1,200 bytes removed ,  18:50, 24 August 2010
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sufficient supervision should be given at lambing time to ensure adequate intakes of colostrium and the maintenance of good hygiene.
 
sufficient supervision should be given at lambing time to ensure adequate intakes of colostrium and the maintenance of good hygiene.
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Lamb dysentery can be controlled through vaccination against clostridial diseases. Before ewes enter the breeding flock, they should be given two vaccinations separated by an interval of 4-6 weeks. An annual booster should be given about six weeks before lambing to afford passive protection to lambs until around sixteen weeks of age. Lambs born to unvaccinated ewes should themselves be vaccinated at between 3 and 12 weeks old, with a second injection given at least four weeks later. Good husbandry is also critical to the control of lamb dysentery.
+
Lamb dysentery can be controlled through vaccination against clostridial diseases. Before the advent of modern vaccines,
Before the advent of modern vaccines,
   
losses from clostridial diseases could
 
losses from clostridial diseases could
 
be cata-strophic, on occasion running
 
be cata-strophic, on occasion running
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wanes over a period of a year and,
 
wanes over a period of a year and,
 
consequently, booster doses are
 
consequently, booster doses are
required annually.
+
required annually.Before ewes enter the breeding flock, they should be given two vaccinations separated by an interval of 4-6 weeks. An annual booster should be given about six weeks before lambing to afford passive protection to lambs until around sixteen weeks of age. Lambs born to unvaccinated ewes should themselves be vaccinated at between 3 and 12 weeks old, with a second injection given at least four weeks later. Good husbandry is also critical to the control of lamb dysentery.
* EWES. Vaccination should be performed
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four to six weeks before lambing
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is due. Where lambing is prolonged,
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the late lambers should be
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identified and boosted later, closer to
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their lambing date.
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* LAMBS. By virtue of the ewe's
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enhanced ability to concentrate circulating
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antibodies into the colostrum
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(Cooper 1967), lambs ingesting sufficient
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colostrum from adequately fed
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ewes receive sufficient maternal antitoxins
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to protect them for about 12
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weeks. Such maternal protection is
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essential to prevent lamb dysentery,
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tetanus and early enterotoxaemia
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caused by C perfringens type D.
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Lambs from fully vaccinated ewes
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can start their primary course from
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eight weeks of age, as maternally
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derived antitoxin does not appear to
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interfere with the response to the vaccine.
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The choice and combination of
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antigens to be used depends on the
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ultimate fate of the lamb. Those to be
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retained for breeding require the full
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complement of antigens. Those for
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early slaughter may only require protection
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against pulpy kidney disease
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and tetanus, while lambs aimed at the
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store market or autumn finishing
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require a wider range of antigens to
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give additional protection against
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braxy, blackleg and malignant oedema.
      
==Links==
 
==Links==
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