This study was conducted to evaluate the effects of organic trace elements (Cu, Fe, Zn, and Mn) on performance, egg quality, trace elements utilization, and intestinal function in late-phase laying hens. A total of 1,080 laying hens (Hy-line brown, 65 weeks old) were randomly assigned to four treatments with six replications of 45 layers each. The basal diet was prepared without adding exogenous trace elements. The control group was fed with a basal diet supplemented with 600 mg/kg of inorganic trace elements. The three treatment groups were fed basal diets supplemented with 300, 450, and 600 mg/kg organic trace elements (OTE300, 450, and 600), respectively. The results showed that there was no significant difference in growth performance among all treatments. However, OTE450 significantly improved the eggshell strength of laying hens (p < 0.05), but had no significant effects on haugh unit, egg yolk weight, eggshell weight, and eggshell thickness, compared with other groups. Moreover, compared with the control group, OTE450 significantly increased the contents of copper, iron, and zinc in serum (p < 0.05). Meanwhile, all of the trace elements had a lower deposition in the feces in organic trace elements groups (p < 0.05). Histological analysis showed that the addition of organic trace elements could significantly improve the villus height and villus concealment ratio (p < 0.05). In addition, the messenger RNA (mRNA) and protein expressions of divalent metal transporter 1 (DMT1), zinc transporter 1 (ZnT-1), and ferroportin 1 (FPN1) were the highest in the OTE450 group. In conclusion, OTE450 could improve egg quality, intestinal function, and trace element utilization efficiency. Thus, this study provides a theoretical basis for the application of low levels of organic trace elements in laying hens.

This study aimed to investigate the effects of compound non-starch polysaccharide (NSP) enzymes on growth performance, slaughter performance, immune function, and apparent utilization of nutrients in broiler chickens fed a low-metabolizable energy diet. A total of 240 healthy 1-day-old AA broilers (Arbor Acres, 47.2 ± 0.31 g) were randomly divided into four treatment groups, each with six replicate groups and 10 broilers per replicate. The control group was fed a basal diet; the EL-H group was fed the basal diet supplemented with 200 mg/kg compound NSP enzyme, including β-mannanase 5,000 IU/g, β-glucanase 2000 IU/g, xylanase 10,000 IU/g, and cellulase 500 IU/g. The EL-M group was fed the basal diet with 50 kcal/kg metabolizable energy removed, supplemented with 200 mg/kg compound NSP enzyme. Finally, the EL-L group was fed the basal diet with 100 kcal/kg metabolizable energy removed, supplemented with 200 mg/kg compound NSP enzyme. The results showed that feeding with a low-metabolizable energy diet supplemented with compound NSP enzymes did not significantly affect the growth performance of broilers (p > 0.05). Compared with the control group, the abdominal fat rate of broilers in the EL-L group was significantly reduced, and that of broilers in the EL-M group was significantly increased (p < 0.05). Apparent utilization of dry matter, crude protein, and energy in the diet was lower in the control group than in the EL-L group, but significantly higher in the control group than in the EL-H group (p < 0.05). In addition, apparent utilization of crude fiber was significantly increased in the EL-H, EL-M, and EL-L groups compared with the control group (p < 0.05). In conclusion, this experiment showed that the addition of 200 mg/kg compound NSP enzyme enabled maintenance of the normal growth and development of broiler chickens fed a low-metabolizable energy diet (replacing 50–100 kcal/kg metabolizable energy). This study provides a theoretical basis for the application of the compound NSP enzyme in broiler chickens.

