No abstract

The study compared the effect of dietary supplementation with an inorganic or organic source of zinc (Zn) on mucin 2 (MUC-2) and IgA gene expression, the cytokines IL-17 and TGF-β4 and the secretory IgA content (sIgA) in broiler jejunum. One-day-old chickens were fed an unsupplemented basal diet (BD) or the same BD supplemented with 30 or 70 mg/kg of added Zn from ZnSO 4 ·H 2 O or Zn chelate of glycine hydrate for 40 days. The highly expressed MUC-2 and IgA genes were observed in both groups supplemented with the low-dose Zn sources (30 mg/kg). A higher sIgA concentration was observed in both the ZnSO 4 groups and the glycine-zinc/30 mg group. Our data indicate that the organic Zn chelate has better availability than the inorganic Zn source, and the low-dose Zn diets proved to be more beneficial to the maintenance of intestinal immune homeostasis. ARTICLE HISTORY

The concentration of secretory IgA (sIgA) in intestine flush and solid organs (spleen, bursa) in chickens pretreated with probiotic strain Enterococcus faecium AL41 (EF) and challenged with Salmonella Enteritidis PT4 (SE) was assessed. Forty 1-day-old chickens Cobb 500 were divided into four groups: control, EFAL41, SE and combined EFAL41+SE. The increased concentration of sIgA was determined on day 4 after salmonella infection in the intestine flush in EFAL41group. In combined EFAL41+SE group significant increase of sIgA in the intestine flush was found 7 days postinfection. Pre-treatment of chickens with E. faecium AL41 also showed beneficial effect in bursa in EFAL41 and EFAL41+SE groups. In spleen, total IgA was increased only in SE group. The results demonstrated positive effect of E. faecium AL41 on IgA production in chickens' intestine and solid organs after S. Enteritidis PT4 challenge. Validity of method using for IgA evaluation in solid organ was proved.

The mRNA expression of interleukin (IL)-1β, LITAF, iNOS, macrophage inflammatory protein (MIP1-ß), and K60 were examined in peripheral blood mononuclear cells (PMBCs). The PMBCs were isolated from the chicken blood and in vitro exposed to the probiotic strains E. faecium AL41, E. faecium H31, L. fermentum AD1, and infected with Salmonella enterica serovar Enteritidis (SE147). The PMBCs were evaluated for mRNA expression levels at 24 h and 48 h post infection (p.i.) using the reverse transcriptase polymerase chain reaction (RT-PCR). The level of expression of IL-1ß and MIP1-ß was upregulated (P < 0. 001) in the EFAL41+SE (S. Enteritidis + E. faecium AL41) group 48 h p.i. compared to 24 h p.i. Similarly, expression of LITAF was upregulated (P < 0.001) in the EFAL41 + SE group compared to the control (C -no infected) and S. Enteritidis (SE) group 48 h p.i. In PMBCs treated with E. faecium H31 and S. Enteritidis expression of IL-1ß (P < 0.01) and chemokines K60 and MIP1-ß was upregulated (P < 0.001) in the EFH31 + SE group 24 h p.i. The iNOS showed upregulated expression (P < 0.001) in the EFAL41 + SE group compared to the control 24 h p.i. and to the C and SE groups 48 h p.i. The results showed that E. faecium AL41 demonstrated the highest immunostimulatory effect on expression of selected cytokines by chicken PMBCs after Salmonella infection. It is supposed that the differences in cytokine induction within SE groups are related to lymphocytes isolated from different animals. mRNA, RT-PCR, immune system, Enterococcus faecium, in vitro

No abstract