Monobutyrin Can Regulate the Gut Microbiota, Which Is Beneficial for the Development of Intestinal Barrier Function and Intestinal Health in Weaned Mice.

In this study, we investigated the effect of monobutyrin (MB) on the gut microbiota and intestinal health of weaned mice. MB was administered via gavage to 21-day-old weaned mice. Samples of small intestinal and ileal contents were collected on day 1, day 7, and day 21 post-administration. Seven days of MB administration enhanced the mucin layer and morphological structure of the intestine and the integrity of the intestinal brush border. Both MB and sodium butyrate (SB) accelerated tight junction development. Compared to SB, MB modulated intestinal T cells in a distinct manner. MB increased the ratio of Treg cells in the small intestine upon the cessation of weaning. After 21 days of MB administration, enhancement of the villus structure of the ileum was observed. MB increased the proportion of Th17 cells in the ileum. MB facilitated the transition of the small intestinal microbiota toward an adult microbial community structure and enhanced the complexity of the microbial community structure. An increase in Th17 cells enhanced intestinal barrier function. The regulatory effect of MB on Th17 cells may occur through the intestinal microbiota. Therefore, MB can potentially be used to promote intestinal barrier function, especially for weaning animals, with promising application prospects.

Effects of Excess Dietary Fluoride on Serum Biochemical Indices, Egg Quality, and Concentrations of Fluoride in Soft Organs, Eggs, and Serum of Laying Hens.

This study was conducted to investigate the effects of excess dietary fluoride (F) on serum biochemical indices, egg quality, and concentrations of F in soft tissues, eggs, and serum of laying hens. Commercial laying hens (n = 576, 51 weeks of age) were randomly allotted to 6 treatments with 6 replicates of 16 birds. The basal diets contained fluorine inclusions at a level of 16 mg/kg, and graded sodium fluoride was added to the basal diet to achieve fluorine inclusions, respectively, at a level of 200, 400, 600, 800, and 1000 mg/kg in the experimental diets. Dietary F levels at 600, 800, and 1000 mg/kg decreased (P < 0.05) albumin height and yolk color, while eggshell strength and eggshell thickness significantly decreased at 800 and 1000 mg/kg, respectively, compared with the control group. Fluoride concentrations in eggshell, albumin, yolk, liver, kidney, ovary, and oviduct responded to dietary F levels positively, and F concentrations in eggshell were the highest. Fluorine concentrations in albumin and yolk increased with the feeding time at the same dietary F levels (P < 0.05). Dietary F level at 400 mg/kg increased serum calcium level and activity of glutamic oxalacetic transaminase (P < 0.05). In conclusion, dietary F levels at 600 mg/kg decreased albumin height and yolk color, while eggshell strength and eggshell thickness significantly decreased at 800 and 1000 mg/kg, respectively. F concentrations in soft tissues, albumin, yolk, and eggshell of layers had a positive correlation with dietary F levels. By disturbing Ca and phosphorus metabolism, dietary F levels affected the formation of eggshell, reducing eggshell strength and eggshell thickness.