Possibilities
of androgenesis in sturgeons: sterlet as a model animal
Aquaflow Technical Leaflet 2001-29
European Network for the Dissemination of Aquaculture
RTD Information (Q5CA-2000-30105) and previously FAIR-3837, URL: http://www.aquaflow.org/
Many species of the sturgeon family (Acipenseridae)
are cultured throughout the world. The main interest in farming is caviar
production, while in Europe, sturgeons, including the sterlet (Acipenser
ruthenus) are valuable export products. As a consequence of the changes
on the territory of the former Soviet Union, the reduction of spawning
grounds in the wild and the dramatic decline in fisheries catches, some
species, such as the Atlantic sturgeon (Acipenser
sturio) are only found in increasingly small numbers.
One of the possibilities to preserve valuable genetic
resources is the application of modern genetic-biotechnological methods.
Among these, androgenesis – the development of an embryo containing only
paternal chromosomes due to failure of the egg to participate in
fertilization - is one of the possible methods and the focus of this
research.
Sterlet (Acipenser
ruthenus) was used as the experimental model. Albinism in males was used
as a phenotypic marker. Naturally-coloured sterlet females fished from the
Danube were also used. Gamma irradiation at 30 kR was used for the
inactivation of the female genome. A heat shock was applied in order to
restore the diploid status of eggs 85 minutes post fertilisation in a 38°C
water bath for a period of 150 seconds. The subsequent fertilisation and
hatching results were registered - 11.2 % fertilisation and 5.1 % hatching
were achieved with successful androgenesis. Following optimisation of
experimental parameters, entirely albino sterlet progeny was obtained.
These results confirm the suitability of the
methodology for the preservation of genetic information in diminishing
populations. When used in combination with sperm cryopreservation
techniques, the given species could potentially be restored decades after
the collection of milt.
For more information:
Dr. Miklós Bercsényi
Veszprém University
Deak Ferenc street 16.
8361 Keszthely, Hungary
Tel:: +36 20 971 16 055
E-mail: bm@georgikon.hu