Lefebvre et al.: Reproductive ecology and size-dependent fecundity in Eopsetta jordani 
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Table 2 
Macroscopic stage and histological phase descriptions of ovarian development in petrale sole (Eopsetta jordani). Oocyte stages used 
in this study are based on descriptions in Wallace and Selman (1981) and Lowerre-Barbierie et al. (2011), and terminology follows 
Brown-Peterson et al. (2011), with modifications specific to petrale sole. BV=blood vessel; CT=connective tissue; GVB=germinal vesicle 
breakdown; GVM=germinal vesicle migration; HO=hydrated oocyte; LC=leading oocyte cohort; MB=muscular bundle; PG=primary 
growth oocyte; and POF=postovulatory follicle complex; Vtgl, Vtg2, and Vtg3 represent the primary, secondary, and tertiary vitellogenic 
oocytes, respectively. 
Macroscopic 
stage 
Macroscopic description 
Histological 
phase 
Subphase 
Histological description 
1 (Immature) 
Ovaries are small and elongate, 
pale or flesh-colored with no 
black pigmentation, and tear 
easily. 
Immature 
Lamellae are tight and generally well 
organized with only PG present. No 
atresia or prominent BV, MB, or CT 
present. Ovarian wall is thin. 
2 (Developing) 
Oocytes are visible, giving 
ovary a uniformly granular 
appearance. Ovary is well 
vascularized and opaque. 
Developing 
Spawning 
capable 
Early 
developing 
Late 
developing 
LC is at Vtgl or Vtg 2. Minor atresia may 
be present. By the end of this stage, 
there is a distinct hiatus between 
primary and secondary growth oocytes. 
Note: there appears to be no distinct 
cortical alveolar stage oocytes in 
petrale sole. 
LC is at Vtg3, GVM, or GVB stage. 
Generally, when ovary is at this stage, 
the earliest secondary growth oocyte 
stage is Vtg2 or later. Minor atresia may 
be present, and there is no evidence of 
recent spawning (no POFs present) 
3 (Ripe or 
Large, translucent hydrated 
Actively 
LC may be Vtg3, GVM, GVB, or HO. At 
running ripe) 
eggs visible, scattered 
throughout ovary. Hydrated 
eggs may run under slight 
pressure. 
spawning 
least one stage of POF present and 
readily distinguishable from older 
atresia. Standing stock of secondary 
growth oocytes at the Vtg3. Moderate 
delta and gamma atresia may be present. 
4 (Spent) 
Ovaries are flacid; brown, or 
dark red in color and may 
have excess ovarian fluid. 
Residual oocytes (vitellogenic 
or hydrated) may or may not 
be visible. 
Regressing 
PG are the most advanced nonatretic 
oocyte present; if present, secondary 
growth oocytes are undergoing alpha or 
beta atresia. Lamellae appear loose and 
disorganized. Initially, POFs are readily 
distinguishable from other atretic 
material. BV, MB, and CT are prominent. 
5 (Resting) 
Ovaries are reduced in size, 
are firmer to the touch 
(compared to spent), are 
pink in color, have no 
discernable oocytes, and have 
a gelatinous texture. 
Regenerating 
PG dominate. Some beta atretic oocytes may 
be present but delta and gamma atresia 
dominate. Lamellae more organized 
compared with “regressing” ovary. BV, 
MB, and CT are prominent. Ovarian wall 
is thick. 
significantly between lobes (P= 0.88) or location within 
lobes (P- 0.97). Subsequently, 2 fecundity subsamples 
were collected from the middle portion of either the blind- 
or eyed-side ovarian lobe. 
In the 2015-2016 reproductive season, weighed subsa¬ 
mples for fecundity analyses were 0.5-1.0 g. Upon prelim¬ 
inary analysis of these samples, subsample weights were 
reduced to 0.25-0.50 g in the 2016-2017 season. All oocytes 
in weighed subsamples were counted by using a stereomi¬ 
croscope, and oocyte density was calculated as quotient of 
the oocyte count and subsample weight. Potential annual 
fecundity was estimated gravimetrically by multiplying 
the oocyte density by the ovarian weight. Relative PAF 
was calculated as the quotient of PAF and somatic weight 
(total weight minus ovarian weight). Estimates from the 
2 subsamples were averaged, and the coefficient of varia¬ 
tion was calculated. Samples were excluded from further 
analyses when the coefficient of variation exceeded 0.15 
(n= 5). Fecundity estimates are potential values because 
any potential down-regulation through atresia was not 
accounted for. 
Estimates of PAF and relative PAF were developed to 
evaluate the effects of maternal size on egg production. For 
most finfish, absolute fecundity increases geometrically 
