Dr. Julio Alverez - Impact of PED in Growing Pigs

Julio Alvarez, Javier Sarradell, Robert Morrison, Andres Perez

DVM, PhD

Department of Veterinary Population Medicine

College of Veterinary Medicine

University of Minnesota

Impact of PED in growing pigs

PED impact

• Primarily due to losses in suckling piglets– Mortalities between 50-80%b – Time to recover baseline production of

>10 wksc

• Further impact?– Infected growing pigs: 1-3% mortalityb

– Pigs exposed to PED as piglets that make it to the growing phase?

a Swine enteric Coronavirus disease testing summary report, Sept 3 2014b White Paper (Geiger and Connor, 2013)c Swine Health Monitoring Project (Goede and Morrison, 2014)

a

Objective

• To quantify the impact of PEDv infection in growing pigs by comparing– Mortality– Average daily gain (ADG)– Average daily feed intake (ADFI)– Feed conversion rate (FCR)

in batches exposed/unexposed to the virus

Peek at the results

• Impaired performance of pigs from first PED+ batches compared with PED- pigs– Increased mortality (6-18%)–Decreased ADG (0.07-0.26 lb/day)– Increased FCR (0.3-0.8)

Material and methods

• Screening of productive records to select batches from positive flows– Only nursery/WF batches

• Selection of 33 flows– 11 nursery– 22 WF

Commercial sow

Nursery

FinishingWean to

finish

PED detection

• Selection of first PED+ batch within a given flow (“infected” batch)

• Selection of the closest preceding PED- batch from the same flow (“control” batch)– At least 14 days before the infected batch (increase

specificity)– Not more than 4 months before the infected batch

Inclusion criteria

PED+ batch

Control batch (closest available)

Weeks

Data analysis

• Pairs of batches - paired non-parametric comparison (Wilcoxon test) of performance records

• Comparison of nursery to WF paired differences (Mann-Whitney test)

Study population• 18 flows fulfilled the inclusion criteria (18 case + 18

control batches)– 4 nursery– 14 WF (double stocking: first stage in growing, ≈60d)

• Average mortality, ADG, ADFI and FCR in the previous four months (before PED) within normal limits

Descriptive results• First PED+ batch change in trends

– Increase in mortality (4.9 to 15.2%)– Decrease in ADG (0.79 to 0.72)– No change in ADFI– Increase in FCR (1.75 to 2.28)

• GRAFICA GLOBAL

4 3 2 1 PED!

Paired comparison• Mortality

Control Infected

12.5% increase (95% CI: 6.4-18.4)

• Performance

Control Infected Control Infected Control Infected

ADG ADFI

FCR

↓0.16 lb/d↑ 0.55

So, as previously mentioned…

• Impaired performance of pigs from first PED+ batches compared with PED- pigs– Increased mortality (6-18%)–Decreased ADG (0.07-0.26 lb/day)– Increased FCR (0.3-0.8)

Conclusions (II)• Caveats of the study

– Reduced dataset – No adjustment by covariates (site)

• However…– Robust trend suggesting a decreased performance of

growing pigs from PED+ batches• Increase in mortality (6-18%... Or more!)• Decrease in ADG, ADFI unaffected Increase in FCR (0.3-0.8)

– Rough numbers: with 0.3$/lb feed from wean to 40 lbs, 0.55 poorer FCR costs approx $0.16/lb gain

• Impact of PEDv goes beyond suckling piglets

Questions?jalvarez@umn.edu

Thank you very much for your attention

Dr. SarradellDr. Morrison

Dr. Perez