Sow Herd Monitoring Tools in PRRSv Control Programs PRRS Diagnostic and Control Workshop Thessaloniki, Greece. August, 2012 Jose Angulo DVM Boehringer Ingelheim Animal Health GmbH – Global PRRS Solutions

Outline  PRRSv Sow herd stability  Measurement tools  Applications (sharing field examples)

PRRS control / Sow Herd Stability  Prevent Infection  Maximize Herd Immunity  Minimize Exposure Definition: Absent of clinical signs attributed to PRRSv and NO EVIDENCE of resident virus circulation within the population. = Weaning PCR negative pigs. * *Gillespie(2003), Dufresne (2004)

First milestone in PRRSv control: To Achieve Sow Herd Stability

Using dx test as monitoring tool  Goal of testing  Accuracy and Confidence level  Cost of the sampling and testing  Frequency of the sampling Vs size sampling  Characteristics of the test (Sp,Se)

Using ELISA IDEXX Herd Check  Commercial kit (Standard)  Reliable and well implemented across D-Labs.  Costless vs PCR Keep in mind:  Measure Exposure, NO protection.  Consistent absent of anamnesic Ab response in present of complete protection vs disease ( ab ≠ protection)  Unable to differentiate Field exposure vs Vaccine  Seropositive pigs become seronegative overtime or following repeated vaccination Murtaugh (2005)

Measuring sow herd stabilization Serum Profiles. ELISA (IDEXX Herd Check) measures exposure. –Population test –SP value average (>0.4 +) –SP value Standard Variation StD –% Positive Reduce Resident virus circulation within Sow Herd & Weaning negative pigs. Gradual (%)

Understanding the serological picture with ELISA Idexx Days in GDUD0D28D77 Standard Dev Replacement naive gilts batches LVI in GDU (n=35) Angulo, Private practice, 2003

Understanding the serological picture with ELISA Idexx Abril-05 Octubre - 05 SP Avg2.393 a b b b Stand Dev % Positive Sow herd serum profile monitoring along the line with MLV mass vaccinations. Angulo, IPVS proceedings, 2006 n=35 (Parity structure)

Applying quality tools in the analysis: Box Plot.  Data exploration tool to analyze and find trends and relationships identifying unique characteristics of the data analyzed. Facilitating its description and interpretation. Daniel (2004). Biostats, 4th ed. NWA Quality Analyst Software JMP Software

Using Box Plot in Serology Profiles  Information about: Shape, Dispersion and Center of the data. » Central Tendency » Dispersion stats » Skew » Outlying Measurements » Quick look at expected values Smallest Value 25 th Percentile 50 th Percentile 75 th Percentile Median Mean Largest Value Interval coefficient Outlier MINITAB, 2012

Sow Herd PRRSv serology

PRRSv Serology after PRRSv program implementation

PRRSv Serology: Outbreak Recovery picture (4,500 sows)

PRRSv Serology: Outbreak picture

Monitoring control strategies Context: 2,000 sows FF farm. Mass Vx every 6 months (04) Mass Vx every 3 months. Angulo, AMVEC, 2006

Home take messages  Tools for measuring sow herd stability are available  Understanding of diagnostic tests is critical  Add all measurements to bring the general picture  Link tools with goals  Simple tools like Box Plot can add value to the analysis, interpretation and decision making process. » Statistic Software or Excel!!

Thanks for your attention