Significant cattle deaths most commonly occur
when a producer feeds high-nitrate forages to
hungry cattle that are not adapted to nitrate. Every
fall, reports of cattle deaths increase at the start of
the winter feeding period. In this scenario, cattle
have been allowed to graze a pasture until there is
little or no forage remaining and the animals are
hungry. They are then fed round bales and rapidly
eat a large amount from one section of a bale. If
the hay is high in nitrate, and especially if a portion
of the bale is exceptionally high, death of
some animals is likely. Most producers have several
cuttings of hay on hand, and knowing the nitrate
levels will allow them to use the hay with the lowest
nitrate level at the start of the feeding period.