Abstract

Salmonella serovars are responsible for a variety of acute and chronic diseases in poultry. Leuconostoc mesenteroides probiotic can exert antimicrobial activity by producing diverse fermentative metabolites with bactericidal or bacteriostatic activities such as lactic and acetic acids, fatty acids, hydrogen peroxide or diacetyl and antimicrobial proteins such as bacteriocins and peptidoglycan hydrolase enzymes. This trial aimed at adding novel therapy against virulent and multidrug resistance avian salmonellosis. The incidence of salmonellae in this study was 20% with high recovery rate from liver followed by yolk sac and the most common serovars were Salmonella Kentukey, Salmonella Infantis and Salmonella Enteritidis whose antibiogram showed high resistance to ampicillin, nalidexic acid, sulphamethoxasole + trimethoprim and tetracyclines. Selected virulent and multidrug resistant Salmonella serovars were exposed to probiotic mixture consisting of L. mesenteroides and zinc nanoparticles in different concentration to detect the antibacterial effect against different Salmonella serovars as novel therapy for avian salmonellosis. This study revealed that green synthesis of zinc nanoparticles by using L. mesenteroides biodegradation 100 nm in size and 10 µg/ml in concentration has potent inhibitory effect against broad range of Salmonella serovars but its salmonicidal effect occurred only at 2000 µg/ml.

Key words: Broilers chicken, Salmonella, Leuconostoc mesenteroides, zinc nanoparticles.