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Guide to fish health

We're delighted to have teamed up with fish health experts at the Environment Agency to bring you this series of articles on fish health.

A scientist with an infected salmon

Identifying diseases

Each of the articles in this series will explore a specific fish disease in detail, showing how it can be identified and offering guidance as to what action, if any, an angler would need to take if they encountered the particular disease.

Argulus (fish louse)

A highly damaging parasite and one of the greatest threats to stillwater trout fisheries

Carp Edema Virus (CEV)

CEV causes serious disease in common carp

Koi Herpesvirus (KHV)

KHV is a virus that infects common carp (Cyprinus carpio) and its ornamental varieties, such as koi and ghost carp

Saprolegnia in wild salmonoids

A fungal-like organism that infects freshwater fish and their eggs

How to tell the age of a fish

Did you know that fish can be aged?

Last Edited: 11 September 2023

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