Nutritional and social cues influence the onset of puberty in California voles.

Weanling male California voles were housed individually in cages containing either bedding taken from their own mothers, from unrelated mothers, or clean woodshavings. Half of the males in each housing condition received fresh lettuce daily in addition to their standard diets. At 45 days of age males housed in clean bedding had heavier seminal vesicles than males housed in bedding from their own or an unrelated mother. However, males which received lettuce supplementation displayed large-sized seminal vesicles regardless of their housing condition. In a second study 45-47 day old females were housed either with an adult male, alone in the bedding of an adult male, or in clean bedding for 4 days. Again, one half of the females in each housing condition received lettuce daily in addition to their standard diet. Ovarian and uterine weights were heaviest in females that had direct contact with an adult male. Lettuce supplementation increased uterine weights in females housed alone in either clean or male-soiled bedding. Lettuce did not accelerate uterine growth in females co-habiting with males, presumably male contact causes maximal development. These data show that the ingestion of green vegetation may facilitate reproductive development in male and female voles, despite inhibitory social conditions.