Gut health of broiler chickens is essential for production performance. The present study aimed to evaluate the impact of dietary supplementation with potassium diformate (KDF) on growth performance and intestinal health in broiler chickens. A total of 180 Arbor Acres (AA) broiler chickens were randomly allocated into 3 treatments, with 6 replicates, containing 10 chicks in each replicate. The treatment groups were: control group (CON) was fed a basal diet; KDF-4 groups fed the basal diet with 4 g/kg KDF; KDF-8 groups fed the basal diet with 8 g/kg KDF. The experiment period lasted for 42 d. During the starter phase, the ADFI and F/G of broilers in KDF groups were lower (P < 0.05) compared to the CON group. Furthermore, the BW and ADG in KDF-4 group was improved (P<0.05). The treatment groups exhibited a significant increase (P < 0.05) in both ADG and ADFI during the grower and overall phase. Moreover, the F/G in KDF-4 group was lower (P < 0.05) compared to the CON and KDF-8 groups. The semi-eviscerated weight rate (SEWR), eviscerated carcass weight rate (ECWR), pectoral muscle rate (PMR), and leg muscle rate (LMR) of broilers were improved (P < 0.05) in KDF groups. The serum levels of glucose (GLU) and UREA (UA) were significantly higher (P < 0.05) in KDF-8 group. Additionally, the nutrient apparent utilization rate of dry matter (DM), energy (EE), and crude protein (CP) were improved (P < 0.05) in KDF-4 group. The villus height (VH) and villus height to crypt depth ratio (V/C) of duodenum, jejunum, and ileum were higher (P < 0.05) in KDF groups compared to the CON group, while crypt depth (CD) was significantly reduced (P < 0.05). The digestive enzyme activities of lipase (LIP), amylase (AMS), or trypsin (TPS) were significantly enhanced (P < 0.05) in the intestinal chyme, while the total bacterial count, Escherichia coli, Lactobacilli, Bifidobacteria, and Bacillus were reduced (P < 0.05) in the ileum. This study demonstrates that the inclusion of KDF in the diet of broilers leads to improvements in growth, slaughter performance, nutrient utilization rate, and maintenance of intestinal health.

This article aims to investigate the mechanism by which Bacillus amyloliquefaciens alleviates lipopolysaccharide (LPS)-induced intestinal oxidative stress. The study involved two experimental subjects: human colorectal adenocarcinoma (Caco-2) cells and Arbor Acres broiler chickens. The experiment involving two samples was designed with the same treatment groups, specifically the control (CK) group, lipopolysaccharide (LPS) group, Bacillus amyloliquefaciens (JF) group, and JF+LPS group. In the Caco-2 experiment, we administered 2 μg/mL of LPS and 1 × 10⁶ CFU/mL of JF to the LPS and JF groups, respectively. In the broiler experiment, the LPS group (19–21 d) received an abdominal injection of 0.5 mg/kg BW of LPS, whereas the JF group was fed 1 × 10⁷ CFU/g of JF throughout the entire duration of the experiment (1–21 d). The results indicated the following: (1) JF significantly decreased the DPPH free radical clearance rate and hydrogen peroxide levels (p < 0.05). (2) JF significantly enhanced the total antioxidant capacity (T-AOC), superoxide dismutase (SOD), and glutathione peroxidase (GSH Px) activity in Caco-2 cells (p < 0.05), while concurrently reducing malondialdehyde (MDA) content (p < 0.05). (3) Compared to the CK group, JF significantly increased the mRNA expression levels of nuclear factor-erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), SOD, catalase (CAT), GSH-Px, interleukin-4 (IL-4), interleukin-10 (IL-10), Claudin, Occludin1, zonula occludens-1 (ZO-1), and mucin 2 (MUC2) in Caco-2 cells (p < 0.05), while concurrently reducing the mRNA expression of Kelch-like ECH-associated protein 1 (Keap1), tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), and interleukin-8 (IL-8) (p < 0.05). In comparison to the LPS group, the JF+LPS group demonstrated a significant increase in the mRNA expression of Nrf2, SOD, GSH-Px, and IL-4, as well as Occludin1, ZO-1, and MUC2 in Caco-2 cells (p < 0.05), alongside a decrease in the mRNA expression of Keap1, TNF-α, and IL-1β (p < 0.05). (4) In broiler chickens, the JF group significantly elevated the levels of T-AOC, CAT, and GSH-Px in the jejunum while reducing MDA content (p < 0.05). Furthermore, the CAT level in the JF+LPS group was significantly higher than that observed in the LPS group, and the levels of MDA, TNF-α, and IL-1β were significantly decreased (p < 0.05). (5) In comparison to the CK group, the JF group exhibited a significant increase in Nrf2 levels in the jejunum of broiler chickens (p < 0.05). Notably, the mRNA expression levels of IL-4, IL-10, Claudin, Occludin1, ZO-1, and MUC2 were reduced (p < 0.05), while the mRNA expression levels of Keap1, TNF-α, and IL-1β also showed a decrease (p < 0.05). Furthermore, the mRNA expression levels of Nrf2, Occludin1, ZO-1, and MUC2 in the JF+LPS group were significantly elevated compared to those in the LPS group (p < 0.05), whereas the mRNA expression levels of Keap1 and TNF-α were significantly diminished (p < 0.05). In summary, JF can enhance the intestinal oxidative stress response, improve antioxidant capacity and intestinal barrier function, and decrease the expression of inflammatory factors by regulating the Keap1/Nrf2 signaling pathway.

