Raw potato starch diet supplement in weaned pigs could reduce Salmonella Typhimurium infection by altering microbiome composition and improving immune status

Seung-Won Yi; Han Gyu Lee; Eunju Kim; Young-Hun Jung; Eun-Yeong Bok; Ara Cho; Yoon Jung Do; Tai-Young Hur; Sang-Ik Oh

doi:10.3389/fvets.2023.1183400

Raw potato starch diet supplement in weaned pigs could reduce Salmonella Typhimurium infection by altering microbiome composition and improving immune status

Front Vet Sci. 2023 May 23:10:1183400. doi: 10.3389/fvets.2023.1183400. eCollection 2023.

Authors

Seung-Won Yi¹, Han Gyu Lee¹, Eunju Kim¹, Young-Hun Jung¹, Eun-Yeong Bok¹, Ara Cho¹, Yoon Jung Do¹, Tai-Young Hur¹, Sang-Ik Oh^{1

2}

Affiliations

¹ Division of Animal Diseases and Health, National Institute of Animal Science, Rural Development Administration, Wanju-gun, Jeollabuk-do, Republic of Korea.
² Laboratory of Veterinary Pathology, College of Veterinary Medicine, Jeonbuk National University, Iksan, Jeollabuk-do, Republic of Korea.

Abstract

Backgorund: Salmonella enterica serovar Typhimurium (ST) is one of the causative agents of gastroenteritis in pigs. Pigs fed a diet supplemented with raw potato starch (RPS) have improved gut health by the alteration of the microbiota composition and production of short-chain fatty acids (SCFAs). This study aimed to evaluate the effects of RPS supplementation in reducing infection severity and fecal shedding in ST-infected pigs.

Methods: The weaned experimental pigs were divided into two groups: CON (n = 6) fed a corn/soybean-based diet and TRT (n = 6) supplemented with 5% RPS. After 21 d, the pigs were inoculated with ST, and their body weight, clinical signs, and fecal shedding of ST were monitored for 14 d. At 14 d post-inoculation (dpi), the jejunum, cecum, ileum, and colon tissues were collected from euthanized pigs, and histopathological lesions and cytokine gene expression were compared. Additionally, blood samples at 2 dpi were analyzed for gene ontology enrichment. Moreover, the gutmicrobiome was analyzed using 16S rRNA metagenomic sequencing, and the SCFA concentration was measured using gas chromatography.

Results: The average daily weight gain was significantly higher in TRT than in CON during the ST infection period; however, histopathological lesion scores were significantly lower in TRT than in CON. The relative abundance of nine genera of butyrate- and acetate-producing bacteria significantly increased in TRT compared with that of only two acetate-producing bacteria in CON. Among the genes involved in the immune response, IL-18 expression level was significantly lower in the jejunum and colon in TRT than in CON. Furthermore, Reg3γ expression was significantly different in the cecum and colon of both groups.

Conclusion: The diet supplemented with RPS in weaned pigs could result in predominance of butyrate- and acetate-producing bacteria, reducing the severity of ST infection by improving the immune status.

Keywords: Salmonella Typhimurium; cytokine; diarrhea; microbiome; raw potato starch; resistant starch; transcriptome; weaned pig.

Grants and funding

This study was supported by the 2021 RDA Fellowship Program of the National Institute of Animal Science, Rural Development Administration, the “Cooperative Research Program for Agriculture Science and Technology Development (Project Title: Development of gut microbiota for preventing intestinal diseases and its impact on host immunity in pigs, Project No. PJ01564401),” and Rural Development Administration, Republic of Korea.