1. The prevalence and trends of economically important porcine production diseases in Northern Ireland
Natalie Brush
3rd Year PhD Student
Supervisors: Dr. John McKillen (AFBI) and Dr. Ultan Power (QUB)
Note: Do not change background, font or font colours.

2. Project aims
This work is part of a larger study that is focusing on the extent of pleurisy in Northern Ireland pigs by examining the associated microbiological, management and environmental risk factors
How much is there in NI?
Determine the prevalence of pleurisy (and other conditions) in Northern
Ireland pig herds
What causes it?
Identify the microorganisms involved and assess the farm management,
and environmental risk factors for pleurisy
3. How much does it cost the industry?
Determine the economic impact of pleurisy in pigs
This work is part of a larger study. What I will be talking about today is the prevalence of pleurisy and other production diseases in NI. This is the focus of this presentation.

3. Background = Economic losses
Meat inspection is the visual inspection of carcass and offals for the purpose of:
(a) Ensuring that all meat entering the food chain is fit for human
consumption
(b) To ensure all meat is free from disease and does not pose a threat to
human health
Inspection of meat post-slaughter provides an opportunity for pig herd health to
be assessed
Porcine production diseases result in;
Reduced growth
Reduced feed efficiency
Reduced carcass quality
= Economic losses

4. Lesion Monitoring Data set 1 (Individual pig pathologies) 90,938 pigs
1145 batches
Data set 2 (Average prevalences)
10 seasons from 2008 to 2012
6 seasons from
Dealing with two data sets. Data set 1 is indiviual pig data from
Data set 1: As part of the Pig ReGen pig health and welfare checks, lesion monitoring occurs in abattoirs 3 times a year (spring, summer and autumn) where 8 different lesions are scored.
Data set 2 is average prevalence data only for these 8 lesions over 7 years.

5. Macroscopic lesions Respiratory Enzootic pneumonia-like (EP)
Pleurisy (PL)
Pleuropneumonia (PP)
Lung abscesses
EP – areas of lung consolidation
PL – fibrous adhesions between lung and between lung and chest wall
PP – focal areas of lung consolidation
Lung abscesses – Localised areas in the lung
Pictures taken from BPHS/BPEX lesion scoring information leaflet

6. Macroscopic lesions Non-Respiratory Pericarditis Milk spot liver
Papular dermatitis (PD)
Tail bite
Peri – inflammation of the pericardium
Milk spots – white spots of healing tissue on the liver
PD – red papules on the skin
Tail bite – damage to the tail
Pictures taken from BPHS/BPEX lesion scoring information leaflet

7. Scoring System Lesion Pathology Scoring system Enzootic pneumonia
Red/tan/grey lung consolidation affecting the cranioventral regions
Goodwin-Muirhead 55 point scoring system (Goodwin et al., 1969)
Pleurisy
Fibrinous or fibrous adhesions on the lung and/or between the lung and chest wall
0 (no lesions) to 5.
Score increasing with severity.
Pleuropneumonia
Focal areas of lung consolidation usually affecting the caudal lobes
Presence/Absence
Lung abscess
Localised abscess within the lung
Pericarditis
Fibrinous or fibrous adhesions on the pericardium
Milk spots
White areas of healing foci on hepatic tissue
Papular dermatitis
Red papules found widespread across the skin
0 (no lesions) to 3.
Tail bite
Damage to the tail (recent or old)
Scoring system is binary for all conditions except EP (goodwin-murihead 55 point scoring system), PL (0-5 scoring system) + PD (0-3 scoring system).
Scores increasing with severity.

8. The prevalence of porcine production diseases in Northern Ireland pig herds
Established the prevalence of all the different conditions monitored at slaughter.
1. Animal level prevalence – milk spot lesions are the most prevalent condition with 16% of animals presenting with lesions at slaughter. Followed by pleurisy at under 10% and then pneumonia lesions. All other conditions affect <5% of animals.
2. Herd level prevalence – pleurisy is the most prevalent condition affecting just under 75% of herds (three-quarters of all herds in NI). This is followed closely by pericarditis. Milk spot lesions are the third most prevalent disease and pneumonia the fourth.

