Impact of dietary manganese on intestinal barrier and inflammatory response in broilers challenged with Salmonella Typhimurium

Growing concern for public health and food safety has prompted a special interest in developing nutritional strategies for removing waterborne and foodborne pathogens, including Salmonella. Strong links between manganese (Mn) and intestinal barrier or immune function hint that dietary Mn supplementation is likely to be a promising approach to limit the loads of pathogens in broilers. Here, we provide evidence that Salmonella Typhimurium (S. Typhimurium, 4 × 108 CFUs) challenge-induced intestinal injury along with systemic Mn redistribution in broilers. Further examining of the effect of dietary Mn treatments (a basal diet plus additional 0, 40, or 100 mg Mn/kg for corresponding to Mn-deficient, control, or Mn-surfeit diet, respectively) on intestinal barrier and inflammation status of broilers infected with S. Typhimurium revealed that birds fed the control and Mn-surfeit diets exhibited improved intestinal tight junctions and microbiota composition. Even without Salmonella infection, dietary Mn deficiency alone increased intestinal permeability by impairing intestinal tight junctions. In addition, when fed the control and Mn-surfeit diets, birds showed decreased Salmonella burdens in cecal content and spleen, with a concomitant increase in inflammatory cytokine levels in spleen. Furthermore, the dietary Mn-supplementation-mediated induction of cytokine production was probably associated with the nuclear factor kappa-B (NF-κB)/hydrogen peroxide (H2O2) pathway, as judged by the enhanced manganese superoxide dismutase activity and the increased H2O2 level in mitochondria, together with the increased mRNA level of NF-κB in spleen. Ingenuity-pathway analysis indicated that acute-phase response pathways, T helper type 1 pathway, and dendritic cell maturation were significantly activated by the dietary Mn supplementation. Our data suggest that dietary Mn supplementation could enhance intestinal barrier and splenic inflammatory response to fight against Salmonella infection in broilers

Polystyrene microplastics enhanced copper-induced acute immunotoxicity in red swamp crayfish (Procambarus clarkii)

Microplastic pollution has attracted a lot of attention in recent years. Not only can it be ingested by animals, but it can easily become a carrier of other pollutants, forming a composite pollutant with potentially toxic effects on organisms. We investigated the effect of Cu on the accumulation of polystyrene microplastics (PS) in the gills of Procambarus clarkii and whether PS exacerbated the immune toxicity of Cu to P. clarkii were exposed to Cu, PS and PS+Cu for 48 h, the accumulation of PS in gill and hepatopancreas immune and antioxidant indices were analyzed. The objective was to investigate the toxic effects of Ps and Cu compound pollutants on P. clarkii and whether the accumulated pollutants would cause food safety problems. The results showed that microplastic particles adhered to each other and aggregated in the PS+Cu group, and the number of microplastic particles in gill in the PS+Cu group was significantly lower than that in the PS group. Compared with the other two treatment groups, SOD, CAT, GPx activities and MDA content increased significantly in the PS+Cu group and were relatively delayed. At 12 h, 24 h, 36 h and 48 h, the SOD mRNA expression levels in the PS+Cu group were all significantly lower than those in the Cu group (P < 0.05). At 24 h and 48 h, CAT mRNA expression in the PS+Cu group was significantly higher than that in the Cu group (P < 0.05). Crustin 4 mRNA expressions in the PS+Cu group was significantly higher than that in the Cu group at 12 h and 36 h (P < 0.05). The results demonstrate that the PS and Cu compound reduced the accumulation of microplastic particles in the gill. PS particles delayed Cu entry into P. clarkii for a short time (12 h) and reduced the toxic effect, but with the increase of exposure time (24 h and 48 h), the toxic effect of PS and Cu complexes on P. clarkii increases, and the large accumulation of PS and Cu complexes may cause food safety problems

Effects of Maternal and Progeny Dietary Vitamin Regimens on the Performance of Ducklings

