indicate that GnRHa implants can be used to induce repeated ovulation in this species. The variability in fertility is discussed in relation to egg quality.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1749-7345.1996.tb00263.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    The Annual Reproductive Cycle of the White Bass Morone chrysops (1995)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of the World Aquaculture Society 26 (1995), S. 0 
    Details
    ISSN: 1749-7345
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: The gametogenic cycle of the white bass Moronc chrysops was characterized for one year at monthly intervals by measuring circulating levels of the sex steroid hormones testosterone (T) and 11-ketotestosterone (11-KT) in males, and 17β-estradiol (E2) and T in females. Vitellogenin (VTG), the egg yolk precursor, was also measured in female blood plasma. Gonadal status of individual fish was assessed by histological evaluation, measurement of oocyte diameters, and spermintion response. At the onset of vitellogenesis (October), blood plasma levels of E2 and T were low, but increased significantly as the spawning period (March-April) approached and oocytes attnined their maximum diameter. All stages of oocyte development were observed in mature females, indicating that the white bass is a multiple-clutch, groupsynchronous spawner. Androgen levels increased in males throughout the reproductive cycle and reached maximal levels during the spawning period. The increase in androgens coincided with sperm production and spermintion in males. The circannual endocrine and gonadal development patterns observed in white bass were similar to those of other members of genus Moronc.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1749-7345.1995.tb00253.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Effective GnRHa dose and gamete ratio for reproduction of southern flounder, Paralichthys lethostigma (Jordan and Gilbert 1884) (2004)
    Oxford, UK : Blackwell Science Ltd
    Aquaculture research 35 (2004), S. 0 
    Details
    ISSN: 1365-2109
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2109.2004.01168.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Production of Southern Flounder Paralichthys lethostigma Juveniles in an Outdoor Nursery Pond (1997)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of the World Aquaculture Society 28 (1997), S. 0 
    Details
    ISSN: 1749-7345
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1749-7345.1997.tb00859.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Hormone Induced Spawning of Summer Flounder Paralichthys dentatus (1997)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of the World Aquaculture Society 28 (1997), S. 0 
    Details
    ISSN: 1749-7345
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: During their first year in captivity, summer flounder Paralicthys denratus were induced to spawn with gonadotropin releasing hormone analogue (GnRHa) implants, injected carp pituitary extract (CPE) or human chorionic gonadotropin (hCG) injections. The percentage of fertile eggs was greatest (69%) in CPE-treated females. CPE, but not GnRHa or hCG, was capable of stimulating oocyte growth (increased follicle diameter during vitellogenesis) followed by ovulation. Fish with maximum ovarian follicle diameters between 180 and 435 μm at the initiation of CPE injections produced the greatest percentage of fertile eggs. For most females, fertilization rate was greatest for the first batch of eggs ovulated. The mean fertilization rate for the first spawn of CPE-treated fish was 42% compared with 14% for the second spawn from the same fish. Fish with maximum initial follicle diameters of 585 40 μm that were implanted with GnRHa ovulated the greatest number of eggs, but fertility was low and variable. Approximately 35% of females injected with hCG ovulated a limited number of eggs, but only one hCG-treated female produced fertile eggs. Only a limited number of spermiating males were available for spawning trials. Hormone treatments used on females were ineffective for inducing or maintaining spermiation in male summer flounder.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1749-7345.1997.tb00964.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Absorption, body distribution, and excretion of dietary zinc by rainbow trout (Salmo gairdneri) (1987)
    Springer
    Fish physiology and biochemistry 3 (1987), S. 133-143 
    Details
    ISSN: 1573-5168
    Keywords: dietary zinc absorption ; zinc excretion ; zinc retention
