Based off my experience over the last 17 years of being in the business, and being able to travel to ranches all across the state it seems whitetails peak at 6/7 years of age depending on the genetic line. The northern strain genetics seem to top out a tad earlier than the South TX lines from what I've seen. On almost all of the other exotics mentioned 5-6 years of age seems to be the norm. I have seen both whitetails and axis continue to improve at 9+ years of age. Granted those jumps are far less than the "prime years", but still a gain. Like the Rancher and Don mentioned the risk vs. benefits for ranches to let these animals fully mature these days just isn't worth it. It's far more profitable to shoot them at 3-5. Overhead to run a ranch is far more than what hunters think.
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