Mycoplasma hyopneumoniae“Infection Chain”

Eduardo Fano DVM MS PhDBIVISwine Technical Manager Americas

What is the current Mhyo infection picture?

• Clinically Mhyo associated respiratory disease in growing- finishing units

• In some cases there is a perception of lack of efficacy of vaccination protocols

• Are we over focusing the strategy just in the piglet?

• Are we looking at the “ whole herd’ infection picture of the disease? Are we understanding the “root’ of the problem?

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 vaccinated finishing pigs

Mycoplasma hyopneumoniae “Infection Chain”

Level 1

Replacement animals

Level 2

Sow herd

Level 3

Wean to finish pigs

Horizontal transmission

Vertical transmission

Horizontal transmission

Lateral

spread

External-Gilts+Gilts

Local Replacement

Fano et al., 2007

Level 1

Replacement animals

Persistence of infection/shedding“The key factor”

Level 2

Sow herd

•Incoming gilts exposure/protection status

•Incoming gilts shedding status

•Sow herd instability

Sow herd instability

Consequence of sow herd instability:More sow to piglet transmission (prevalence at weaning) and

variability between groups

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

Level 2

Sow herd

Level 3

Wean to finish pigs

Vertical transmission

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

The consequence of higher vertical transmission:Higher the prevalence at weaning higher the clinical

impact of Mhyo in finishing pigs

Vertical Transmission/Horizontal Transmission

Only one event: Infection Chain

Piglet Day Piglet Day 00

Level 3

Wean to finish pigs

•Prevalence at weaning

•Horizontal transmission rate downstream

•Pig flow and W to F management

•Piglet immunization

•Piglet medication

The infection chain