AUTHOR=Li Zimei , Dong Yanpeng , Chen Sirun , Jia Xinlin , Jiang Xuemei , Che Lianqiang , Lin Yan , Li Jian , Feng Bin , Fang Zhengfeng , Zhuo Yong , Wang Jianping , Xu Haitao , Wu De , Xu Shengyu 

TITLE=Organic Selenium Increased Gilts Antioxidant Capacity, Immune Function, and Changed Intestinal Microbiota

JOURNAL=Frontiers in Microbiology

VOLUME=Volume 12 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2021.723190

DOI=10.3389/fmicb.2021.723190

ISSN=1664-302X

ABSTRACT=<p>Selenium is an indispensable essential micronutrient for humans and animals, and it can affect biological functions by combining into selenoproteins. The purpose of this study was to investigate the effects of 2-hydroxy-4-methylselenobutanoic acid (HMSeBA) on the antioxidant performance, immune function, and intestinal microbiota composition of gilts. From weaning to the 19th day after the second estrus, 36 gilts (Duroc × Landrace × Yorkshire) were assigned to three treatments: control group, sodium selenite group (0.3 mg Se/kg Na<sub>2</sub>SeO<sub>3</sub>), and HMSeBA group (0.3 mg Se/kg HMSeBA). Dietary supplementation with HMSeBA improved the gilts tissue selenium content (except in the thymus) and selenoprotein P (SelP1) concentration when compared to the Na<sub>2</sub>SeO<sub>3</sub> or control group. Compared with the control group, the antioxidant enzyme activity in the tissues from gilts in the HMSeBA group was increased, and the concentration of malondialdehyde in the colon had a decreasing trend (<italic>p</italic> = 0.07). Gilts in the HMSeBA supplemented group had upregulated gene expression of <italic>GPX2</italic>, <italic>GPX4</italic>, and <italic>SelX</italic> in spleen tissue, <italic>TrxR1</italic> in thymus; <italic>GPX1</italic> and <italic>SelX</italic> in duodenum, <italic>GPX3</italic> and <italic>SEPHS2</italic> in jejunum, and <italic>GPX1</italic> in the ileum tissues (<italic>p</italic> &lt; 0.05). In addition, compared with the control group, the expression of <italic>interleukin-1β</italic> (<italic>IL-1β</italic>), <italic>interleukin-6</italic> (<italic>IL-6</italic>), <italic>interleukin-8</italic> (<italic>IL-8</italic>), and <italic>monocyte chemotactic protein-1</italic> (<italic>MCP-1</italic>) in the liver, spleen, thymus, duodenum, ileum, and jejunum of gilts in the HMSeBA group were downregulated (<italic>p</italic> &lt; 0.05), while the expression of <italic>interleukin-10</italic> (<italic>IL-10</italic>) and <italic>transforming growth factor-β</italic> (TGF<italic>-β</italic>) in the liver, thymus, jejunum, and ileum were upregulated (<italic>p</italic> &lt; 0.05). Compared with the control group and the Na<sub>2</sub>SeO<sub>3</sub> group, HMSeBA had increased concentration of serum cytokines interleukin-2 (IL-2) and immunoglobulin G (IgG; <italic>p</italic> &lt; 0.05), increased concentration of intestinal immunoglobulin A (sIgA; <italic>p</italic> &lt; 0.05), and decreased concentration of serum IL-6 (<italic>p</italic> &lt; 0.05). Dietary supplementation with HMSeBA also increased the abundance of intestinal bacteria (<italic>Ruminococcaceae</italic> and <italic>Phascolarctobacterium</italic>; <italic>p</italic> &lt; 0.05) and selectively inhibited the abundance of some bacteria (<italic>Parabacteroides</italic> and <italic>Prevotellaceae</italic>; <italic>p</italic> &lt; 0.05). In short, HMSeBA improves the antioxidant performance and immune function of gilts, and changed the structure of the intestinal microflora. And this study provided data support for the application of HMSeBA in gilt and even pig production.</p>