Download presentation
Presentation is loading. Please wait.
Published byPhebe Dennis Modified over 9 years ago
1
Evaluation of the efficacy of one dose of autogenous MJPRRS vaccine in nursery pigs Dr. Mark Wagner, DVM Fairmont Veterinary Clinic Fairmont, MN
2
Purpose of study Gain a better understanding of the role and efficacy of using the autogenous MJPRRS vaccine in controlling or managing PRRS virus
3
Trial data to be presented Trial #1 – Vaccination of PRRS naïve pigs at 21 days of age and challenge with field virus at 32 days post vaccination Trial #2 – Similar repeat of trial #1, pigs challenged at 28 days post vaccination Trial #3 – Vaccination of PRRS viremic pigs at peak viremia
4
Trial design Challenge material – Virulent field virus with a 1-18-2 RFLP Group D-4 under MJPRRS virus grouping system Preparation of virus material – A 21 day old PRRS naïve pig inoculated with the 1-18-2 field virus – Serum collected 5 days post inoculation and frozen – An aliquot of serum inoculated on cell culture and harvested 7 days later, then frozen
5
Trial design Analysis of challenge material – Sequencing completed to confirm 1-18-2 virus – Quantitative PRRS PCR’s completed along with TCID 50 ’s Inoculum material ORF6-copies per ml Calculated IVP’s per ml TCID 50 Serum10 9 2,34110 2 Cell Culture10 24,41610 3
6
Trial design Challenge dose – Trial #1 0.5ml IM plus 0.5ml IN (serum material = 100 viruses) (culture material = 1,000 viruses) – Trial #2 0.5ml IM plus 0.5ml IN (culture material = 1,000 viruses) – Trial #3 0.05ml IM plus 0.5ml IN (serum material = 55 viruses)
7
Trial design Vaccination protocol – Treatment group MJPRRS – 2ml dose that included 10% extra adjuvant (final 20%) Mycoplasma – 2ml dose – Control groups Mycoplasma – 2ml dose
8
Trial design Data collection included – Body temperature – Virus replication based on PRRS Q-PCR’s – Mortality – Average daily gain weight
9
PRRS virus replication data: Data compiled for Trial #1, Trial #2, and Trial #3
10
Summary PRRS virus replication in MJPRRS vaccinated compared to non-vaccinated 21 day old PRRS naïve pigs when challenged to a field virus at 53 and 49 days old (Trial #1 & #2 data) Serum ChallengedCulture Challenged Days Post Challenge VaccinatedNon–VaccinatedVaccinatedNon–Vaccinated ORF6 copies*IVP # ORF6 copiesIVPORF6 copiesIVPORF6 copiesIVP 5 1.8 x 10 9 7042.8 x 10 9 1,1181.3 x 10 9 -------------- 9.3 x 10 8 674 ----------- 367 2.2 x 10 9 --------------- 8.4 x 10 8 867 ---------- 328 11 6.4 x 10 7 252.7 x 10 8 1061.1 x 10 8 -------------- 4.2 x 10 7 44 ----------- 16 2.1 x 10 8 --------------- 7.2 x 10 7 83 ---------- 28 23 5.4 x 10 5 0.212.0 x 10 6 0.792.2 x 10 6 -------------- 5.1 x 10 6 0.88 ----------- 1.9 1.4 x 10 6 --------------- 2.1 x 10 6 0.50 ---------- 0.80 * ORF6 Copies per ml by Quantitative PCR # Infective Virus Particles calculated per ml based on Q-PCR
11
Summary of PRRS virus replication in 26 day old PRRS viremic pigs vaccinated with MJPRRS vaccine at the peak of viremia compared to non-vaccinated controls (Trial #3 data) Serum Challenged then VaccinatedNon-Vaccinated ORF6 Copies*IVP # ORF6 CopiesIVP 5 Days post challenge (Day of vaccination) 3.5 x 10 9 1,3553.3 x 10 9 1,144 7 Days post challenge (2 Days post vaccination) 5.2 x 10 9 2,0795.6 x 10 9 2,215 14 Days post challenge (7 Days post vaccination) 3.5 x 10 8 1031.2 x 10 9 488 24 Days post challenge (10 Days post vaccination) 1.8 x 10 8 555.5 x 10 8 123 * ORF6 Copies per ml by Quantitative PCR # Infective Virus Particles calculated per ml based on Q-PCR
12
Average daily gain data: Data compiled for Trial #1 and Trial #2
13
