The effect of 3-nitro-4-hydroxyphenylarsonic acid (3-nitro-hoechst) on egg production and food conversion of laying hens and residue analyses of muscle, organs and eggs

White Leghorn pullets were divided into two groups, each comprising 5 pens with 15 or 16 birds per pen. The experiment began when the birds were 20 weeks old and finished on the 500th day of life. The control group received a normal ration containing 16 per cent protein whilst the experimental group received the same ration supplemented with 50 p.p.m. 3-nitro-4-hydroxyphenylarsonic acid (3-nitro-hoechst).
Food consumption and egg weight were similar in both groups but the treated group laid 4 per cent more eggs. Although this was not significant, the treated group showed an overall improvement in the efficiency of food utilisation of 2.5 per cent.
For a period of 6 months the arsenic content of 10 eggs was determined weekly and after this time at fortnightly intervals. At the end of the experiment 10 birds of each group were killed and the arsenic contents of the heart, liver, kidneys, tibia, pectoral muscle and feathers were determined. The arsenic contents of the eggs, heart, kidneys, muscle and bone of the experimental birds were not significantly different from the controls. However, the liver of the birds fed the supplement contained twice and the feathers fifteen times as much arsenic as the control birds.