As a result of vitamin A and E manufacturing problems, supplies of these vitamins are becoming scarce and prices of these vitamins have increased.  Expectations are that these production issues will continue for approximately the next 6 months.  Depending on individual company supplies and whether a farmer has forward contracted grain needs, grain and complete mineral mix prices will most likely reflect these shortages with an increased price.

Both Vitamin A and E are fat-soluble vitamins and need to be supplemented to dairy cattle.  Vitamin A is important for normal growth, prevention of night blindness, reproductive functions, and optimum immune response to decrease the incidence of diseases, such as mastitis.  Fresh forages contain more β-carotene, the precursor for Vitamin A, than stored forages.  Concentrations of β-carotene decrease quickly after forage harvest and as length of storage increases, concentrations decrease.  Thus, the need to supplement the diets of dairy cows, heifers and dry cows especially those fed stored forages and grain.

Vitamin E content of forages also is highly variable.  Like Vitamin A, the concentration of Vitamin E in forages decreases rapidly after cutting.  Forages stored as either hay or silage are lower in Vitamin E concentration than fresh forage and as length of storage time increases, concentrations of vitamin E decrease.  Adequate amounts of vitamin E are needed for proper immunity to help prevent the occurrence of mastitis and metritis and for reproduction in the prevention of retained placentas.  To prevent white muscle disease in calves, both adequate amounts of Vitamin E and selenium are needed.  Newborn calves rely on Vitamin E found in colostrum and then supplementation in milk based diets.  Vitamin E concentration in colostrum is related to vitamin E intake of their dam, thus illustrating the importance of nutrition of the dam on the newborn calf.

The good news in this discussion is that most nutritionists previously included at least twice the requirement for these vitamins in diets for dairy cattle.  This practice allows the feed industry to adjust the amounts fed without expecting an impact on performance.  For Vitamin A, the 2001 NRC (most recent published version) lists the requirement for heifers, dry cows and lactating cows of supplemental Vitamin A at 50 IU per pound of body weight or 75,000 IU supplemental Vitamin A for a 1500 lb Holstein. Recommendations for Vitamin E are 0.7 IU per pound of body weight for dry cows and 0.35 IU per pound of body weight for lactating cows.  These recommendations are approximately equal to 1000 IU of supplemental Vitamin E for dry cows and 500 IU for lactating cows.  Dr. Weiss, a vitamin researcher from The Ohio State, noted that the most critical time for use of supplemental Vitamins A and E is before freshening, thus the first priority should be in maintaining the optimum amount of these vitamins in the dry and prefresh diets.  Hopefully, the industry can effectively deal with these shortages until vitamin production can meet industry needs and prevent deficiencies in all livestock industries, not just dairy and beef.

Author:  Donna Amaral-Phillips

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