The timing of mother-infant separation and its effect on postpartum estrus and subsequent conception in captive baboons (1999)

Valentine, B., Cary, M., Stanley, J. et al.

Abstract

Forced infant weaning at an early age is often practiced by primate breeding facilities to initiate the onset of postpartum estrus and, consequently, maximize reproduction. ... There was [indeed] a significant correlation between age at removal and duration until postpartum estrus, however, there was no correlation between infant removal age and duration until next conception. ... Postpartum cyclicity usually resumed before infant removal. Subsequent conception, however, was not significantly influenced by infant removal. This study indicates that early forced weaning did not accomplish the goal of increased reproductive output. These findings - in addition to the concern for proper psychological development - suggest the better strategy is to allow infants to be naturally weaned by mothers.