The effect of multi-strain probiotics as feed additives on performance, immunity, expression of nutrient transporter genes and gut morphometry in broiler chickens.

OBJECTIVE

This study was conducted to investigate the effects of dietary multi-strain probiotic (MSP) (Bacillus coagulans Unique IS2 + Bacillus subtillis UBBS14 + Saccharomyces boulardii Unique 28) on performance, gut morphology and expression of nutrient transporter related genes in broiler chickens.

METHODS

A total of 256 (4×8×8) day-old CARIBRO Vishal commercial broiler chicks of uniform body weight were randomly distributed into four treatments with 8 replicates each and having eight chicks in each replicate. Four dietary treatments were T1 (negative control-basal diet), T2 (positive control-antibiotic bacitracin methylene disalicylate at 20 mg/kg diet), T3 (MSP at 107 colony-forming unit [CFU]/g feed), and T4 (MSP at 108 CFU/g feed).

RESULTS

During 3 to 6 weeks and 0 to 6 weeks, the body weight gain increased significantly (p<0.05) in T3 and T4 groups. The feed intake significantly (p<0.05) reduced from T1 to T3 during 0 to 3 weeks and the feed conversion ratio also significantly (p<0.05) improved in T3 and T4 during 0 to 6 weeks. The humoral and cell mediated immune response and the weight of immune organs were also significantly (p<0.05) improved in T3 and T4. However, significant (p<0.05) dietary effects were observed on intestinal histo-morphometry of ileum in T3 followed by T4 and T2. At 14 d post hatch, the relative gene expression of glucose transporter (GLUT5), sodium-dependent glucose transporter (SGLT1) and peptide transporter (PepT1) showed a significant (p<0.05) up-regulating pattern in T2, T3, and T4. Whereas, at 21 d post hatch, the gene expression of SGLT1 and PepT1 was significantly (p<0.05) downregulated in MSP supplemented treatments T3 and T4.

CONCLUSION

The supplementation of MSP at 107 CFU/g diet showed significant effects with improved performance, immune response, gut morphology and expression of nutrient transporter genes. Thus, the MSP could be a suitable alternative to antibiotic growth promoters in chicken diets.