ased nutrient requirements. In the case of bucks, this occurs at two different times of the year. The first period is the post-rut (January-March) when bucks are reeling from the rigors of the rut and trying to recover the 25-35% of body weight they lost while chasing does. Previous telemetry research through Texas A&M University-Kingsville indicates that nearly 80% of all buck mortalities occur during the post-rut. Obviously, the post-rut period is a very stressful time for bucks. The second period of physiological stress for bucks occurs when they are growing antlers (March-August). If your goal is to maximize antler growth, then as a minimum, you should provide supplementation during January-August.
The most physiologically stressful time for does occurs when they are pregnant (January-July) and later when they are nursing fawns (July-September). If one of your goals is to increase fawn production and survival, than supplementation should be continued through September.
It also takes time to get deer used to eating supplemental feed, especially the first year that the feeding program is initiated. If managers are not feeding on a year-round basis, they should begin supplemental feeding at least several weeks before the period they wish to cover with supplementation. In order to cover all of the different critical months for deer of both sexes, as a minimum, supplementation should be provided from December through September.
If a rancher or manager cannot afford to provide supplement year-round, than the “best” time not to provide supplemental feed is probably during late September through early December. The pre-rut and rut are possible times to stop supplementation because bucks at this time of the year greatly reduce feed intake in their endless pursuit of does. In fact, penned studies have shown that even when bucks are individually isolated in small pens, they will still voluntarily restrain from eating feed that is placed into their pen during the rut!
Look for part three of this six-part series on supplemental feeding next week. Part III will address the advantages and disadvantages of the most commonly used forms of supplemental feed for deer.
Posted by Dr. Mickey W. Hellickson