2% or less is considered to be the “normal” abortion rate but it’s not sensible to wait until 2% of cows have aborted before collecting samples for investigation. Some guidelines for deciding when to investigate can be found on page 2. In cattle there are valid reasons for investigating every abortion particularly if you are breeding your own replacements. You do not want to maintain BVD or Neospora infection in the herd. Cows infected with Neospora may abort again and any heifer calves that are retained could abort during their first pregnancy. Investigating all abortions can help with planning culling decisions and breeding strategies.
Consider investigating if:
- There have been 2 or more abortions in a short space of time.
- Abortions are occurring in a specific group of animals e.g. purchased replacements, animals in their first pregnancy.
- There is a need to check a vaccine is working.
- Problems were seen in 2016 and either not investigated or no diagnosis was reached.
- Aborting cattle are ill, scouring or dying.
Working out the cause can help to:
- Plan future vaccination programmes.
- Highlight a risk to other livestock species.
- Highlight a problem with feed.
- Highlight a risk to human health.
If distance and time is not a problem deliver aborted lambs plus placentas to your local veterinary laboratory. Lambs and placentas from different ewes should be placed in separate bags. Otherwise your vet can collect samples to post for testing.
Heather Stevenson, email@example.com
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