One of the main problems in the poultry industry is the search for a viable replacement for antibiotic growth promoters. This issue requires a “one health” approach because the uncontrolled use of antibiotics in poultry can lead to the development of antimicrobial resistance, which is a concern not only in animals, but for humans as well. One of the promising ways to overcome this challenge is found in probiotics due to their wide range of features and mechanisms of action for health promotion. Moreover, spore-forming probiotics are suitable for use in the poultry industry because of their unique ability, encapsulation, granting them protection from the harshest conditions and resulting in improved availability for hosts’ organisms. This review summarizes the information on gastrointestinal tract microbiota of poultry and their interaction with commensal and probiotic spore-forming bacteria. One of the most important topics of this review is the absence of uniformity in spore-forming probiotic trials in poultry. In our opinion, this problem can be solved by the creation of standards and checklists for these kinds of trials such as those used for pre-clinical and clinical trials in human medicine. Last but not least, this review covers problems and challenges related to spore-forming probiotic manufacturing.

The oil cakes of essential oil plants were screened for prebiotic properties for further development of prebiotic feeds for livestock animals based on these essential oil plants’ extracts. For screening, a microbiota model of the chicken cecum, which was created on the basis of an artificial intestinal medium, was used. This model renders it possible to simulate conditions close to intestinal ones. Oligofructose, inulin, β-glucan, psyllium seeds, and apple fiber at a concentration of 0.5% were used as substances with known prebiotic properties. The oil cake concentration was 0.5%, 1%, 2%, and 4%. The direct antimicrobial effect of the cakes on intestinal bacteria was also investigated. The ability of the cakes to stimulate a decrease in the pH level by Lactobacillus was studied under conditions close to intestinal ones. It was shown that the cakes of big seed false flax (Camelina sativa), brown mustard (Brassica juncea), and spicate lavender (Lavandula angustifolia) exhibit prebiotic properties in relation to the microbiome of chickens in model experiments. They enhance the acid-forming properties of lactic acid bacteria, thereby lowering the pH of the medium. This leads to a decrease in the number of Enterococcus, Escherichia coli, and lactose-positive bacteria, as well as a complete suppression of Proteus. The optimal oil cake concentrations are 1% and 2%. These oil cakes are promising sources of prebiotics for the development of prebiotic feed for agriculture.

A synbiotic preparation based on two strains of B. licheniformis was developed to reduce the harmful effects of mycotoxins in postharvest products used for cattle feed. The genomes of these strains were sequenced to analyze their potential for producing bioactive secondary metabolites. An optimal substrate was selected from the variety of plant substrates, with soybeans being identified as the optimal choice. Based on the results of experiments conducted on experimental animals for a month, the introduction of a synbiotic preparation leveled the negative effect of mycotoxins on weight gain in heifer calves, bringing it to the level of the control groups. There was also a decrease in the level of alkaline phosphatase in serum to normal values, which may indicate the probiotic effects of the preparation, not associated with the elimination of the effect of mycotoxins. The activity of these strains against mycotoxins correlates with the presence of lactonase genes in their genomes. Antimicrobial and bioactive metabolites, such as lichenicidin and lichenisin synthesized by strains CL 33 and CL 56, also seem to contribute to the probiotic effect. The results of the study open up prospects for the creation of new synbiotic preparations to fight contamination with mycotoxins.