Comparative efficacy of a novel Bacillus subtilis-based probiotic and pharmacological zinc oxide on growth performance and gut responses in nursery pigs.

In this study, we assessed the efficacy of a novel Bacillus subtilis probiotic in improving growth performance and gut responses in comparison to pharmacological zinc oxide (ZnO) in nursery pigs. A total of 96 piglets were randomly assigned to four groups: Negative control (NC), Positive control (PC, 3000 mg Zn /kg feed), B.subtilis low dose (BS9-L, 2 × 107 CFU/pig) and B.subtilis high dose (BS9-H, 2 × 109 CFU/pig). Growth performance, diarrhea rate, gut mucosal gene expression and fecal microbial populations were evaluated. B.subtilis administration did not improve piglet bodyweight. BS9-L showed (P < 0.05) higher average daily gain (ADG) in Period 2 (D14-D28). BS9 groups had (P < 0.001) lower feed conversion ratio (FCR) in Period 2 (D14-D28) and overall. Like the ZnO-group, BS9 groups had lower (P < 0.01) diarrhea rate. A significant reduction (P < 0.05) in fecal E. coli, total coliforms, and an increase in lactic acid bacteria and Bacillus spp. in BS9 groups was observed. BS9 group had reduced (P < 0.05) mRNA levels of intestinal IL-8 and higher levels of MUC-1 and occludin and TJP-1 compared to negative control. These findings suggest that probiotic BS9, may promote growth performance, and ameliorate various indicators of intestinal health in piglets. Hence, it may serve as a prospective alternative to ZnO growth promoter in commercial swine production.

Choline supplementation regulates gut microbiome diversity, gut epithelial activity, and the cytokine gene expression in gilts.

Choline is an essential nutrient that is necessary for both fetal development and maintenance of neural function, while its effect on female ovarian development is largely unexplored. Our previous study demonstrated that choline supplementation promotes ovarian follicular development and ovulation, although its underlying mechanism was unclear. To uncover the potential regulation pathway, eighteen female Yorkshire × Landrace gilts were fed with either standard commercial diet (Control group, n = 9) or choline supplemented diet (Choline group, additional 500 mg/kg of control diet, n = 9) from day 90 of age to day 186. At day 186, feces samples were analyzed for effects on the gut microbiome using 16S ribosomal RNA gene V3-V4 region sequencing with Illumina MiSeq, serum samples were analyzed for trimethylamine (TMA) and trimethylamine-N-oxide (TMAO) using HILIC method, and jejunum tissues were analyzed for immune related gene expression using qRT-PCR. Our results show that choline supplementation did not alter the circulating level of TMA and TMAO (P > 0.05), but rather increased gut microbiome alpha diversity (P < 0.05). Beta diversity analysis results showed that the choline diet mainly increased the abundance of Firmicutes, Proteobacteria, and Actinobacteria, but decreased the abundance of Bacteroidetes, Spirochaetes, and Euryarchaeota at the phyla level. Meta-genomic analysis revealed that choline supplementation activated pathways in the gut microbiota associated with steroid hormone biosynthesis and degradation of infertility-causing environmental pollutants (bisphenol, xylene, and dioxins). To further verify the effect of choline on intestinal activity, a porcine intestine cell line (IPEC-J2) was treated with serial concentrations of choline chloride in vitro. Our data demonstrated that choline promoted the proliferation of IPEC-J2 while inhibiting the apoptotic activity. qRT-PCR results showed that choline significantly increased the expression level of Bcl2 in both IPEC-J2 cells and jejunum tissues. The expression of IL-22, a cytokine that has been shown to impact ovarian function, was increased by choline treatment in vitro. Our findings reveal the beneficial effect of choline supplementation on enhancing the gut microbiome composition and intestinal epithelial activity, and offer insights into how these changes may have contributed to the ovarian development-promoting effect we reported in our previous study.

Choline supplementation influences ovarian follicular development.

BACKGROUND: Female infertility is a health issue for both humans and animals and despite developments in medical interventions, there are still some conditions that cannot be treated successfully. It is important to explore other potential therapies or remedies that could improve reproductive health. Choline is an over-the-counter supplement and essential nutrient that has many health benefits. It has been suggested to be beneficial in various aspects of fertility, including fetal development and endocrine disorders like polycystic ovarian syndrome (PCOS). However, choline's impact on ovarian function has not been explored. METHODS: To study the effects of choline on ovarian development, 36 female Yorkshire × Landrace pigs were fed the following four supplemented diets between 90 and 186 days of age: (1) Control (corn and soybean meal-based diet that met estimated nutrient requirements, n = 9); (2) Choline (additional 500 mg choline per 1 kg of control diet, n = 8); (3) Omega-3 (additional 5556 mg Omega-3 per 1 kg control diet by introducing fish oil); (4) Choline + Omega-3 (500 mg choline + 5556 mg Omega-3 per 1 kg control diet). Pigs fed the choline-supplemented diet were compared to the control group and those fed diets supplemented with Omega-3 as fertility-promoting agent. RESULTS: It was found that the number of corpus luteum per ovary in the Choline (16.25 ± 2.88), Omega-3 (10.78 ± 1.71) and Choline + Omega-3 (14.89 ± 2.97) groups were all higher in comparison to that of the control group (5.56 ± 1.72, p < 0.05). The percentage of antral follicles in the Choline + Omega-3 group were higher compared to the control group (p < 0.05). To elucidate the potential molecular mechanism of choline on these improved ovarian phenotypes, the expression of a group of genes that are involved in ovarian development, including cytochrome P450 family 11 subfamily A member 1 (CYP11A1), follicle stimulating hormone receptor (FHSR) and luteinizing hormone receptor (LHR), was analyzed using RT-qPCR. The expression of both LHR and CYP11A1 was significantly upregulated in the choline-supplemented group (p < 0.05), while there are no differences in FSHR expression among all the groups. Additionally, the expression of miR-21, -378, -574, previously found to be important in ovarian function, were examined. Our data showed that miR-574 was upregulated in the Choline group while miR-378 was upregulated in the Choline + Omega-3 group in comparison to the control group (p < 0.05). Further, serum metabolite analysis showed that 1-(5Z, 8Z, 11Z, 14Z, 17Z-eicosapentaenoyl)-sn-glycero-3-phosphocholine, a form of phosphatidylcholine metabolite, was significantly increased in all the treatment groups (p < 0.05), while testosterone was significantly increased in both Omega-3 and Choline + Omega-3 groups (p < 0.05) and tended to be reduced in the choline-supplemented group (p = 0.08) compared to the control group. CONCLUSIONS: Our study demonstrated choline's influence on ovarian function in vivo, and offered insights into the mechanisms behind its positive effect on ovarian development phenotype.