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IDEXX APV Ab Test Test With Confidence™ Effective tool for monitoring avian pneumovirus in chicken and turkey flocks The IDEXX APV Ab Test is an indirect ELISA for the detection of APV antibodies in chicken and turkey serum. This test has been developed as a flock-screening tool to aid in the diagnosis of APV. •Detects A, B and C avian pneumovirus types •Detects vaccine immune response 16 days after vaccination •Chicken and turkey serum samples •98% specificity in SPF populations •Indirect—quantitative ELISA DRAFT GD1R 9.9.10 GD2R 9-13-10 RF1R FNP FNSO Avian pneumoviruses (APV) can cause damage to the upper respiratory tract (trachea), such as, lack of cilia movement and/or cilia loss—damage that may lead to respiratory clinical signs such as coughing, sneezing, swollen head and more complicated respiratory problems. This stress on the cilia and upper respiratory tract can facilitate the multiplication of E. coli and other bacterial infections such as Mycoplasmas, Bordetella sp, etc. that lead to a respiratory syndrome called swollen head syndrome (SHS).1 APV plays a role in the multiplication of infectious bronchitis virus (IBV) in the upper respiratory tract. APV can also affect the reproductive tract, impacting egg formation in turkey breeders, broiler breeders and egg-type chickens, resulting in an increase in the percentage of egg abnormalities and a drop in egg production.2,3 The most prevalent types of APV are A and B, but type C is present in some poultry states in the United States.3 For this reason, it is important for monitoring purposes to have a diagnostic test that is able to detect any of the potential APV strains in the commercial chicken and turkey industries. The IDEXX APV Ab Test is a quantitative test for the detection of A, B and/or C APV-specific types in specific pathogen-free (SPF), as well as commercial, chicken and turkey flocks that could be exposed to field or vaccine viruses. This test and xChek* software can help to screen SPF populations or monitor flocks that have been vaccinated with live or inactivated vaccine against A, B and/or C APV types. IDEXX recommends building a baseline for each company. References: 1 Jones RC. Viral respiratory diseases (infectious bronchitis, infectious laringotracheitis and avian pneumovirus). Proceedings from: XIII Congress of the World Veterinary Poultry Association; Denver, Co; July 20–23, 2003:39–41. 2 Cook JK. Avian pneumovirus infections of turkeys and chickens. Vet J. 2000;160(2):118–125. 3 Cook JK, et al. Infectious bronchitis virus vaccine interferes with the replication of avian pneumovirus vaccine in domestic fowl. Avian Pathology. 2001;30:233–242. 4 Goyal SM. Seroprevalence of avian pneumovirus in Minnesota turkeys. Avian Dis. 2003;47(3):700–6. IDEXX APV Ab Test Graph 1 IDEXX APV Ab Test German SPF chicken population n=612 Specificity = 98.4% MEAN S/P = 0.058 STD = 0.047 STDs from cutoff = 3.0 160 This study consisted of 18 chickens. The first group was vaccinated with inactivated type A vaccine, another two groups with type B vaccines and the fourth was a nonvaccinated control group. Serum samples were taken from the day of vaccination up to 43 days after vaccination. The percentages of seroconversion and mean titers for each group are shown in graphs 5 and 6. Cutoff = 0.2 140 120 Frequency The IDEXX APV Ab Test (graph 1) performed better than the gold-standard competitive, or blocking, ELISA (graph 2), with 98.4% specificity vs. 96.9%, respectively. The cutoff in graph 1 for the IDEXX APV Ab Test is 0.2, whereas, the arrows in graph 2 indicate the suspect zone for the blocking ELISA test . Sensitivity: Chickens with type A and B vaccines 100 80 60 40 20 4 46 0. 0. 0. 34 28 0. 0. 22 0.1 6 0.1 2 04 0. 8 .0 .0 -0 .14 -0 -0 -0 .2 0 S/P Vaccine B1 Vaccine B Control 90% 80% 70% 60% 50% 40% 30% 20% Suspect Zone 50 40 A decline in antibodies was seen 43 days after vaccine application in all of the groups. between 30% to 40% 30 0% 0 16 23 30 35 43 Days post-vaccination Graph 6: Mean titers with the IDEXX APV Ab Test—in chickens vaccinated with inactivated product containing A or B antigen Vaccine A Vaccine B1 Vaccine B Control 3000 20 2500 Mean titer Specificity = 96.9% MEAN = 12% STD = 10% STDs from cutoff = 1.9 Vaccine A 100% 10% The group vaccinated with type B vaccine reached up to 100% of seroconversion with mean titers between 1,500 and 2,500. The groups vaccinated with A and B1 had a seroconversion between 80% and 100%, and mean titers between 1,000 and 2,000. 60 Frequency Graph 2 Competitive Blocking ELISA German SPF chicken population n=612 The IDEXX APV Ab Test detects antibodies from the three commercially available inactivated vaccines against avian pneumovirus 16 days postvaccination and up to 43 days post-vaccination. Graph 5: Percentage of positive samples with the IDEXX APV Ab Test— in chickens vaccinated with inactivated product containing A or B antigen % Positive birds Specificity: German chicken population 10 1500 1000 46 42 38 34 30 26 22 18 14 6 10 2 -2 -6 -1 0 0 2000 500 Blocking 0 x 0 x x x x x 16 23 30 35 43 Days post-vaccination Specificity: U.S. turkey population 60 50 40 30 20 10 e between 0.083 to 0.126 16 14 Vaccine B: Graphs 7 and 8 show a large percentage of positive serum samples from turkeys vaccinated at one-day old with the live vaccine type B. The percentage of seroconversion remains high at six weeks of age, and then starts to decline at 12 weeks of age. 12 10 8 6 4 2 S/P e or 4 0. m 34 0. 