Source: UNIVERSITY OF DELAWARE submitted to NRP
DEVELOPMENT OF AN INNOVATIVE MASS VACCINE ADMINISTRATION METHOD AT POULTRY HATCHERIES
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
Reporting Frequency
Annual
Accession No.
1015341
Grant No.
2018-67021-28106
Cumulative Award Amt.
$474,306.00
Proposal No.
2017-06387
Multistate No.
(N/A)
Project Start Date
May 15, 2018
Project End Date
May 14, 2023
Grant Year
2018
Program Code
[A1521]- Agricultural Engineering
Recipient Organization
UNIVERSITY OF DELAWARE
(N/A)
NEWARK,DE 19717
Performing Department
Animal and Food Sciences
Non Technical Summary
Vaccination plays a critical role in the health management of poultry production. Numerous economically important infectious diseases are controlled through vaccination. Hatchery spray vaccination of day-old commercial chickens with live vaccines is a common and convenient method. However, the current spray method is not without limitations. Thus, research seeking improvements in hatchery vaccination administration methods is warranted. This research project aims at developing and evaluating an innovative foam-based vaccination technique at poultry hatcheries to improve vaccine efficacy. Foams including vaccines will be produced and spread onto the chicks. The project will focus on accomplishing the following objectives: 1) to investigate and screen the characteristics of foam candidates and the behavior of the chicks when exposed to the foam; 2) to evaluate selected foam candidates on the viability of live vaccines; 3) to develop a foam generation and delivery system for live vaccines under hatchery conditions; and 4) to conduct verification tests using experimental trials in commercial type chickens. The project is expected to develop an understanding of the mechanisms and performance of the foam based mass vaccination administration method for poultry hatcheries and to demonstrate the robustness, simplicity, versatility, and cost-effectiveness of the method. Outcomes of the proposed study will provide research-based information on the application of foam vaccination, improve health and production performance of poultry and keep American agriculture competitive while ending world hunger.The project objectives would address the priority of AFRI foundational program #5: Agriculture Systems and Technology. It fits well into the goals of Engineering Products, and Processes to Improve Agriculturally Relevant Animal and Natural Resource Systems.
Animal Health Component
40%
Research Effort Categories
Basic
30%
Applied
40%
Developmental
30%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
3073299109050%
3073299202050%
Goals / Objectives
The long-term goal of this project is to develop an innovative, effective, and affordable engineering system to improve animal health and production. The project will focus on accomplishing the following objectives:1) To develop a foam generation and delivery system for live vaccines under hatchery conditions;2) To evaluate the effect of foams produced from the prototype systems on virus viability; and3) To verify system performance using experimental trials in commercial type chickens.
Project Methods
Objective 1: To develop full-scale foam generation and delivery systems for live vaccines under hatchery field conditions1.1 Full-scale foam-based mass vaccination administration for hatchery facilitiesBased on the foam selected empirical model developed from the prototype, the two most effective foams from each protein-based and small molecule surfactant-based group will be selected and a full-scale foam vaccination administration system will be designed and developed with considerations of the most influential variables. Three foam generation systems to create foam will be developed: (1) aspirating for high expansion foam, (2) aspirating for medium and low expansion foam, and (3) pressurized aerosol foam. The foam vaccination administration should be similar to the currently used hatchery spray system. In many hatcheries, 100 chicks are placed in a 23.5 L x 18.5 W x 6 H inch plastic tray, which is transported by an automated conveyor system through vaccine coarse spray nozzles. Static cone shape or flat slot scanning type spray systems are used. The typical spray time for one tray varies from 1 to 5 seconds.1.2 Verifying foam characteristics and refining full-scale prototypesThe prototypes will be tested thoroughly with different foam formulations to determine their performances and operation ranges for different parameters. Foams will be produced and tested for their characteristics, such as formability, foam stability, and virus viability. The results will be compared with design parameters and the prototypes will fine-tuned in Objective 2.Objective 2: To evaluate the effect of foams produced from the prototype systems on chick behavior and virus viability2.1 Evaluate effects of foams on chick behaviors and ingestion volumesFoam from the full scale prototype will be further tested with live day-old chicks. The thermal environment, behavior and response of the chicks exposed to the different foams will be measured and quantified. A fluorescent tracing method using fluorescein will used to determine the volume of foam ingested by chicks. First, a calibration curve will be developed to determine the amount of ingested foam by the chicks to the measured reflection signal of the fluorescent. The calibration curve will be generated