Gastrointestinal Uptake of 144Ce in the Neonatal Mouse, Rat and Pig

Abstract

The uptake of 144Ce from the gastrointestinal tract of neonatal mice, rats and pigs was investigated. Although poorly absorbed by adults, cerium was absorbed to a considerable extent by neonates of all three species. The group of mice and rats dosed within 6 hr after birth had initially greater absorption and retention at the earlier necropsy times than the group of animals dosed between 6 and 24 hr. By 21 days, differences in retention between these two groups were minimal. We observed that mice absorbed and retained the most cerium, rats followed with less, and pigs with even less.