species: rhesus macaque

Take It Easy: Neonatal Milk Hormones Influence Infant Social and Cognitive Behavior

Take It Easy: Neonatal Milk Hormones Influence Infant Social and Cognitive Behavior

Email, texts, IM, Facebook, Instagram—in the age of social media, there is no shortage of ways to send a message from one person to another. But is mother’s milk the original social network? Many of milk’s ingredients are believed to act as signaling factors that convey a “message” from mother to infant. Over the last decade, researchers have worked on decoding these messages, with a particular focus on the hormone cortisol. Milk cortisol levels are associated with infant growth and infant temperament in rhesus macaques, and hypothesized to send the message to be more cautious and prioritize growth over behavioral activity. A newly published study expands on this hypothesis and tests whether milk cortisol levels during the first weeks of life predict behavior and cognitive performance months later. The results suggest that far from being an instant messenger, milk’s signal may have effects well after it is received. Read More...

Milk Protein Comparison Unveils Nutritional Gems for Human Infants

Milk Protein Comparison Unveils Nutritional Gems for Human Infants

As any new parent can tell you, human newborns are very needy—and for good reason. Born at an earlier developmental stage than their primate relatives, human infants must accomplish a great deal of fetal development (some say the equivalent of nine more months!) outside of the womb. Responsibility for this “fourth trimester” falls squarely on the shoulders of human breast milk, and so it is no surprise that decades of research have searched for attributes in human milk that support the unique developmental needs of human infants. While much of the focus has gone to milk fats and carbohydrates, a new study has turned the attention to milk proteins (1). Utilizing new methods in protein identification, Beck et al. present the most comprehensive human milk proteome (the list of the types and quantities of all proteins in milk) to date, as well as the first milk proteome for a nonhuman primate, the rhesus macaque. Despite having less total protein than rhesus macaque milk, Beck et al. found that human milk has more than three times the types of proteins in rhesus milk and higher quantities of nearly every milk protein that the two species share. Their findings demonstrate that from digestion, to immunity, to neurodevelopment, human infants get more of a boost from milk proteins than their primate cousins. Read More...