Additionally, preterm pigs have low circulating IGF-1 levels and immature immune, gut, and metabolic systems, making them sensitive to sepsis, hypoglycemia, and gut disorders such as NEC (Andersen et al., 2016; Nguyen et al., 2016; Holme Nielsen et al., 2018; Holgersen et al., 2020), for which they are a clinically relevant model of preterm infants. This evidence concerns the gene IGF1 and necrotizing enterocolitis.