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1.
Zoo Biol ; 26(6): 441-60, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19360593

RESUMO

The objective of this study was to evaluate the effects of different captive housing conditions on reproductive cyclicity and adrenocortical activity in adult females of two small-sized felid species, the tigrina (Leopardus tigrinus; n = 3) and margay (Leopardus wiedii; n = 2). Females were housed as singletons and subjected to three enclosure conditions over successive time periods: Phase I-large, enriched enclosures for 3 months; Phase II-small, empty enclosures for 5.5 months; Phase III-the same small enclosures enriched with branches and nest boxes for 6.5 months. Fecal samples were collected five times weekly throughout the study for analysis of progestagen, estrogen, and corticoid metabolites. On the basis of observed behaviors, stereotypic pacing was more frequent before feeding for all cats, regardless of enclosure conditions. Both species displayed a bimodal activity pattern, with peaks occurring at nightfall and dawn. All animals exhibited agitated behavior, characterized by a high frequency and duration of stereotypic pacing, primarily during the first 3 days after moving to the small empty enclosures. On the basis of hormonal analyses, ovarian follicular activity decreased and corticoid concentrations increased in tigrinas after transfer to the small barren cages compared to the patterns observed in the initial large, enriched enclosures. Corticoid concentrations in tigrinas then declined after small cage enrichment. Margay females exhibited increased corticoid excretion during Phases II and III, but in contrast to tigrinas, concentrations remained high even after cage enrichment. It was further showed that enriching the small enclosures was insufficient to reestablish normal ovarian activity within the time frame of the study for both species. In summary, margay and tigrina females exhibited distinct elevations in corticoid concentrations after transfer from large enriched enclosures to smaller barren cages that corresponded with agitated behavior, especially immediately after transfer. Fecal corticoid concentrations were reduced after cage enrichment in tigrinas, but not in margays. Although only a few individuals were evaluated, data suggest there may be species differences in response to captive environmental conditions. Overall results emphasize the importance of enclosure dimensions and enrichment when designing species appropriate environments for improving the health and reproductive fitness of threatened species. Zool Biol 26:441-460, 2007. (c) 2007 Wiley-Liss, Inc.

2.
Theriogenology ; 57(8): 2027-41, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12066863

RESUMO

Captive adult male ocelots (Leopardus pardalis, n = 3), margays (L. wiedii, n = 3) and tigrinas (L. tigrinus, n = 4) in two locations in southern Brazil were studied for 14 consecutive months to evaluate the effect of season on testicular function. Reproductive evaluations, including testicular measurements, electroejaculation and blood collection were conducted monthly. Fecal samples were collected weekly for androgen metabolite analysis to assess testicular steroidogenic activity. Ocelots had the highest number of motile spermatozoa in the ejaculate (114.7+/-15.8 x 10(6); P < 0.05), the highest percentage of morphologically normal spermatozoa (82.4+/-1.2%; P < 0.05) and the highest concentration of fecal androgens (1.71 vs. 0.14 microg/g; P < 0.05). Margays and tigrinas had lower numbers of motile spermatozoa (23.4+/-2.8 x 10(6), 74.2+/-8.9 x 10(6), respectively), lower percentages of morphologically normal spermatozoa (57.4+/-2.8, 59.2+/-3.5%, respectively), and lower fecal androgen concentrations (0.15+/-0.01, 0.23+/-0.01 microg/g, respectively). Serum testosterone concentrations were similar among the three species. Fecal androgen concentrations were not affected by season, with the exception of the ocelot where concentrations were higher (P < 0.05) in the summer. Ejaculates were collected throughout the year; however, peaks in average sperm production were observed during the summer for all species. In summary, this study has identified several species differences in male testicular traits among ocelots, margays and tigrinas. Results of longitudinal reproductive assessments suggest males of each species are capable of breeding throughout the year.


Assuntos
Androgênios/análise , Carnívoros/fisiologia , Fezes/química , Estações do Ano , Sêmen/fisiologia , Testosterona/sangue , Animais , Carnívoros/anatomia & histologia , Masculino , Pênis/anatomia & histologia , Fotoperíodo , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Temperatura , Testículo/anatomia & histologia
3.
Zoo Biol ; 20(2): 103-116, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11429781

RESUMO

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.

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