Additional file 3 - datasets and scripts for performance analysis

All calculations and statistical analyses were performed using R (version 4.0.2). The data on ADG, feed intake, and body composition were analysed in R with linear mixed-effect models using the “lmer” function of the lme4 package. The category (IUGR, NORM) and sex (female, castrate) were considered fixed effects, and the litter of origin was considered a random effect. The two-way interaction between the two fixed effects was consistently assessed and removed if not significant. The pig was considered the experimental unit. Analysis of data regarding ADG was conducted individually for the lactation, starter, grower, and finisher periods. Data on feed intake were analysed separately for the grower and finisher periods. Analysis of body composition data was conducted separately at weaning, the beginning of the grower period, and the end of the finisher period.