by gavaging chicks with known volumes of fluorescein water solution. Day-old Cobb 500 chicks from a hatchery will be used and administered a 0.1% fluorescein solution in foam agent at three different volumes (1, 10, 50, 150, 200, 300, 400, and 500 ml) by gavaging. Three chicks will be used per volume. Ten minutes after administering the fluorescein mixtures, the chicks will be euthanized by an approved method and the upper gastrointestinal tract, including esophagus, crop, proventriculus and gizzard, was removed. The removed upper gastrointestinal tract will be placed into an 80-ml Seward filter bag with 1 ml dH2O and double-bagged with a 118-ml black Whirl-Pak bag. The samples will be stomached for 1 min at a speed of 120 rpm and liquid samples in the bags were then placed onto a 96-well polystyrene plate at a 1:2 dilution to determine the optical signal using an absorbance reader (ELx800, Bio-Tek Instruments. Inc., Vermont, USA) at 490 nm excitation level. A standard curve will be created. In each trial, 50 newly hatched chicks will be contained in 50% of the area of a standard plastic chick tray (each tray for 100 chicks) with paper bottom to test the responses of the birds to foams (0.25 to 0.4 g) with different foam temperatures. Fluorescein will be added into the foam agent to create 0.1% concentration. Green food dye will be added to the foam agents and foams will be topically applied to chicks. Foams will be administrated to the chicks trays by the prototypes developed in Objective 1 and compared with coarse spray. A video recording system will be used to capture the behaviors and the response of the chicks exposed to the different treatments over a 10-min period. An ethogram has been developed by our group to analyze the different behaviors using coding software.2.2 Evaluation of the effect of foam candidates on virus viabilityThe prototype will be tested thoroughly with different foam formulations to determine their performances and operation ranges for different parameters. Foams will be produced and tested for their characteristics, such as formability, foam stability, and virus viability. The top two foam candidates selected from Objective 1 for vaccine transport will be evaluated for their effect on the vaccine virus(es). A commercially available IB virus vaccine(s) will be used for the studies as it is routinely applied via spray to baby chicks in the U.S. Favorable foam preparations will be further studied to optimize the prototypes and determine the effect of field prototypes with chicks on virus viability and immune responses.Objective 3: To conduct verification tests using experimental trials in commercial type chickens3.1 Efficacy of vaccines delivered to hatched chicks via novel foam deliveryExperiments will be conducted to demonstrate that immune responses generated in birds after foam vaccination under commercial hatchery conditions. Foam candidates that have favorable properties and do not impact virus viability will be deemed acceptable for in vivo evaluation. Newly hatched chicks will be assigned to treatment groups. The eye-drop control treatment group will be vaccinated according to the manufactures' instructions for ocular instillation. The commercial spray control treatment group will be vaccinated as follows. A standard, 100 capacity chick boxes will be divided in a 60%/40% split. Forty chicks will be placed within the 40% section of the box. One 1,000-dose vaccine vial will be reconstituted in 70mL of distilled water. The chick box will be sprayed with a standard full spray dose of 7 mL in a commercial spray cabinet setup. The foam/vaccine candidates will be applied by the field prototypes developed in Objective 1. Foam application equipment will be cleaned and sanitized between vaccine applications to avoid accidental carryover of vaccine between foam treatments. Chicks will be housed Newark in commercial grow-out conditions and they will be offered feed and water ad libitum. Five days post vaccination (DPV), oro-pharyngeal swabbings will be collected from each bird using a plastic shafted, nylon swab. Each swab will be placed in 2mL of cold, sterile TPB containing 10,000 IU/ml penicillin, 10,000 IU/ml streptomycin, and 250 IU/ml amphotericin B for detection of viral IB vaccine nucleic acid by rRT-PCR (Callison et al., 2006).At 14 DPV, lacrimal excretions and serum will be collected from each chicken and screened by a commercial ELISA kit for the presence of antibodies to the IB vaccine (Gelb et al., 1998). Birds in treatment groups 2 through 8 will be challenged with a homologous live IB virus (104.5EID50/bird) administered via eye-drop. Individual tracheal swabs will be collected 5 days post challenge for virus reisolation attempts in specific pathogen free embryonated chicken eggs (Gelb and Jackwood, 2008). Three, 10-day-old embryos will be inoculated with a given swab sample. A result of one lesion-positive embryo out of three will represent a positive virus isolation (a vaccine failure). Conversely, samples yielding no lesion positive embryos will be considered negative for virus isolation (vaccine successfully induced protection). Tracheas will be evaluated for ciliary activity (Cook et al., 1999). Ciliary activity will be observed with an inverted microscope and scored as; 0, all cilia beating; 1, <100% but >50% of cilia beating; 2, no cilia beating. The average total score for each trachea will be calculated.

