The Joint Annual Scientific Meetings of the Endocrine Society of Australia and the Society for Reproductive Biology 2018

The effect of dietary protein content on reproductive physiology in mice (#337)

Peter K Ajuogu 1 , Robert Hart 2 , James McFarlane 1
  1. Centre for Bioactive Discovery in Health and Ageing, University of New England, Armidale, NSW, Australia
  2. University of New England, Armidale, NSW, Australia

It is known that the amount of protein in the diet can affect reproductive performance in many species. However, the mechanism of action is not entirely clear. In this study we compared the effect of feeding mice a low (8%) or high (35%) protein mouse chow to mice fed standard (22%) mouse chow on the ovary, uterus, and pregnancy outcomes. Energy and fat content were identical in all three diets. Adult virgin female mice (20 per group) were fed one of the three diets for 6 weeks and then 10 mice per group were euthanized on the day of oestrus as determined by vaginal lavage. The ovaries and uterus were collected and weighed. The remaining mice were then joined with a male mouse (previously fed on standard mouse chow) for two weeks and examined twice daily for vaginal plugs to determine conception day and then allowed to complete the pregnancy.

The mean ovarian weights at oestrus from mice fed the normal (43.8±4.2mg) and high (47.3±4.9mg) protein diets were not significantly different but significantly (P<0.02) heavier than those on low (29.2±4.1mg) protein diet. The oestrus uterine weight from the low protein diet (89.4±23.1mg) was significantly lower than those from the normal (169.0±24.3mg) and high (137.2±10.6mg) protein diet mice. However, the pregnancy rates were lower in both the low protein (70%) and high protein (80%) than the normal diet (90%).

In conclusion low protein diets result in low ovarian weights at oestrus which may reflect reduced follicular development and subsequent corpus luteum number and consequently lower steroid production reflected in the lower uterine weight. Although high protein did not affect either the ovarian and uterine weights the pregnancy success rate was similar to that of low protein diets. We are currently examining the endocrine and histological differences between the groups.