Modeling the dynamics of radioiodine in dairy cows.

A metabolically based model of radioiodine transfer in cows was applied to previously collected data. The model required some modification and reparameterization before it could describe the measured data satisfactorily. In particular, significant fecal excretion of radioiodine needed to be considered. The model was used to predict the effect of dietary intake of stable iodine on the transfer of radioiodine to milk. Increased dietary intake asymptotically increased the proportion of radioiodine excreted via milk.