This study was conducted to investigate the effects of Clostridium butyricum addition to diets in late gestation and lactation on the reproductive performance and gut microbiota for sows. A total of 180 healthy Landrace × Yorkshire sows at 90 d of gestation were randomly assigned to one of four groups, with 45 replicates per group, receiving a basal commercial diet (Control, 0% C. butyricum) or diet added with 0.1% C. butyricum (1 × 108 CFU/kg of feed), 0.2% C. butyricum (2 × 108 CFU/kg of feed), 0.4% C. butyricum (4 × 108 CFU/kg of feed), respectively. The experiment was conducted from 90 d of gestation to weaning at 21 d of lactation. The results showed that the interval between piglet born was linearly (P < 0.05) decreased, and the duration of farrowing was significantly (quadratic, P < 0.05) shortened as C. butyricum addition increased. There was a linear (P < 0.05) increase in litter weight at weaning and litter weight gain. The concentrations of IgG and IgM in colostrum, and IgM in milk were linearly increased (P < 0.05) as C. butyricum addition. Serum MDA concentrations of sows at parturition and 14 d in lactation, and piglets at 14 and 21 d of age were linearly (P < 0.05) decreased, respectively. The serum total antioxidant capacity concentrations of sows at parturition and 14 and 21 d in lactation, and piglets at 14 and 21 d of age were linearly (P < 0.05) increased as C. butyricum addition, respectively. There was a linear decrease in the serum endotoxin concentration of sows on 21 d in lactation (P < 0.05). The serum cortisol concentrations of piglets at 14 and 21 d of age were both significantly (quadratic, P < 0.05) decreased. The 0.2% C. butyricum increased the relative abundance of Bacteroidetes (P = 0.016) at phylum level, Prevotellaceae_NK3B31_group, Prevotella_1, Prevotellaceae_UCG-003, Prevotella_9, Alloprevotella (P < 0.05) at genus level, and decreased the relative abundance of Proteobacteria, Gemmatimonadetes, Actinobacteria (P < 0.001) at phylum level, and Clostridium_sensu_stricto_1, Streptococcus, Escheruchia-Shigella, Sphingomonas, Succinivibrio (P < 0.05) at genus level and Firmicutes/Bacteroidetes ratio (P = 0.020). In conclusion, the present research indicated that dietary addition with C. butyricum could shorten the duration of farrowing and enhance the growth performance of suckling piglets. Moreover, 0.2% C. butyricum administration to sows changed the composition of intestinal microbiota, especially increased the relative abundance of Prevotella.

We investigated the effects of dietary fiber (DF) supplementation in normal or low crude protein (CP) diets on reproductive performance and nitrogen (N) utilization in primiparous gilts. In total, 77 Landrace × Yorkshire (LY) pregnant gilts were randomly allocated to four dietary treatments in a 2 × 2 factorial design. The groups comprised 1) equal intake of normal CP (12.82% and 0.61% total lysine), 2) low CP (10.53% and 0.61% total lysine), and 3) with or 4) without DF supplementation (cellulose, inulin, and pectin in a 34:10:1 ratio). A low-protein diet during gestation significantly reduced daily weight gain from days 91–110 of pregnancy (-162.5 g/d, P = 0.004). From N balance trials conducted at days 35–38, 65–68, and 95–98 of pregnancy, DF addition increased fecal N excretion at days 65–68 (+24.1%) and 95–98 (+13.8%) of pregnancy (P &lt; 0.05), but reduced urinary N excretion (P &lt; 0.05), resulting in greater N retention at each gestational stage. DF increased fecal microbial protein levels and excretion during gestation. A low CP diet also reduced urinary N excretion at different gestational stages. An in vitro fermentation trial on culture media with non-protein N urea and ammonium bicarbonate (NH4HCO3) as the only N sources revealed that microbiota derived from feces of gestating gilts fed the high DF diet exhibited a greater capacity to convert non-protein N to microbial protein. Microbial fecal diversity, as measured by 16S rRNA sequencing, revealed significant changes from DF, but not CP diets. Gilts fed a low CP diet had a higher number of stillbirths (+ 0.83 per litter, P = 0.046) and a lower piglet birth weight (1.52 kg vs. 1.37 kg, P = 0.006), regardless of DF levels. Collectively, DF supplementation to gestation diets shifted N excretion from urine to feces in the form of microbial protein, suggesting that the microbiota had a putative role in controlling N utilization from DF. Additionally, a low-protein diet during gestation negatively affected the litter performance of gilts.

