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Bird autopsy: How to spot trichomonosis disease

A disease that is killing greenfinches and chaffinches in the UK has now spread to Europe, scientists report.

A paper in the journal Ecohealth confirms that the disease has been found in Finland, Norway and Sweden and is at risk of moving further afield.

The disease, called trichomonosis, is caused by a parasite and was first seen in finches in the UK in 2005. Since then, the country's greenfinches have declined by 35% and chaffinch populations have fallen by 7%.

Here, Becki Lawson, a wildlife veterinarian at the Zoological Society for London (ZSL), has been performing post mortems on greenfinches to try to find out more about trichomonosis.

Here, during one of the procedures, she reveals the external and internal signs of the deadly disease.