Digestive differences in immunoglobulin G and lactoferrin among human, bovine, and caprine milk following in vitro digestion

Immunoglobulin G (IgG) and lactoferrin (Lf) play an important role in the protection and maturation of the neonatal immune system; however, the survival of IgG and Lf during gastrointestinal digestion and their digestive differences among human, bovine, and caprine milk remain unclear. This study investigated the digestive behaviour of IgG and Lf by simulating infant digestion of the milk of three species. Both IgG and Lf in human milk showed higher resistance to digestion than those in the other two types of milk. In addition, caprine milk IgG survived for a longer period after gastrointestinal digestion than bovine milk IgG. These static in vitro digestion results showed that IgG and Lf from human and caprine milk are digested more slowly from those from bovine milk.