One of the best sources for information on Veterinary uniforms and insignia is Randy Steffen’s series of books titled The Horse soldier 1776-1943. There is too much information to post it all here. The books are available in most good libraries. If your local library does not have then you can often have them sent from a library that does.
In general the first uniforms for veterinrains were prescribed in 1901. They dressed like 2nd Lieutenants, of the cavalry or artillery depending on which they were attached to but without shoulder straps. In 1916 they were to wear uniforms like medical officers but with a VC on the caduceus. At some time the VC was changed to a V.
Did you want animal protective mask worn by U.S. or any army? I will have to give animal protective masks some thought, I know I have seen information but am not sure where.
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