title: Temporal distribution of encapsulated bacteriophages during passage through the chick gastrointestinal tract.
abstract: Encapsulation of bacteriophages ("phage") protects phage against environmental deactivation and provides a product that is easy to handle for storage and application with animal feed as an antibiotic alternative. The objective of this study was to evaluate an orally administered, encapsulated phage for efficient phage release in the gastrointestinal tract (GIT) of young chicks receiving feed. An optimized formulation that consisted of 0.8% low molecular weight (MW) alginate, 2% ultra-low molecular weight alginate and 3% whey protein completely released the encapsulated phage within 60 min under simulated intestinal conditions. This product was given to broiler chicks to determine passage time and distribution of the viable phage within the GIT. Following a single oral dose of 109plaque-forming unit (PFU)/chick, the major portion (peak concentration) of the encapsulated phage passed through the chick's GIT and was detected in the feces within 4 h, with low levels being continuously excreted for up to 24 h. In comparison, the passage of free phage through the GIT occurred faster as indicated by a peak concentration in feces after 1.5 h. In assessing the temporal phage distribution, both encapsulated and free phage treatments showed no apparent difference, both having low levels of 102to 106PFU/g of contents along the entire GIT after 1, 2 and 4 h. These low concentrations recovered in vivo led us to examine various exposure conditions (with feed, fecal material, and buffer solutions) that were suspected to have affected phage viability/infectivity during oral delivery, sample recovery, and enumeration by plaque assay. Results showed that the exposure conditions examined did not significantly reduce phage viability and could not account for the observed low phage levels following oral administration in chicks that are on feed. In conclusion, an oral encapsulated phage dose can take more than 4 h to completely move through the GIT of young chicks. Thus, repeated or higher doses may be necessary to attain higher phage concentrations in the GIT.
authors: Guelph Research and Development Centre, Agriculture and Agri-Food Canada, 93 Stone Road West, Guelph, Ontario N1G 5C9, Canada.|Graduate Department of Pharmaceutical Sciences, University of Toronto, 144 College Street West, Toronto, Ontario M5S 3M2, Canada.
authors: Yin-Hing
authors: YH
authors: Ma
authors: Guelph Research and Development Centre, Agriculture and Agri-Food Canada, 93 Stone Road West, Guelph, Ontario N1G 5C9, Canada.|Department of Food Science, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors: Golam S
authors: GS
authors: Islam
authors: Guelph Research and Development Centre, Agriculture and Agri-Food Canada, 93 Stone Road West, Guelph, Ontario N1G 5C9, Canada.
authors: Ying
authors: Y
authors: Wu
authors: Guelph Research and Development Centre, Agriculture and Agri-Food Canada, 93 Stone Road West, Guelph, Ontario N1G 5C9, Canada.
authors: Parviz M
authors: PM
authors: Sabour
authors: Guelph Research and Development Centre, Agriculture and Agri-Food Canada, 93 Stone Road West, Guelph, Ontario N1G 5C9, Canada.
authors: James R
authors: JR
authors: Chambers
authors: Guelph Research and Development Centre, Agriculture and Agri-Food Canada, 93 Stone Road West, Guelph, Ontario N1G 5C9, Canada qi.wang@agr.gc.ca.
authors: Qi
authors: Q
authors: Wang
authors: Graduate Department of Pharmaceutical Sciences, University of Toronto, 144 College Street West, Toronto, Ontario M5S 3M2, Canada.
authors: Shirley X Y
authors: SX
authors: Wu
authors: Department of Food Science, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors: Mansel W
authors: MW
authors: Griffiths
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001435:Bacteriophages / Q000502:physiology*; D002214:Capsules / Q000008:administration & dosage; D002645:Chickens / Q000382:microbiology / Q000821:virology*; D005243:Feces / Q000821:virology; D041981:Gastrointestinal Tract / Q000821:virology*; D011201:Poultry Diseases / Q000382:microbiology / Q000517:prevention & control; D012481:Salmonella Infections, Animal / Q000517:prevention & control; D013997:Time Factors
chemical_list: D002214:Capsules
keywords: Bacteriophage; broiler chicks; oral phage therapy; salmonella Typhimurium DT104