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Rainbow trout (Salmo gairdneri) were held in metabolizable energy chambers at Standard Environmental Temperature (15°C) for 72h following a single feeding of a semi-purified test diet containing tracer quantities of a radioisotope of zinc (65Zn) and different combinations of dietary calcium level and zinc source. Gill wastes, urine, and feces were separately collected. After 72h, the fish were killed, and samples of the following tissues removed: eyes, skin, muscle, blood, bone, liver, bile, kidney, gill, spleen, stomach, pyloric caeca, intestine, gonad, and remaining carcass. Radioactivity in the tissues and wastes was determined and the body distribution of the ingested zinc was quantified. Approximately 58% of the administered dose of65Zn was recovered. Of the recovered dose, 43.2% was present in the gastro-intestinal tract, 27% in the feces, 14% in the gill water, 16% in the body of the fish, and less than 1% in the urine. Of individual tissues, the gill, liver, kidney, and spleen had concentrations of65Zn higher than blood, while the remaining tissues had lower concentrations. Body and tissue levels were increased but not significantly by feeding65Zn as an amino acid chelate, compared to feeding as inorganic65Zn, while dietary calcium level had no effect. The results of this study indicate that the gills play a major role in excretion of dietary zinc, while the urine plays a minor role.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02180415
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Effects of triiodothyronine and propylthiouracil on thyroid function and smoltification of coho salmon (Oncorhynchus kisutch) (1987)
    Springer
    Fish physiology and biochemistry 4 (1987), S. 121-135 
    Details
    ISSN: 1573-5168
    Keywords: salmon ; smoltification ; thyroid ; receptor ; thyroxine ; triiodothyronine ; propylthiouracil ; growth ; osmoregulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Yearling coho salmon (Oncorhynchus kisutch) were fed diets containing triiodothyronine (T3; 4 or 12gmg), propylthiouracil (PTU; 1.5 or 6.0 mg/g), or both T3 (12μg/g) and PTU (1.5 mg/g) from January 10 to May 29. Plasma T4 and T3, concentrations were maintained within normal physiological limits in all groups of treated fish. Increases in plasma thyroxine (T4) occurred in late April in groups receiving the high dose of T3 or PTU, or the combination of T3, and PTU. Peaks of plasma T4 occurred in May in the other groups. Thyroid follicle epithelial cell height was increased in the groups in the following order: highest; PTU (6.0 mg/g), PTU (1.5 mg/g), PTU + T3, control, T3 (4gmg/g), T3 (12μg/g); lowest. In March specific binding of T3 by liver nuclei was not affected by treatment with T3 (12μg/g) but was decreased 30% by treatment with PTU (6.0μg/g). Body growth, food conversion efficiency, and pigmentary changes were increased by T3 (12μg/g), decreased dose-dependently by PTU, and unaffected by the other dietary treatments. All treatments altered body proximate composition. Food consumption and the ability to osmoregulate in seawater were decreased in fish fed 6.0 mg/g PTU, but were unaffected by the other dietary treatments. These results suggest that during smoltification: 1) Thyroid hormones may be involved in control of thyroidal function and body growth and pigmentary changes, 2) Hypo-osmoregulatory competence is not further stimulated by exogenous T3 and 3) PTU does not block T4 synthesis but may block T3, action by interfering with nuclear T3 binding.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02110879
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Relationship between metabolic and reproductive hormones in salmonid fish (1989)
    Springer
    Fish physiology and biochemistry 7 (1989), S. 147-155 
    Details
    ISSN: 1573-5168
    Keywords: reproductive cycle ; metabolism ; estrogen ; vitellogenin ; insulin ; thyroid hormones ; salmon ; ovulation ; gonadotropin ; eggs
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Circulating concentrations of estradiol (E2), vitellogenin (VTG), thyroxine (T4), triiodothyronine (T3) and insulin were measured in reproductively maturing four and five year-old Atlantic salmon. Blood samples were collected from the fish in seawater for one year prior to their spawning in November in fresh water. In females, E2 and VTG were low but detectable from December to July, and then increased to peak levels in September and October. Plasma levels of T4 and T3 were relatively constant in winter and spring, and decreased in July. Plasma concentration of T4 increased in November when the fish returned to fresh water. Plasma T3 levels remained low during the autumn. Both T4 and T3 levels tended to be higher in males than in females during September through November. Plasma insulin concentrations increased during the spring to peak values in May, and then decreased in June and July in fish of both sexes. There was a significant elevation of plasma insulin in males during October, and the levels in males tended to be higher than those found in females during final maturation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00004701
