Effects of pre-weaning dietary substitutions on plasma insulin and glucose profiles in primiparous sows

The objective of this study was to investigate the effects of substituting 1kg of a standard lactation diet with 1kg of a sugar-rich (15.75DEMJ/kg) or fat-rich (23.85DEMJ/kg) diet during late lactation on blood glucose and insulin changes in primiparous sows. During a 4-week lactation period, 21 primiparous sows were fed to appetite with a standard lactation diet (14.10DE MJ/kg). At 9days before weaning, sows were assigned to a control (C, n=7), fat (F, n=6) or sugar (S, n=8) treatment. During the treatment period (from 8days before weaning until weaning), 1kg of the lactation diet was substituted with 1kg of a sugar-rich or fat-rich diet for S and F sows. At 3days before weaning, serial blood samples were collected for a total of 228min around feeding to establish pre- and postprandial plasma glucose and insulin concentrations. Preprandial plasma glucose and insulin concentrations did not differ between treatments (p>0.05); however, mean plasma glucose and insulin concentrations were higher for S compared to F (p0.05). The results from our study suggest that a sugar-enriched diet during the last week of lactation elevates circulating glucose and insulin concentrations and may potentially improve post-weaning fertility in primiparous sows. © 2012 Blackwell Verlag GmbH.