This study evaluated the interaction effect of maternal and progeny vitamin regimens on the performance of ducklings. At 38 weeks of age, 780 female and 156 male duck breeders were fed either regular or high vitamin premix diet (maternal high premix had higher levels of all vitamins except K3 than maternal regular premix) for 16 weeks. Ducklings hatched from eggs laid at the end of the duck breeder trial were kept separate according to maternal treatment and were fed 2 levels of vitamin premix (NRC and high, progeny high premix had higher levels of all vitamins except biotin than progeny NRC premix) for 35 days. Body weight (P&lt;0.001) and tibia ash (P=0.033) of 1-day-old ducklings and serum total superoxide dismutase activity of 14-day-old ducklings (P=0.027) were increased by maternal high vitamin premix. Progeny high vitamin premix increased body weight (14 days, P=0.019; 35 days, P=0.034), body weight gain (1–14 days, P=0.021; 1–35 days, P=0.034), gain:feed ratio (1–14 days, P&lt;0.001), feed intake (15–35 days, P=0.037), serum total antioxidant capacity (14 days, P=0.048; 35 days, P=0.047), and serum calcium (14 days, P=0.007), and decreased serum malondialdehyde (14 days, P=0.038; 35 days, P=0.031) of ducklings. Maternal vitamin premix–progeny vitamin premix interaction significantly affected body weight (14 days, P=0.029), body weight gain (1–14 days, P=0.029), and feed intake (1–14 days, P=0.018) of progeny ducklings. Briefly, progeny NRC premix decreased the growth performance (days 1–14) of ducklings from maternal regular vitamin group, but not duckling from maternal high vitamin group. The results demonstrate a shortcoming of current vitamin recommendations for ducklings and suggest that the vitamin needs of starter ducklings can be met by either maternal or progeny vitamin supplementation

Histological Lesions, Cell Cycle Arrest, Apoptosis and T Cell Subsets Changes of Spleen in Chicken Fed Aflatoxin-contaminated Corn

The purpose of this study was to evaluate the effects of corn naturally contaminated with aflatoxin B1 and aflatoxin B2 on pathological lesions, apoptosis, cell cycle phases and T lymphocyte subsets of spleen, and to provide an experimental basis for understanding the mechanism of aflatoxin-induced immunosuppression. A total of 900 COBB500 male broilers were randomly allocated into five groups with six replicates per group and 30 birds per replicate. The experiment lasted for 6 weeks and the five dietary treatments consisted of control, 25% contaminated corn, 50% contaminated corn, 75% contaminated corn and 100% contaminated corn groups. The histopathological spleen lesions from the contaminated corn groups was characterized as congestion of red pulp, increased necrotic cells and vacuoles in the splenic corpuscle and periarterial lymphatic sheath. The contaminated corn intake significantly increased relative weight of spleen, percentages of apoptotic splenocytes, induced cell cycle arrest of splenocytes, increased the percentages of CD3+CD8+ T cells and decreased the ratios of CD3+CD4+ to CD3+CD8+. The results suggest that AFB-induced immunosuppression maybe closely related to the lesions of spleen

Effects of Supplementation of 25-Hydroxyvitamin D₃ as a Vitamin D₃ Substitute on Performance, Bone Traits, and Egg Quality of Laying Hens from 1 Day to 72 Weeks of Age

This experiment was conducted to explore the effect of long-term supplementation of 25-hydroxyvitamin D3 (25-OHD) as a vitamin D3 (VD3) substitute on performance, bone traits, and egg quality of laying hens from 1 day to 72 weeks of age. In total, 900 one-day-old Lohman pullets were randomly allotted into three dietary groups (three treatments × 15 replicates × 20 birds per replicate): VD3 2800 IU/kg; 25-OHD 69 μg/kg; 25-OHD 125 μg/kg. At the end of the 20th w, five replicates from each group were selected to feed on the same vitamin D diets, as used during the rearing stage (1–20 w) until 72 w. The result showed that the 25-OHD 125 μg/kg treatment had the lowest average daily feed intake (ADFI) at 1–8 or 1–19 w, body weight at 8 w, body weight gain between 1 and 8 w and shank length at 4 w (p p p = 0.002). The 25-OHD 125 μg/kg treatment had a lower tibia strength at 10 w (p = 0.023) and keel length at 10 w (p = 0.046), compared with the 25-OHD 69 μg/kg treatment. However, both 25-OHD 69 and 125 μg/kg treatments had a greater femur strength at 72 w (p = 0.006), compared with the VD3 2800 IU/kg treatment. No difference in laying performance was observed among all treatments. The overall (21–72 w) ADFI in the 25-OHD 125 μg/kg treatment was significantly lower than that in the 25-OHD 69 μg/kg treatment (p = 0.030). At 60 w, the 25-OHD 125 μg/kg treatment had a lower eggshell thickness (p = 0.012) and proportion of eggshell (p = 0.022), compared with the 25-OHD 69 μg/kg treatment. No significant differences in egg quality parameters were observed at 50 and 70 w among treatments. In general, supplementary 2800 IU/kg doses of VD3 at the early stage were sufficient to maintain the bone quality and growth and development of pullets. Feeding birds at a higher 25-OHD level (125 μg/kg) resulted in the reduced ADFI and growth at the rearing period, but the long-term supplementation of 25-OHD as a VD3 substitute improved the bone quality in the late laying period

