Bacillus spp. as probiotics in poultry nutrition

Bacillus spp. hold a clear advantage over other probiotics due to their ability to sporulate and proliferate within the gastrointestinal tract (GIT) of animals.

The use of antibiotic growth promoters (AGPs) in animal  diets has been a cause for concern due to the emergence of antibiotic-resistant bacteria, which are associated with human and animal diseases.This has led to AGP bans in many countries around the globe.

PROBIOTICS

Therefore, probiotics are becoming increasingly popular as considerable safe alternatives to replace and reduce antibiotics as  a viable solution to save the livestock sector, especially for young animals such as broilers and piglets.

Probiotics are defined as a preparation containing known viable or inactivated bacteria and are generally recognized as safe. It is also considered that the administration of probiotics or direct feeding microbes (DFMs) in adequate amounts, confers “health benefits for the host.”

Probiotics occupy an important place due to their beneficial impact on host body weight, growth performance, improved health profile, as well as intestinal immunity through the regulation of metabolism and bacterial composition in this area.

Before a probiotic product can be included in poultry feed, it is essential to assess its stability (viability and growth) under the simulation of harsh gastrointestinal tract (GIT) conditions.

A probiotic must retain less than 1 x 106 CFU g-1, for its inclusion level(Millette et al., 2013).

Probiotics improve digestion and nutrient absorption by inhibiting potentially pathogenic bacteria, regulating intestinal distress (Ding et al., 2021), and modulating the gut microbiota, which plays a critical role in maintaining a beneficial health status.

BACILLUS

Morphologically, Bacillus species  have rod-shaped cells with square or rounded ends between 0.5 x 1.2 to 2.5 x 10 ÿm, which present themselves individually or in chains. The stability of the chains determines the shape of the colony, which may differ from strain to strain.