ABSTRACT: This study was conducted to evaluate how the amount and type of diet consumed during the wean-to-estrus interval (WEI) affects reproductive performance and WEI duration in sows. A total of 542 sows were distributed into the following treatment groups based on a 2 × 2 factorial design: feed amount during WEI (2.75 or 3.75 kg/day) and diet (gestation [G] or lactation [L]) groups. Dietary treatments were as follows: high supply of G diet (GH), low supply of G diet (GL), high supply of L diet (LH), and low supply of L diet (LL). Sows were randomly allocated to groups according to their body score Caliper and birth order. There was an interaction (P < 0.05) between the factors for WEI duration, which was 0.2 days shorter in the GH and LL groups than in the other groups. No difference was observed between treatments (P>0.05) for the birth rate, total births, stillbirths, or total litter weight. There was a trend (P