Dr. David Baumert - In-Field Research & PCV2 Sow Herd Stability: Our Process

In-Field Research & PCV2 Sow Herd Stability: Our Process
© Copyright Cargill, Incorporated 2012. All rights reserved.
1
In-Field Research &
PCV2 Sow Herd Stability:
Our Process
Dr. David Baumert
February 28, 2014
Dallas, Texas

Veterinarian’s Oath
• Being admitted to the profession of veterinary medicine, I
solemnly swear to use my scientific knowledge and skills
for the benefit of society through
– the protection of animal health and welfare,
– the prevention and relief of animal suffering,
– the conservation of animal resources,
– the promotion of public health and
– the advancement of medical knowledge.
• I will practice my profession conscientiously, with dignity
and in keeping with the principles of veterinary medical
ethics.
• I accept as a lifelong obligation the continual improvement
of my professional knowledge and competence.
2

Questions and thought process
• What is the Infection Chain™ of PCV2 in our herds?
– Clinically, subclinically
– What are our expectations of PCV2 control?
• How does vertical transmission of PCV2 impact our growing pigs?
– Does it matter?
– What tools do we have to determine status?
• How do we intervene to make an impact on PCV2?
– How do we measure impact?
– Is the intervention successful?
– What is the ROI?
3

Evidence-based decision making
4
Domains that influence evidence-based decision making. Source: Satterfield JM et al.

Example of Cargill Pork flow to put
discussion into perspective
5
12 Stand-alone Gilt grower sites; rotational, all-in/all-out fill
Gilt Developer/Breeder
continous flow, multi-source
16 Stand-alone, 700-head sow farms
20,000 head, 6-farm, sow system
Commercial nursery system (multi-sourced) Commercial nursery system (multi-sourced)
Commercial finisher system (multi-sourced) Commercial finisher system (multi-sourced)
INTERNALNUCLEUS / MULTIPLICATION

Our PCV2 Infection Chain™
6

Sampling for Sow Herd Stability
• Pigs/Fetuses
– Fetal Hearts
– Pre-suckle Serum
– PUCS – Placental Umbilical Cord Serum
• Sows
– Oral fluid
– Serum
• Environment
– Swabbing
7

Placental umbilical cord blood (PUCS)
Photos courtesy of Tom Fangman, Tyler Te Grotenhuis

Progression of PUCS sampling
9
Validation of PUCS
Intra-herd variation
Validation of PUCS
Inter-herd variation
Sampling protocol

PUCS – Placental umbilical cord serum
Baumert, Leman 2013
0
10
20
30
40
50
60
70
80
90
100
Sow Serum Litters ≥ 1 pig
pos.
PUCS Enviro. Cloth
PercentPositive,%
Site A Site B
53 PCV2 positive pre-suckle pigs out of 168 pigs tested (31.5% positive)
17 PCV2 placenta positives out of 21 litters tested (81% positive)
Average of 32.1% pigs PCV2 positive/litter (Range 0% to 100% positive/litter)

11
Validation of PUCS
Validation of PUCS
Sampling protocol
Sampling protocol
Impact on Performance
Risk Factors

How many sampling periods are needed?
One-way ANOVA Analysis of Variance P<0.001
The variance in the
level of viremia in
positive PUCS samples
over time
is significantly different
30 day 30 day
Farm A

Percent positive PUCS samples per
three 30 day time periods per 6 farms
13
0
20
40
60
80
100
A B C D E F
Percentpositive,%
Farm ID
Period 1 Period 2 Period 3

88%
90%
92%
94%
96%
98%
100%
A B C D E F
Live born percent Conception Rate, %
Performance of the herd populations tested
14
20%
40%
60%
80%
100%
120%
140%
160%
180%
A B C D E F
Still born, % from mean
Mummies, % from mean
• Conception rates were similar between sites
• B, C and D farms had lower Live Born
(as a percentage of total born) than A, E, F
• B, C, D were 3 highest stillborn and mummies
Stillborn and mummies,
percent deviation from group mean, %
Live born and conception rate
percent, %
* Live born percent = live born mean / total born mean

Can we make an impact on stability?
• Options for making an impact
– Biosecurity
• Internal biosecurity – McRebel™
– Herd Closure
– Gilt Acclimation
– Vaccination
15

0%
20%
40%
60%
80%
100%
1 2 3 4 5 6 7
PercentPositivePUCSsamples,%
Month Sampled
Farm B Farm C Farm D Farm E
Interventions and the impact
16
Closed the herd
Mass vaccination
Mass vaccination
Control herd
no action taken

Where does instability of the sow herd start
17

Gilt development and PCV2 – first look
• Initial finding into GDU supplying PCV2 unstable sow herd
– Negative (by serum PCR) gilts are entering the GDU
• Hypothesis: negative or naïve gilts entering the sow herd may be
amplifying PCV2 instability in the sow herd
• Incomplete evidence: herd closure in 1 herd coincided with herd
stabilization
18
0%
20%
40%
60%
80%
100%
1 2 3 4 5 6 7
Farm B

Summary – findings and observations
• PCVAD is not a big concern in PCV2 vaccinated pigs in our system
– Vaccination works
• Vertical transmission occurs in all herds tested
– Levels vary
• PUCS sampling is a good sample to test for sow herd stability
– More positives found than with sow serum
• PCV2 was widely present in the environment
• A minimum of 3 sampling periods are necessary
– More might be needed…further evaluation is needed
19

Summary – findings and observations (cont)
• In 3 herds that had highest measured PUCS positive samples:
– Similar conception rates
– Fewer live born percentage, higher mummies and stillborns
• Interventions (herd closure and mass vaccination with CircoFLEX®
coincided with detection of stabilization
– Repeatability needs to be tested
• Gilt (in gilt development) surveillance and projects are ongoing
20

Summary - beliefs
• Current PCV2 vaccines protect pigs through marketing
– We are only trying to tweak, and optimize PCV2 control
• The Infection Chain™ and vertical transmission with PCV2 is real
• Additional work is required to determine the production and economic
impact, if any, of PCV2 presence at birth
• The risk factors for PCV2 sow herd stability/instability are
unclear to date
• We will continue to work on PCV2 at the gilt, sow and pig levels
21

22
Validation of PUCS
Validation of PUCS
Sampling protocol
Impact on Performance
Risk Factors
Risk Factor Analysis
Research herd inclusion criteria

Dr. David Baumert - In-Field Research & PCV2 Sow Herd Stability: Our Process

Empfohlen

Empfohlen

Weitere ähnliche Inhalte

Ähnlich wie Dr. David Baumert - In-Field Research & PCV2 Sow Herd Stability: Our Process

Ähnlich wie Dr. David Baumert - In-Field Research & PCV2 Sow Herd Stability: Our Process (20)

Mehr von John Blue

Mehr von John Blue (20)

Dr. David Baumert - In-Field Research & PCV2 Sow Herd Stability: Our Process