Progress 10/01/09 to 09/30/14
Outputs
Target Audience: The goal of research in this project was to address high priority, industry-identified issues to increase production efficiencies and profitability of aquaculture in the southeastern United States. The target audience for new information and technologies developed in this project are American catfish farmers, research scientist and fish health professionals. Farmers using the vaccination practices developed from this project will improve production efficiencies by decreasing losses associated with bacterial infections. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?
Nothing Reported
How have the results been disseminated to communities of interest? Knowledge developed in this project is passed to user groups through a formal network of extension program specialist in the state who use workshops, conferences, seminars, and newsletters to disseminate the information. Investigators also deliver this knowledge to other scientist and students of aquaculture through professional meetings, peer-reviewed scientific publications and lectures. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
This project lead to the development and validation of procedures for commercial scale vaccine production and a mechanized system for orally delivering live attenuated vaccines to fish. Vaccine serials were produced in 50 L floor model fermentors, concentrated and frozen for stability. Each vaccine serial was validated in laboratory tests and all serials were shown safe (negligible or no mortality at 10X the target dose) and offered an exceptional level of protection againstE. ictaluriinfection with RPS values in excess of 92%. The oral vaccination platform developed from this project was validate in experimental and commercial scale field trials. In repeated pond trials, vaccination resulted in approximately two-fold improvements in survival and feed conversion ratios and a three-fold increase in projected net sales. Based on field trial data, implementation of this oral vaccination platform will greatly reduce disease related costs and substantially increase the net profitability of catfish farming and help to insure the economic viability of the U.S. catfish industry.
Publications
- Type:
Journal Articles
Status:
Submitted
Year Published:
2014
Citation:
Wise, D. J., T. E. Greenway, T. S. Byars, M. J. Griffin, and L. H. Khoo. (accepted) Oral vaccination of channel catfish against enteric septicemia of catfish (ESC) using a live attenuated Edwardsiella ictaluri vaccine. Journal of Aquatic Animal Health
- Type:
Other
Status:
Published
Year Published:
2013
Citation:
Wise, D.J., T. Greenway, and T.S. Byars. 2013. Oral vaccination of fish with live attenuated Edwardsiella ictaluri vaccines. (US Patent Number 2,001,155,998)
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Progress 01/01/13 to 09/30/13
Outputs
Target Audience: The goal of research in this project is to address high priority, industry-identified issues to increase production efficiencies and profitability of aquaculture in the southeastern United States. The target audience for new information and technologies developed in this projectwasthe U.S. catfish farmer, research scientists, extension specialists, and fish health professionals. Ultimately, American consumers will be the major beneficiaries through the production of an inexpensive, safe, domestically produced seafood product that will help offset the large U.S. trade deficit in seafood commodities. Knowledge developed in this project was passed to user groups through a formal network of extension program specialists utilizing workshops, seminars, advisory groups, and demonstration projects involving farmer user-groups. Investigators also delivered the findings of this project to other scientist and students of aquaculture through professional meetings. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? A licensing plan for the vaccine has not been formalized but Mississippi State University administration and scientists at the National Warmwater Aquaculture Center are working closely with industry advisory groups to develop a launch plan. A component of this process isthehands-oninvolvementof catfish producers, feed-mills and service industries that help support the catfish industry. These training sessions include workshops, seminars, and demonstration projects where farmers are involved in the actualvaccination process. Industry feedbackis thenused to address potential logistical flaws in the vaccination process and is used to define protocols and procedures for on-farm application. A yearly progress report is presented to stake holders at annual industry meetings and extension workshops. How have the results been disseminated to communities of interest? Results of this body of work have been disseminated to industry advisory groups, catfish farmers, other scientist and extension specialists, service industries that support the catfish industry. Data has been presented at commodity organization meetings, extension workshops and scientific meetings. Demonstration projects with hands-on farmer involvement were also used to as an educational tool toenhance stakeholder understanding in the vaccination process. What do you plan to do during the next reporting period to accomplish the goals? Production data from the field vaccination trials will be tabulated and analyzed to evaluate the effectiveness of vaccination. Comparison of feed fed, growth, biomass, feed conversion ratios, survival and estimated gross sales between vaccinated and non-vaccinated treatments will be used to assess vaccine efficacy. Informationgenerated from this project will be used to obtain approval to conduct vaccination trials on commercial farms. Commercial vaccination trials will be conducted on a minimum of 3 farms to generate safety and efficacy data as part of the licensing process. Information will be presented to stakeholders at extension workshops and at meetings held by commodity organizations.