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Thyroid hormones in brown trout (Salmo trutta) reproduction and early development (1994)
    Springer
    Fish physiology and biochemistry 13 (1994), S. 485-493 
    Details
    ISSN: 1573-5168
    Keywords: brown trout ; reproduction ; induced spawning ; thyroid hormones ; GnRHa ; triiodothyronine ; egg quality ; larval development ; aquaculture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Gravid brown trout (Salmo trutta) females were injected with various doses of a synthetic gonadotropin-releasing hormone analog (GnRHa), given with or without an injection of triiodothyronine (T3), in order to investigate the potential of T3 (a) to enhance the stimulatory effect of GnRHa on ovulation, and (b) to enhance the growth and survival of the produced progeny. From the time the hormonal treatments were initiated until ovulation was detected 5–38 days later, endogenous plasma T3 levels increased from an average of 3.6 to 11.6 ng ml−1. Injection with 20 mg T3 kg−1 body weight, further elevated plasma T3 levels at ovulation (16.0 ng ml−1. Mean time to ovulation was reduced significantly in fish injected with 10 μg kg−1 of GnRHa, whereas treatment with lower doses was ineffective. Injection with T3 did not enhance the ovulatory response of brown trout to GnRHa. Unfertilized eggs obtained from T3-injected females had a higher T3 content, suggesting a transfer of T3 from the maternal circulation into the oocytes. Maternal T3 injection had no effect on egg fertilization rates, embryo survival to eyeing and hatching, or the prevalence of abnormal larvae at the time of hatching. Length and weight gain of the progeny during yolk absorption was also not influenced by maternal T3 treatment. At the completion of yolk-sac absorption, progeny from females injected with T3 had a higher prevalence of skeletal abnormalities than controls. The results suggest that in teleosts like brown trout, which have high endogenous circulating T3 levels, treatment of females with T3 does not enhance responsiveness to GnRHa and it has the potential for deleterious effects on their offspring.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00004331
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Involvement of gonadal steroids in final oocyte maturation of white perch (Morone americana) and white bass (M. chrysops): in vivo and in vitro studies (1995)
    Springer
    Fish physiology and biochemistry 14 (1995), S. 489-500 
    Details
    ISSN: 1573-5168
    Keywords: gonad ; maturation ; Morone ; oocyte ; ovary ; perciform ; steroidogenesis ; steroids ; teleost
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Plasma estradiol-17β (E2), testosterone (T), 17α,20β-dihydroxy-4-pregnen-3-one (DHP) and 17α,20β,21-tri-hydroxy-4-pregnen-3-one (20β-S) levels were measured by radioimmunoassay (RIA) in white perch (Morone americana) and white bass (M. chrysops) that were induced to undergo final oocyte maturation (FOM) with human chorionic gonadotropin (hCG). Plasma DHP levels increased in females of both species in association with oocyte germinal vesicle migration (GVM) and germinal vesicle breakdown (GVBD) and decreased thereafter. Plasma 20β-S levels also increased with oocyte GVM in white bass, but were several-fold lower than DHP levels. Circulating E2 and T levels were greatest during GVM and GVBD in both species and decreased to low levels during oocyte hydration and ovulation. Follicles from white perch and white bass which received a priming injection of hCG in vivo, produced both DHP and 20β-S in vitro after exposure to hCG and their oocytes underwent GVBD. Ovarian incubates from unprimed fish of either species produced only E2 and T and their oocytes did not complete GVBD. Oocytes from unprimed bass, but not perch, matured when follicles were exposed to hCG in vitro. Both trilostane and cycloheximide blocked in vitro production of DHP and 20β-S and oocyte GVBD by white perch follices. DHP and 20β-S were equipotent inducers of FOM in the GVBD bioassay. None of several other structurally-related steroids tested were effective within a physiological range of concentrations. These results indicate a role for DHP and 20β-S in the control of FOM in white perch and white bass.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00004349
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...