Reproductive steroid hormones and ovarian activity in felids of the Leopardus genus

Abstract

Reproductive endocrine patterns were characterized in female ocelots (Leopardus pardalis; n = 3), tigrinas (Leopardus tigrinus; n = 2), and margays (Leopardus wiedii; n = 2) housed in captivity in southern Brazil. Females were maintained as singletons and exposed to natural fluctuations in photoperiod. Cyclic changes in ovarian steroids were monitored by analyzing estrogen and progestogen metabolites in fecal samples collected five times weekly for 14 to 18 months. Based on intervals between fecal estrogen peaks, mean (+/- SEM) duration of the estrous cycle was 18.4 +/- 1.6 days for the ocelots (range, 7-31 days; n = 75 cycles), 16.7 +/- 1.3 days for the tigrinas (range, 11-27 days; n = 23 cycles), and 17.6 +/- 1.5 days for the margays (range, 11-25 days; n = 32 cycles). Fecal progestogen analyses combined with two laparoscopic observations of the ovaries confirmed that ocelots and tigrinas did not ovulate spontaneously. In contrast, non-mating-induced luteal phases of 40.1 +/- 6.3 days in duration (range, 30-60 days) were observed frequently in both margays. There was no evidence of gonadal seasonality in margays in either follicular or luteal activity. In ocelots, cyclic changes in estrogen excretion were observed during each month of the year; however, only one female cycled continuously. In the other two ocelots, periods of acyclicity of several months' duration were observed. It was not possible to conclude whether tigrinas were aseasonal because estrous cyclicity was observed in only one of two individuals. In the female that cycled, a 3-month period of acyclicity was observed in the late fall/early winter. These data demonstrate similarities among three felid species of the genus Leopardus, including evidence they are polyestrous but experience unexplained periods of ovarian inactivity. Only the margays differed by exhibiting occasional spontaneous, non-mating-induced ovulations. Historically, these species have not bred well in captivity. However, it is hoped that understanding the biological similarities and differences among them could lead to improved management strategies that may one day result in increased reproductive success. Zoo Biol 20:103-116, 2001. Copyright 2001 Wiley-Liss, Inc.

Fecal 20-oxo-pregnane concentrations in free-ranging African elephants (Loxodonta africana) treated with porcine zona pellucida vaccine

“…Concerning seasonality, the generated endocrine correlates in pZP-treated individuals all remained in agreement with findings in literature regarding untreated populations [26,29]. Seasonal influences on reproductive steroid hormones have been widely reported in a variety of species [51][52][53] as well as African elephants [26,29]. As a consequence of low rainfall experienced during the dry season, quality and availability of food and water decline [26].…”

Approaches and efficacy of artificial insemination in felids and mustelids

“…Analysis of fecal hormones also has allowed characterizing which felid species experience induced (i.e., oocyte release only after copulation or hormonal stimulation) or spontaneous (corpora lutea [CL] formation in the absence of a male and copulation) ovulation. Interestingly, the cheetah [23], tiger (Panthera tigris) [17,24], tigrina (Leopardus tigrinus) [25] and ocelot (Leopardus pardalis) [25] appear to be exclusively induced ovulators, similar to the puma (Puma concolor) [26], Siberian tiger (Panthera tigris altaica) [27] and snow leopard (Uncia uncia) [28] assessed in earlier studies using blood analyses. In contrast, spontaneous ovulation during natural estrous cycles has been reported in the clouded leopard [29], lion (Panthera leo) [30], leopard (Panthera pardus) [31]; margay (Leopardus wiedii) [25], Pallas' cat [20] and fishing cat (Prionailurus viverrinus) [32,33].…”

Induction of ovarian activity and ovulation in an induced ovulator, the maned wolf (Chrysocyon brachyurus), using GnRH agonist and recombinant LH

“…Baseline concentrations of fecal progestagens were determined by an iterative process whereby progestagen values in excess of 1.5 standard deviations (SDs) of the baseline were removed from the dataset until no values exceeded 1.5 SD of the baseline mean [25]. Baseline progestagens were reported as the mean of the remaining values, and this process was repeated each year for each female.…”