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Managing control programs for ovine caseous lymphadenitis and paratuberculosis in Australia, and the need for persistent vaccination

Ovine caseous lymphadenitis (CLA) and ovine Johne’s disease (OJD) or paratuberculosis have been serious diseases in the Australian sheep industry, mainly causing losses from abattoir condemnations from CLA or mortalities on the farm from OJD. CLA is now a disease of minimal concern, with clinical ca...

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Autor principal: Windsor, Peter Andrew
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Dove 2014
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7337174/
https://www.ncbi.nlm.nih.gov/pubmed/32670842
http://dx.doi.org/10.2147/VMRR.S44814
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author Windsor, Peter Andrew
author_facet Windsor, Peter Andrew
author_sort Windsor, Peter Andrew
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description Ovine caseous lymphadenitis (CLA) and ovine Johne’s disease (OJD) or paratuberculosis have been serious diseases in the Australian sheep industry, mainly causing losses from abattoir condemnations from CLA or mortalities on the farm from OJD. CLA is now a disease of minimal concern, with clinical cases reported rarely. Although OJD continues to spread through parts of the sheep population, the catastrophic losses in flocks occurring prior to the introduction of vaccination are now uncommon. Change-management factors relevant to the improvements in both prevalence and producer concerns for CLA and OJD were examined, including drivers and motivation for change, resistance to change, knowledge management, farming system dimensions and leadership. Although extension programs addressing disease risk factors are likely to be of relevance to improved knowledge and attitudes towards disease risk management of producers, improvements in disease-control practices were considered largely attributable to the introduction of vaccination programs for CLA in 1983 and OJD in 2002. Inclusion of the CLA antigen within clostridial vaccines (“6 in 1” vaccine) enabled routine annual CLA vaccination to occur in an increasing proportion of the national flock, with estimates of CLA prevalence suggesting a decline from 26% in 1995 to 5.2% in 2009. Encouraging the routine vaccination of lambs for OJD (Gudair vaccine) in infected flocks to reduce or avoid losses significantly reduced the within-flock prevaccination–postvaccination median prevalence from 2.72% to 0.72%, based on estimated shedding rates of Mycobacterium avium subsp. paratuberculosis determined by pooled fecal culture in 37 infected flocks vaccinating for at least 5 years. Although persistent use of CLA vaccine is a convenient intervention for producers, promoting the persistent use of OJD vaccination to continue disease suppression when clinical cases are undetectable, plus improvements in biosecurity, remain a challenge for animal-health authorities. Despite concerns of vaccine efficacy and safety issues with OJD vaccination, persistent vaccination has produced a profound improvement in the health of Australian sheep, and is a positive development of relevance to sheep production in other countries.
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spelling pubmed-73371742020-07-14 Managing control programs for ovine caseous lymphadenitis and paratuberculosis in Australia, and the need for persistent vaccination Windsor, Peter Andrew Vet Med (Auckl) Review Ovine caseous lymphadenitis (CLA) and ovine Johne’s disease (OJD) or paratuberculosis have been serious diseases in the Australian sheep industry, mainly causing losses from abattoir condemnations from CLA or mortalities on the farm from OJD. CLA is now a disease of minimal concern, with clinical cases reported rarely. Although OJD continues to spread through parts of the sheep population, the catastrophic losses in flocks occurring prior to the introduction of vaccination are now uncommon. Change-management factors relevant to the improvements in both prevalence and producer concerns for CLA and OJD were examined, including drivers and motivation for change, resistance to change, knowledge management, farming system dimensions and leadership. Although extension programs addressing disease risk factors are likely to be of relevance to improved knowledge and attitudes towards disease risk management of producers, improvements in disease-control practices were considered largely attributable to the introduction of vaccination programs for CLA in 1983 and OJD in 2002. Inclusion of the CLA antigen within clostridial vaccines (“6 in 1” vaccine) enabled routine annual CLA vaccination to occur in an increasing proportion of the national flock, with estimates of CLA prevalence suggesting a decline from 26% in 1995 to 5.2% in 2009. Encouraging the routine vaccination of lambs for OJD (Gudair vaccine) in infected flocks to reduce or avoid losses significantly reduced the within-flock prevaccination–postvaccination median prevalence from 2.72% to 0.72%, based on estimated shedding rates of Mycobacterium avium subsp. paratuberculosis determined by pooled fecal culture in 37 infected flocks vaccinating for at least 5 years. Although persistent use of CLA vaccine is a convenient intervention for producers, promoting the persistent use of OJD vaccination to continue disease suppression when clinical cases are undetectable, plus improvements in biosecurity, remain a challenge for animal-health authorities. Despite concerns of vaccine efficacy and safety issues with OJD vaccination, persistent vaccination has produced a profound improvement in the health of Australian sheep, and is a positive development of relevance to sheep production in other countries. Dove 2014-03-24 /pmc/articles/PMC7337174/ /pubmed/32670842 http://dx.doi.org/10.2147/VMRR.S44814 Text en © 2014 Windsor http://creativecommons.org/licenses/by-nc/3.0/ This work is published by Dove Medical Press Limited, and licensed under Creative Commons Attribution – Non Commercial (unported, v3.0) License. The full terms of the License are available at http://creativecommons.org/licenses/by-nc/3.0/. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. Permissions beyond the scope of the License are administered by Dove Medical Press Limited. Information on how to request permission may be found at: http://www.dovepress.com/permissions.php
spellingShingle Review
Windsor, Peter Andrew
Managing control programs for ovine caseous lymphadenitis and paratuberculosis in Australia, and the need for persistent vaccination
title Managing control programs for ovine caseous lymphadenitis and paratuberculosis in Australia, and the need for persistent vaccination
title_full Managing control programs for ovine caseous lymphadenitis and paratuberculosis in Australia, and the need for persistent vaccination
title_fullStr Managing control programs for ovine caseous lymphadenitis and paratuberculosis in Australia, and the need for persistent vaccination
title_full_unstemmed Managing control programs for ovine caseous lymphadenitis and paratuberculosis in Australia, and the need for persistent vaccination
title_short Managing control programs for ovine caseous lymphadenitis and paratuberculosis in Australia, and the need for persistent vaccination
title_sort managing control programs for ovine caseous lymphadenitis and paratuberculosis in australia, and the need for persistent vaccination
topic Review
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7337174/
https://www.ncbi.nlm.nih.gov/pubmed/32670842
http://dx.doi.org/10.2147/VMRR.S44814
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