Experiments on the respiration and in situ development of Baltic herring (Clupea harengus L.) eggs
Braum, E. (1985). Experiments on the respiration and in situ development of Baltic herring (Clupea harengus L.) eggs. Int. Rev. gesamten Hydrobiol. 70(1): 87-100
In: Internationale Revue der gesamten Hydrobiologie. Wiley-VCH: Berlin. ISSN 0020-9309, more
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Keywords |
Biological development > Embryonic development In situ tests Incubation Malformations Oxygen consumption Population functions > Mortality Respiration > Aerobic respiration Substrata > Artificial substrata Clupea harengus Linnaeus, 1758 [WoRMS] Marine/Coastal |
Abstract |
A primary blastodise develops 2 hours and 40 minutes after artifical fertilization at 8 °C and 15 %o S. The egg then begins embryonic development. When incubated in water with the oxygen concentration reduced to 50 % or 15 % saturation, the oxygen consumption of the eggs decreased to 73 % or 41 % of normal, respectively. For the in situ experiments, eggs and sperm taken from living fishes were spread on plexiglas plates in a way that monolayers adhered to the surface. The plates were then moored to buoys at two depths in a spawning area at Pötenitzer Wiek near Travemünde. Egg mortality increased with the duration of incubation. About 90 % of the spring spawn died before hatching, but only a 10 % mortality occurred among those spawned in autumn. Scanning electron microscope examination revealed structural changes on the egg surfaces caused by bacteria and particles of sediment. The role for survival of the pattern formed by the eggs as they adhere to the surface is discussed. |
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