28 0. 22 0. 0.1 6 0.1 2 04 0. .0 8 .14 .0 -0 -0 .2 0 -0 Specificity = 51.3% MEAN S/P = 0.09 STD = 0.048 STDs from cutoff = -0.116 Suspect Zone 18 Frequency Graph 4 Indirect ELISA U.S. turkey population n=80 Mean titers for both groups reached levels between 9,000 and 12,000 after the inactivated vaccine was applied. Vaccine B 90% 80% 70% 60% 50% 40% 30% 20% or 4 0. Vaccine A: Graphs 7 and 8 show that there is low seroconversion at three weeks of age with vaccine A, most likely due to maternal antibodies interference. But after the booster with a live vaccine type A, the percentage of turkeys showing titers increases at six weeks of age, as well as at 12 weeks of age. S/P 20 Vaccine A 100% 10% m 34 0. 28 0. 22 0. 0.1 6 04 2 0.1 0. 8 .0 .14 .0 -0 -0 -0 -0 .2 0 The IDEXX APV Ab Test detects antibodies in turkeys vaccinated with live and inactivated avian pneumovirus vaccines against serotype A or B. Graph 7: Percentage of positive samples with the IDEXX APV Ab Test— in turkeys vaccinated with type A or B antigen % Positives Turkey flocks were vaccinated at one day of age with either type A or type B live vaccines. Serum samples (sample size = 23) were taken at three weeks of age. After an additional live vaccination (booster), new serum samples were taken at six weeks and 12 weeks of age, and the last serum sampling occured after an inactivated vaccination at 33 week of age. Cutoff = 0.2 70 0% 3w (1x live) 6w (2x live) 12w (2x live) 33w+ (2x live, 1x killed) Age of sampling (vaccination) Graph 8: Mean titer with the IDEXX APV Ab Test—in turkeys vaccinated with type A or B antigen Vaccine A Vaccine B 14000 Mean titer Specificity = 100% MEAN S/P = 0.021 STD = 0.018 STDs from cutoff = 10.0 80 Frequency Graph 3 IDEXX APV Ab Test U.S. turkey population n=192 -0 The IDEXX APV Ab Test (graph 3) displayed better specificity in a negative U.S. turkey population vs. another commercial indirect ELISA (graph 4). The IDEXX APV Ab Test has an excellent population distribution. The cutoff in graph 3 for the IDEXX APV Ab Test is 0.2, whereas, the arrows in graph 4 indicate the suspect zone for the other indirect ELISA test . Sensitivity: Turkeys with type A and B vaccines 12000 10000 8000 6000 4000 2000 0 3w (1x live) 6w (2x live) 12w (2x live) 33w+ (2x live, 1x killed) Age of sampling (vaccination) IDEXX APV Ab Test Sensitivity: Chickens with type C vaccines Conclusion Seven birds were vaccinated intramuscularly/ subcutaneously with a type C vaccine against avian pneumovirus. Serum samples were taken twice a week for four weeks postvaccination. •The IDEXX APV Ab Test has better specificity than the blocking format or competitive ELISA, which is considered the gold-standard reference for negative populations. Now, poultry producers will have more confidence in monitoring SPF or naïve populations. Graph 9: Percentage of positive samples and mean titers with the IDEXX APV Ab Test—in chickens vaccinated with type C antigen 100% 8000 90% 7000 •The IDEXX APV Ab Test can detect immuno response to a commercially available live or inactivated vaccines against avian pneumovirus that contain A, B or C antigens. 6000 70% 60% 5000 50% 4000 40% 3000 30% Mean titers % Positives 80% 2000 20% 1000 10% 0% 0 0 4 7 11 14 17 21 •The IDEXX APV Ab Test can detect the presence of A, B or C avian pneumovirus. 28 Days post-vaccination •The IDEXX APV Ab Test has a good balance of sensitivity for the detection of A, B or C avian pneumovirus serotypes. •The IDEXX APV Ab Test can be used with xChek* software to generate baselines and to monitor vaccination programs and field challenge interaction. •The IDEXX APV Ab Test has the same sample diluent and same test protocol as the other IDEXX poultry ELISA test kits. The IDEXX APV Ab Test detects antibodies against type C avian pneumovirus 11 days postvaccination. The rate of seroconversion and mean titers are shown in graph 9. At day 14, all birds had seroconverted with a mean titer of 1,400, which increased over time to 7,400 at day 28. For more information about the IDEXX APV Ab Test, please contact your IDEXX representative or visit idexx.com/apv. Corporate Headquarters IDEXX Laboratories, Inc. One IDEXX Drive Westbrook, Maine 04092 USA Tel: Fax: +1 207 556 4890 or +1 800 548 9997 +1 207 556 4826 or +1 800 328 5461 European Headquarters IDEXX Europe B.V. Scorpius 60 Building F 2132 LR Hoofddorp The Netherlands Asian Headquarters IDEXX Laboratories, Inc. 3F-5 No. 88, Rei Hu Street Nei Hu District 11494 Taipei, Taiwan Tel: +31 23 558 70 00 or +00 800 727 43399 Fax: +31 23 558 72 33 Tel: +886 2 6603 9728 Fax: +886 2 2658 8242 © 2010 IDEXX Laboratories, Inc. 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