title: Post concentrations of thyroxine in plasma of dairy cows.
abstract: Concentrations of thyroxine in blood plasma were measured by radioimmunoassay in 32 dairy cows postpartum and during estrous cycles. Mean concentrations of thyroxine declined from 1 to 2 days postpartum to 5 or 6 days postpartum. Concentrations of thyroxine remained low at 7 to 10 days postpartum and during the first estrous cycle. During subsequent estrous cycles concentrations of thyroxine were elevated to those 1 or 2 days postpartum.
mesh_terms: D000818:Animals; D002417:Cattle / Q000097:blood*; D004971:Estrus; D005260:Female; D049590:Postpartum Period; D011247:Pregnancy; D013974:Thyroxine / Q000097:blood*
chemical_list: D013974:Thyroxine