Effects of Excess Dietary Iodine upon Rabbits, Hamsters, Rats and Swine

Abstract

Studies were conducted with rabbits, hamsters, rats and swine to determine the effects of excess iodine intake. Females were bred to normal males, potassium or sodium iodide were added to the diet during the latter portion of gestation and the females were permitted to litter normally. Observations were made for length of gestation, parturition time, lactation and survival of young. Two-hundred and fifty to 1000 ppm iodine fed for 2 to 5 days caused increasing mortality of newborn rabbits. Hamsters were not affected by 2500 ppm iodine except for slightly reduced feed intake and decreased weaning weight of the young. Gestation time for rats and hamsters was not affected by iodine; however, prolonged parturition was observed in rats. Female rats and rabbits re-bred after removal from dietary iodine produced and nursed litters normally. Swine were not affected by dietary levels of iodine which were toxic to rabbits and rats.