I shot this guy a couple years back.  In velvet in Mid October.  All of his anatomy was accounted for.  He had a huge body with over an inch and a half of body fat on the top of his back.  Very tasty deer.
I'll second that.  I killed one very similar about 15 years ago, was absolutely fantastic eats.  Like comparing a steer to a bull.  Mine had under-developed testicles, about 3/4".
In addition to trauma, it is not uncommon to see this in mule deer (testicular atrophy) as a result of hydrocarbon environmental contamination.  In eastern Wyoming, there were a couple of old refineries and oil fields where they were fairly common.  The effect was first discovered in HUMAN oil field and refinery workers  

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