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Animal Sciences and Industry

Animal Sciences and Industry

Kansas State University
232 Weber Hall
Manhattan, KS 66506-8028


Email: asi@ksu.edu


The average wean-to-estrus interval (WEI) on commercial farms is approximately 5 days with most sows bred within 7 days of weaning (Knox et al., 2013). Due to the energy and amino acid demands during lactation, many sows and gilts will have lost weight (body condition) during lactation. Large losses in body condition can potentially lead to a prolonged WEI in parity 1 and 2 females (Vargas et al., 2009). Although limited research exists on feeding strategies during the WEI, recent research has found little to no impact of increasing feed intake of a gestation diet or feeding a lactation diet between weaning and rebreeding (Graham et al., 2015; Almeida et al., 2018; Tables 1 and 2). Therefore, when transitioning into the WEI, it is recommended that weaned sows be provided 6 to 8 lb/d of the gestation diet to restore body reserves, then transition to gestation feed allowances based on body condition (Figures 1 and 2).