Screening of Plants for Inhibitory Activity Against Pathogenic Microorganisms from the Gut of Livestock

Abstract

One of the major hazards facing the livestock industries in food safety is commensal gut microorganisms (e.g. Escherichia coli, Listeria monocytogenes, Yersinia enterocolotica, Campylobacter spp. and Salmonella spp.), which contaminate animal products and cause illness in humans. Traditionally, pathogenic gut microorganisms have been controlled by antibiotic growth promoters [8]. Use of such supplements in livestock is being phased out because of the emergence of antibiotic-resistant human-pathogens [4]. The use of growth promoters as feed supplements in livestock was banned by the European Union at the start of 2006 and similar bans are under review in Australia [16]. A number of approaches, such as vaccination, probiotics, chemical inhibitors and dietary manipulation are being considered for reducing these organisms in livestock. One possible control strategy is the use of natural antimicrobial plant compounds as an alternative to antibiotic growth promoters. These plants could then be incorporated into animal feeding systems provided there were no adverse affects on the animal and the products from those animals [6, 3].