title: Characteristics of the oestrous cycle of Iberian red deer (Cervus elaphus hispanicus) assessed by progesterone profiles.
abstract: This study examines the length of the oestrous cycle in 16 Iberian red deer females assessed by means of changes in progesterone concentrations, along with the changes in the profile of this hormone. Samples were collected three occasions per week from the week after calving (15 May to 15 June) up to May of the following year. The oestrous cycle lasted 19.57+/-0.29 days (range 10-27 d) calculated in 130 oestrous cycles examined. Progesterone titres did not rise above 0.5 ng/ml in the follicular phase, except in four samples. The maximum peak in progesterone concentration during the luteal phase remained above 1 ng/ml in most cases. Twenty-five percent of the individuals studied (4 out of 16) showed an oestrous cycle lasting shorter than the mean (15.2+/-0.30 days) before the start of the reproductive season, followed by a period of sexual inactivity. The standard progesterone profile in natural oestrous cycles rose from basal levels to those above 0.5 ng/ml four days after onset of oestrus, reached a peak of 1.71+/-0.07 ng/ml and then declined to less than 0.2 ng/ml after day 20. Following the rapid decline of progesterone after day 14, the concentration remained around the baseline level of 0.1 to 0.2 ng/ml during the immediate pre- and post-ovulatory phase of the cycle.
authors.affiliation: Departamento de Ciencia y Tecnología Agroforestal, ETSIA, Albacete, Spain. ajgarcia@cita-ab.uclm.es
authors.forename: Andres Jose
authors.initials: AJ
authors.lastname: Garcia
authors.forename: Tomas
authors.initials: T
authors.lastname: Landete-Castillejos
authors.forename: Amelia
authors.initials: A
authors.lastname: Gomez-Brunet
authors.forename: Jose Julian
authors.initials: JJ
authors.lastname: Garde
authors.forename: Laureano
authors.initials: L
authors.lastname: Gallego
mesh_terms: D000818:Animals; D003670:Deer / Q000502:physiology*; D030762:Estrous Cycle / Q000097:blood*; D005260:Female; D011374:Progesterone / Q000097:blood*; D012621:Seasons; D013030:Spain
chemical_list: D011374:Progesterone