ISSN 1062-3604, Russian Journal of Developmental Biology, 2009, Vol. 39, No. 3, pp. 165–170. © Pleiades Publishing, Inc., 2009.
Original Russian Text © S.A. Murzina, Z.A. Nefedova, T.R. Ruokolainen, O.B. Vasil’eva, N.N. Nemova, 2009, published in Ontogenez, 2009, Vol. 39, No. 3, pp. 208–214.
Reproduction, spawning, and egg development are
the key events in the life cycle of Atlantic salmon
L. The content of lipids in the egg is one of bio-
chemical markers of egg maturity and competence for
fertilization, which is considered an index of offspring
viability (Kryzhanovskii, 1960; Haliloglu et al., 2003).
Lipids are important sources of metabolite energy and
structural substances as well as bioeffectors of intracel-
lular biochemical reactions, cell–cell interactions, and
various physiological processes (Kreps, 1981; Dyatlo-
vitskaya and Bezuglov, 1998). The lipid spectrum in
developing eggs is a marker of the larval energy
requirements during the transition to exogenous feed-
ing (Haliloglu et al., 2003). The level of lipids largely con-
centrated in the egg yolk determines the life strategy of the
future embryo and larva and allows us to evaluate the
capacity of their adaptation to changing environmental
conditions as well as egg quality (Shatunovskii, 1980a,
1980b; Sidorov, 1983; Tocher, 2003; Peng et al., 2003).
Despite numerous studies of the patterns in the pro-
portion of individual lipids during certain developmen-
tal stages in different ﬁsh species including salmonids
as well as in sea urchins and amphibians (Ando, 1962;
Bolgova et al., 1985; Nefedova, 1989; Halver, 2000;
Novikov, 2000; Tocher, 2003; Cejas et al., 2004), the
functional role of lipids and variation in lipid spectra
during Atlantic salmon embryogenesis remain under-
The goal of this work was to study the lipid content
(11 groups of lipids) in mature eggs of Atlantic salmon
before spawning and during embryonic devel-
opment in eggs (6 stages) as well as to elucidate the
functional role of lipid storage and utilization.
MATERIALS AND METHODS
Artiﬁcially fertilized eggs of Atlantic salmon from a
ﬁshery station was delivered to the laboratory and incu-
. Eggs developed on grids in daily
replaced riverine water. The developing salmon eggs
were sampled at the following developmental stages
(Ryzhkov and Krupen’, 2004): (1) before fertilization;
(2) blastodisc formation (3 h); (3) blastodisc cleavage
(day 7); (4) tail bud formation (day 27); (5) onset of
heart tube pulsation and circulation (day 40); (6) onset
of eye pigmentation (day 60); (7) transition to hatching
and partial hatching (day 108).
Samples (a single egg) were taken in 10–25 repli-
cates at each developmental stage and ﬁxed with 96%
ethanol (1 ml). The samples were homogenized in
10 volumes of chloroform/methanol (2 : 1) and stored
until analysis. Lipids were extracted in chloro-
form/methanol (2 : 1, v/v) by the method of Folch et al.
(1957) and fractionated on Silufol plates (Kavaler,
Czech Republic) in petroleum ether/diethyl ether/acetic
acid (90 : 10 : 1, v/v). Total phospholipids (PL), triglyc-
erides (TG), and cholesterol esters (CE) were quanti-
ﬁed by the hydroxamate method (Walch et al., 1965;
Sidorov et al., 1972); cholesterol (Ch), by the method
of Engelbrecht et al. (1974); and expressed as percent-
age of dry weight. Total phospholipids were separated by
high performance liquid chromatography (Arduini et al.,
1996) on a stainless steel column Nucleosil 100-7 (Elsiko,
BIOCHEMISTRY OF DEVELOPMENT
Dynamics of Lipid Content during Early Development
of Freshwater Salmon
S. A. Murzina, Z. A. Nefedova, T. R. Ruokolainen, O. B. Vasil’eva, and N. N. Nemova
Institute of Biology, Karelian Scientiﬁc Center, Russian Academy of Science,
ul. Pushkinskaya 11, Petrozavodsk, 185610 Russia
Received April 8, 2008; in ﬁnal form, August 14, 2008.
—Dynamics of lipid and phospholipid content was studied during early development of freshwater
L. from blastodisc formation (3 h) to hatching (108 days) as well as in eggs before fertili-
zation. High and stable content of total lipids including structural phospholipids as well as relatively high con-
tent of triglycerides and its slight increase at the time of hatching have been demonstrated, which can indicate
their utilization as the main energy source after hatching under conditions of deﬁcient food and low fry activity
for some time. Accumulation of a certain level of lipids in eggs before spawning is required for embryonic
development and high survival after hatching. The signiﬁcance of increasing and decreasing levels of structural
lipids modulating membrane enzyme activities in metabolic changes before hatching is discussed.
freshwater salmon, embryogenesis, lipids, phospholipids, triglycerides.