PRRSV-Eradikation durch Einsatz einer Lebend - vakzine, partielle Depopulation und Modifizierung der Tierbewegungen (Pig Flow)

Zusammenfassung

Gegenstand und Ziel: Ziel dieser Untersuchung war die gezielte PRRSV-Eradikation in einem Herdbuchzuchtbetrieb in der Jungsauenaufzucht und Mast ohne Ausgliederung von PRRSV-positiven Tiergruppen auf einen anderen Produktionsstandort. Material und Methoden: Die Eliminierung erfolgte in mehreren Schritten: 1. Erhebung des PRRSV-Status der Herde mittels Real-Time-RT-PCR und ELISA sowie zweimalige Vakzination aller Tiere der Jungsauenaufzucht und Mast mit einer Lebendvakzine (Porcilis® PRRS-Lebendimpfstoff, Intervet GesmbH, Wien, Österreich) im Abstand von 21 Tagen. 2. Schließung der Jungsauenaufzucht und Mast für 60 Tage. 3. Teilweise Depopulation“ der Jungsauenaufzucht und Mast durch Modifizierung der Tierbewegungen ohne Entfernung/Ausgliederung auf einen anderen Standort. 4. Integration PRRSV-negativer Schweine und Koexistenz mit positiven Tieren ohne Neuinfektion. Ergebnisse: Die Produktion PRRSV-Anti - körper-(Ak-)negativer Jungsauen unter Koexistenz Ak-positiver Tiergruppen am gleichen Standort ohne Auslösung eines neuen Infektionsausbruches konnte über einen Zeitraum von zumindest 4 Monaten dokumentiert werden. Zu keinem Zeitpunkt der Untersuchung mussten PRRSV-positive Tiergruppen entfernt oder auf einen anderen Standort ausgegliedert werden. Schlussfolgerung: Durch gezielte Anwendung der Lebendvakzine und teilweise Depopulation ohne Entfernung PRRSV-positiver Tiergruppen vom Standort konnte eine PRRSV-Eradikation erreicht werden. Klinische Relevanz: PRRS ist eine der weltweit bedeutsamsten Krankheiten in der Schweineproduktion, wodurch der Prophylaxe, Bekämpfungsmaßnahmen sowie Sanierungs- und Eradi - kationsprogrammen große Bedeutung zukommt.

Summary

Objective: The aim of this study was the specific eradication of PRRSV in breeding gilts and fattening pigs in a breeding farm without the need for moving or transferring PRRSV positive pigs or transfer to an external production site. Material and methods: The eradication was carried out in four steps: 1. Investigation of the PRRSV status of the herd by real-time-RT-PCR and ELISA, as well as twofold vaccination of all breeding gilts and fattening pigs with an attenuated live vaccine (Porcilis® PRRS, Intervet, Vienna, Austria) with an interval of 21 days. 2. Herd closure of the sections breeding gilts and fattening pigs for a period of 60 days. 3. Partial depopulation of breeding gilts and fattening pigs through modified pig flow without removal of PRRSV positive pigs or transfer to an external production site. 4. Integration of PRRSV negative pigs coexisting with PRRSV positive pigs without triggering a re-infection. Results: The production of PRRSV antibody negative breeding gilts under coexistence of PRRSV positive pigs at the same production site without triggering a PRRSV reinfection was documented over a period of 4 months. It was not necessary to remove PRRSV positive pigs or transfer them to an external production site at any time during the whole study period. Conclusion: PRRSV eradication can be carried out successfully by usage of a live vaccine along with partial depopulation without removal or transfer of PRRSV positive pigs to an external production site. Clinical relevance: PRRS is one of the most important diseases in swine production worldwide, whereby the prevention, control measures as well as eradication programs are of great importance.

Schlüsselwörter

PRRSV-Eradikation - Schwein - partielle Depopulation - PRRSV-Lebendvakzine

Keywords

PRRSV eradication - pig - partial depopulation - PRRSV live vaccine

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