Investment by female mice in their first lactation impacts investment in the next lactation.
What is it about?
During lactation female mice increase their energy intake by about a factor of five over when they are not breeding. However after the initial increase in early lactation the intake reaches a plateau suggesting intake is limited. We have been interested in what imposes this limit. One idea is that the intake at peak lactation isn't limited but females choose how much to invest based on a trade off with their subsequent lactation performance. In this paper we manipulated how much females invested in litter number 1 and looked at how much they then invested in litter number 2. We found that there was indeed a trade ff between litters. In principle then the limit might not be a rigid physiological limit but part of a female investment strategy responsive to ecological context.
Why is it important?
Limits on maximal intake are important to understand because these limits impose constraints on performance in all sorts of different spheres - particularly reproduction.
The following have contributed to this page: Professor John Speakman