Hi there and thanks for your question. Neutrophils are white blood cells that fight infection. Pus is a collection of dead neutrophils. So, usually when the neutrophil level is high it means that the body is fighting infection. However, there are other possibiltiies so we usually interpret the Neutrophil level together with the rest of the bloodwork. Some animals can have a slightly high level just because they are a little stressed about being at the vet's office.
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