Research supporting the Infection Chain TM
in improving disease management
Eduardo Fano, Edgar Diaz, Brian Payne
Where to target for improved disease management
• Minimize Exposure
• Biosecurity
• Flow management
• Antimicrobials
• Maximize Immunity
• Vaccination
• Acclimation
• Lactation management
• Proper nutrition
Exposure
Immunity
Results of improving disease management
• If successful at improving disease management
• Fewer clinical signs
• Respiratory, enteric, reproductive
• Improved production parameters
• Therefore, economic improvements
• Decrease in treatments
• Individual injections
• Mass treatments
11 April 20233
Gilt Source
Gilt Developme
ntSow Herd
FarrowingPiglets Rearing
Wean to Finish
OutputMarket
Infection/Prevention Chain TM – Whole Herd Approach
The Whole Herd Approach (System)
Minimize Exposure andMaximize immunity
Minimize Exposure andMaximize immunity
Minimize Exposure andMaximize immunity
Minimize Exposure andMaximize immunity
Vertical Transmission Management
HT -------------HT---------------HT--------------HT-------------HT
VT
HT -------------HT---------------HT--------------HT---------------HT
HT: Horizontal TransmissionVT: Vertical transmission
Previous research supporting the “Infection Chain” concept
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Examples where the industry has adoptedthe Infection Chain™ and Prevention Chain™ Ascarids
E. coli
Rotavirus
Clostridium
Bordetella
Pasteurella
APP
PRRS
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Examples where the industry has widely adoptedthe Infection Chain™ and Prevention Chain™ Ascarids
Sow Vaccination
Piglet Medication
Early Weaning
Minimizing Sow ExcretionSow Medication
Maximizing Sow Immunity
Minimizing colonization
Minimizing colonization
Minimizing Vertical transmission
Minimizing Horizontal transmission
InterventionObjective Epidemiological effect
Understanding and affecting the pathogen’s transmission-infection partial chain
MEW: Early vertical transmission work
Streptococcus sp
H. parasuis
PRRS
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Examples where the industry has started to adoptedthe Infection Chain™ and Prevention Chain™ PRRS instability in the breeding herd
Defined as evidence of PRRSv circulation and transmission vertically and/or horizontally
Can cause reproductive problems w/ biologic & economic impact
Can lead to weaning of PRRSv positive piglets w/ biologic & economic impactPRRSv Control or Elimination; D.Holtkamp,
George Young Conf., 2012Assessment of economic impact of PRRSv
on U.S. pork producers; D. Holtkamp et.al., JSHAP, 2013
Where we need to widely adopt:Mycoplasma hyopneumoniae
There is so much evidence on the importance of Infection Chain™ in the role of downstream health effects in pigs in regards to
However, as an industry we poorly handle M. hyopneumoniae and quickly forget how important the Infection Chain™ and Prevention Chain™ are for managing the disease in pigs
M. hyopneumoniae will be addressed in detail during the next presentation
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The most logical next diseases to attempt to apply the Infection Chain™ and Prevention Chain™ concept™PCV2
PCV2 Infection Chain™
Darin Madson – AASV 2012
2 of Darin’s Take homes.
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Sows to pigs
Non-acclimated sows to gilts
A systematic whole herd approach (Infection/Prevention
Chain TM) to control swine respiratory diseases
Eduardo Fano, Edgar Diaz, Brian Payne
Piglet Approach System Approach
Gilt Source
Gilt Developm
entSow Herd
FarrowingPiglets Rearing
Wean to Finish
OutputMarket
1.- Production Chain
Gilt Source
Gilt Developm
entSow Herd
FarrowingPiglets Rearing
Wean to Finish
OutputMarket
2.- Infection Chain
HT -------------HT---------------HT--------------HT-------------HT
VT
HT -------------HT---------------HT--------------HT---------------HT
The Whole Herd Approach
HT: Horizontal TransmissionVT: Vertical transmission
Gilt Source
Gilt Developme
ntSow Herd
FarrowingPiglets Rearing
Wean to Finish
OutputMarket
3.- Prevention – Piglet Approach
Vaccination
Gilt Source
Gilt Developm
entSow Herd
FarrowingPiglets Rearing
Wean to Finish
OutputMarket
3. Prevention – Piglet Approach
HT -------------HT---------------HT--------------HT-------------HT
VT
HT -------------HT---------------HT--------------HT---------------HT
Vaccination
Whole herd infection pressureOnly Piglet immunizationNo accomplishment of Minimizing exposure
HT: Horizontal TransmissionVT: Vertical transmission
Gilt Source
Gilt Developm
entSow Herd
FarrowingPiglets Rearing
Wean to Finish
OutputMarket
4.- Prevention – Whole Herd Approach (System)
The Whole Herd Approach (System)
Minimize Exposure andMaximize immunity
Minimize Exposure andMaximize immunity
Minimize Exposure andMaximize immunity
Minimize Exposure andMaximize immunity
Vertical Transmission Management
Gilt Source
Gilt Developm
entSow Herd
FarrowingPiglets Rearing
Wean to Finish
OutputMarket
5.- Infection/Prevention Chain – Whole Herd Approach
The Whole Herd Approach (System)
Minimize Exposure andMaximize immunity
Minimize Exposure andMaximize immunity
Minimize Exposure andMaximize immunity
Minimize Exposure andMaximize immunity
Vertical Transmission Management
HT -------------HT---------------HT--------------HT-------------HT
VT
HT -------------HT---------------HT--------------HT---------------HT
HT: Horizontal TransmissionVT: Vertical transmission
The M. hyopneumoniae infection chain
• Clinically Mhyo associated respiratory disease in growing- finishing units
• Nursery piglets exposure
• Prevalence at weaning
• Sow herd instability/Vertical transmission
• Gilt Mhyo management
Level 1
Replacement animals
Gilts as risk factor for Respiratory disease
• Maes et al, 1999. Risk indicators for the seroprevalence of Mycoplasma hyopneumoniae, porcine influenza viruses and Aujeszky's disease virus in slaughter pigs from fattening pig herds.
