Background: There has been a significant increase, to epidemic levels, of obese and overweight women of reproductive age, causing impairments to reproductive health. Time-restricted feeding (TRF) including isocaloric intake has shown to be preventive of obesity-related disorders. However, its therapeutic ability to improve the reproductive function of female remains largely unknown. Methods: Here, we investigated the ability of TRF to improve the reproductive function in wild-type and liver-specific FGF21 knockout female mice. To study fertility, a continuous and a short-term fertility test, gonadotropin releasinghormone (GnRH), and Kisspeptin test were performed. Immortalized GnRH neuron was used to examine the direct role of liver fibroblast growth factor 21 (FGF21) on GnRH secretion. Results: We found that TRF rescues female mice from bodyweight gain and glucose intolerance, as well as ovarian follicle loss and dysfunction of estrus cyclicity induced by high-fat diet. Furthermore, the beneficial effects of the TRF regimen on the reproductive performance were also observed in mice fed both chow and high-fat diet. However, those beneficial effects of TRF on metabolism and reproduction were absent in liver-specific FGF21 knockout mice. In vitro, FGF21 directly acted on GnRH neurons to modulate GnRH secretion via extracellular regulated protein kinases (ERK 1/2) pathway. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

A precise understanding of the nutritive value of soybean meal (SBM) for pregnant sow is required for accurate feeding. Hence, we evaluated the nutritive value of 11 SBM samples from different sources for sows during mid and late gestation. In total, 24 mid-gestating sows (parity three; 230.3 ± 12.0 kg at d 37 of gestation) and 24 late-gestating sows (parity three; 238.8 ± 20.9 kg at d 72 of gestation) were assigned to a replicated 12 × 3 Youden square design with 12 diets and three periods. The 12 diets included a corn-based diet and 11 diets containing 25.50% SBMs from different sources. After 5 d adaptation, urine and feces were collected for 5 d. Although the chemical characteristics of SBM varied between samples, no differences were observed in digestible energy (DE), metabolizable energy (ME), apparent total tract digestibility (ATTD) of dry matter, gross energy, crude fiber, and neutral detergent fiber values in SBMs fed to both animal groups. However, de-hulled SBM 4 from Brazil displayed greater ATTD for nitrogen (N) in late-gestating sows (P < 0.05); animals displayed significantly (P < 0.01) greater ME, ME:DE ratio, and N net utilization values when compared with mid-gestating sows. The chemical composition of SBMs can be used to predict DE and ME values. In conclusion, ME, ME:DE ratio, and N net utilization SBM values for late-gestating sows were greater than in mid-gestating sows. Therefore, we should consider differences in ME values for SBMs when formulating diets for sows in mid and late gestation periods.

Background The feed intake of sows during lactation is often lower than their needs. High-fiber feed is usually used during gestation to increase the voluntary feed intake of sows during lactation. However, the mechanism underlying the effect of bulky diets on the appetites of sows during lactation have not been fully clarified. The current study was conducted to determine whether a high-fiber diet during gestation improves lactational feed intake (LFI) of sows by modulating gut microbiota. Methods We selected an appropriate high-fiber diet during gestation and utilized the fecal microbial transplantation (FMT) method to conduct research on the role of the gut microbiota in feed intake regulation of sows during lactation, as follows: high-fiber (HF) diet during gestation (n = 23), low-fiber (LF) diet during gestation (n = 23), and low-fiber diet + HF-FMT (LFM) during gestation (n = 23). Results Compared with the LF, sows in the HF and LFM groups had a higher LFI, while the sows also had higher peptide tyrosine tyrosine and glucagon-like peptide 1 on d 110 of gestation (G110 d). The litter weight gain of piglets during lactation and weaning weight of piglets from LFM group were higher than LF group. Sows given a HF diet had lower Proteobacteria, especially Escherichia-Shigella, on G110 d and higher Lactobacillus, especially Lactobacillus_mucosae_LM1 and Lactobacillus_amylovorus, on d 7 of lactation (L7 d). The abundance of Escherichia-Shigella was reduced by HF-FMT in numerically compared with the LF. In addition, HF and HF-FMT both decreased the perinatal concentrations of proinflammatory factors, such as endotoxin (ET), lipocalin-2 (LCN-2), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β). The concentration of ET and LCN-2 and the abundance of Proteobacteria and Escherichia-Shigella were negatively correlated with the LFI of sows. Conclusion The high abundance of Proteobacteria, especially Escherichia-Shigella of LF sows in late gestation, led to increased endotoxin levels, which result in inflammatory responses and adverse effects on the LFI of sows. Adding HF during gestation reverses this process by increasing the abundance of Lactobacillus, especially Lactobacillus_mucosae_LM1 and Lactobacillus_amylovorus.

The imbalance between energy intake and expenditure in an environment of continuous food availability can lead to metabolic disturbances in the body and increase the risk of obesity and a range of chronic noncommunicable diseases. Intermittent fasting (IF) is one of the most popular nonpharmacological interventions to combat obesity and chronic noncommunicable diseases. The 3 most widely studied IF regimens are alternate-day fasting, time-restricted feeding, and the 5:2 diet. In rodents, IF helps optimize energy metabolism, prevent obesity, promote brain health, improve immune and reproductive function, and delay aging. In humans, IF’s benefits are relevant for the aging global population and for increasing human life expectancy. However, the optimal model of IF remains unclear. In this review, the possible mechanisms of IF are summarized and its possible drawbacks are discussed on the basis of the results of existing research, which provide a new idea for nonpharmaceutical dietary intervention of chronic noncommunicable diseases.

Background The feed intake of sows during lactation is often lower than their needs. High-fiber feed is usually used during gestation to increase the voluntary feed intake of sows during lactation. However, the mechanism underlying the effect of bulky diets on the appetites of sows during lactation have not been fully clarified. The current study was conducted to determine whether a high-fiber diet during gestation improves lactational feed intake (LFI) of sows by modulating gut microbiota. Methods We selected an appropriate high-fiber diet during gestation and utilized the fecal microbial transplantation (FMT) method to conduct research on the role of the gut microbiota in feed intake regulation of sows during lactation, as follows: high-fiber (HF) diet during gestation (n = 23); low-fiber (LF) diet during gestation (n = 23); and low-fiber diet + HF-FMT (LFM) during gestation (n = 23). Results Sows in the HF and LFM groups had a higher LFI and litter weight of piglets at weaning, while the sows also had higher peptide tyrosine tyrosine and glucagon-like peptide 1 on day 110 of gestation (G110d) and day 7 of lactation (L7d). Sows given an HF diet had lower Proteobacteria, especially Escherichia-Shigella, on G110d and higher Lactobacilli, especially Lactobacillus_mucosae_LM1 and Lactobacillus_ amylovorus, on L7d. The enrichment of Escherichia-Shigella was alleviated by HF-FMT. In addition, HF and HF-FMT both decreased the perinatal concentrations of proinflammatory factors, such as endotoxin (ET), lipocalin-2 (LCN-2), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β). The concentration of ET and LCN-2 and the abundance of Proteobacteria and Escherichia-Shigella were negatively correlated with the LFI of sows. Conclusion The excessive enrichment of Proteobacteria, especially Escherichia-Shigella late in gestation, led to increased endotoxin levels, which result in inflammatory responses and adverse effects on the LFI of sows. Adding HF during gestation reverses this process by increasing the abundance of Lactobacilli, especially Lactobacillus_mucosae_LM1 and Lactobacillus_amylovorus.