The first step: How should diagnosis be performed correctly?
The appearance of clinical signs may indicate that there is a problem, but we should not rely on them alone. Laura’s recommendation is to always perform a laboratory diagnosis to detect the pathogen.
Laboratory confirmation of the pathogen is crucial
There are several techniques; the most recommended is PCR, which allows us to confirm the presence of Chlamydia. Serology can also be performed, giving us information about circulation within the flock.
Steps for proper sampling:
– Identify abortions
– Collect the placentas. If these are not available, collect the fetuses
– If neither is available, take a vaginal swab from animals suspected of having aborted.
– If we can only perform serology, it should preferably be done on recently aborted animals, because antibody levels increase.
Proper sampling is essential for obtaining an accurate diagnosis.
Let us imagine we are facing an outbreak—what should we do?
For Laura, the first thing is to implement biosecurity measures.
The placentas and fetuses must be quickly removed and then incinerated or buried. Afterwards, disinfect the area and isolate the affected animals.
In addition, send the samples mentioned above.
And what if we receive a positive diagnosis?
We must reinforce these biosecurity measures, especially to protect healthy replacement animals. At this point, vaccination is crucial; the flock’s immunity must be increased.
Ideally, the whole flock should be vaccinated so that it is protected.
Vaccination is important for reducing the number of abortions, but also for reducing shedding, which, as we saw, is the key point in controlling the disease.
In the field, there are doubts about the use of antibiotics. What can you tell us about this issue?
In cases of outbreak, they help reduce the number of abortions because they reduce multiplication of the bacteria in the placenta.
However, this treatment is limited and is only useful for a short period of time.
Antibiotics do not eliminate the infection; the animals will remain infected and may abort the following year.
In addition, we must take into account the risk of antimicrobial resistance, which is a global health problem.
Vaccines have been available on the market for years. Why do problems persist?
Chlamydia may be hidden in the flock; in other words, animals may be infected and show no signs.
In addition, because it is an intracellular pathogen, the immune response varies from one animal to another. For this reason, it is important to follow the vaccination protocol correctly.
Vaccination must be combined with biosecurity measures
Which farms should consider vaccination?
The disease is endemic, so all farms are at risk of infection.
In some cases, for example if animals are purchased or grazing is shared, it is always advisable to consider vaccination.
Article written by:
Tania Perálvarez Puerta. Global Product Manager, HIPRA.
