Abstract
It is considered that Hg will be transfered into milk, if cows take the feeds contaminated with PMA. To make clear this point, Hg-203 labelled PMA was administered orally to two lactating cows and six lactating goats, intravenously to two lactating cows. The excretion of Hg into feces and urine, the transfer of Hg into milk and the residue of Hg in some organs were studied.
Most of Hg of PMA administered orally was excreted into feces (70-85% of dose) and urine (2-5%). On the contrary, the transfer of Hg into milk was small in amount (0.2-0.8%), but continued for a long term. The residue of Hg in kidney was larger in amount, and higher in concentration than that in liver. However, the small amount of Hg was detected in brain (0.02-0.03%).
Hg of PMA administered intravenously was excreted into feces (40-48%), and urine (7%). The transfer of Hg into milk was the same as in the case of oral administration (0.6%). The residue of Hg in kidney was larger in amount, and higher in concentration than that in liver. The residue of Hg in brain was very small in amount (0.02%).
The period in which half amount of administered Hg was excreted, was 2-3 days in the case of oral administration, while, it was 20-25 days in the case of intravenous administration.
