Wenjing Tao

Effects of copper-loaded chitosan nanoparticles on growth and immunity in broilers

Effects of dietary copper-loaded chitosan nanoparticle (CNP-Cu) supplementation on growth performance, hematological and immunological characteristics, and the cecal microbiota in broilers were investigated. Three hundred healthy Avian × Avian (1-d-old) broilers were randomly assigned into 5 dietary groups (20 birds per replicate with 3 replicates per group). Birds were fed with 0 (the control group), 50, 100, 150 mg/kg of CNP-Cu and 50 mg/kg chlorotetracycline (CTC, a positive control group) for 42 d. Results indicated that supplemental CNP-Cu could improve growth performance, affect the immune system, enhance protein synthesis, and be beneficial to cecal microbiota of Avian broilers, especially the dietary supplementation with 100 mg/kg of CNP-Cu. Supplementation with 100 mg/kg of CNP-Cu increased the average daily gain(P < 0.05) and the contents of IgA (P < 0.01), IgG (P < 0.01), IgM (P < 0.01), complement C3 (P < 0.05), and complement C4 (P < 0.05). Thymus, spleen, and bursa of Fabricus indexes and the populations of Lactobacillus and Bifidobacterium in cecal digesta were increased (P < 0.05) by 100 mg/kg of CNP-Cu supplementation, and the population of coliforms was decreased (P < 0.05). Dietary supplementation with 100 mg/kg of CNP-Cu increased (P < 0.05) concentrations of serum total protein and albumin, and decreased (P < 0.05) the content of urea nitrogen in serum. Effects of dietary supplementation with 100 mg/kg of CNP-Cu were similar to 50 mg/kg of CTC supplementation. These results may indicate that CNP-Cu could be a new substitute for CTC in dietary supplementation.

Effects of dietary zinc oxide nanoparticles supplementation on growth performance, zinc status, intestinal morphology, microflora population, and immune response in weaned pigs: Effects of dietary zinc oxide nanoparticles on weaned pigs

BACKGROUND This study evaluated the effects of dietary zinc oxide nanoparticles (nano-ZnOs) on growth performance, zinc status, intestinal morphology, microflora population, and immune response in weaned piglets. A total of 150 weaned piglets (9.37 ± 0.48 kg) were randomly allotted to five dietary treatments and fed with a basal diet (control), or the basal diet supplemented with nano-ZnOs at 150, 300, or 450 mg kg-1 , and 3000 mg kg-1 ZnO for 21 days. After a feeding test, six pigs from the control, 450 mg kg-1 nano-ZnOs and 3000 mg kg-1 ZnO groups were slaughtered. RESULTS Compared with the control, dietary supplements of nano-ZnOs and ZnO could improve (P < 0.05) average daily weight gain (ADG), average daily feed intake (ADFI), and villus height to crypt depth ratio in the duodenum and jejunum, and decrease (P < 0.05) diarrhea incidence. Zinc retention in the serum, heart, liver, spleen and kidney of pigs supplemented with nano-ZnOs and ZnO was increased (P < 0.05). Nano-ZnOs decreased (P < 0.05) the zinc excretion compared with conventional ZnO. Lower Escherichia coli counts in the cecum, colon, and rectum were observed (P < 0.05) in the nano-ZnOs group compared with the other groups. Compared with the control, ZnO and nano-ZnOs increased (P < 0.05) the serum concentration of IgA, IL-6, and TNF-α, and decreased (P < 0.05) the concentration of IgM. CONCLUSION These results indicated that low doses of nano-ZnOs can have beneficial effects on growth performance, intestinal morphology and microflora, and immunity in weanling pigs, which are similar to the effects of pharmacological dosages of conventional ZnO. Nano-ZnOs may reduce mineral excretion, which may reduce environmental challenges.

Clostridium Tyrobutyricum Protect Intestinal Barrier Function from LPS-Induced Apoptosis via P38/JNK Signaling Pathway in IPEC-J2 Cells

Background/Aims: The intestinal mucosa forms a physical and metabolic barrier against the diffusion of pathogens, toxins, and allergens from the lumen into the circulatory system. Early weaning, a critical phase in swine production, can compromise intestinal barrier function through mucosal damage and alteration of tight junction integrity Maintenance of intestinal barrier function plays a pivotal role in optimum gastrointestinal health. In this study, we investigated the effects of Clostridium tyrobutyricum (C.t) on intestinal barrier dysfunction induced by lipopolysaccharide (LPS) and the underlying mechanisms involved in intestinal barrier protection. Methods: A Transwell model of IPEC-J2 cells was used to imitate the intestinal barrier. Fluorescence microscopy and flow cytometry were used to evaluate apoptosis. Real-time PCR was used to detect apoptosis-related genes and the downstream genes of the p38/c-Jun N-terminal kinase (JNK) signaling pathways. Western blotting was used to measure the expressions of tight junction proteins and mitogen-activated protein kinases. Results: C.t efficiently maintained trans-epithelium electrical resistance values and intestinal permeability after LPS-induced intestinal barrier disruption. The expressions of tight junction proteins (ZO-1, claudin-1, and occludin) were promoted when IPEC-J2 cells were treated with C.t. Fluorescence imaging and flow cytometry revealed that C.t qualitatively and quantitatively inhibited LPS-induced cell apoptosis. C.t also increased the relative expression of the anti-apoptotic gene Bcl-2 and decreased that of the apoptotic genes Bax and caspase-3/-8. Moreover, the protective effect of C.t on damaged intestinal cell models was associated with suppression of p38 and JNK phosphorylation, negative regulation of the relative expressions of downstream genes including AP-1, ATF-2, ELK-1, and p53, and activation of Stat3 expression. Conclusions: These findings indicate that C.t may promote intestinal integrity, suggesting a novel probiotic effect on intestinal barrier function.