Probiotic <i>Bacillus</i> Strains Enhance T Cell Responses in Chicken

Abstract

Banning antibiotic growth promotors and other antimicrobials in poultry production due to the increasing antimicrobial resistance leads to increased feeding of potential alternatives such as probiotics. However, the modes of action of those feed additives are not entirely understood. They could act even with a direct effect on the immune system. A previously established animal-related in vitro system using primary cultured peripheral blood mononuclear cells (PBMCs) was applied to investigate the effects of immune-modulating feed additives. Here, the immunomodulation of different preparations of two probiotic Bacillus strains, B. subtilis DSM 32315 (BS), and B. amyloliquefaciens CECT 5940 (BA) was evaluated. The count of T-helper cells and activated T-helper cells increased after treatment in a ratio of 1:3 (PBMCs: Bacillus) with vital BS (CD4+: p p p p p p Bacillus), the count of T-helper cells and activated T-helper cells increased (CD4+: p p Bacillus strains enhanced T cell activation and proliferation, which points towards an immune-modulating effect of both strains on chicken immune cells in vitro. Therefore, we suggest that administering these probiotics can improve the cellular adaptive immune defense in chickens, thereby enabling the prevention and reduction of antimicrobials in chicken farming.

Keywords

• antimicrobial resistance
• immune-modulating feed additives
• probiotics
• chicken
• <i>Bacillus</i> spp.