Factors influencing the retention of an oral dose of radioactive manganese by the chick.

Abstract

1. In two experiments, involving 110 chicks up to 5 weeks of age, retention of an oral dose of 54Mn was always low; less than 5%.2. There were no significant differences in retention by hybrid broiler cocks, hybrid layer cocks, and hybrid layer pullets, nor was retention affected by the period of fasting, i.e. 1 ½ or 24 h, before dosing.3. Two-weeks-old birds retained 58% more radioactive manganese than 5-week-old birds, and retention in birds killed 24 h after the dose was only 64% of that in birds killed 4 h after the dose.4. With the addition to a fixed dose of 54Mn of increasing quantities of non-radioactive Mn retention decreased only from 2.52% with no Mn added to 1.02% with 5000 μg Mn added, representing a very large increase in total retention of Mn.