I found out about it last year at the TAMU Experiment Station in Sonora. Iknewpeople had been feeding cottonseed to cattle for years, butit had never crossed my mind that deermightbenefit from it. Cottonseed is relatively cheap, but it isn't quite as cheap as corn. But it has a lot higher protein content. Many of my cattle protein supplements derive their protein from cottonseed meal. For a PVC feeder consumption is harder to control, and I can't remember exactly what they did in Sonora. Sorry I don't have that many specific answers to your questions. You might try contacting the Experiment Station.

http://agresearch.tamu.edu/CORD/SanAngelo.htm

http://www.findarticles.com/p/articles/mi_qa3826/is_200201/ai_n9020088

http://www.livestockweekly.com/papers/02/12/19/whlcottonseed.asp