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| | ==Treatment and Control== | | ==Treatment and Control== |
| − | dos: Control of enterotoxaemia involves reducing factors that can precipitate disease. Diets should not be changed suddenly and, when feeding conentrates, a slow introduction is essential. If cereals are fed, then whole grain should be used to prevent too rapid passage from the rumen to the bomasum and jejunum. Because ''C.. perfringens'' type D is ubiquitous in its distribution, control measures will only reduce but not prevent disease. As with all the other enterotoxaemis, the disease is best prevented by vaccination.
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| − | Presentation of lamb dysentery is usually peracute, with sudden deaths occuring before treatment can be implemented. Even if animals are found prior to death, treatment is usually unrewarding as organs are irreversibly damaged by toxins by the time signs present<sup>2</sup>. Instead, a definitive diagnosis should be pursued before greater losses occur, and the farmer should be encouraged to submit the carcase for further investigations.
| + | The first sign of pulpy kidney is sudden death, and so there is often no opportunity for treatment. Even if affected animals are found prior to death, treatment is usually unrewarding as organs are irreversibly damaged by toxins by the time signs present<sup>2</sup>. Instead, a definitive diagnosis should be pursued before greater losses occur, and the farmer should be encouraged to submit the carcase for further investigations. |
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| − | As treatment is so ineffective, much emphasis is put on to the control of lamb dysentery. Vaccination in the face of an outbreak has been shown to be effective<sup>7</sup>, and specific hyperimmune serum can also be administered<sup>4, 6t</sup>. Oral antibiotics may be given<sup>4</sup> but are regarded as a less appropriate therepautic. Management measures such as removing the flock from a particular pasture or reducing concentrate feeding may be implemented in other clostridial diseases but are of no benefit in lamb dysentery: over-ingestion of the dam's milk combined with poor hygiene are responsible for this disease. Therefore,
| + | Control of pulpy kidney involves avoiding the fators that can precipitate disease. Diets should not be changed suddenly and concentrate feeding should always be introduced slowly<sup>dos</sup>. Feeding of whole grain slows the transit of feed to the small intestine, so cereals should be fed in this form. ''C.. perfringens'' type D is ubiquitously distributed and so management measure will never completely prevent disease. The best method of disease prevention is vaccination. |
| − | 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 the development of modern clostridial vaccines in the 1970s, catastrophic losses of up to 30% of the lamb crop could occur due to lamb dysentery<sup>2</sup>. The vaccines used today are effective against a variety of clostridial diseases and some vaccines are combined for effects against ''Pasteurella''. The vaccines consist of toxoids which are inactivated forms of the toxins produced by clostridial organisms. The principles of vaccination are the same whether a clostridium-only or ''Pasteurella''-combined product is used: a sensitising dose must be given 4-6 weeks before a second, confirming dose<sup>2</sup>. As immunity wanes over a period of a year booster doses are required annually. Therefore, ewes should receive the primary vaccination course before entering the breeding flock and an annual booster approximately six weeks before lambing. Timing the booster vaccination in this way affords passive protection to lambs until they are around sixteen weeks of age. Lambs born to unvaccinated ewes should be vaccinated between 3 and 12 weeks old, with a second injection given at least four weeks later.
| + | Before the development of modern clostridial vaccines in the 1970s, losses of up to 15% of the lamb crop could occur due to pulpy kidney<sup>2</sup>. The vaccines used today are effective against a variety of clostridial diseases and some vaccines are combined for effects against ''Pasteurella''. The vaccines consist of toxoids which are inactivated forms of the toxins produced by clostridial organisms. The principles of vaccination are the same whether a clostridium-only or ''Pasteurella''-combined product is used: a sensitising dose must be given 4-6 weeks before a second, confirming dose<sup>2</sup>. As immunity wanes over a period of a year, booster doses are required annually. Therefore, ewes should receive the primary vaccination course before entering the breeding flock and an annual booster approximately six weeks before lambing. Timing the booster vaccination in this way affords passive protection to lambs until they are around 16 weeks of age. Lambs born to unvaccinated ewes should be vaccinated between 3 and 12 weeks old, with a second injection given at least four weeks later. |
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| | ==Links== | | ==Links== |