Like most things, moderation is the key to using cottonseed as deer feed.
QUESTION: Do you know of studies you can direct me to that show cottonseed does not impact the fertility of whitetail bucks?
ANSWER: Not exactly, but I can provide some information on the use of cottonseed as an attractant or supplemental deer feed. It’s high in crude protein (23%), does not easily degrade under moist conditions, is readily available and less expensive (about half the cost of formulated protein pellets), and non-target species like hogs and raccoons don’t eat it (making it even less costly).
However, there are some risks associated with providing it. Deer have a very complex digestive system, and the sudden presence or absence of a particular type of food can affect the rumen bacteria, reducing a deer’s ability to digest any food. If you provide supplemental feed, especially things like corn and cottonseed, you should begin and end gradually so the deer’s digestive system can adjust.
Furthermore, cottonseed contains a chemical called gossypol that can have detrimental effects on deer. According to research by Charles DeYoung at the Caesar Kleberg Wildlife Research Institute, Texas A&M University-Kingsville, “... male domestic ruminants fed high concentrations of cottonseed for extended periods have decreased reproductive ability.”
There are several ways to reduce potentially harmful effects. One is simply reducing the amount, and therefore the concentration, of cottonseed you provide. Another is limiting the time you provide it. DeYoung noted a common pattern is to feed from January 1st until spring green-up. “Deer will usually quit eating the feed anyway in the early spring,” he wrote. Feed again once the weather turns hot, then taper off around the time bucks shed velvet. Gossypol will leave a deer’s system when feeding ceases and fertility will return if it has been reduced.
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