The Influence of Genotype and Seasonality on the Sow Colostrum Quality and Immunoglobulin G Content

The aim of this study was to investigate the influence of genotype (GT) and seasonality (NP) on the quality parameters of sow colostrum and evaluate the efficiency of the radial immunodiffusion (RID) analysis and the Brix refractometer in determining the IgG concentration. This study was conducted on 240 sows that originated from two genotypes, namely GT1 (TOPIGS, n = 120) and GT2 (Pig Improvement Company, n = 120), during the three farrowing periods: the winter farrowing period (WNP, n = 80), the summer farrowing period (SMP, n = 80) and the spring farrowing period (SSP, n = 80). The significant interaction effect was observed for protein (<i>p</i> < 0.0001), lactose (<i>p</i> < 0.05) and non-fat solids (SNT) (<i>p</i> < 0.001). At the same time, the interaction effect influenced the IgG concentration measured with the Brix refractometer (<i>p</i> < 0.0001) and RID (<i>p</i> < 0.0001). Pearson's correlation coefficient showed that Brix percentage was positively correlated with RID results (r = 0.52, <i>p</i> < 0.0001), while the Bland-Altman plots indicated a mean bias of -1.93. Partial eta-squared analysis (η²) showed that the genotype explained the largest proportion of variance in fat content (η² = 0.136) and IgG concentration (η² = 0.164), while interaction effects were largest for protein (η² = 0.072). The results of this study show that genotype and seasonality influence sow colostrum quality, which indicates the importance of genotype-seasonality interactions in breeding programs for optimizing the colostrum quality and piglet survival.