Effects of dietary nanocrystalline cellulose supplementation on growth performance, carcass traits, intestinal development and lipid metabolism of meat ducks

The influence of nanocrystalline cellulose (NCC) supplementation on growth performance, carcass traits, intestinal development, and lipid metabolism was assessed in 600 one-day-old male meat ducks (Cherry Valley ducks) from 1 to 35 d of age. Diets were supplemented with 0, 200, 500, 800 and 1,500 mg/kg NCC during both the starter (1–14 d) and grower (15–35 d) phases. Each dietary treatment consisted of 8 replicate cages of 15 birds. Supplementation of NCC was associated with dose dependent increases in BW gain and feed intake (P < 0.01) during 1–14 d of age and in BW at 35 d of age. As NCC content increased, the percentage of breast meat weight (P < 0.05) and leg (with bone) weight (P < 0.05) linearly increased, while the percentage of abdominal fat weight (P < 0.01) linearly decreased in ducks at 35 d of age. Supplementation of NCC resulted in a dose-dependent increase in the weight (P < 0.05) and density (P < 0.01) of the cecum. The percentage of total hepatic lipid content (P < 0.01) at 14 d of age and serum triglyceride (TG) concentration (P = 0.052) at 35 d of age linearly decreased with increasing of dietary NCC addition. In conclusion, inclusion of 1,500 mg/kg NCC in feed resulted in the greatest improvements in duck performance, intestinal development and lipid deposition

Oxidized Oils and Oxidized Proteins Induce Apoptosis in Granulosa Cells by Increasing Oxidative Stress in Ovaries of Laying Hens

The storage and preparation of corn for animal feed inevitably lead to lipid and protein peroxidation. Granulosa cells play an important role in follicular development in the ovaries, and hen laying productivity is likely to be dependent on follicle health and number. We hypothesized that oxidized oil and protein induce apoptosis via oxidative stress in laying hen granulosa cells. A sample of 360 38-week-old Lohmann commercial laying hens was used in a 2×2 factorial design for 8 weeks. Dietary treatments included dietary oil (fresh corn oil (FO) or oxidized corn oil (OO)) and corn gluten meal (fresh corn gluten meal (FP) or oxidized corn gluten meal (OP)). Productivity, ovarian histology, granulosa cell apoptosis, and indicators of oxidative stress were evaluated in all groups. Both dietary OO and OP decreased egg production and the average daily feed intake (ADFI) of laying hens. Flow cytometry, TUNEL, and real-time PCR revealed that both dietary OO and OP induced granulosa cell apoptosis in prehierarchical and hierarchical follicles. Furthermore, dietary OO and OP caused oxidative stress in prehierarchical and hierarchical follicles, as indicated by the downregulation of antioxidant-related-gene expression. Moreover, forkhead box O1 (FoxO1), extracellular regulated protein kinase (ERK), and c-Jun NH2 kinase (JNK) are involved in potential apoptosis regulation pathways in the granulosa cells of laying hens fed OO and OP, as indicated by the upregulation of FoxO1 expression and downregulation of ERK/JNK expression. These results indicate that OO and OP induce granulosa cell apoptosis via oxidative stress, and the combined use of OO and OP aggravates the adverse effects of oxidative stress in laying hens

The improving effect of soybean isoflavones on ovarian function in older laying hens

