title: Pattern of secretion of luteinizing hormone and testosterone in the sexually mature male turkey.
abstract: Whether luteinizing hormone (LH) and testosterone (T) are secreted in pulsatile patterns was determined in sexually mature male turkeys. Turkeys were chronically cannulated and serially bled for three 8-hr periods covering the 24-hr day (14L:10D, n = 7, series B), or for two 12-hr periods covering the 24-hr day (14L:10D, n = 4, series C). Pulses of both LH and T occurred during both the light and dark portions of the 24-hr day. A portion of the secretory episodes of T, where the baseline level of LH was relatively low, was associated with prior peaks of LH secretion. Secretory episodes of T also occurred, where baseline levels of LH and T were both relatively high, without detection of prior peaks of LH. No differences were found between the photophase and scotophase portions of the photoperiod for either LH or T concentration. It is concluded that T is secreted in a pulsatile pattern in sexually mature male turkeys. However, LH is secreted in a pulsatile pattern only when baseline levels of both LH and T are relatively low. Neither LH nor T secretion is entrained by the photoperiod. Corticosterone was measured in hourly samples, but no changes in concentration occurred in association with the photoperiod.
authors.affiliation: Ohio State University, Department of Poultry Science, Wooster 44691.
authors.forename: W L
authors.initials: WL
authors.lastname: Bacon
authors.forename: J A
authors.initials: JA
authors.lastname: Proudman
authors.forename: D N
authors.initials: DN
authors.lastname: Foster
authors.forename: P A
authors.initials: PA
authors.lastname: Renner
mesh_terms: D000818:Animals; D001835:Body Weight; D003345:Corticosterone / Q000378:metabolism; D008027:Light; D007986:Luteinizing Hormone / Q000378:metabolism*; D008297:Male; D010507:Periodicity; D011863:Radioimmunoassay; D012661:Semen; D012727:Sex Characteristics; D013739:Testosterone / Q000378:metabolism*; D014422:Turkeys / Q000502:physiology*
chemical_list: D013739:Testosterone; D007986:Luteinizing Hormone; D003345:Corticosterone