Selection of Lactobacillus strains from native chicken feces for the fermentation of purple onion (L.) as an antibiotic alternative againstspp. in chickens.

Abstract

BACKGROUND: The increasing prevalence of antibiotic resistance in poultry pathogens necessitates the development of sustainable alternatives to antibiotics. Probiotics, particularlyspp., have shown promise in combating bacterial infections in poultry. Purple onion extract (OE) possesses antibacterial properties and can potentially enhance the probiotic efficacy ofstrains. AIM: This study aimed to develop a biological product based on-fermented OE (LFOE) as a sustainable alternative to antibiotics for the control of-induced diarrhea in poultry. METHODS: strains were isolated from native free-range chicken feces and screened for their antibacterial activity againstNCTC10705 andFC13827, as well as their survival rate in OE. Six promising strains were selected and further characterized for their ability to ferment OE and their co-aggregation ability against the pathogenic bacteria using scanning electron microscopy (SEM). 16S rRNA gene sequencing was performed for bacterial identification. The selected strain was used for fermentation in OE, and the resulting product was freeze-dried into a biological preparation.studies in chicks were conducted to assess the safety and intestinal persistence of LFOE. RESULTS: From an initial pool of 68strains, six promising candidates (1582,WCFS1,JDM1,NCFM,DSM 20509, andLa3) were selected based on their antibacterial activity and high survival rate in OE. SEM confirmed the ability of these strains to ferment OE and co-aggregate with pathogenic bacteria. 16S rRNA gene sequencing confirmed their taxonomic identity as.1582, selected for its superior probiotic properties, was used to ferment LFOE, which proved safe for chicks and demonstrated the strain's ability to survive temporarily in the intestine. CONCLUSION: This study successfully developed a biopreparation based on LFOE as a potential alternative to antibiotics for the control of-induced diarrhea in poultry. However, regular re-supplementation is required to maintain probiotic efficacy due to the transient nature of intestinal colonization.