An in vitro assay to evaluate competitive exclusion products for poultry.

An in vitro assay was developed to measure the ability of competitive exclusion (CE) bacteria to protect Caco-2 and CRL-2117 epithelial cells from invasion by Salmonella Typhimurium. The proposed assay is needed to expedite the development of defined-flora CE products. The average significantly protective concentration of the commercial poultry-specific CE product Preempt was 4.05 log CFU/6.41 log human Caco-2 cells and 3.71 log CFU/6.89 log CFU chicken CRL-2117 cells, Enterococcus faecalis isolated from Preempt protected CRL-2117 cells, Escherichia coli isolates protected Caco-2 cells, Lactococcus lactis and Bacteroides distasonis isolates protected both cell lines, and three species of Lactobacillus isolates failed to protect either cell line. A defined mixture of 29 strains of bacteria similar to the constituents of Preempt protected both cell lines from Salmonella invasion at a concentration of 7.83 log CFU. The constituents of the defined CE culture were separated into mixtures of obligate (8.42 log CFU) and facultative (8.49 log CFU) anaerobes, which both protected the cell lines, suggesting that both types of bacteria were equally protective. Although not a substitute for in vivo testing, the in vitro CE assay is a rapid technique for the evaluation of bacterial mixtures for potential CE products.

[1]  T. Mattila-Sandholm,et al.  Probiotic bacteria: safety, functional and technological properties. , 2000, Journal of biotechnology.

[2]  M. Goodwin,et al.  Comparison of a Lyophilized Chicken-Origin Competitive Exclusion Culture, a Lyophilized Probiotic, and Fresh Turkey Cecal Material Against Salmonella Colonization , 2000 .

[3]  W. Witte.  Ecological impact of antibiotic use in animals on different complex microflora: environment. , 2000, International journal of antimicrobial agents.

[4]  J. Deloach,et al.  Drinking Water Delivery of a Defined Competitive Exclusion Culture (Preempt) in 1-Day-Old Broiler Chicks , 2000 .

[5]  G. Mead.  Prospects for 'competitive exclusion' treatment to control salmonellas and other foodborne pathogens in poultry. , 2000, Veterinary journal.

[6]  G. Oliver,et al.  Some probiotic properties of chicken lactobacilli. , 1999, Canadian journal of microbiology.

[7]  K. Darwin,et al.  Molecular Basis of the Interaction ofSalmonella with the Intestinal Mucosa , 1999, Clinical Microbiology Reviews.

[8]  S. Salminen,et al.  Adhesion of some probiotic and dairy Lactobacillus strains to Caco-2 cell cultures. , 1998, International journal of food microbiology.

[9]  L. Palmu,et al.  The use of competitive exclusion in broilers to reduce the level of Salmonella contamination on the farm and at the processing plant. , 1997, Poultry science.

[10]  P. Aye,et al.  Evaluation of an avian-specific probiotic to reduce the colonization and shedding of Campylobacter jejuni in broilers. , 1997, Avian diseases.

[11]  G. Salvat,et al.  Bacteriological monitoring of Salmonella enteritidis carrier birds after decontamination using enrofloxacin, competitive exclusion and movement of birds , 1997, Veterinary Record.

[12]  S. Altekruse,et al.  Therapeutic antibiotics in animal feeds and antibiotic resistance. , 1997, Revue scientifique et technique.

[13]  G. Tannock.  Probiotic properties of lactic-acid bacteria: plenty of scope for fundamental R & D. , 1997, Trends in biotechnology.

[14]  C. Hofacre,et al.  Application of normal avian gut flora by prolonged aerosolization onto turkey hatching eggs naturally exposed to Salmonella. , 1997, Avian diseases.

[15]  F. Aarestrup,et al.  Isolation of vancomycin resistant Enterococcus faecium from food. , 1997, International journal of food microbiology.

[16]  A. Hoszowski,et al.  Prevention of Salmonella typhimurium caecal colonisation by different preparations for competitive exclusion. , 1997, Comparative immunology, microbiology and infectious diseases.

[17]  S. Craven,et al.  Bacterial Isolates from the Chicken Gizzard and Ceca with In Vitro Inhibitory Activity against Salmonella typhimurium. , 1997, Journal of food protection.

[18]  A. Servin,et al.  Antagonistic activity exerted in vitro and in vivo by Lactobacillus casei (strain GG) against Salmonella typhimurium C5 infection , 1997, Applied and environmental microbiology.

[19]  S. Ricke,et al.  Cecal Propionic Acid as a Biological Indicator of the Early Establishment of a Microbial Ecosystem Inhibitory toSalmonellain Chicks , 1996 .

[20]  D. Nisbet,et al.  Control of Salmonella typhimurium colonization in broiler chicks with a continuous-flow characterized mixed culture of cecal bacteria. , 1995, Poultry science.

[21]  S. Ricke,et al.  Inoculation of Broiler Chicks with a Continuous-Flow Derived Bacterial Culture Facilitates Early Cecal Bacterial Colonization and Increases Resistance to Salmonella typhimurium. , 1994, Journal of food protection.

[22]  J. D'aoust,et al.  Undefined and Defined Bacterial Preparations for the Competitive Exclusion of Salmonella in Poultry - A Review. , 1993, Journal of food protection.

[23]  M. Wishart,et al.  Effects of okadaic acid indicate a role for dephosphorylation in pancreatic stimulus-secretion coupling. , 1992, The American journal of physiology.

[24]  E. Nurmi,et al.  New Aspects of Salmonella Infection in Broiler Production , 1973, Nature.