Early Career Award Speaker: Optimizing nutrition to support immune and brain development in livestock and humans.

Strong evidence links establishment of a stable microbiota with development of tissues and organ systems, immunity, and cognitive abilities, and this communication network is often referred to as the gut-brain axis. Nutrition serves as a powerful tool capable of exerting influence over each of these domains, and optimal early-life nutrition is particularly important to avoid permanent alterations in structure and function within the body. Activation of the immune system elicits a coordinated set of metabolic, physiological, and behavioral events, all of which result in reduced animal growth. Thus, immune stimulation serves to alter whole-body protein metabolism to repartition amino acids away from lean tissue accretion and toward production of specialized immune cells and mediators. Additionally, normal gastrointestinal function may be compromised during sickness, as evidenced by decreases in nutrient digestion and absorption. From a nutritional perspective, these circumstances are quite challenging to manage because disease-challenged animals not only consume less feed, but also experience metabolic shifts that compromise profitability. Complex interrelationships between the periphery and brain permit nutritional status, immune activation, and microbial-derived products to alter neurodevelopment and cognitive function. Based on similarities in patterns of gut and brain development, the pig has emerged as a translational animal model for studying effects of early-life nutrition on cognitive function. Use of sensitive analytical techniques, including neuroimaging, behavioral assessments, and molecular quantification, permits an in-depth understanding of how nutrition affects neurodevelopmental patterns. Recent advances to quantify longitudinal volumetric changes during the pre-pubertal period, along with the integration of a high-quality brain atlas and magnetic resonance imaging sequences optimized for the domestic pig, have permitted researchers to establish quantifiable neurodevelopmental links between pigs and humans. As such, nutritional strategies designed to support immune and brain development, potentially through alteration of the microbiota, are currently being tested to benefit health and well-being of animals and humans alike.