Epizootic
An outbreak or epidemic of disease in animal populations affecting many animals of one kind at the same time, e.g. avian flu in fowl, foot and mouth disease in cattle
Glossary Source
JRC EU CBRNe Glossary
(
EU Glossary on Chemical, Biological, Radiological, Nuclear, and Explosive risks
)
https://publications.jrc.ec.europa.eu/repository/bitstream/JRC128863/JRC128863_01.pdf