Progress 05/15/18 to 05/14/23

Outputs
Target Audience:Poultry company, researchers, vaccine company, and consultants for improving poultry health Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Four undergraduate students were trained through the project by participating in undergraduate research. Two Ph.D. students were trained. These students were involved in conducting experiments, data collection and analysis, visiting commercial farm, evaluating animals, and reprenting results. How have the results been disseminated to communities of interest?The results of the project were disseminated to avian vaccine and equipment companies through marketing news announcement. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? The long-term goal of this project is to develop an innovative, effective, and affordable engineering system to improve animal health and production. The project will focus on accomplishing the following objectives: 1) To develop a foam generation and delivery system for live vaccines under hatchery conditions; 2) To evaluate the effect of foams produced from the prototype systems on virus viability; and3) To verify system performance using experimental trials in commercial type chickens.

Publications


    Progress 05/15/21 to 05/14/22

    Outputs
    Target Audience:Poultry company, researchers, vaccine company, and consultants for improving poultry health Changes/Problems:There were many delays in receiving neccessary supplies for experiments due to the supply issues and avian influenza outbreak in our region. These delays caused major setback and we had to request for a one-year no-cost extension. What opportunities for training and professional development has the project provided?Five undergraduate students were trained through the project by participating in undergraduate research. One Ph.D. student and one Master student were trained. The students presented their finding in different conferences including University of Delaware College of Ag Unique Strenghth Symposium and Poultry Science Association Annual meeting. How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?The final part of the project will be to evaluate the foam performance under different environmental conditions, develop new foam agents and mprove the stability of the foams.

