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 (vīt′l-ō-jĕn′ĭ-sĭs, vĭt′-)
Formation of the yolk of an egg.

vi′tel·lo·ge·net′ic (-jə-nĕt′ĭk), vi′tel·lo·gen′ic (-jĕn′ĭk) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(ˌvɪtələʊˈdʒɛnɪk) or


(Zoology) zoology producing or stimulating the formation of yolk
[C20: from vitellus + -genic]
ˌvitelloˈgenesis n
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References in periodicals archive ?
Oogonia were detected in the central germinal zone in multiplication, previtellogenic and vitellogenic (primary and secondary) stages and the mature stage of oogenesis.
3B), along with formation of oogonia, previtellogenic oocytes, and vitellogenic oocytes in females, but without any mature ovules (Fig.
The first visible sing of atresia in vitellogenic oocytes (stage 5 atretic oocytes), was the thickening of the zona radiata.
Vitellogenic mechanisms are central to species success in any given habitat, because they reflect species reproductive response to nutrients (Eckelbarger, 1994).
The most advanced germ cells in this phase were primary and secondary vitellogenic oocytes, which increased in diameter because of increased yolk in the cytoplasm.
While two of three August females exhibited early atresia (Table 2) and may not have ovulated, there was no sign of atresia in the vitellogenic follicles of the third female.
For morphological analyses, i.e., diameter of vitellogenic oocytes, the pellucid zone thickness and the follicular cell height, we selected 50 undamaged oocytes without retraction and with cuts crossing the nucleus for each of the studied species.
Stage III: late development or oogenesis, this phase is characterized by a narrowing of the connective tissue in favour of vitellogenic oocytes.
The presence of elevated GSIs and mature, vitellogenic oocytes was used to estimate reproductive season in weeks for each population of fishes.
The oocyte types I and II (not vitellogenic) were observed in all stages of the reproductive cycle.