Optimal allocation of reproductive effort: manipulation of offspring number and size in the bank vole

Citation
Ta. Oksanen et al., Optimal allocation of reproductive effort: manipulation of offspring number and size in the bank vole, P ROY SOC B, 268(1467), 2001, pp. 661-666
Citations number
28
Categorie Soggetti
Experimental Biology
Journal title
PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON SERIES B-BIOLOGICAL SCIENCES
ISSN journal
09628452 → ACNP
Volume
268
Issue
1467
Year of publication
2001
Pages
661 - 666
Database
ISI
SICI code
0962-8452(20010322)268:1467<661:OAOREM>2.0.ZU;2-W
Abstract
The number of offspring attaining reproductive age is an important measure of an individual's fitness. However, reproductive success is generally cons trained by a trade-off between offspring number and quality. We conducted a factorial experiment in order to study the effects of an artificial enlarg ement of offspring number and size on the reproductive success of female ba nk voles (Clethrionomys glareolus). We also studied the effects of the mani pulations on growth, survival and reproductive success of the offspring. Po tentially confounding effects of varying maternal quality were avoided by c ross-fostering. Our results showed that the number of offspring alive in th e next breeding season was higher in offspring number manipulation groups, despite their smaller body size at weaning. Offspring size manipulation had no effect on offspring growth or survival. Further, the first litter size of female offspring did not differ between treatments. In conclusion, femal es may be able to increase the number of offspring reaching reproductive ag e by producing larger litters, whereas increasing offspring size benefits n either the mother nor the offspring.