Effect of synbiotics on broilers exposed to subclinical doses of fumonisins and deoxynivalenol.

The objective of this study was to identify the efficacy of a synbiotic containing Bifidobacterium animalis, Pediococcus acidilactici, Enterococcus faecium, and fructooligosaccharides in mitigating the effects of subclinical doses of combined fumonisins (FUM), deoxynivalenol (DON), and zearalenone (ZEN) in broiler chickens. A total of 360 one-day-old Cobb 500 male chicks were randomly allocated to four treatments in a 2 × 2 factorial design with six replicates per treatment (n = 6). The treatments were 1) Control, 2) Mycotoxin-contaminated diet, 3) Synbiotic supplementation (0.05 %, PoultryStar BRO, dsm-firmenich), and 4) Mycotoxin + Synbiotic. The analyzed mycotoxin concentrations in the basal and contaminated diets were 2.4 mg FUM + 1 mg DON + 0.07 mg ZEN and 8.5 mg FUM + 3.8 mg DON + 0.6 mg ZEN per kg of diet, respectively. Data were analyzed by two-way ANOVA. Production performance, intestinal morphology, jejunal tight junction protein expression, splenic and cecal CD4+, CD8+ T cell percentage, cytokine expression, and oxidative stress markers were evaluated. There were no significant interaction between mycotoxin and synbiotic treatments were observed for production performance. However, on day 35, synbiotic supplementation significantly increased body weight gain (BWG) compared with no synbiotic supplementation groups (p < 0.05). Significant interactions between mycotoxin and synbiotic treatments were observed on jejunal crypt depth on d 21, villus length in the jejunum and ileum, occludin mRNA expression, and splenic CD8+ T cell percentage and cytokine expression (TNFα and IFNγ) on d 35 (p < 0.05). In chickens fed mycotoxin-contaminated diets, synbiotic supplementation increased jejunal crypt depth and ileal villus length, restored CD8+ T cell percentages in spleen and cecal tonsils, and downregulated proinflammatory cytokine expression. In conclusion, synbiotic supplementation at 0.05 % alleviated the adverse effects of chronic exposure to subclinical doses of FUM + DON + ZEN by improving growth performance, gut morphology, and immune function in broiler chickens.