1a. Objectives (from AD-416)
The objectives of this work include 1) Determine the efficacy of bacteriophage to prevent and treat colibacillosis (Escherichia coli); 2) Determine the efficacy of bacteriophage to prevent and treat turkey coryza (Bordetella avium);and 3) Determine the efficacy of bacteriophage to prevent and treat fowl cholera (Pasteurella multocida).
1b. Approach (from AD-416)
Bacteriophage will be isolated from environmental sources targeted for the bacteria E. coli, Bordetella avium, and Pasteurella multocide. Using our established colibacilosis model we will quantitatively determine the relationship between bacteriophage titers to therapeutic efficacy by treating colibacillosis with different bacteriophage titers, and will conduct in vitro studies to determine if there are any non-specific blood factors that inhibit bacteriophage activity. The efficacy of repeated treatment of bacteriophage will be conducted by administering bacteriophage prior to challenging the birds with the disease agent, and then treating them with an additional bacteriophage administration to determine if prior exposure to high titers of bacteriophage will limit the efficacy of bacteriophage to treat colibacillosis. Bacteriophage from environmental sources will be isolated with effectiveness against Bordetella avium and Pasteurella multocida. Studies will be conducted to determine the efficacy of aerosol administration of bacteriophage to prevent disease by administrating the bacteriophage prior to challenging the birds with Bordetella avium or Pasteurella multocida.
3. Progress Report
We are confident that the experimental model we have developed to study colibacillosis will allow us to pursue two approaches to study the practical administration of bacteriophage to reduce the impact of this disease to the poultry industry. The approaches to be investigated include administration to the incubating egg and to chicks at day of hatch through aerosol administration of bacteriophage. These approaches are practical and could be easily adapted to the current processes used in commercial poultry hatcheries. We experienced more difficulty than anticipated developing an ELISA assay to document the antibody response to bacteriophage in chickens. However, with a lot of trial and error and technical help we completed the development of this assay, allowing us to publish work on the interference of the immune response on bacteriophage efficacy. We terminated our agreement with our CRADA partner, who could not find grant funding to allow them to isolate bacteriophage to a collection of E. coli isolates.
1. Bacteriophage Therapy. We have demonstrated that bacteriophage can be used to prevent colibacillosis in broiler chickens at one week of age. However, to have practical applications in the poultry industry the administration of bacteriophage should be targeted to the newly hatched chick. We developed a model to establish colibacillosis in day-old chicks, which will allow us to study practical methods of administration of bacteriophage. This has the potential to lead to commercial applications of this technology. We have also been able to show and to quantitate that an immune reaction develops directed towards bacteriophage with systemic administration. This immune interaction limits the efficacy of repeated administration of the same bacteriophage, and documents the need for research on ways to prevent immune interference.
5. Significant Activities that Support Special Target Populations
Scientists have participated in activities targeting veterans, minorities and historically underserved small farmers including: 1) serving as Principal Investigator on a SARE grant in cooperation with the ARS Dale Bumpers Small Farms Research Center, Booneville AR; The Kerr Center for Sustainable Agriculture, Poteau, OK; NCAT, Fayetteville, AR; Louisiana State University, Baton Rouge, LA, as well as several small poultry producers in Arkansas; 2) serving as a co-investigator on a Beginning Farmer and Rancher Development Program NIFA grant on a project that provides bilingual English and Spanish whole-farm learning and experiential opportunities for new farmers interested in adopting integrated poultry, small ruminant, and agroforestry production practices, cooperating with the Booneville Unit, the Kerr Center, NCAT, and the University of Arkansas, Fayetteville and Pine Bluff (the 1890 institution for the State of Arkansas); and 3) the Unit partnered with ARS laboratories at Lane, OK; Booneville, AR; and El Reno, OK, to develop and staff an exhibit for the Know Your Farmer, Know Your Food Conference and Gala Dinner in El Reno in July 2010. The Conference was attended by over 200 persons, the majority being small- to mid-sized farmers, institutional food professionals, and extension or outreach specialists.
Huff, W.E., Huff, G.R., Rath, N.C., Donoghue, A.M. 2010. Critical Evaluation of Bacteriophage to Prevent and Treat Colibacillosis in Poultry. Arkansas Academy of Science. 63:93-98.