Fig. 1 in Induced spawning and early ontogeny in hatchery-reared catfish Zungaro jahu (Siluriformes: Pimelodidae)

Fig. 1. Steromicroscopic images of fresh oocytes (a; 1.6 mm in diameter), eggs (b-k; ~2.4 mm in diameter), embryos (l-m; ~2.4 mm in diameter), and free embryo (l-n; 4.3 mm TL) of jahu in hatchery conditions. a) recently spawned oocyte covered by the jelly coat (arrow); b) egg showing a large perivitelline space and two blastomeres of same size (45 min post fertilization, PF); c) dorsal view of egg seen in b; d) egg with four blastomeres of same size (50 min PF); e) egg with eight blastomeres of same size (50 min PF); f) egg with sixteen blastomeres of same size (1 h 15 min PF); g) egg with thirty-two blastomeres of same size (1 h 20 min PF); h) morula stage (2 h 10 min PF); i) half of the yolk sphere (circa 50% epiboly) was covered with the blastoderm (4 h 50 min PF); j) formation of the yolk plug circa 90% epiboly (6 h 30 min PF); k) end of epiboly with closure of embryo ring (blastopore) (7 h 30 min PF); l) embryo exhibiting optic calyx (OC), otic vesicle (OV), Kupffer's vesicle (KV), and 13 somites (10 h 30 min); m) embryo within egg envelop exhibiting free, beating tail (13 h 30 min PF); n) free embryo, the almost transparent body is involved by the primordial fin fold; head and anterior part of body over the yolk sac; non-pigmented retina; mouth is closed; notochord slightly flexed; 39.1 ± 2.0 miotomes (circa 6 h post hatching).