Ovine footrot – further investigations in preparation of a new Swiss nation wide footrot control program

• Unité de recherche: OSAV
• Numéro de projet: 1.16.03
• Titre du projet anglais: Ovine footrot – further investigations in preparation of a new Swiss nation wide footrot control program

Mots-clé (Allemand)

Schaf; Moderhinke; Lahmheit, Herdensanierung; Dichelobacter nodosus; AprV2-Protease; risikobasierte Überwachung

Mots-clé (Anglais)

Sheep; footrot; lameness; within herd control; Dichelobacter nodosus; AprV2-protease; risk-based surveillance

Description succincte (Allemand)

Moderhinke (MH) ist eine der wichtigsten Schafkrankheiten. Der politische, wirtschaftliche und soziale Druck, MH in der Schweiz flächendeckend zu bekämpfen, ohne dabei Antibiotika einzusetzen, ist in den letzten Jahren stark angestiegen. Die bisherige Bekämpfungsstrategie des BGK war nicht durchwegs erfolgreich, weil diese auf die Klinik der MH anstatt auf den Nachweis von virulenten D. nodosus abstützt. Von unserer Forschungsgruppe wurde ein neuer kompetitiver PCR entwickelt, welcher den Nachweis von virulenten D. nodosus (AprV2) ermöglicht. Die Motion Hassler verlangt, die Voraussetzungen zu schaffen, damit schweizweit eine koordinierte Bekämpfung der Moderhinke der Schafe durchgeführt werden kann. Das vorliegende Projekt soll wissenschaftliche Grundlagen für eine erfolgreiche MH-Bekämpfung in der Schweiz schaffen: A: Entwicklung einer neuartigen, risikobasierten Herdenüberwachung; B: Evaluation des Poolings von Proben mehrerer Schafe zur Senkung der Kosten und C: Untersuchung der Rolle von Ausstellungen und Klauenpflegeinstrumenten bei der Übertragung von MH.

Description succincte (Anglais)

Footrot is one of the most prevalent health problems in Swiss sheep flocks. Currently, the political, societal and economical pressure to sustainably control footrot nationwide without the use of antimicrobials is steadily increasing. As the control program offered by the BGK was not always successful, the strategy of Swiss footrot control is under critical review. It is taken into consideration to specifically control virulent D.nodosus, expressing the virulent protease AprV2 from sheep flocks nationwide, since (i) it is preferable for control programs to rely on attributes of D. nodosus rather than the clinical signs and (ii) a rapid diagnostic tool for detection of virulent D. nodosus is now available. The current project is proposed to elaborate further scientific evidence for a successful footrot control program. The objectives of the subprojects A-C are to evaluate A) a novel risk based footrot status control program, B) pooling of samples to reduce costs, and C) the potential of transmission of footrot at sheep shows and via inanimate vectors at trimming.

Objectifs du projet (Anglais)

The planned Swiss national footrot control program shall aim at a relevant reduction of sheep suffering from clinical signs of footrot nation wide. This should be achieved by a substantial reduction of the prevalence of the virulent, but not the benign strains of D. nodosus within the Swiss sheep population. The status “virulent” of a certain strain of D. nodosus will rely on the presence of the AprV2 gen. As shown in project (1.15.04), a complete within-herd eradication of virulent strains of D. nodosus is possible and practicable (Greber and Steiner, 2015). Therefore, the specific objectives of this study are:

• Objective of subproject A is to evaluate the clinical efficacy and sensitivity of a novel and simplified “risk based footrot status control program”, for replacement of the current fastidious “BGK-Frühjahrskontrolle”.

• Objective of subproject B is to evaluate the laboratory and clinical feasibility of using pooled samples (10 individual sheep samples pooled in 1 sample) in comparison with 10 individual samples for (i) the “new PCR-based within-herd eradication program” (Greber and Steiner, 2015) and (ii) the “risk based herd status control program”.

• Objective of subproject C is to evaluate the potential for transmission of virulent strains of footrot to previously AprV2-negative sheep during (i) sheep shows and (ii) foot trimming via foot trimming instruments (mainly hoof knives), clothing (shoes and gloves) of foot trimmers or horn material removed during gentle foot trimming. Furthermore, measures will be proposed to minimize the potential of transmission during the described events.

Not included in this study is the evaluation of alternative footbath solutions for within-herd eradication of virulent footrot. Currently, the Federal Office for the Environment FOEN is involved to provide an expert opinion on the potential risk for the environment (soil and ground water) by using Cu⁺⁺ and Zn⁺⁺ -based footbaths for control of footrot on a national basis.

 

Mise en oeuvre et application (Allemand)

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Documents annexés

• Steiner DB [PDF] 177 kB

Adresses URL (Allemand)

1.16.03 Steiner Moderhinke beim Schaf - Weitere Untersuchungen zur Vorbereitung eines neuen Schweiz…