• Maes et al., 2000. Herd factors associated with the seroprevalences of four major respiratory pathogens in slaughter pigs from farrow-to-finish pig herds.
• Meyns T et al., 2011. A cross-sectional study of risk factors associated with pulmonary lesions in pigs at slaughter
• Nathues H, 2012. Herd specific risk factors for Mycoplasma hyopneumonie infections in suckling pigs at the age of weaning.
Persistence of M. hyopneumoniae
Principals (Inoculated)
Sentinels (14 days Exposure time)
• Introduction of replacement gilts into the breeding herd
• This could results in a continuous infection
• This process probably leads to a high prevalence of M. hyopneumoniae.
• Perpetuating the disease in the breeding herd
Level 2
Sow herd
Mhyo sow herd infection dynamics = Vertical transmission rate = Prevalence in piglets at weaning
0
10
20
30
40
50
60
1 2 3 4 5 6 7 8 9 10 11 Average
Groups
Pre
vale
nce
(%)
Fano et al., 2007
Parity distribution as a potential factor
Group # A (1-2)B (3-
4)C (>
5)
1 59.9 20.51 20.51
2 46.15 17.94 38.89
3 38.46 28.2 33.3
4 38.46 30.7 30.7
5 53.84 20.51 25.64
6 48.7 30.7 20.51
7 46.15 25.64 28.2
8 35.89 43.58 20.51
9 25.64 46.15 28.2
10 30.7 38.89 33.3
11 28.2 38.46 30.7
Average 41.10 31.03 28.22
0
10
20
30
40
50
60
70
1 2 3 4 5 6 7 8 9 10 11
Avera
ge
Groups
%
A (1-2)
B (3-4)
C (> 5)
Level 2
Sow herd
Level 3
Wean to finish pigs
Vertical transmission
Vertical Transmission/Horizontal Transmission
Only one event: Infection Chain
Pre weaningExposure
NurseryExposure
FinishingExposureand clinical disease
Infective sows
Vertical Transmi
ssion
Negative Gilts
Sow Herd
Infection Pressure
Active shedding Gilts
Piglet Day 0
Prevalence of Mhyo in piglets at weaning Initial prevalence
0
10
20
30
40
50
60
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Groups
%
* Fano et al., 2007
0 20 40 60
0
5
10
15
Ave
rage
Lung L
esio
n S
core
Prevalence at weaning (N-PCR, Nasal)
R-squared= 0.5304, P-Value= 0.0009
C1
C2
* Fano et al., 2007
Correlation of prevalence at weaning with severity of the disease in finishing
populations
11 April 2023PLEASE INSERT Presentation title 42
Level 3
Wean to finish pigs
Agent spread: Nursery and Finishing
Prevalence at weaning constitutes the initial microbial load of the piglet batch
This will growth by horizontal (internal) and/or lateral (external: next barn or next
farm) transmission.This is a slow process and would take until
finishing to show clinical manifestation on the population
Proper pig flowPiglet Vaccination
Proper and moderated medication
The order of the epidemiological events
Sow herd Infection pressure
Vertical transmission
Prevalence at weaning
Nursery piglets exposure
Finishing pigs disease
0 20 40 60
0
5
10
15
A
vera
ge
Lung L
esio
n S
core
Prevalence at weaning (N-PCR, Nasal)
R-squared= 0.5304, P-Value= 0.0009
C1
C2
* Fano et al., 2007
Vaccinated piglets and “lack of efficacy of the vaccine”
Vaccinated piglets and “No lack of vaccine efficacy compliance”
Piglet Vaccination Challenge: Vertical/Horizontal
Gilt Source
Gilt Developm
entSow Herd
FarrowingPiglets Rearing
Wean to Finish
OutputMarket
Infection/Prevention Chain TM – Whole Herd Approach
The Whole Herd Approach (System)
Minimize Exposure andMaximize immunity
Minimize Exposure andMaximize immunity
Minimize Exposure andMaximize immunity
Minimize Exposure andMaximize immunity
Vertical Transmission Management
HT -------------HT---------------HT--------------HT-------------HT
VT
HT -------------HT---------------HT--------------HT---------------HT
HT: Horizontal TransmissionVT: Vertical transmission
Conclusions
• Minimizing Exposure– Gilt Management– Sow herd stability– Pig flow– Immunity
• Maximizing Immunity– Natural exposure– Vaccination to modulate clinical impact