Penaz and Gajdusek, 1979



Citation


Penaz, M. and Gajdusek, J. (1979) Early development of bream, Abramis brama, from the water reservoir Mostiste, Czechoslovakia. Folia Zool., pp. 347-360

Associated characteristics


Species Development state Trait Primary Data Secondary Data
Abramis brama Spawning conditions Spawning substrate Under natural conditions of bream spawning, when the bottom is covered with mud and oxygen content is decreased, this adapatation enables an ecologically favourable incubation because the eggs stick to aquatic plants and others substrates Phytophils
Abramis brama Egg Egg adhesiveness External layers became highly sticky Adhesive
Abramis brama Egg Incubation time 64-78 hours at 20°C 71.0 days
Abramis brama Egg Degree-days for incubation The motility of embryos inside the shells increased and the first embryos hatched 64 hours from the beginning of development at a water temperature of 20°C, i.e. 1280 hours degree, within the following 14 hours most of the embryos hatched 64.0 °C * day
Abramis brama Egg Temperature for incubation Reared at a constant temperature of 20°C 20.0 °C
Abramis brama Egg Egg size after water-hardening The formation of perivitelline space ended approximatively at the end of this step when the average egg diameter increased 1.64 times, i.e., to 1.80 mm 1.64 mm
Abramis brama Egg Oocyte diameter Ripe, freshly stripped eggs were yellow-gray in colour and their average size before the activation and swelling was 1.10 mm 1.1 mm
Abramis brama Larvae Temperature during larval development Reared at 19.5-20.5 20.0 °C
Abramis brama Larvae Reaction to light "At a size of 5.1 to 6.2 mm, the embryos remained passive and typical ""hanging up"" by means of sticky glands of walls and submerged objects reached its maximum in this step. From time to time, the embryos wriggled up to the surface and thereafter slowly sank in a passive way. They were indifferent to light and did not seek shade or cover" Photopositive
Abramis brama Larvae Full yolk-sac resorption A complete resorption of the yolk-sac characterizing the beginning of this step took place at the average length of larve L= 7.7 to 7.9 mm on the 7th to the 8 th of development, i.e. 4-5 after hatching 4.5 °C * day
Abramis brama Larvae Onset of exogeneous feeding During the 6th of development, i.e. the 3rd after hatching, most individuals began to ingest exogeneous food. Their average total length was 6.6 mm 6.0 °C * day
Abramis brama Larvae Initial larval size Their average total length at hatching was 4.55 4.55 mm
Abramis brama Larvae Larvae behaviour The hatched embryos mostly rested in a passive way on the bottom and only some of them hung themselves by their sticky glands onto walls or onto submerged silon threads, under natural conditions, the embryos stuck themselves onto submerged plants Demersal