03 pcvd g perreul

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4TH MERIAL FORUM

HAVE WE GOT PCVD &

SWINE INFLUENZA UNDER

CONTROL?

PCV2 serological status of gilts at their arrival in commercial

farms

Dr G. PERREUL, Dr B. BOIVENT and Dr J.-B. HERIN

MERIAL SAS, St Herblon, France

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Content

• Replacement gilts: why is it important to know their PCV2 status?

• PCV2 gilt status in France: results of a field survey

• Impact of CIRCOVAC vaccination on gilts: a field example

• Conclusion: how to manage PCV2 immunity status in replacement gilts?

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Context: replacement gilts

• Quarantine is a crucial step for future breeders: –observation –adaptation –growth

• PCV2 antibody titers are indicative of: – immune status –ability to resist to a new PCV2 exposure

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Context: is there a risk to gather in gilts with low PCV2 Ab titers?

• Sarli G. et al., ESPHM 2010, Hannover

– the gilt with the lowest anti-PCV2 antibody titer showed:

• the highest number of positive tissues and fetuses

• the longest lasting viremia

Objective

• To assess PCV2 antibodies level and homogeneity

– level: low – moderate – high mean value

–homogeneity: variation coefficient (VC)

• In different nucleus farms

• In different nucleus companies

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Materials and methods

• PCV2 ELISA test

– SERELISA® PCV2 Ab (Synbiotics)

–Reproductibility

• 30% of variation: «normal» for the test (L. Mieli, LDA22, Pers. Comm.)

• Variation coefficient from PCV2 gilt Ab titers

– CV ≤ 30 % => within the intrinsic variability of the test

– CV > 30 % => means a biologically significant difference

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Materials and methods

• 30 nucleus farms

• Supplying 4 large French pig companies

–25% of French pigs produced

• No PCV2 vaccination on gilts

• 5 gilts/farm sampled per sampling session

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Materials and methods

• SERELISA® PCV2 Ab (Synbiotics)

• Thresholds for the mean Ab levels:

Low Moderate High

≤ 3.2 3.2< <4.0 > 4.0

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Results

• All companies

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% of Nucleus farms by category

Results

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Discussion, conclusion

• Wide variety of average titers, meaning different exposure to PCV2 antigen during the growth period: – among companies

– among gilts in the same company

• Need to improve and homogenize gilt immune status against PCV2 before they face exposure by the commercial sows -> vaccination in quarantine

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An example from the field

• Materials and methods – farrowing farm expanded from 450 to

800 sows

–150-gilt delivery every 6 weeks originating from a single source

– samples in three consecutive batches (10 gilts)

–gilts raised in a remote site

– reproductive performance individually recorded

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An example from the field

• Results prior vaccination

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An example from the field

• Variations in mean batch titres

– moderate to high

– VC higher in batches with low mean titres

Decision made

to vaccinate gilts at arrival:

CIRCOVAC® 2 x 2ml, IM, 3 weeks apart

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An example from the field

• Effect of vaccination on the Ab titres

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An example from the field: reproduction performance

• Fecundation rate

– 94 %

• Farrowing

– still-born: 9.4 % per sow

–mummies: 2.4 % per sow

–weaned: 11.7 piglets per sow

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Conclusion

• PCV2 immunity in gilts is highly variable and unpredictable

• High and homogeneous titers are beneficial

• CIRCOVAC vaccination in gilts is strongly recommended

–2 x 2 ml in quarantine

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Thanks for your attention!

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4TH MERIAL FORUM

HAVE WE GOT PCVD &

SWINE INFLUENZA UNDER

CONTROL?

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