Effect of Adding Nitrate or Nitrite to Drinking Water on the Utilization of Carotene by Growing Swine

Abstract
Summary Eighty purebred Yorkshire pigs were used in two experiments to determine the effects of nitrate and nitrite in drinking water on the utilization of dietary carotene. Liver vitamin A stores were significantly reduced in pigs receiving 0.3% NO3 (from KN03) and beta-carotene. Pigs receiving 0.3% NO3 and preformed vitamin A had liver stores which were not significantly different from controls. The addition of nitrate to drinking water had no significant effect on average daily gain or methemoglobin levels. Pigs supplied water containing NO2 (from KNO2) had vitamin A liver stores which were significantly (P<.05) lower than the controls. Water containing 0.08% NO2 significantly reduced liver vitamin A regardless of the source of vitamin A activity fed. Nitrite supplied at levels of 0.02% and 0.08% significantly (P<.01) reduced average daily gain and caused a marked reduction in average daily feed consumption. Methemoglobin values for pigs supplied water containing 0.08% NO2 were significantly (P<.01) higher than the control values. Copyright © 1967. American Society of Animal Science . Copyright 1967 by American Society of Animal Science