title: Variations in circulating thyroxine and triiodothyronine concentration in relation to spring migration in rosy pastor, Sturnus roseus.
abstract: In rosy pastor, Sturnus roseus, the spring premigratory fattening observed during April was preceded by a significant increase in circulating thyroxine (T4) and triiodothyronine (T3) concentrations. Plasma T4 and T3 both declined significantly by May when in nature the migrating conspecifics had departed for their breeding ground. A possible role of thyroid hormones in the migratory disposition of this bird is, therefore, suggested.
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D001717:Birds / Q000502:physiology*; D001835:Body Weight; D008297:Male; D012621:Seasons; D013737:Testis / Q000502:physiology; D013974:Thyroxine / Q000097:blood*; D014284:Triiodothyronine / Q000097:blood*
chemical_list: D014284:Triiodothyronine; D013974:Thyroxine