ABSTRACT: Emerging evidence suggests an association between estrogen levels and reduced egg-laying performance as the layer became old. Since soy isoflavones (SF) have estrogen-mimic effects, whether it can enhance production performance and ovarian function of older layers is still not known. A total of 160 Lohmann pink layers (66-wk-old) were used in a 2 × 2 factorial design, which included 2 egg-laying levels [low (76.89 ± 1.65%; LOW) and normal (84.96 ± 1.01%; NOR)] and 2 different dietary groups [0 mg/kg SF, 20 mg/kg SF] were used. The results showed the NOR group had higher egg-laying rate, egg mass, and feed efficiency during the all phases (P(laying) < 0.05). The unqualified egg rate was lower in NOR group (9–12 wk, 1–12 wk) (P(laying) < 0.05). Dietary supplementation with SF increased the egg-laying rate and feed efficiency (5–8 wk, 9–12 wk, 1–12 wk), increased egg mass (9–12 wk, 1–12 wk) (P(SF) < 0.05). The NOR layers presented higher eggshell quality (redness, yellowness, brightness, eggshell ratio) at 12 wk (P(laying) < 0.05). Eggshell quality was found to be improved by SF (eggshell strength and eggshell thickness), egg albumen quality (higher albumen height and Haugh unit) at 12 wk (P(SF) < 0.05). Supplementing with SF led to an increase in eggshell strength in LOW group (P(laying*SF) < 0.05). The higher serum lever of glucose (GLU) and lower serum lever of follicle stimulating hormone (FSH) were in NOR group (P(laying) < 0.05). Supplementing SF in diets increased serum of estradiol (E2) and insulin-like growth factors-1 (IGF-1), decreased serum of FSH (P(SF) < 0.05). The NOR layers presented lower estrogen receptor α (ERα), estrogen receptor β (ERβ), B lymphoma 2 associated X protein (Bax), cytochrome c (Cytc), interleukin 6 (IL-6), caspase3, caspase9, IKKα, P50, and P65 expression in the ovary (P(laying) < 0.05). Dietary SF supplementation decreased the anti-Müllerian hormone receptor (AMHR), Bax, caspase3, caspase9, Cytc, IL-6, IKKα, P50, P65 expression in the ovary (P(SF) < 0.05). These findings indicated that layers with NOR group had higher production performance, egg quality, and ovarian function, while dietary supplementation with SF improved production performance and ovarian function by reducing inflammation and apoptosis-related genes expression in ovary

Uptake of Manganese from the Manganese-Lysine Complex in Primary Chicken Intestinal Epithelial Cells

Organic manganese (Mn) sources can replace inorganic Mn as dietary Mn supplements in poultry. To compare the uptake of Mn from the Mn-lysine complex (MnLys) and MnSO4, we first established the primary chicken intestinal epithelial cells (IECs) model and used it to determine Mn uptake. The MnLys increased the uptake of Mn compared to MnSO4. The uptake of Mn decreased in the IECs with Fe addition in the medium regardless of the Mn sources. The MnLys decreased the Mn2+ efflux transporter ferroportin 1 (FPN1) mRNA level but did not influence the Mn2+ influx transporter divalent metal transporter 1 (DMT1) mRNA expression when compared to MnSO4. The results above indicated that the increase of Mn accumulation for MnLys at least partly was due to the decrease of Mn efflux by reduced FPN1 expression. The addition of N-ethylmaleimide, an L-lysine transport system y+ inhibitor, decreased the uptake of Mn from MnLys but did not affect the uptake of Mn from MnSO4. The cycloheximide, as an L-lysine transport system b0,+ activator, increased the uptake of Mn from MnLys, whereas they did not influence the uptake of Mn from MnSO4. The MnLys increased the system y+ members cationic amino acid transporter (CAT) 1 and CAT2, and system b0,+ components rBAT and b0,+AT mRNA expression when compared to MnSO4. These results suggested that the uptake of MnLys complex might be transported by CAT1/2 and system b0,+, which was different from the ionized Mn2+ uptake pathway. In conclusion, the uptake of Mn from MnLys complex not only might be uptake through the ionized Mn2+ pathway, but also appeared to be transported through the CAT1/2 and system b0,+ in primary chicken IECs