Cottonseed protein concentrate (CPC) has the function of replacing soybean meal to maintain normal animal growth and development. This study involved 180 Arbor Acres (AA) broilers, which were randomly assigned to three different treatments. Each treatment had six replicates, with each replicate consisting of 10 chicks. The control group was fed a basal diet, while the CPC-1 and CPC-2 groups used CPC to replace 25% and 50% of the soybean meal in the basal diet, respectively. The study showed that replacing soybean meal with 25% CPC in broilers’ diets can maintain normal growth, while substituting 50% of soybean meal with CPC negatively affects the growth and development of broiler chickens. Furthermore, the CPC-1 group showed a significant increase in serum total antioxidant capacity, superoxide dismutase enzyme activity, and immunoglobulin content, along with a decrease in malondialdehyde content. Based on the research results mentioned above, it was speculated that CPC has the potential to replace around 25% of soybean meal in broiler feed without causing any negative impact on growth performance. This suggests that CPC could be a viable alternative to soybean meal in broiler diet.

Zanthoxylum bungeanum seed meal (ZBM), a novel plant protein raw material, has shown promising potential in enhancing the growth of broiler chickens as a substitute for soybean meal (SBM) in feed. In the artificial digestive experiment of vitro experiments, the digestibility of ZBM and SBM were assessed using the SDS-III Single Stomach Animal Biometric Digestion System. Subsequently, 180 1-day old AA chicks were divided into three groups for in vivo experiments: corn–soybean-meal-based diet (CON group); ZBM replacing 5% soybean meal in the basal diet (ZBM-1 group); ZBM replacing 10% soybean meal in the basal diet (ZBM-2 group). The experiment period lasted for 42 days. Compared to SBM, ZBM demonstrated higher crude protein content, dry matter digestibility, and extracorporeal digestible protein. Compared with the CON group, the broilers in the ZBM-2 group showed improved ADG and ADFI during the 1–21 d, 22–42 d, and 1–42 d periods (p < 0.05). Furthermore, the ZBM groups exhibited significant increases in slaughter performance compared with the CON group (p < 0.05). The substitution of ZBM for SBM also leads to a significant reduction in serum enzyme indicators (p < 0.05). Additionally, the lipoprotein and total cholesterol of the ZBM groups were significantly lower than those of the CON group (p < 0.05). Substituting SBM with ZBM significantly enhances the activity of superoxide dismutase and the content of immunoglobulin G in broiler serum, while reducing the content of malondildehyde (p < 0.05). The ZBM groups showed significantly higher utilization of dry matter, crude protein, and energy compared with the CON group (p < 0.05). In conclusion, the study confirmed that the substitution of SBM with 5–10% ZBM in broiler diets has a significant positive effect on growth, development, antioxidant capacity, immune function, and nutrient utilization. This study not only provides a theoretical foundation for the utilization of ZBM in broiler diets but also offers an effective approach for reducing reliance on soybean meal.