HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Eisen, E. J. Articles by Roberts, R. C. Search for Related Content PubMed PubMed Citation Articles by Eisen, E. J. Articles by Roberts, R. C.

Postnatal Maternal Effects on Growth and Fat Deposition in Mice Selected for Large and Small Size¹

Institute of Animal Genetics, West Mains Road, Edinburgh, Scotland EH9 3JN

Abstract

A crossfostering experiment involving lines of mice selected for large (L) and small (S) 6-week body weight was designed to determine correlated responses in direct genetic and postnatal maternal genetic effects and postnatal litter size effects on fat deposition at 6 weeks of age. The gonadal fat pad was used as an index of adiposity. The L line exceeded the S line in both direct genetic and postnatal maternal genetic effects on weight and percentage (of body weight) of the gonadal fat pad. Postnatal maternal genetic effects were about one-third as large as direct genetic effects. A prenatal line x postnatal line interaction for weight and percentage of gonadal fat was caused by the inability of S line dams to provide sufficient milk to maintain normal development of L line young. Further evidence supporting this hypothesis was the high mortality rate among L line young reared by S line dams when compared with the mortality in all other subgroups. Increasing postnatal litter size reduced weight and percentage of gonadal fat, but this factor was of less importance than direct genetic effects. In general, the relative importance of direct genetic, postnatal maternal genetic and postnatal litter size effects was similar for metric measures of growth (body weight, body length and tail length) and for adiposity (gonadal fat pad weight and percentage). Rate of gonadal fat pad development relative to body weight was higher in line L than in line S. At a constant body weight, however, line L mice had less fat than line S mice.

¹ Paper No. 6452 of the Journal Ser. of the North Carolina Agr. Res. Service, Raleigh. Supported, in part, by NIH Research Grant AM21950.

² Permanent address: Dept. of Anim. Sci., North Carolina State Univ., Raleigh 27650.

³ Supported, in part, by an Underwood Fund Fellowship, Agricultural Research Council, and an Edinburgh University Biological Fellowship in the Dept. of Genetics.

⁴ Agricultural Research Council, Unit of Animal Genetics.