High level of nitrates have been detected in forages this year in South Dakota and other states. Depending on where you live, it could be due to weather conditions, fertilizer, previous crop, or a combination.
Glenn Obermann has a winning recipe for quality hay. At the 2018 Missouri State Fair, Obermann took Champion and Reserve Champion awards in alfalfa and grass classes 4-8, and Champion in alfalfa classes 1-3.
Even with the high cost of vitamin A right now due to a global vitamin shortage, the extremely high cost of lost production from lack of vitamin A makes continued supplementation during winter months still important.