Background Replacement gilts are typically fed ad libitum, whereas emerging evidence from human and rodent studies has revealed that time-restricted access to food has health benefits. The objective of this study was to investigate the effect of meal frequency on the metabolic status and ovarian follicular development in gilts. Methods A total of 36 gilts (Landrace × Yorkshire) with an age of 150±3 d and a body weight of 77.6±3.8 kg were randomly allocated into one of three groups (n = 12 in each group), and based on the group allocation, the gilts were fed at a frequency of one meal (T1), two meals (T2), or six meals per day (T6) for 14 consecutive weeks. The effects of the meal frequency on growth preference, nutrient utilization, short-chain fatty acid production by gut microbial, the post-meal dynamics in the metabolic status, reproductive hormone secretions, and ovarian follicular development in the gilts were measured. Results The gilts in the T1 group presented a higher average daily gain (+ 48 g/d, P < 0.05) and a higher body weight (+ 4.9 kg, P < 0.05) than those in the T6 group. The meal frequency had no effect on the apparent digestibility of dry matter, crude protein, ether extract, ash, and gross energy, with the exception that the T1 gilts exhibited a greater NDF digestibility than the T6 gilts (P < 0.05). The nitrogen balance analysis revealed that the T1 gilts presented decreased urine excretion of nitrogen (− 8.17 g/d, P < 0.05) and higher nitrogen retention (+ 9.81 g/d, P < 0.05), and thus exhibited higher nitrogen utilization than the T6 gilts. The time-course dynamics of glucose, α-amino nitrogen, urea, lactate, and insulin levels in serum revealed that the T1 group exhibited higher utilization of nutrients after a meal than the T2 or T6 gilts. The T1 gilts also had a higher acetate content and SCFAs in feces than the T6 gilts (P < 0.05). The age, body weight and backfat thickness of the gilts at first estrous expression were not affected by the meal frequency, but the gilts in the T1 group had higher levels of serum luteinizing hormone on the 18th day of the 3rd estrus cycle and 17β-estradiol, a larger number of growing follicles and corpora lutea, and higher mRNA expression levels of genes related to follicular development on the 19th day of the 3rd estrus cycle. Conclusions The current findings revealed the benefits of a lower meal frequency equal feed intake on nutrient utilization and reproductive function in replacement gilts, and thus provide new insights into the nutritional strategy for replacement gilts, and the dietary pattern for other mammals, such as humans.

Various studies have evaluated the relationship between cholecalciferol (vitamin D 3 ) and reproductive performance. This study aimed at investigating the effects of maternal D 3 supplementation during gestation on reproductive performance and antioxidant capacities of gilts and their offsprings. Twenty-three Landrace  Yorkshire gilts were randomly allocated into two groups and fed on one of the following two diets during gestation: control diet or D 3 supplemented diet. It was found that D 3 supplementation had a tendency to increase the number of total born and born alive piglets. Moreover, it elevated serum 25-hydroxycholecalciferol concentrations in gilts and newborn piglets. Besides, D 3 supplementation improved the activities of antioxidant enzymes (GSH-Px, T-AOC and T-SOD) in the blood of gilts, umbilical cord and newborn piglets and piglets' liver, while serum malondialdehyde concentrations of gilts and umbilical cord were reduced in the D 3 group. In addition, D 3 supplementation upregulated the expression of antioxidant related genes in the placenta and piglets' liver. In conclusion, D 3 supplementation during gestation might improve antioxidant capacities in gilts, placenta and in newborn piglets. Therefore, D 3 supplementation has the potential to enhance the reproductive performance of gilts. HIGHLIGHTSD 3 supplementation has a significant role in the nutrition of gilts. Maternal D 3 supplementation during gestation increased the number of born and born alive piglets. Maternal D 3 supplementation during gestation improved the antioxidant capacities of gilts, placenta and newborn piglets.

Vitamin D3 (VD3) has been reported to improve the reproductive performance of sow. This study was conducted to investigate the long-term effect of maternal VD3 supplementation during gestation on the...