Impacts
What was accomplished under these goals?
Enteric septicemia of catfish, is a costly bacterial disease affecting channel catfish and is estimated to cost the industry 60 million dollars annually in direct and indirect losses. Historically, control of ESC has been accomplished by restricting feed prior to the onset of disease and the use of medicated feeds, both of which have drawbacks. Feed restriction is very effective in slowing the spread of disease but results in a tremendous loss in production due to lost feed days. It is estimated that feed restriction reduces the opportunity to feed fish within a given production season by 25-30%. Conversely, the use of medicated feed allows for growth during a disease outbreak, butit's effectiveness islimited due to poor drug delivery resulting from disease induced anorexia. Medicated feeds are also expensive and their overuse leads to the development of resistance rendering the antibiotics ineffective. A more effective and cost effective method of disease control is through vaccination. Our research endeavors has led to the development of a new live attenuated E. ictaluri vaccine and delivery system allowing for the oral vaccination of fish. The vaccine is mixed with feed at the point of delivery to ensure optimal viability of the vaccine cells. The new method of oral delivery has been shown safe and effective in laboratory tests and experimental field trials. In repeated experimental pond trials vaccination resulted in two-fold improvements in survival and feed conversion ratios and a three-fold increase in projected net sales. While research has validated the effectiveness of the vaccine and vaccination strategy, a commercialized form of the vaccine has not been developed. Commercialization of the vaccine is dependent on a number of factors including; development of fermentation protocols allowing for mass production of the vaccine, development of vaccine stabilization strategies to prevent vaccine inactivation during storage and transport, and fulfillment of regulatory research (i.e. absence of reversion or increase in virulence) required for the registration or licensure of live vaccines. The objectives of this project will address these critical components of the commercialization process allowing for the petitioning of USDA/APHIS for approval to conduct commercial field trials. Commercial scale fermentation trials were developed based on protocols for the experimental production and storage of a newly developed live attenuated ESC vaccine developed through our research efforts. The fermentation inoculum was produced from a series of validated steps originating from a master seed line. Fermentation parameters (pH, gas mixture, inoculum volume) were developed in a systematic approach using 10L and 50L floor model fermentors. The fermented culture was processed and frozen in 50 ml aliquots. The culture was processed to produced a commercialized form of the vaccine and procedures validated by determining cell viability, immunogenicity, and self-life. No changes in cell viability were observed before and after processing and in mock feed distribution trials. Delivery of the processed vaccine/feed admix to catfish fingerlings resulted in high levels of protection against E. ictaluri infection in laboratory tests. The processed vaccine was used in commercial scale field trials and delivered to fish using a mechanized vaccine delivery system, developed from a previous project within this multi-state project. Immunizing doses were present in the feed/admix at the point of delivery validating the use of the processed vaccine in the vaccine delivery system. The field vaccination trial is on-going but feed recordsshow increased feed consumption in vaccinated fish, a preliminary indicator of vaccine efficacy. Vaccinated and non-vaccinated ponds of fish were harvested outside the reporting period of this project and will be reported in the next reporting period. Based on data from previous field trials, implementation of this oral vaccination platform will greatly reduce disease related costs and substantially increase the net profitability of catfish farming and help to insure the economic viability of the U.S. catfish industry.
