Probiotics/direct fed microbials for Salmonella control in poultry G. Tellez a, ⁎, C. Pixley b , R.E. Wolfenden b , S.L. Layton a,1 , B.M. Hargis a a Department of Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA b Pacific Vet Group-USA, Inc. Fayetteville, AR 72704, USA abstract article info Article history: Received 6 January 2011 Accepted 23 March 2011 Keywords: Probiotic Direct fed microbials Poultry Salmonella Lactobacillus Bacillus Bacterial antimicrobial resistance in both the medical and agricultural fields has become a serious problem worldwide. During the last 15 years, our laboratories have worked toward the identification of probiotic candidates for poultry which can actually displace Salmonella and other enteric pathogens which have colonized the gastrointestinal tract of chickens and turkeys, indicating that selection of therapeutically efficacious probiotic cultures with marked performance benefits in poultry is possible, and that defined cultures can sometimes provide an attractive alternative to conventional antimicrobial therapy. Our studies have been focused on specific pathogen reduction, performance under commercial conditions, and effects on both idiopathic and defined enteritis. We have also confirmed that selected heat-resistant spore-forming Bacillus species can markedly reduce Salmonella and Clostridium when administered in very high numbers, and we have developed a novel and simple technique for obtaining cultured Bacillus spore counts, providing a cost-effective feed-stable inclusion in commercial poultry diets. In order to select even more effective isolates, we are still currently focused on the mechanistic action of the Lactobacillus probiotic previously developed as well as new Bacillus candidates. Current indications are that mechanism of action involves rapid activation of innate host immune responses, providing an exciting possibility for identification of vastly superior and more potent probiotics. In this review, we summarize the safety and efficacy of individual monocultures for prophylactic and/or therapeutic efficacy against Salmonella infections under both laboratory and field conditions as well as the development of a novel, cost-effective, feed-stable direct-fed microbials (DFM) with potential for widespread utilization and improved production, delivery and clinical efficacy for animal use. © 2011 Elsevier Ltd. All rights reserved. 1. Introduction Salmonella enterica serovars continue to be among the most important food borne pathogens worldwide due to the considerable human rates of illness reported, the wide host species that are colonized by members of this remarkable pathogen genus, which serve as vectors and reservoirs for spreading these agents to animal and human populations. Furthermore, the public concern for the appearance of resistant strains to many antibiotics, particularly among zoonotic pathogens such as common Salmonella isolates, is also challenging the poultry industry to find alternative means of control (Boyle, Bishop, Grassl, & Finlay, 2007). For example, in January 2006 Europe implemented a complete ban of growth-promoting antibiotics in animal feed (Anadon, Martinez-Larranaga, & Aranzazu Martinez, 2006). Thus, while attempting to deal with these human food-borne pathogens, poultry producers are simultaneously chal- lenged to improve production in the face of increasing feed costs while using fewer antibiotics due to increased restriction of antimicrobial usage. These internal regulations, as in Europe, were implemented because of export market restrictions and consumer or customer preferences in local markets. For these reasons, continued research on sustainable alternatives to antibiotic growth-promoters for animal production such as: a) probiotics or direct fed microbials (DFM) consisting of live or dead organisms and spores (Patterson & Burkholder, 2003); b) non-traditional chemicals (Ko, Mendoncam, Ismail, & Ahn, 2009); c) bacteriophages (Andreatti Filho et al., 2007; Bielke, Higgins, Donoghue, Donoghue, & Hargis, 2007; Higgins, et al., 2005; J.P. Higgins et al., 2008); and d) organic acids and other plant extracts and essential oils (Aengwanich & Suttajit, 2010; Allen-Hall, Arnason, Cano, & Lafrenie, 2010; Bagchi et al., 2000; Kubena, Byrd, Young, & Corrier, 2001; Over, Hettiarachchy, Johnson, & Davis, 2009; Van Immerseel et al., 2006) is increasingly more important. These potential solutions have emerged in the last decades as some of the tools that could be potentially useful in the near future for pathogen control and poultry performance improvement. Probiosis, although not a new concept, has only recently begun to receive an increasing level of scientific interest. In agriculture, probiotics/DFM used in animal feed are becoming accepted as potential alternatives to antibiotics for use as growth-promoters, and in select cases, for control of specific enteric pathogens (Anadón, Rosa Martínez-Larrañaga, & Aranzazu Martínez, 2006; Boyle et al., Food Research International 45 (2012) 628–633 ⁎ Corresponding author. Fax: + 1 479 575 8490. E-mail address: gtellez@uark.edu (G. Tellez). 1 Current address: Argentina Vetanco S.A. Chile 33 (B1603CMA) Vicente López, Buenos Aires, Argentina. 0963-9969/$ – see front matter © 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.foodres.2011.03.047 Contents lists available at ScienceDirect Food Research International journal homepage: www.elsevier.com/locate/foodres