Toxicity of mercuric chloride in Japanese quail as affected by methods of incorporation into the diet.

Three experiments were conducted with day-old Japanese quail. When mercuric chloride (HgCl2) was added to the diet as a dry salt, it produced higher mortality than when added as a solution or as a casein-premix. Averages of mortality at 4 weeks were 86%, 55%, and 33% when 500 ppm mercury as HgCl2 was added dry, in 95% ethanol, or as a casein-premix, respectively. The nature of solvent (ethanol, methanol, or water) had little or no effect. The addition of mercury as a HgCl2-casein premix produced the lowest mortality but increased the mercury content of the kidney. This suggests that casein did not reduce mortality by decreasing mercury absorption. A complete explanation of the phenomenon is not available at this time. Possibly, the solvent could facilitate the binding of mercury to some feed component, thereby affecting the mercury absorption, transport, and subsequent tissue distribution and making mercury less available to exert its toxicity.