Fully
vitellogenic oocyte amino acid profile of Siberian sturgeon (Acipenser
baerii, Brandt)
E. Gisbert, P. Williot, F. Castelló-Orvay-2002
Journal of
Applied Ichthyology, 18(4-6): 347-350
Abstract:
The amino acid (AA) composition of
different fully vitellogenic oocyte batches was determined. These oocytes
were obtained from seven mature cultured Siberian sturgeon (Acipenser
baerii) females with high reproductive potential and quality of their
sexual products (fertilization rate 70-98%). Essential amino acids (EAA)
represented 46-50% of the total AA content. Nonessential amino acids
represented 47-54% of the total AA oocyte content. In all studied oocyte
batches, leucine, lysine, arginine and isoleucine were the most abundant
EAA, representing 27% of the total AA content. The AA composition of
Siberian sturgeon oocytes found in the current study is similar to those
determined in cultured white sturgeon (A. transmontanus) with the
exception of threonine, proline, histidine and aspartic acid, which are 25
and 35% higher and 20 and 30% lower than in white sturgeon secondary
oocytes, respectively. Differences in the AA profile between these two
closely related species were detected and could be related to female age,
stage of oocyte development, different broodstock management and feeding
strategies, species-specific AA metabolism and/or trophic ecology. The
results could be a valuable tool for determining nutritional requirements
for first feeding larvae and a first step toward better knowledge of the
nutrition and physiology of early life stages of Siberian sturgeon.
(Laboratorio de Acuicultura, Departamento de Biología Animal, Facultat
de Biología, Universitat de Barcelona, Av. Diagonal, 645, E-08028
Barcelona, Spain. E-mail: gisbert@porthos.bio.ub.es)