9. How does the NI data from 2013/14 compare to the rest of the UK?
EP is lower in NI (6.69%) than England and Wales and Scotland between , 22.7% and 29% respectively
Pleurisy lesions in NI (11% of pigs in 2012, 9.21% across ) are similar to those observed in England and Wales (11.53% in 2012) and lower than in Scotland (15.47% in 2012)
Pleuropneumonia and lung abscess were reported at very low levels and are similar to those prevalences reported for the rest of the UK
A recent publication by Eze et al., 2015 compared the respiratory lesions across 3 monitoring systems (E&W, NI & Scotland).
What we have reported is lower levels of EP that E&W and Scotland. Similar PL levels to E&W but lower than Scotland.
Similary low levels of PP + lung abscesses

10. The prevalence of porcine production diseases in Northern Ireland pig herds
Probability of significance for correlations between lesions types recorded in pigs at slaughter in Northern Ireland ( ).
Lesion
Enzootic pneumonia
Pleurisy
Pleuro-pneumonia
Pericarditis
Lung abscess
Milk spot
Papular dermatitis
Tail bite
Enzootic
pneumonia -
<0.001
0.0083
0.0034
0.0021
0.0307
0.0052
Papular
dermatitis
Correlations observed between lesions at slaughter.
Correlations seen between respiratory lesions, parasitic lesions and between pleurisy and tail bite lesions.

11. The prevalence of porcine production diseases in Northern Ireland pig herds
These two graphs show the changes in prevalence over time.
The pathologies are separated just based on scale on the vertical axis, for convenience.
Top graph displays the most prevalent conditions – a decrease in EP + an increase in pericarditis.
Bottom graph displays the least prevalent conditions – decrease in lung abscesses.

12. †Pleuropneumonia lesions were not recorded prior to autumn 2009
Trend in lesion prevalence observed over 16 seasons from pigs slaughtered in Northern Ireland ( )
Lesion
Probability
Trend
Enzootic pneumonia
<0.001*
Negative
Pleurisy
0.253
None
Pleuropneumonia†
0.995
Lung abscess
0.007*
Pericarditis
0.003*
Positive
Milk spots
Papular dermatitis
0.083
Tail bite
0.334
Mann-Kendall time trend analysis performed on AVERAGE prevalences only (data set 2) and also included additional average prevalences from seasons
Trend analysis was taken over 16 seasons from autumn 2008 to autumn 2014.
Statistically significant results for a decrease in EP over time in NI.
Also found a decrease in lung abscesses and an increase in pericarditis over time, but on a much smaller scale.
No trend with any of the other conditions, including pleurisy.
†Pleuropneumonia lesions were not recorded prior to autumn 2009

13. Summary
Determined the prevalence of 8 economically important production diseases at both animal and herd level
Established that relationships exist between different lesion types
Decrease in enzootic pneumonia-like lesions and lung abscesses over the past 7 years ( ) and an increase in pericarditis lesions

14. Future work Take home message
Commencing a longitudinal/environmental study to further investigate the pathogens involved with pleurisy and their infection dynamics on farms
Farm management survey
Calculate the economic cost of pleurisy
Take home message
We hope to be able to inform the industry as to the extent and causes of porcine production diseases in NI
The economic element to the study will allow producers to do a cost/benefit analysis on the introduction of preventative measures

15. Acknowledgements
Dr. John McKillen (AFBI) and Dr. Ultan Power (QUB) Porcine Virology Team at VSD Department of Agriculture and Rural Development (DARD) Jesus Borobia and Dermot Sparrow at Moss Vet Clinic AFBI Biometrics Howard Tonks and Pig ReGen Ltd.