Bacillus Probiotics as Alternatives to In-feed Antibiotics and Its Influence on Growth, Serum Chemistry, Antioxidant Status, Intestinal Histomorphology, and Lesion Scores in Disease-Challenged Broiler Chickens

Abstract

In commercial poultry production, chickens are reared under intensive conditions, which may allow infections to spread quickly. Antibiotics are used at sub-therapeutic doses in livestock and poultry feed to prevent diseases and improve productivity. However, restrictions on the use of antibiotics at sub-therapeutic concentrations in livestock feed due to growing concerns of antimicrobial resistance (AMR), together with antibiotic residues in meat and eggs has prompted poultry researchers and feed producers to look for viable alternatives. Thus, there is increasing interest in developing natural alternatives to in-feed antibiotics to improve chicken productivity and health. Probiotics, specifically from the genus Bacillus have proven to be effective due to their spore-forming capabilities. Furthermore, their ability to withstand heat during feed processing and be stored for a long time without losing viability as well as their potential to function in the acidic medium of the chicken gut, provide them with several advantages over conventional probiotics. Several studies regarding the antimicrobial and antioxidant activities of Bacillus probiotics and their positive impact in chicken nutrition have been documented. Therefore, the present review shields light on the positive effect of Bacillus probiotics as alternatives to in-feed antibiotics on growth performance, serum chemistry, antioxidant status, intestinal histomorphology and lesion scores of disease-challenged broiler chickens and the mechanisms by which they exert their actions. It is concluded that Bacillus probiotics supplementation improve growth, health and productive indices of disease-challenged broiler chickens and can be a good alternative to in-feed antibiotics. However, more studies are required on the effect of Bacillus probiotics supplementation in broiler chickens to maximize productivity and achieve the ultimate goal of stopping the usage of antibiotics at sub-therapeutic doses in broiler chicken feed to enhance performance.

Isolation and in vitro assessment of chicken gut microbes for probiotic potential

“…These limitations include high cost of broilers feed, mortality due to diseases, improper nutrition, lack of disease control programs, poor hatching conditions, improper sanitation, and poor immunity in chickens. Additionally, farmers use antibiotics to reduce enteric illnesses and increase feed conversion ratio (FCR) and body weight gain (BWG) to meet increased demand for poultry products ( Desiere et al, 2018 ; Ogbuewu et al, 2022 ). As a consequence, broiler meat is saturated with carcinogenic hormones and antibiotic growth promoters (AGPs).…”

The Association between Broiler Litter Microbiota and the Supplementation of Bacillus Probiotics in a Leaky Gut Model

“…Probiotics, such as Lactobacillus spp. and Bacillus spp., have been suggested as promising alternatives to antibiotic growth promoters (AGPs) [ 26 , 27 , 28 ]. The present study investigates the litter microbiota of broilers with and without a Bacillus -based probiotic product containing a mix of B. amyloliquefaciens strains in a leaky gut model.…”

Normalization of Deviant Behavior in Muc2+/+ Mice through Dietary Incorporation of Bacillus subtilis Spores

“…Most used probiotic cultures are Bacillus subtilis, Bacillus coagulans, Bacillus licheniformis, Enterococcus faecium, Enterococcus faecalis [19][20][21] . Initially, these microorganisms were developed as an alternative to antibiotics and utilized in agriculture [22][23][24][25] . This experience was so successful that probiotics based on Bacillus spp.…”