Summary of Average Daily Gain (ADG) performance in MJPRRS vaccinated compared to non-vaccinated 21 day old PRRS naïve pigs when challenged to a field strain of PRRS at 53 days of age (Trial #1 data) Day 1Day 32 post arrivalDay 55 post arrivalOverall Day ofVaccinationChallenged* Day 1-23 post challengeDay 1-55 arrival Weight (Ibs)Average ADGAverageADG # ADG Vaccinated 14.536.50.7154.00.76 0.74 Non- Vaccinated 16.032.50.5353.00.890.68 * All pigs challenged with PRRSv at 32 days post arrival (53 days of age) # ADG affected by mortality; Vaccinated group, 1 of 22 dead Non-vaccinated group, 4 of 22 dead
14
Summary of Average Daily Gain (ADG) performance in MJPRRS vaccinated compared to non-vaccinated 21 day old PRRS naïve pigs when challenged to a field strain of PRRS at 49 days of age (Trial #2 data) Day 1 Day 28 post arrival Day 40 post arrival Day 54 post arrival Overall Day of VaccinationChallenged* Day 1 – 11 post challenge Day 11 – 24 post challenge Day 1-54 arrival Weight (Ibs)Average # AverageADGAverageADGAverageADG Vaccinated 13.731.20.6234.20.2749.01.140.74 Non- vaccinated 14.235.50.7637.60.1948.00.800.52 * All pigs challenged with PRRSv at 28 days post arrival (49 days of age)
15
Mortality data: Data compiled for Trial #1, Trial #2, and Trial #3
16
Summary of Mortality in MJPRRS vaccinated compared to non- vaccinated 21 day old pigs when challenged to a field strain of PRRS at 53 or 49 days of age (Trial #1 and #2 data) Trial #1 Challenge material Treatment groupMortality at 23 days post challenge Serum Non-Vaccinated3 of 11 (27%) Vaccinated1 of 11 (9%) Culture Non-Vaccinated1 of 11 (9%) Vaccinated0 of 11 (0%) Trial # 2 Challenge material Treatment groupMortality at 23 days post challenge Culture Non-Vaccinated0 of 16 (0%) Vaccinated0 of 16 (0%) Overall mortality for non-vaccinated groups, 18.2% Overall mortality for vaccinated groups, 4.5%
17
Summary of Mortality in 26 day old PRRS viremic pigs vaccinated with MJPRRS vaccine at peak viremia compared to non-vaccinated controls (Trial #3 data) Trial # 3 Challenge material Treatment groupMortality at 10 days post vaccination* Serum Non-Vaccinated3 of 12 (25%) Vaccinated2 of 12 (16%) * 15 days post challenge
18
Summary (I) Virus Replication – For trial #1, a statistical reduction in virus replication shown between the MJPRRS vaccinates compared to the non-vaccinates at days 5 and 11 post challenge (p value = 0.04 and 0.0098, respectively) – For trial #2, no statistical difference noted – For trial #3, a statistical reduction in virus replication during vaccination at peak viremia at day 7 and 10 post vaccination (p value = 0.048 and 0.002, respectively)
19
Summary (II) Average Daily Gain (ADG) – For trial #1, no statistical difference noted Numerically:Vaccinates, Day 1-23 post challenge, 0.76 Non-Vaccinates, Day 1-23 post challenge, 0.89 High mortality in non-vaccinates likely affected ADG differences in calculation – For trial #2, A statistical difference (p value = 0.026) between MJPRRS vaccinated group vs. controls during Day 1-24 Numerically:Vaccinates, Day 1-24 post challenge, 0.74 Non-Vaccinates, Day 1-24 post challenge, 0.52
20
Summary (III) Mortality – For trial #1 Vaccinates = 1 of 22 (4.5%) Non Vaccinates = 4 of 22 (18%) – For trial #2 No mortality in either group – For trial #3 Vaccinates = 2 of 12 (16%) Non Vaccinates = 3 of 12 (25%)
21
Conclusions Data demonstrated that PRRS naïve or viremic pigs were able to respond to one dose of autogenous MJPRRS vaccine with extra adjuvant. A reduction on virus replication was statistically demonstrated (2 of 3 trials). A numerical improvement in ADG was demonstrated (2 of 2 trials). A statistical difference noted also (1 of 2 trials). A numerical improvement in Mortality was demonstrated (2 of 3 trials).
22
Thank you
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.