| Summary |
Experiments were conducted to investigate Pb concentrations in eggs from laying tsaiya ducks (Anas platyrhynchos var. domestica) dosed daily via gelatin capsule with different amount of Pb. In experiment 1, the doses of lead were equivalent to 0, 10, and 20 mg Pb / kg body weight for 3 months. No clinical syndromes involving Pb intoxication was found throughout the experiment period. The two levels of Pb consistently resulted in increases in the Pb content of blood. Lead residues in yolk and egg shell from lead-dosed ducks were significantly higher than from controls. However, Pb in albumens were generally low and were not influenced by Pb treatment. In experiment 2, the doses of lead were reduced to 0, 2, 4, 6 and 8 mg/ kg body weight for 1 month. Lead contents of whole blood from lead treated ducks were significantly higher than those of controls. Lead concetrations in yolk of 2 mg / kg group and control were not different significantly, whereas higher levels of Pb ( 4, 6, 8 mg / kg) increased the Pb concentrations in yolk. Lead concentrations in albumen and eggshell were not affected by Pb feeding at the dose of 8 mg/ kg and below.
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