The local animal control people can advise you. Also, the local shooting range/hunting club can lawfully process an injured game animal.
WRC doesn't rescue deer. They might have a resource to recommend.
Check for a number for bistate wildlife hotline.
Injured deer, most likely shoot it, put out of misery, agree chech with conservation first,
Typically the Wildlife Rescue Center does not handle deer. Try the Missouri Dept of Conservation.
Wildlife rescue center in Ballwin Missouri could possibly help.
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