Seasonal Mineral Needs

   I am occasionally asked what minerals for livestock are required at different times of the year — for example, “Going into winter, what minerals should I make sure are available for my livestock?”

   It is true that mineral consumption may vary with the season, under different circumstances, and even in different areas of the country. You may see other consumption patterns on your own farm, but here are some examples. 

  • When cattle are grazing on lush, fast growing spring grass   they will generally eat more Magnesium. 
  • Young stock seem to eat more Copper as do animals having to eat  moldy feed.  
  • Sulfur is involved in hair and hoof growth, When animals shed their winter coat and grow a summer coat they will eat more sulfur.  The same is true in the fall when they are growing a winter hair coat. 
  • Calcium consumption may go down in summer and up in winter.  I have no explanation for this, but I suspect it has to do with a seasonal variation in phosphorus availability.  
  • Animals will often drastically alter their mineral consumption within one day of ration changes.
  • Animals will sometimes take more minerals in advance of imminent weather changes.  It seems they anticipate feed may be limited during a storm and stock up on minerals to tide them over.   Bison appear to be especially canny in this regard.
  • If the water is high in nitrates, animals will need more need more Vitamin A. They will take more Vitamin A and B when forage quality in stored feed declines. 
  • Animals under stress for any reason will eat more Vitamin B..
  • If well nourished animals are are changed to a mineral deficient ration it may take several months for them to deplete their body reserves and begin to show deficiency symptoms.  When they are again supplied with adequate minerals, it may take several months for them to eat what is required to replenish these  reserves — refilling the tank.

   I don’t think it’s possible to accurately predict what minerals animals will need under varying circumstances.  Thus, it is important to provide a full array of minerals at all times and let the animal’s innate nutritional wisdom make that decision. 

   In the last analysis, there is only one answer to the question, “What is the most important mineral to have available for your animals?” — and the answer is, “The one that’s most deficient.”