Abstract
BackgroundProbiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host, are now accepted as suitable alternatives to antibiotics in the control of animal infections and improving animal production. Lactic acid bacteria (LAB) with remarkable functional properties have been evaluated in different studies as possible probiotic candidates. The purpose of this study was to isolate, characterize and assess the potentials of LAB from poultry gastrointestinal tract as potential poultry probiotics.ResultsPotential LAB probiotics were isolated from broilers, characterized and evaluated for probiotic properties including antagonistic activity (against Escherichia coli, E. coli O157: H7, Enterococcus faecalis, Salmonella Typhimurium, S. Enteritidis and Listeria monocytogenes), survivability in simulated gastric juice, tolerance to phenol and bile salts, adhesion to ileum epithelial cells, auto and co-aggregation, hydrophobicity, α–glucosidase inhibitory activity, and antibiotic susceptibility tests. Most promising LAB strains with excellent probiotic potentials were identified by API 50 CHL and 16S rRNA sequencing as Lactobacillus reuteri I2, Pediococcus acidilactici I5, P. acidilactici I8, P. acidilactici c3, P. pentosaceus I13, and Enterococcus faecium c14. They inhibited all the pathogens tested with zones of inhibition ranging from 12.5 ± 0.71 to 20 ± 0 mm, and competitively excluded (P < 0.05) the pathogens examined while adhering to ileum epithelial cells with viable counts of 3.0 to 6.0 Log CFU/ml. The selected LAB strains also showed significant (P < 0.005) auto and co-aggregation abilities with α-glucosidase inhibitory activity ranging from 12.5 to 92.0%. The antibiotic susceptibility test showed 100.00% resistance of the LAB strains to oxacillin, with multiple antibiotic resistance indices above 0.5.ConclusionThe selected LAB strains are ideal probiotic candidates which can be applied in the field for the improvement of poultry performance and control of pathogens in poultry, hence curtailing further transmission to humans.
Highlights
Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host, are accepted as suitable alternatives to antibiotics in the control of animal infections and improving animal production
Isolation of Lactic acid bacteria (LAB) In total, 57 LAB strains were isolated from the Gastrointestinal tract (GIT) of apparently healthy broiler chickens based on their typical morphological appearance, Gram-positive, catalase and coagulasenegative and non-motile, coccus and rod-shaped characteristics [13]
Wider zones of inhibition were exhibited by LAB isolates against E. coli ranging between 17 ± 0 to 20.0 ± 0 mm while the least zones of inhibition ranging from 12.5 ± 0.71 to 17 ± 0 mm as revealed from this study were recorded against S
Summary
Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host, are accepted as suitable alternatives to antibiotics in the control of animal infections and improving animal production. The reason is that intestinal microbiota is believed to be the largest bacterial reservoir in animals [1] These beneficial microbial strains collectively referred to as probiotics are known to be “live microorganisms that, when administered in adequate amounts, confer a health benefit on the host” [2]. LAB including species of Enterococcus, Lactobacillus, Pediococcus, Streptococcus, Lactococcus, Vagococcus, Leuconostoc, Oenococcus, Weissella, Carnobacterium and Tetragenococcus are natural microflora of both humans and animals GIT [4, 5] They have been reported to possess a broad spectrum of beneficial and health promoting properties which dramatically influences the host microbial intestinal balance and general performance [6, 7]. The effectiveness of LAB strains used as probiotics are species and/or strains
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
