Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2002-6-7
pubmed:abstractText
The southern snow skink, Niveoscincus microlepidotus, exhibits an unusual biennial reproductive cycle with an extended gestation period of approximately 1 year. Morphological data were gathered on a monthly basis, providing a detailed picture of the reproductive cycle. Vitellogenesis begins in spring, immediately after parturition. Maximum follicular diameter is reached before the winter hibernation period and ovulation occurs the following spring. Embryos are fully developed and reach maximum size by early autumn. Yolk reserves are depleted before winter. Birth of between one and four young occurs the following spring. Plasma progesterone concentrations are low (2.7 +/- 0.9 ng mL(-1)) in post-partum females, begin to rise in autumn in vitellogenic females and peak (38.5 +/- 7.9 ng mL(-1)) in pre-ovulatory females after hibernation. Concentrations are high (15.4 +/- 5.9 ng mL(-1)) in early pregnancy and decline to basal levels before winter and well before birth in spring. Plasma oestradiol concentrations peak during vitellogenesis (1.0 +/- 0.3 ng mL(-1)) and decline to basal levels during pregnancy (0.2 +/- 0.03 ng mL(-1)). A second oestradiol peak occurs before parturition (0.7 +/- 0.2 ng mL(-1)). Thus, functional completion of vitellogenesis and gestation is achieved by autumn in successive years. The mechanisms that defer ovulation and parturition by a further six months are unknown.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1031-3613
pubmed:author
pubmed:issnType
Print
pubmed:volume
14
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
43-53
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Delayed ovulation and parturition in a viviparous alpine lizard (Niveoscincus microlepidotus): morphological data and plasma steroid concentrations.
pubmed:affiliation
School of Zoology, University of Tasmania, Hobart, Australia. Jane.Girling@utas.edu.au
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't