Pregnancy-Associated Alterations of Peripheral Blood Immune Cell Numbers in Domestic Sows Are Modified by Social Rank

During pregnancy, the maternal immune system is characterized by changes in various immune functions. Nevertheless, pregnancy-associated immune changes and the interplay of rank-associated and gestation-induced immunomodulations are still poorly investigated in sows. Important aspects of blood cellular immunity, cortisol concentrations, and the influence of social rank position during pregnancy were investigated. The results showed that the numbers of various lymphocyte subpopulations decreased, while neutrophils and plasma cortisol concentrations increased during pregnancy. Those pregnancy-associated alterations in the immune system were affected especially in middle-ranking sows, indicating that social rank can influence the immune system and endocrine status in sows during pregnancy