Document Detail


Sex ratio and litter size in the guinea-pig.
MedLine Citation:
PMID:  8958829     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
A significant relationship between sex ratio and litter size at birth was observed in the young of guinea-pigs caged singly from 8 weeks of age and during their first pregnancy; a male was present only at or around oestrus. Small litters (1-2 young) had significantly more males than did large litters (4-5 young). Such a relationship was not apparent in animals housed communally, whether young or older or in their second pregnancy. Litters in late pregnancy (day 63) or at delivery were significantly smaller than at mid-pregnancy (day 35). A significant negative relationship was found between litter size and bodymass at birth and to at least 63 days of age. Growth rates during the period of lactation were lower in animals born in large litters. The possible adaptive significance of a plastic relationship between litter size and sex ratio is considered together with the physiological mechanism that might be involved.
Authors:
M Peaker; E Taylor
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Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of reproduction and fertility     Volume:  108     ISSN:  0022-4251     ISO Abbreviation:  J. Reprod. Fertil.     Publication Date:  1996 Sep 
Date Detail:
Created Date:  1997-01-02     Completed Date:  1997-01-02     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0376367     Medline TA:  J Reprod Fertil     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  63-7     Citation Subset:  IM    
Affiliation:
Hannah Research Institute, Ayr, UK.
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MeSH Terms
Descriptor/Qualifier:
Animals
Birth Weight
Female
Gestational Age
Guinea Pigs / physiology*
Litter Size*
Male
Pregnancy
Sex Ratio*
Social Environment*

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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