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Figure 2 
Histological cross sections of Atka mackerel ovaries stained with hematoxylin and eosin stain, except E and F: (A) 
cross section of ovary with early perinucleus oocyte (egg stage 1) (x 200); (B) cross section of ovary with late 
perinucleus oocyte (egg stage 2) (x 79); (C) cross section of ovary with late perinucleus oocyte (egg stage 2) and 
cortical alveoli stage (egg stage 3) (x 79); (D) cross section of ovary with oil droplet oocyte (egg stage 4), both 
cortical alveoli and oil droplets appear as clear droplets (x 200); (E) cross section of ovary with oil droplet oocyte 
(egg stage 4), oil droplets are staining deep black, cortical alveoli are clear (Sudan black) (x 200); (F) cross section 
of ovary with oil droplet oocyte (egg stage 4), cortical alveoli are staining PAS positive, oil droplets appear clear 
(PAS) (x 200); (G) cross section of ovary with vitellogenic oocyte (egg stage 5), yolk is staining eosin-positive (x 79); 
(H) cross section of ovary with early migratory nucleus stage (egg stage 6), yolk droplets fuse to yolk platelets (x 
79); (I) cross section of ovary with late migratory nucleus oocyte, nuclear wall is disintegrated (x 200); (J) cross 
section of ovary with early hydrated oocyte (egg stage 7) (x 79); (K) cross section of ovary with late hydrated oocyte 
(egg stage 8) (x 79); (L) cross section of ovary with atretic hydrated oocyte (x 79); (M) cross section through ovary 
showing alpha atresia in a yolked oocyte (x 79); (N) cross section through ovary with post-ovulatory follicle (x 79). 
Roman numberals I-VIII=oocyte stages 1-8. AO=atretic oocyte; CA=cortical alveoli; HAO=hydrated atretic oo- 
cyte; MN=migratory nucleus; OD=oil droplets; POF=postovulatory follicle; and YG=yolk globules. 
