Assessing Metschnikowia pulcherrima as a potential probiotic yeast for animal feed

In response to escalating antimicrobial resistance fuelled by their extensive use in livestock farming, this study explores alternative strategies in animal health management. We investigated the probiotic potential of Metschnikowia pulcherrima strains 4 × 3, DH5, ICS1, and QRI1 for their suitability in poultry environments. Our research demonstrated that previously discovered antimicrobial M. pulcherrima strains exhibit promising probiotic behaviours, including biofilm production, auto-aggregation, cell surface hydrophobicity (CSH), adhesion to Caco-2 cells, antioxidant capacity, and resilience to gastric stresses. Notable findings include DH5 exhibiting the highest biofilm formation, 4 × 3 and DH5 showing rapid auto-aggregation, 4 × 3 and ICS1 displaying high CSH, and all strains demonstrating considerable adherence to Caco-2 cells. 4 × 3 also exhibited exceptional bile tolerance, while ICS1 showed robust survival under simulated gastrointestinal conditions. These traits suggest M. pulcherrima's capacity to colonize the poultry gastrointestinal tract, promote animal health, and support more sustainable livestock practices as a potential alternative to conventional antibiotics.