Temporal Dynamics of the Gut Bacteriome and Mycobiome in the Weanling Pig

Abstract

Weaning is a period of environmental changes and stress that results in significant alterations to the piglet gut microbiome and is associated with a predisposition to disease, making potential interventions of interest to the swine industry. In other animals, interactions between the bacteriome and mycobiome can result in altered nutrient absorption and susceptibility to disease, but these interactions remain poorly understood in pigs. Recently, we assessed the colonization dynamics of fungi and bacteria in the gastrointestinal tract of piglets at a single time point post-weaning (day 35) and inferred interactions were found between fungal and bacterial members of the porcine gut ecosystem. In this study, we performed a longitudinal assessment of the fecal bacteriome and mycobiome of piglets from birth through the weaning transition. Piglet feces in this study showed a dramatic shift over time in the bacterial and fungal communities, as well as an increase in network connectivity between the two kingdoms. The piglet fecal bacteriome showed a relatively stable and predictable pattern of development from Bacteroidaceae to Prevotellaceae, as seen in other studies, while the mycobiome demonstrated a loss in diversity over time with a post-weaning population dominated by Saccharomycetaceae. The mycobiome demonstrated a more transient community that is likely driven by factors such as diet or environmental exposure rather than an organized pattern of colonization and succession evidenced by fecal sample taxonomic clustering with nursey feed samples post-weaning. Due to the potential tractability of the community, the mycobiome may be a viable candidate for potential microbial interventions that will alter piglet health and growth during the weaning transition.

Impact of Yeast-Derived β-Glucans on the Porcine Gut Microbiota and Immune System in Early Life

“…This is in line with previous studies [ 46 , 47 ]. In another study, alpha diversity reached a plateau from day 24 onwards [ 21 ]. This outcome likely has to do with the earlier time of weaning (day 21), demonstrating the dominant role that the weaning transition has on gut microbiota maturation.…”

“…As outlined above, several studies have investigated the development of the gut microbiota, and the effects of dietary fibres on porcine gut health and the immune function in the post-weaning phase. However, only a few studies have focused their research on the immediate and early period [ 21 ]. To the best of our knowledge, no in vivo studies have investigated the effects of yeast-derived β(1,3/1,6)-glucans (MacroGard ® ) on both the porcine gut microbiota and immune system in early life, despite the promising results from several in vitro studies [ 22 , 23 ].…”

Characterization of Kazachstania slooffiae, a Proposed Commensal in the Porcine Gut

“…However, details on its growth or interactions with the bacteriome are lacking. Previous inferred interactions have suggested that K. slooffiae has positive interactions with beneficial bacteria such as Prevotella [ 19 , 20 ]. K. slooffiae was previously assessed for its ability to utilize organic acids and amino acids as carbon and energy sources [ 22 ], and this fungus was not able to utilize lactic, butyric, proprionic, or acetic acid as a sole carbon source in vitro ; however, this ability in the gut environment cannot be ruled out [ 22 ].…”

“…K. slooffiae has been found to be the predominant post-weaning fungi in the gastrointestinal (GI) tract and feces of piglets. This fungus persists in adult pigs across geography and may play a role in providing nutritional benefits to pigs [ 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 ]. K. slooffiae is a yeast that is closely related to species such as Candida (Kazachstania) pintolopesii and Candida ( Kazachstania ) bovina , and it is a member of the Kazachstania ( Arxiozyma ) telluris species complex [ 27 ].…”

“…Kurtzman et al utilized strains originally isolated from horse and porcine ceca and described K. slooffiae as vegetative with spherical to ellipsoidal cells and multilateral budding, resulting in lobate colony growth and lacking true hyphae. In swine, positive inferred interactions have been found between K. slooffiae and beneficial gut bacteria including Prevotella and Lactobacillus [ 19 , 20 ]. Despite these previous studies, little is known about this fungus and its role in modulating the microbial milieu in the gut, and thus, piglet health, growth, and disease resistance.…”