Publications
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Progress 06/01/12 to 12/31/12
Outputs
OUTPUTS: Enteric septicemia of catfish (ESC), one of the most costly diseases of the channel catfish industry, is caused by a gram negative enteric bacterium identified as Edwardsiella ictaluri. The exact economic impact of this disease is unknown but is estimated to cost the industry $30-$60 million annually. To improve the efficacy of vaccination, we developed a live attenuated strain of E. ictaluri for oral delivery. The vaccine/feed admix was shown to offer a high level of protection against E. ictaluri infection in laboratory trials. Experimental pond trials culminated in dramatic improvements in production efficiencies. While the developed vaccine virtually eliminated mortality associated with ESC, a standardized method for uniformly mixing and delivering the vaccine/feed admix on a larger scale must be developed for commercial application. To circumvent this limitation a mechanized delivery vaccine delivery system was developed by the Department of Agricultural and Biological Engineering, Mississippi State University. The system was validated in mock vaccination trials and in 1.0 acre experimental field trials. Information obtained from these trials has been presented at scientific professional meetings and educational workshops. Commercial field trials are scheduled for the 2013 production season. PARTICIPANTS: Wise DJ. Microbiologist. Principle Investigator, Mississippi State University. Role: Fish health research, experimental design, analysis Greenway T. Immunologist. Co-Principle Investigator, Mississippi State University. Role: Fish health research, experimental design, analysis Griffin M. Molecular biologist. Mississippi State University-College of Veterinary Medicine Role: PCR design, genetic characterization Khoo L. Pathologist. Mississippi State University-College of Veterinary Medicine Role: Fish Diagnostics, Pathology Walker C. Research Technician, Mississippi State University Role: Pond and Facility Manager, sample collection Walker J. Research Associate, Mississippi State University Role: Immunological assays, sample collection and analysis Morris R. Research Technician, Mississippi State University Role: Fish husbandry, Chesser D. Engineer, Mississippi State University Role: Design and Construction Davis J. Engineer, Mississippi State University Role: Design and Construction Byars T. Research Associate, Mississippi State University Role: Research supervisor, Microbial cultures, sample collection and analysis TARGET AUDIENCES: The goal of research in this project is to address high priority, industry-identified issues to increase production efficiencies and profitability of aquaculture in the southeastern United States. The target audience for new information and technologies developed in this project are American catfish farmers. Farmers using the vaccination practices developed from this project will improve production efficiencies by decreasing losses associated with bacterial infections. Knowledge developed in this project is passed to user groups through a formal network of extension program specialist in the state who use workshops, conferences, seminars, and newsletters to disseminate the information. Investigators also deliver this knowledge to other scientist and students of aquaculture through professional meetings, peer-reviewed scientific publications and lectures. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
During the mock vaccination trial, the minimum target dose of viable cells/g feed was delivered at all sampling intervals and did not exceed the maximum allowable limit. Data demonstrated uniform delivery of a consistent target dose. The automated delivery system was validated in 1.0 acre experimental pond trials to established proof of concept. Channel catfish fry were stocked into 16 one acre ponds between May-June at a rate of 120,000 fry/acre and managed according to standard industry practices. When feeding rates approach 50lb/acre/day, fish were vaccinated with the attenuated vaccine using the automated delivery system. Feed fed, growth, biomass, feed conversion ratios, survival, and estimated gross sales were used to assess production efficiencies and vaccine efficacy. Vaccination was shown to dramatically increase the amount of feed fed, growth, survival, feed efficiency and projected economic returns. Vaccination increased overall survival by 81.2%, resulting in a 86% increase in harvested biomass. Compared to controls, vaccinated fish consumed 38% more feed with a 32.2% reduction in the feed conversion ratio (2.11 vs 3.11). Since feed is the largest variable cost in production, this reduction in FCR represents a dramatic increase in production efficiency. For example, given a feed cost of $600/ton, the cost of feed to produce 1 lb of vaccinated fish was $0.63 compared to a feed cost of $0.93 to produce the same weight of non-vaccinated fish. Increased production resulting from vaccination increased gross sales from $2,601 to $4,823 on a per acre basis.
Publications
- Wise, D., T. Greenway, G. Griffin, L. Khoo, and T. Byars. 2012. In‐pond Vaccination of Channel Catfish Using an Orally Delivered Experimental ESC Vaccine. In proceedings of the Catfish Farmers of America Annual Convention of Research Symposium. Savannah GA. February 16-18, 2012.
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