LAST EDITED ON Feb-09-15 AT 03:10PM (MST)[p]As a DVM myself, who has horse breeders and deer breeders for clients I play deer too.
Yep, deer where I live rut about 3 weeks earlier than the deer almost due west of here about 60 miles. Why, because of the vegetation in the springtime. West of here is drier and the sprintime greenup is later: fawns born earlier are more likely to die from starvation. So there is genetic selection in those deer to respond to a later photoperiod than the ones where I live.
Just like some of the deer in the northern states rut not much later than the ones in Texas, because it correlates to when their specific area greens up in the spring and most fawns survive. There genetics is selected by fawn survival, but again, what specifically tells the does when to come in heat that first time? Photoperiod
And what triggers the bucks to lose their velvet? Again, genetics that have been selected for the optimal breeding period. But what triggers the actual hormonal change that results in the buck shedding velvet? What tells that specific buck what day to change his hormones and start shedding velvet on? Photoperiod.
Yep, an individual doe can cycle at any time of the year, and once a buck sheds his velvet, he is ready to breed. In fact that is the only time he will be fertile. And even though he is ready in September, the rut usually doesn't happen until the photoperiod tells the does in his area to come in heat a few months after most bucks shed. But like most males, he is ready and waiting for those few that come in a little early!
txhunter58
venor, ergo sum (I hunt, therefore I am)