    Impacts
    What was accomplished under these goals? A full-scale foam vaccination system was developed and finalized. The system consists of five foam nozzles, compressed air tank, air pressure regulator, two liquid pumps, a mixing chamber, and a liquid manifold.The development nozzle was designed using CAD and had its major components machined out of aluminum. Major components included the nozzle body and tip. A steel bung was placed into the top portion of the nozzle to allow for a secure seal. An aluminum bung was also inserted into the bottom opening of the nozzle that allowed for the aluminum tip to be screwed into the nozzle. The internal filter capsule pieces were 3D printed and 600-micron and 400-micron nylon screens were attached to the lower capsule with super glue. Two nylon thread adaptors for ¼" ID tubing were used for air and liquid input. Different foam agents were evaluated with the full-scale system.The results of the testsshow that the nozzle is capable of producing stable edible foams. The expansion rate, bubble size, and liquid drainage are within the parameters (expansion rate: 20-50, bubble size: 2mm-8mm, liquid drainage:<95% by 10 minutes). The deterioration rate is not within parameters (deterioration rate: 50% at five minutes. The quality of the foams is consistent with theaverage expansion rate ranging from 25.69 - 33.58, the average bubble size ranging from 3.05 - 3.52mm. the average liquid drainage at 10 minutes ranging from 59% - 91%, and an average deterioration rate at 5 minutes ranging from 97.3% - 98.2%. The results show that this foam was able to successfully resist the issues that are seen with spray vaccination. The full-scale foam vaccination system was evaluated to determine the feasibility of using the foam system as a vaccinationmethod for chicks in the hatchery. The novel foam vaccination system was compared to spray and eyedrop vaccination methods.The results from this study suggest that the foam vaccination system is able to successfully inoculate and protect chicks against IBV challenge by utilizing an edible foam as the vaccine vehicle in either one or two-pass application scenarios. The uniformity of application is reflected by the titers seen for the RT-PCR. The 2-pass application had an average titer of 14942 ±1969 for RT-PCR while the 1-pass application had an average titer of 891 ± 2306, both of which are not significantly different from the spray vaccination titer of 11199 ± 3607.The ELISA further confirmed this with 1-pass application attaining an average ab titer of 1730 ± 361 and the 2-pass vaccination attaining an average ab titer of 2318 ± 406 compared to spray vaccinations average titer of 936 ± 200. The protection provided by the foam is seen in the tracheal lesion scores with 1-pass application having an average score of 1.97 ± 0.19 and 2-pass application having an average lesion score of 1.16 ± 0.22. These scores were not different from either the challenged eyedrop groups score (1.29 ± 0.15) or the spray groups score (1.94 ± 0.23). The induction of neutralizing immunity is also seen in both 1-pass and 2-pass applications with 1-pass application having only 5 out of 31 samples that had active viral infection and 2-pass application having only 1 out of 21 samples with an active viral infection. These were both better than the spray vaccination which had 8 out of 33 samples that were infected. Taking these factors into consideration, the use of foam as a vaccine vehicle should be further explored to better protect the flocks and interests of the poultry industry.

    Publications

    • Type: Theses/Dissertations Status: Published Year Published: 2022 Citation: Elliott, Kenneth C. 2022. Development and verification of a novel foam vaccination system for chicks. University of Delaware
    • Type: Conference Papers and Presentations Status: Published Year Published: 2022 Citation: Elliott, K. and Li, H. 2022. Validation of a Novel Foam Vaccination System for Chicks in the Hatchery. Poultry Science Association Annual Meeting, San Antonio, Texas, July 11-14, 2022.
    • Type: Conference Papers and Presentations Status: Published Year Published: 2022 Citation: Li, H. 2022. Development of a new foam vaccination method for poultry in the hatchery. ASABE Annual International Meeting, Houston, Texas, July 18-20, 2022.


    Progress 05/15/20 to 05/14/21

    Outputs
    Target Audience:Poultry company, researchers, vaccine company, and consultants for improving poultry health 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? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?A full-scale system for field conditions will be completed and further tested with live day-old chicks. The thermal environment, behavior and response of the chicks exposed to the different foams will be measured and quantified. A fluorescent tracing method using fluorescein will used to determine the volume of foam ingested by chicks. The full-scale system will be evaluated for its effect on the vaccine virus(es). A commercially available IB virus vaccine(s) will be used for the studies as it is routinely applied via spray to baby chicks in the U.S. Experiments will be conducted to demonstrate that immune responses generated in birds after foam vaccination under commercial hatchery conditions.

