Preliminary studies on the effect of yeast culture supplementation on nitrate/nitrite induced methemoglobinemia in lambs and steers.

Lambs and steers were fed low-nitrate hay and supplements which supplied 0.045 kg (lambs) or 0.114 kg (steers) of yeast culture/head/day for 14 and 12 days, respectively, prior to feeding high-nitrate sorghum-sudan hay. Nitrate consumption of lambs by 6 hours after feeding the high-nitrate (29,300 ppm NO3) hay was similar among treatments and ranged from 0.3 to 0.5 g/kg body weight/day over 3 challenge days. Similar rates of nitrate consumption occurred with steers. Blood methemoglobin concentrations, used as a measure of nitrate/nitrite exposure in lambs and steers fed yeast culture, were not lower than those of control animals. The results of the study indicate that yeast culture did not decrease the methemoglobinemia produced by consumption of high-nitrate forages by sheep or cattle.