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Fishery Bulletin 107(2) 
Table 3 
Quillback rockfish ( Sebastes maliger) body composition data averaged for early-stage embryos and hatched preparturition larvae 
(mean ±1 SD). Comparisons of early versus late-stage samples revealed net changes that occurred during embryogenesis. “Early” 
included stages 2-3 embryos, and sample size ( n ) was 3 maternal females, except for ash (n= 2). “Late” included stage-10 larvae, 
n = 4, except ash (n= 3). Comparisons only included those samples for which all proximate composition data, except ash, were 
available. Each sample was a composite of hundreds of embryos or larvae from the same parent. Dry masses did not sum to 
exactly 100% because lipid was determined by a separate process from protein and ash. 
Early 
Late 
% Change 
Wet mass per individual ( pg) 
649 ±60 
884 ±72 
36.2 
Moisture (%) 
78.5 ±1.7 
87.3 ±0.8 
11.3 
Dry mass per individual (pg) 
140 ±13 
112 ±15 
-19.5 
Protein mass per individual (pg) 
90.3 ±9.9 
73.0 ±12.1 
-19.2 
Lipid mass per individual (pg) 
43.5 ±6.8 
28.9 ±4.7 
-33.6 
Ash mass per individual (pg) 
8.61 ±0.57 
9.71 ±0.90 
12.8 
Protein (% wet mass) 
13.9 ±1.08 
8.22 ±0.74 
-41.0 
Lipid (% wet mass) 
6.70 ±0.85 
3.25 ±0.35 
-51.4 
Lipid (% dry mass) 
31.0 ±1.9 
25.7 ±2.2 
-17.3 
Total energy content per individual ( J) 
3.40 ±0.44 
2.52 ±0.40 
-25.9 
Energy density ( J/mg wet mass) 
5.24 ±0.52 
2.84 ±0.24 
-45.9 
Energy density (J/mg dry mass) 
24.3 ±0.9 
22.4 ±0.8 
-7.9 
Oil globule volume (nL) 
27.8 ±1.2 
13.7 ± .8 
-50.6 
(i.e., each time the ANOSIM p is calculated for a given 
R, its values will vary slightly). 
A multidimensional scaling (MDS) plot was construct- 
ed using XLStat (Addinsoft, New York, NY) based on 
the Aitchison distance matrix, to illustrate the degree 
to which the early-stage embryonic and hatched, pre- 
parturition samples were separated based on their FA 
compositions. Any differences in the rates at which 
individual FAs were depleted during embryogenesis 
were expected to change the overall FA profiles over 
time; any net change in overall FA profile that occurred 
between early embryonic and later larval stage samples 
were revealed in the MDS plot. 
In order to describe which individual FAs were re- 
sponsible for the differences in overall FA profiles be- 
tween early and late stage samples, we calculated the 
percentages of mass lost ( IML ) for each individual FA: 
IML = me — x 100%, ( 2 ) 
m l 
where m e = the average mass of a FA in four samples of 
early-stage embryos; and 
m l = the average mass of a FA in four samples of 
hatched larvae. 
Comparison to the percentage of total lipid mass lost 
enabled us to describe which FAs had been depleted most 
rapidly, and which had been largely conserved. Because 
the importance of any FA in metabolism may be revealed 
in a combination of the rates of use and the absolute 
mass used (i.e., its contribution to the overall loss of 
lipid), we also described changes in mass of each FA 
between early and late stage samples and the percentage 
of total FA mass loss ( TML ) they accounted for: 
TML = x 100%, (3) 
TM e - TM, 
where TM e = the average total mass of all FAs in four 
samples of early-stage embryos; and 
TMf - the average total mass of all FAs in four 
samples of hatched larvae. 
It is important to note that total lipid masses of samples 
were independently determined by separate processes 
from the FA analysis, so total lipid did not simply reflect 
the summed FA masses. 
Results 
Body composition and energy use 
As they developed, quillback rockfish embryos took on 
water to gain size while they consumed their stored 
lipids and, to a lesser extent, protein as energy sources. 
A typical quillback rockfish embryo gained over one- 
third its weight in water and lost nearly 20% of its dry 
mass through the observed course of development, from 
early embryonic stages to preparturition, hatched larvae 
(Table 3). Dry mass loss was comprised of 54% protein 
and 46% lipid. 