    Impacts
    What was accomplished under these goals? The project has successfully created a working concept foaming prototype that can produce uniform egg white foam. A foam nozzle was designed based on the aspiration of foam agents by mixing an air stream with a liquid flow in a closed chamber with single discharge orifice. This design was chosen due to its relative simplicity and the fact that the foam would have the least contact time with the nozzle which is important as foaming agents can dry quickly and leave a sticky residue. This would cause build up and thus effect the uniformity of the foam or operation of the machine. The foam agent that was selected was the 75% to 25% egg white to deionized water mix that was used in the preliminary work done for the project. Egg white was chosen as our foaming agent as it has well known foaming capabilities in addition to the preliminary work providing the insight that itwas a viable candidate. The nozzle and foam have been tested thorough as outlined in the approaches. The expansion rates were found to be varied, ranging 10 to 30 times based on proportion of air to liquid, and by flow rate of the air, ranging from 1:50 to 1:100. Liquid drainage varied from 55% to 85% , although all proportions and flowrate combinations had 10-minute drainage times greater than 70%. The bubble size was found to be relatively uniform which was expected as the exit filter is the main control for the final bubble size. After four nozzle setting candidates were selected, tests were then conducted to determine if there would be any negative effects of the foam making process on the vaccine that was being delivered in the foam. These tests are outlined in approach 3.2.1. The test was initially going to be done twice, with the test having the foam sit for 1 hour and the other test having the foam sit for 2 hours. The first test proved unsuccessful as too many of the eggs died before being able to attribute their deaths to IBV infection. The second test produced good data that showed that while the actual production of the foam wasn't harmful to the vaccine, there appeared to be a loss of efficacy in the samples that utilized egg white as the vehicle. Additionally, no endpoint titers were reached for the controls. A further test was conducted to determine if the loss of efficacy was due to the pH of the egg white. The data was contradictory to the first experiment, as the control, pH8 solution, pH9 solution, and egg white solutions all had a similar titer of vaccine, indicating that our initial conclusion of loss of efficacy may have been unfounded. Considering these results, we were moving forward with testing and began the ingestion and bursal viability trials.

    Publications


      Progress 05/15/19 to 05/14/20

      Outputs
      Target Audience: Poultry company, researchers, vaccine company, and consultants for improving poultry health Changes/Problems:The project was greatly impacted by Covid-19 pandemic. The project had been on hold since Mid-March, 2019 and was reactivated in July 2019. However, our lab is currently running 30% of its capacity and the project is currently about 6 months behind our plan. One of Co-PDs, Dr. Eric Benson, suddenly passed away in April 2019. We redistributed the workloads among the remaining team members to fulfill Dr. Benson's role. What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? We will further improve foam vaccination systems and evaluate the effect of foams produced from the foam vaccination systems on virus viability and verify system performance using experimental trials in commercial type chickens.

      Impacts
      What was accomplished under these goals? The team has been focusing on further optimize an air-liquid aspiration foam generation system and characterize foam properties. Experiments were conducted to evaluate selected foam candidates on the viability of live vaccines. The preliminary results showed that the tests withthe egg whites based foam had an endpoint around10^-4 whereas the tests utilizing water had an endpoint >10^-5 similarto the positive control (water+ vaccine). There was most likely no mechanical damage being caused by the foam generation system which is positive, but some other source is causing a decrease in titer. Our current theory is that either 1) the virus was interacting with some proteinin the eggwhite that is preventingefficacy or 2) the pH of the eggwhite is causing the vaccine to drop in efficacy. We are planning to conduct some more testing looking at the effect of the pH and the possibility of the vaccine interacting with some of the egg white proteins.

      Publications


        Progress 05/15/18 to 05/14/19

        Outputs
        Target Audience: Poultry company, researchers, vaccine company, and consultants for improving poultry health 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?A poster presentation was presented in the College of Agriculture and Natural ResourcesUnique Strength forth annual Research Symposium at University of Delaware. What do you plan to do during the next reporting period to accomplish the goals?We will evaluate the effect of foams produced from the prototype systems on virus viability andverify system performance using experimental trials in commercial type chickens.

        Impacts
        What was accomplished under these goals? The team has been focusing on foam generation system development from May 2018 to May 2019. An air-liquid foaming nozzle prototype has been designed and fabricated in the lab. A sugar-protein based new foaming agent was formulated and tested with the newly-designed nozzle. The foaming properties of the sugar-protein based foams were tested and compared with egg white. The results showed that the air-liquid nozzle system was capable of consistently producing foam with desired qualities and ready for more vigorous testing and polished design.

        Publications

        • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Elliott, K.C., Li, H. 2019. Development of a Novel Foam-based Vaccination System for Chicks in the Hatchery. University of Delaware, College of Agriculture and Natural Resources, Unique Strength forth annual Research Symposium. Newark, Delaware. May 3, 2019.