Abstract
Breastfeeding is widely regarded as the optimal form of feeding infants, as it provides both nutritional and physiological benefits. For example, breastfed infants generate greater intraoral suction and have higher amplitude muscle activities compared to bottle-fed infants, with downstream implications for motor function, development, and health. One mechanism that might explain these physiological differences is the structure of the nipple an infant is feeding on. Breasts in most mammals are ducted soft-tissue structures that require suction to be generated for milk to be released, whereas bottle nipples are hollow and allow milk to be acquired by compression of the nipple. We used a validated animal model (pigs) to test how being raised on a novel ducted nipple impacted feeding physiology and performance compared to infants raised on a standard (cisternic) nipple. At the end of infancy, we fed both groups with both nipple types and used high-speed videofluoroscopy synchronized with intraoral pressure measurements to evaluate feeding function. Nipple type did not have a profound impact on sucking or swallowing rates. However, when feeding on a ducted nipple, infant pigs raised on a ducted nipple generated more suction, consumed milk at a faster rate, swallowed larger boluses of milk, and had decreased likelihood of penetration and aspiration than those raised on a cisternic nipple. These data replicate those found when comparing breast- and bottle-fed infants, suggesting that a ducted, biomimetic nipple may provide bottle-fed infants with the physiologic benefits of breastfeeding.