Proteomics Analysis of Colostrum Samples from Sows Housed under Different Conditions

SIMPLE SUMMARY: Milk quality in sows is affected by various factors, including the living environment. However, changes in protein-expression profiles in the milk of sows housed under different conditions are still unclear. Accordingly, in this study, we performed proteomics analysis of colostrum from sows housed under different conditions. Our results showed that housing conditions affected protein expression, and the effects of housing conditions were observed in both pregnancy and lactation. In comparison, the differentially expressed proteins were related to the immune system and metabolic processes, particularly fat metabolism. These results revealed the physiological changes in sows under different housing conditions. Overall, these findings provided important insights into the care and management of sows to enhance milk quality. ABSTRACT: This study investigated the proteomic characteristics of colostrum for sows housed under different conditions. Among 12 gilts, four were housed in a gestation-crate and farrowing-crate combined housing system (CC) as controls, four were housed in a gestation-pen and farrowing-pen combined housing system (PP), and four were housed in a gestation-pen and farrowing-crate combined housing system (PC). Differentially expressed proteins in the colostrum (PP versus CC, and PC versus CC) were screened by proteomics technology, and bioinformatics analysis was then performed. Results showed that 93 proteins were differentially expressed in PP versus CC, and that 126 proteins were differentially expressed in PC versus CC. The differentially expressed proteins in the PP versus CC comparison were mainly enriched in interleukin (IL)-17, transforming growth factor-β, and nuclear factor-κ B signaling pathways, and in metabolic pathways, including glutathione metabolism, peroxisome, and carbon metabolism. In contrast, differentially expressed proteins in the PC versus CC comparison were enriched in the IL-17 signaling pathway, cholesterol metabolism, and peroxisome proliferator-activated receptor signaling pathway. In conclusion, the housing environment appeared to affect the colostrum composition of sows by acting on their immune system and metabolic processes, particularly fat metabolism.