Presentation on theme: "PRRSV control and eradication in Spanish farms Enric Marco marco i collell; S.L."— Presentation transcript:
PRRSV control and eradication in Spanish farms Enric Marco marco i collell; S.L.
PRRS is possible Test and removal (Dee and Molitor, 1998), Closed up of the herd (Torremorell and Christianson, 2001) Partial depopulation (Plomgaard, 2001)
Critical points Persistence of the virus (Zimmerman, et al., 1992) 152 days in tonsils of infected animals (Wills, et al. 1997) 92 days in semen (Christopher-Hennings et al., 1995, Swenson et al. 1994) Viremic piglets can shed virus up to 7-16 weeks (Benfield et al., 1996)
Case 1: PRRS eradication in a small farrow to finish herd
The farm Year 2,000 230 sows farm Farrow to finish herd. Batch farrowing every 15 days. Finishing capacity: 50% Sows: LD x LW Boars: Pietrain-Halothane (-) (I.A.)
Eradication plan Switzerland eradicate M. hyo from small herds (Zimmerman, 1996). Denmark, the same methods are apply in larger herds (Plomgaard, J. 1998)
BASES: No animals present younger than 10 month of age. No replacement during 6 months. Nursery and finishing depopulation. Stop farrowing or move them to other facilities. Medicate the remaining stock Eradication plan
Medication all remaining animals: 5 injections of enrofloxacin (2,5 mg/Kg. BW) on days 1, 4, 8, 11 and 14. 2 injections of Doramectin (3 mg./Kg. BW) 14 days apart. Good cleaning and disinfection of empty rooms. Eradication plan
Sows wean outside farm were located in isolation during 15 days Where received Enrofloxacin and Doramectin. A.I. during this period. Remodelling took place during the eradication time. Eradication plan
Results No clinical signs of mange observe till now. No mange control is done. No lesions, no clinical signs of App observed till now.
Results M.hyo is still present on the farm. Replacement come from a positive source. Farm produced PRRS negative stock until December 2001 when became reinfected.
Case 2: PRRS eradication in a small farrow to finish Boar multiplier by total depopulation
The farm Year : 2,002 300 sows farm Farrow to finish herd. Boar multiplier Batch farrowing every week. Finishing capacity: 50% (boars and replacement) Sows: LW and (LW x Pt) IA in the farm: 5 boars: Pietrain
The farm –health status Mycoplasma hyopneumoniae PRRS infected in August 2001
BASES: Stop positive replacement during 6 months. Nursery and finishing depopulation. Eradication plan
Farm lay out 500 m. Gestation Farrowing room Nurseries Finishing barns Poultry barns
Eradication starts. January 2002 500 m. Gestation Farrowing room Nurseries Finishing barns Poultry barns Last PRRS negative replacement moved in
Eradication: March 2002 500 m. Gestation Farrowing room Nurseries Finishing barns Poultry barns Last Replacement PRRS (+) At 3 weeks piglets are weaned outside Replacement of all AI boars by PRRS (-)
Eradication: September 2002 500 m. Gestation Farrowing room Nurseries Finishing barns Poultry barns Piglets are weaned again inside
Eradication: October 2002 500 m. Gestation Farrowing room Nurseries Finishing barns Poultry barns NEW PRRS negative replacement moved in
Eradication: December 2002 500 m. Gestation Farrowing room Nurseries Finishing barns Poultry barns All samples Show PRRS negative results
Eradication: January 2003 500 m. Gestation Farrowing room Nurseries Finishing barns Poultry barns PRRS (+)
Eradication continues January 2004: same process is done again October 2004: Positive animals in Finishing again EXTERNAL FINISHING HAS NOT BEEN EMPTIED
Eradication continues January 2005: TOTAL DEPOPULATION May last PRRS (+) sows farrow July 2005 first sows farrow To accelerate the program matings has been done out side. New stock: PRRS negative M. hyo negative
The farm –health status Mycoplasma hyopneumoniae PRRS
Farm lay out > 10 Km. Gestation Farrowing room Nurseries Finishing barns: Own replacement SITE 1 SITE 2 EXTERNAL SITE 3 > 1000 Km.
Future farm lay out > 10 Km. Gestation Farrowing room Nurseries Finishing barns: Own replacement and gilts to sale SITE 1 SITE 2 SITE 3 3 Km. 800 m.
BASES: Stop positive replacement during 6 months. Nursery and finishing depopulation. Using the possibility of new facilities. Eradication plan
Eradication Plan March 2003: Last replacement PRRS (-) June 2003: Last replacement show titers to PRRS June 2003: Inside nurseries emptied July 2003: 4 weeks after, weaned pigs moved to new sites 3 (wean to finish) Own replacement and few more to fill up barns.
Eradication Plan July 2003: inside nurseries emptied October 2003: Inside Finishing barn emptied November 2003: New PRRS replacement located in new inside finishing barn. Managed independently. November 2003 old inside finishing remodeled to gestation December 2003: Elimination of any gilt or sow PRRS (+) not mated. Stop using PRRS (+) boars
Eradication Plan February 2004: Replacement in new site 3 negative to PRRS is moved to site I. March 2004: last farrowings from PRRS (+) sows April 2004: first farrowing from new PRRS (-) gilts. April 2004: weaners moved to new Site 2. April 2004: Old site 2 is emptied.
Results Up today all analysis have shown negative results form all sites.
Production gaps Form last replacement negative to become positive: 3 m. From last replacement negative to first weaners (future replacement on external site) that remain on farm: 4 m. From last replacement once positive to new replacement negative: 5 m.
Case 4: PRRS eradication in a 3 sites herd without partial depopulation
The farm Year: 2,006 800 commercial farm 3 sites herd. Farrowing every second week. Sows: Ld x Lw AI boar stud in farm 4 Boars: Pietrain Own replacement GPs external source
History 400 sows close herd 1992 PRRS infection 1998 control PRRS Own-replacement Gps + F1 acclimatization (contact with viremic pigs) 2002 Change to 3 sites system Increase population from 400 sows to 750 2006 PRRS circulating on site 2 + 3 No circulation on sow herd
The farm –health status Mycoplasma hyopneumoniae PRRS
BASES: Stop positive replacement during 1 month. No nursery depopulation Eradication plan
Eradication Plan 1.Stop recirculation on site 2 (8-9 weeks of age) Increase Biosecurity among batches Different boots per barn Specific material per barn (syringes, medicines, etc) 2.Once recirculation on site 2 stops (week 0) Stop introduction of F1 on site 1 (once first batch is detected negative) one month (two consecutives batches). Move negative F1 from site 2 to isolated external finishing and keep them isolated. (week 2)
Eradication Plan 3.Control PRRS status on site 2 (week 12) 4.Control PRRS status last replacement PRRS positive still on farm by PCR (week 16). If PCR negative Move negative F1 to site 1 (week 20) Breed negative F1 (week 26) Keep them isolated from the rest of the sows util gestation is confirmed (4 weeks) 5.Week 30: Herd come back to normality
Results Farm has been PRRS negative up to January 2012
Production gaps From last replacement positive to new replacement negative: 1 m. But new replacement kept in isolation during 6 months.
Conclusions PRRS elimination is possible, but not always easy. People on farm have to be involved on the project. Replacement and weaners are critical areas for PRRS control. Good location and biosecurity are essential to maintain PRRS free status.