Harlow Smith, 

Title:

Impact of Nipple Design on Feeding Biomechanics in Term and Preterm Piglets

Abstract:

Disruptions to development are known to impair critical physiological functions in vertebrates. In infant mammals, premature birth is known to compromise feeding performance, especially in establishing breastfeeding. Instead, these infants must often be fed with bottles, which use hollow nipples, unlike the ducted structure of breast tissue. Here we investigate the performance of term and preterm infants while feeding on a standard, hollow bottle nipple and on a biomimetic, ducted bottle nipple, as a proxy for breastfeeding. We raised one full-term litter and one preterm litter of pigs, and raised half of each litter on each nipple type. At 7 days of age, we evaluated feeding kinematics on both nipple types using high-speed biplanar videofluoroscopy. When feeding on a cisternic nipple, preterm infants compressed the nipple more to express milk and generated less suction than term infants. In contrast, term infants had greater posterior tongue movements than preterm infants which is likely a reflection of larger swallow volumes. These data suggest that gestational age at birth impacts tongue function during feeding. Most strikingly, the reliance on expression to acquire milk in premature infants points to a developmental disparity in oromotor functioning. Future research should examine mechanisms driving these differences in order to develop interventions to improve the suction-generating capacities of premature infants.