Effect of elevated summer temperatures on gonadal steroid production, vitellogenesis and egg quality in female Atlantic salmon
Groups of Tasmanian female Atlantic salmon Salmo salar L. were maintained at 14, 18 and 22ࠃ from mid-summer (January). Blood plasma levels of 17߭oestradiol (E2), testosterone (T), cortisol and vitellogenin (Vtg) were measured at regular intervals, and in autumn (April) temperatures were reduced to 8...
| Published in: | Journal of Fish Biology |
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| Main Authors: | , , , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Blackwell
2003
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| Subjects: | |
| Online Access: | http://hdl.handle.net/10072/14623 https://doi.org/10.1046/j.1095-8649.2003.00137.x |
| Summary: | Groups of Tasmanian female Atlantic salmon Salmo salar L. were maintained at 14, 18 and 22ࠃ from mid-summer (January). Blood plasma levels of 17߭oestradiol (E2), testosterone (T), cortisol and vitellogenin (Vtg) were measured at regular intervals, and in autumn (April) temperatures were reduced to 8ࠃ to facilitate spawning and egg incubation. Maintenance at 22ࠃ during vitellogenesis was associated with a general reduction in plasma E2 levels and an early reduction in plasma Vtg levels relative to those observed in fish held at 14 and 18ࠃ. Significantly reduced oocyte diameters in ova from fish held at 22ࠃ (5素mm cf. 5締mm) confirmed reduced maternal investment, and an increase in the incidence of previously undescribed chorion damage suggested that zonagenesis may also have been impaired. As a result, the fertility and survival of ova from fish exposed to 22ࠃ (69 and 42%, respectively) were significantly reduced relative to those of ova from fish maintained at 14ࠃ (93 and 86%) and 18ࠃ (86 and 84%). Copyright 2003 The Fisheries Society of the British Isles Full Text |
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