title: [The infradian rhythm in changes of thyroxine level and related periodicity of feather replacement during the molting in passerine birds].
abstract: In the course of 15 days, the thyroxine and corticosterone level was measured daily in blood serum of molting starlings, Sturnus vulgaris, by use of enzyme immunodetection method. Revealed are three-day rhythm in changes of thyroxine level and four-day one in changes of corticosterone level, both rhythms being synchronized in different birds. A beginning of growth of new oar feathers coincides with maximum thyroxine concentration in blood serum and also demonstrates a three-day period. In free-living passerine birds (Passer montamus, Parus major, Chloris chloris) a three-day rhythm is found in the dynamics of feather replacement. This rhythm is manifested synchronously in the studied species that differ in timing of post-nuptial molting. Established is the synchronous manifestation of three-day rhythm in changes of thyroxine level and feather replacement during molting in different passerine species and different birds of the same species.
authors.forename: M E
authors.initials: ME
authors.lastname: Diatroptov
mesh_terms: D000818:Animals; D001683:Biological Clocks / Q000502:physiology*; D003345:Corticosterone / Q000097:blood; D005241:Feathers / Q000254:growth & development*; D018978:Molting / Q000502:physiology*; D046109:Passeriformes / Q000097:blood / Q000502:physiology*; D013045:Species Specificity; D013974:Thyroxine / Q000097:blood*
chemical_list: D013974:Thyroxine; D003345:Corticosterone