Effects of ferrous sulfate consumption on the performance of broiler chicks.

Ferrous sulfate is often used as a litter treatment to control ammonia. A series of experiments was conducted to evaluate the effects of single high and multiple low doses of ferrous sulfate (FeSO4-7H2O) on broiler chicks. In Experiment 1, broiler chicks were administered a single oral dose of ferrous sulfate. A direct relationship between mortality and the amount of ferrous sulfate administered was evident. The lethal dose that caused 50% mortality (LD50) for ferrous sulfate was calculated to be 7,010 mg/kg of body weight. In Experiment 2, the addition of ferrous sulfate to the diet at levels from .75 to 12% decreased feed consumption. Ferrous sulfate levels of 3% or greater lowered average daily gain and gain:feed ratios. In a pair-wise comparison preference test in Experiment 3, chicks significantly decreased consumption of a diet containing 3% ferrous sulfate but not of a diet with .375% ferrous sulfate. The results of these experiments indicate that ferrous sulfate can have adverse effects on mortality, weight gain, and feed efficiency of broiler chicks.