264 A holistic nutritional approach for modulation of microbiome to improve pig performance and support health

Abstract

The gut microbiome is in an intimate symbiosis with its host and their interactions have profound effects on the physiology, health, and performance of pigs across all life stages. Within this symbiosis, the establishment of a healthy and productive gut microbiome is influenced by numerous factors including diet and non-diet related factors, though feed composition and feeding strategy remain major driving forces. Stepping back to a higher vantage point, a holistic, practical approach to promotion of a gut microbiome through nutrition so that it functions in a manner that is beneficial to the host and decreases the host’s susceptibility to disease can be discussed. Practical nutritional considerations include introduction of ingredients and nutrients that support normal gastrointestinal tract (GIT) development, understanding how different bioactive compounds interact with the microbiome, and how macronutrients, such as protein, can influence microbiome composition and function. For GIT development, establishment of early, sustained feed intake is crucial for mucosal barrier function and to reduce disruptions to normal GIT transit or disruptions in normal intake patterns, which can help minimize niche proliferation of opportunistic and pathogenic species. Introduction of fibrous feedstuffs in the immediate pre- and postweaning periods can aid in promotion of feed exploration and transitionary feed intake. Selection of fiber sources and the respective type of fiber they provide can differentially aid in the establishment and adaptation of the microbiome to utilize solid feed postweaning. In addition to fiber, other nutritional bioactive technologies (such as phytogenics, organic acids, and pre-/pro-/post-biotics can exert suppressive effects on certain pathogenic bacterial pathogens and improve the relative robustness and resilience of microbial populations though their mechanisms of action differ. Due to these different mechanisms and interactions with the microbiome, the time it takes for the gastrointestinal environment to respond to either promotive or suppressive approaches can vary, from a few days to a few weeks, and needs to be considered when developing a postweaning feeding strategy. The combination of promotive and suppressive effects by these bioactives can aid in creation of a microbiome that is more resistant to disturbances from stressor exposures. When reflecting on ingredients that provide other key macronutrients, protein source selection can prove difficult when trying to control the proteolytic activity of microbes and subsequent proliferation of pathogens while the GIT is developing. Incorporation of further processed protein sources, like soybean meal, into diet formulation can improve protein digestibility and reduce the total undigested protein that reaches the hindgut, improving the synchrony and utilization of fiber and protein fractions in the hindgut. These nutritional considerations, when taken together, provide a roadmap to more successful postweaning feeding transitions and improved microbiome functionality and productivity that have positive impacts on animal gastrointestinal health.