The effect of pharmacological levels of dietary vanadium on the egg production, shell thickness and egg yolk cholesterol in laying hens and coturnix.

The addition of 100 p.p.m. of vanadium to a ration for White Leghorn laying hens caused a significant increase (p less than 0.01) in the egg shell thickness, but did not cause any significant change in the production, egg weight or egg ypok cholesterol content. The addition of 300 p.p.m. of vanadium caused a severe depression in the egg production which was the only symptom of vanadium toxicity to be observed. The addition of 50, 100, 200 or 300 p.p.m. vanadium to the ration of laying coturnix did not cause any significant change in egg production, egg weight, or egg yolk cholesterol content. The addition of the same levels of vanadium to one-day old male coturnix chicks did not cause any significant growth depression or mortality. We suggest that coturnix may be more resistant to vanadium toxicity than chickens.