Gestational heat stress alters skeletal muscle gene expression profiles and vascularity in fetal pigs in a sexually dimorphic manner

Abstract

Background: There is evidence that sow heat stress (HS) during gestation affects fetal development with implications for impaired muscle growth. We have previously demonstrated that maternal HS during early to mid-gestation compromised muscle fibre hyperplasia in developing fetal pigs. Thus, we hypothesised these phenotypic changes are associated with a change in expression of genes regulating fetal skeletal muscle development and metabolism. To test this, at d 60 of gestation, RNA sequencing and immunohistochemistry were performed on fetal longissimus dorsi (LD) muscle biopsies collected from pregnant gilts that had experienced either thermoneutral control (CON, 20 °C, n = 7 gilts, 18 LD sa..