In order to enter an animal as DOA, you'll need to configure an intake subtype, under the specific intake type you'd like to use, that is set to Live Intake = DOA (see below).
Any animal that is intaken with a subtype configured as "DOA" will automatically be outcomed for you upon intake. These outcomes will always be included on the "Custom Events Outcomes Not Counting Towards Live Outcome" Report: 
Due to this, in order to prevent a mis-match of events from occurring, you will want to be sure that any intake subtypes configured as "DOA" are also configured to "No" in the Count towards Intake Numbers configuration.
See these articles here for more information on setting up intake and outcome subtypes: Setting up your intake forms and subtypes and Setting up your outcome forms and subtypes.
Additionally, this article offers additional information on editing your subtype configurations: How do I edit an intake or outcome subtype?