This study aimed to investigate the effects of different supplementation levels of stevia residues in high-fiber diets on the fecal microorganisms of pregnant sows. Forty-eight first-farrowing Danish Landrace sows with similar weight, age, and due date were randomly divided into four groups. The control group was fed a normal diet (CON; 3.15% crude fiber content), and the treatment groups were supplemented with 20% stevia residue (SRL), 30% stevia residue (SRM), or 40% stevia residue (SRH) stevia residue, with crude fiber content of 7.79%, 9.15%, and 10.68%, respectively. The test period was 135 days, and Illumina Miseq high-throughput sequencing was used to test the fecal bacteria of the pregnant sows on day 56. Compared to the control group, species diversity was greater in the 30% stevia residue group. At the phylum level, Firmicutes and Spirochaetes had the greatest relative abundances; Firmicutes was most abundant in the SRM group, and Spirochaetes was most abundant in the CON group. At the genus level, Lactobacillus, Streptococcus, and Lachnospiraceae_XPB1014_group, and Treponema_2 had the highest relative abundances in the stevia-residue treatments. Among them, Lactobacillus and Treponema_2 were more abundant in SRL, Streptococcus was more abundant in SRH, and Lachnospiraceae_XPB1014_group was more abundant in SRM. Linear discriminant analysis effect size (LEfSe) showed that the bacterial species differed among the stevia residue treatments. SRL mainly included g__Lactobacillus and g__Romboutsi, SRM mainly included g__Lachnospiraceae_XPB1014_group and g__Ruminococcaceae_UCG_014, SRH mainly included g__Streptococcus, and CON mainly included g__Treponema_2, f__Clostridiaceae_1, g__norank_f__Muribaculaceae, and g__norank_f__p_251_o5. Stevia-residue supplementation significantly increased the abundance of beneficial bacteria, such as g__Lachnospiraceae_XPB1014_group, g__Christensenellaceae_R-7_group, and g__Ruminococcaceae_UCG-005 (p < 0.05), and significantly reduced the abundance of harmful bacteria, such as Treponema_2 (p < 0.05). Moreover, compared with the control group, the stevia-residues treatment groups reduced the feed cost 8.33%, 12.50%, and 13.33% per sow per day, respectively. In conclusion, high-fiber diets can improve the intestinal balance and evenness index of the intestinal flora in pregnant sows, promote the relative abundance of beneficial bacteria, reduce the relative abundance of harmful bacteria, and reduce feed cost. The optimal supplementation level of the stevia residue was found to be 30%.

The current study aims to assess the effects of coated sodium butyrate (CSB) on the weaning transition of White King pigeons. A total of 336 1-month-old White King pigeons were assigned randomly to four groups, including the Control group fed basal health sandand without CSB and test groups fed the basal health sand with 0.1%, 0.2%, and 0.4% CSB, respectively. The results showed that, compared with the Control group, the average daily feed intake (ADFI) was significantly increased in the 0.1% and 0.2% CSB groups (p < 0.05). The 0.1% CSB group exhibited a higher immune organ index (IOI) than the Control group (p < 0.05). The total protein (TP) and albumin (ALB) levels in the 0.1% CSB and 0.4% CSB groups significantly increased compared with the Control group (p < 0.05). In contrast, the 0.2% CSB group exhibited lower serum ALB, TP, and total cholesterol (TC) levels; TNF-α and IL-6 concentrations were reduced compared with the other groups (p < 0.05), and the 0.4% CSB group showed significantly increased serum TNF-α, IL-6, and D-lactic acid levels (p < 0.05). The ratio of villus height to crypt depth (VH/CD) of the jejunum (p < 0.05) was significantly increased in the 0.2% CSB group. In addition, the CD and VH/CD of the ileum were significantly increased in the 0.1% CSB group (p < 0.05). Firmicutes was the predominant phylum across all treatment groups, while Bacteroidota showed a more sensitive response to CSB supplementation. The 0.1% CSB group showed a significant enrichment of Oscillospiraceae and Muribaculaceae, fiber-fermenting, SCFA-producing taxa, Enterobacterales and Klebsiella, suggesting CSB-mediated alterations in luminal oxygen tension that favor the coexistence of facultative and obligate anaerobic taxa. Collectively, these data revealed that CSB supplementation efficiently improves growth performance and intestinal health of weaning pigeons by ameliorating the intestinal environment.

This study aimed to elucidate the effects of different fattening stages on slaughtering performance, meat quality, muscle fiber characteristics, connective tissue properties, and intramuscular fat deposition in Yanbian cattle. A total of 40 eighteen-month-old castrated male Yanbian cattle were raised together under identical conditions. At 24, 28, 32, and 36 months of age, 10 animals were randomly selected and slaughtered. Increased fattening periods, slaughter performance of Yanbian cattle improved steadily, carcass weight and meat weight increased significantly (p < 0.05). Dressing percentage and lean meat percentage reached their maxima at 32 months, which were 60.09% and 46.96% respectively. Cooking loss and centrifugal loss decreased with fattening time (p < 0.05), with the 32- and 36-month-old groups showing the best water-holding capacity. Intramuscular fat content increased significantly during fattening (p < 0.05), with no significant difference between the 32- and 36-month-old groups (p > 0.05). However, Warner–Bratzler shear force (WBSF) was significantly higher at 32 and 36 months than at 24 and 28 months (p < 0.05), indicating reduced tenderness with prolonged fattening. The endomysial collagen network at 32 months maintained a compact yet filamentous structure, whereas by 36 months it had transformed into a dense sheet-like configuration. In conclusion, fattening to 32 months achieves a compromise among marbling, collagen maturity, water-holding capacity, slaughtering efficiency, and the onset of increased toughness. Therefore, 32 months is recommended as the fattening endpoint when balancing meat production and quality traits.