Putman S.B.,Smithsonian Conservation Biology Institute |
Putman S.B.,George Mason University |
Brown J.L.,Smithsonian Conservation Biology Institute |
Franklin A.D.,Smithsonian Conservation Biology Institute |
And 5 more authors.
PLoS ONE | Year: 2015
Because of poor reproduction after the lifting of an 8-year breeding moratorium, a biomedical survey of female lions in U.S. zoos was initiated in 2007. Fecal estrogen (FEM), progestagen (FPM) and glucocorticoid (FGM) metabolites were analyzed in samples collected 3-4 times per wk from 28 lions at 17 facilities (0.9-13.8 yr of age) for 4 mo-3.5 yr and body weights were obtained ~monthly from 17 animals at eight facilities (0.0-3.0 yr of age). Based on FEM, estrous cycle length averaged 17.5 ± 0.4 d in duration, with estrus lasting 4.4 ± 0.2 d. All but one female exhibited waves of estrogenic activity indicative of follicular activity; however, not all females expressed estrous behaviors (73%), suggesting silent estrus was common. Female lions experienced puberty earlier than expected; waves of estrogenic activity were observed as young as 1.1 yr of age, which may be related to a faster growth rate of captive vs. wild lions. Mean gestation length was 109.5 ± 1.0 d, whereas the non-pregnant luteal phase was less than half (46.0 ± 1.2 d). Non-mating induced increases in FPM were observed in 33% of females housed without a male, consistent with spontaneous ovulation. A number of study animals had been contracepted, and the return to cyclicity after treatment withdrawal, while variable, was ~4.0 yr and longer than the 1-yr expected efficacy, especially for those implanted with Suprelorin. For FGM, there were no differences in overall, baseline or peak mean concentrations among the age groups or across seasons, nor were there any relationships between reproductive parameters and FGM concentrations. Overall, results suggest that poor reproduction in lions after the breeding moratorium was not related to altered adrenal or ovarian steroid activity, but for some females may have been a consequence of individual institutions' management decisions.
MacGregor M.J.,University of Wyoming |
Perkins E.G.,University of Wyoming |
Asa C.,Wildlife Contraception Center |
Skinner D.C.,University of Wyoming
Journal of Zoo and Wildlife Medicine | Year: 2013
Coyotes (Canis latrans) are predators of livestock. Current management programs, primarily lethal control, are ineffective for long-term management of predation. Controlling reproduction of coyotes may reduce depredations if territory fidelity is maintained by breeding pairs. Surgical sterilization is successful in altering predatory behaviors of coyotes but may provide a challenge for field implementation. An alternative approach is the development of a one-time non-transferable chemical contraceptive. This research is investigating the efficacy of a single high dose treatment of a sustained release gonadotropin-releasing hormone agonist, deslorelin, on coyotes as a long term contraceptive. Male coyotes were administered 47 mg deslorelin subcutaneously. Preliminary data show full suppression of the reproductive axis for over 12 mo as indicated by complete absence of sperm. © Copyright 2013 by American Association of Zoo Veterinarians.
Larson S.,Seattle Aquarium |
Belting T.,Seattle Aquarium |
Rifenbury K.,Sea For Life |
Boutelle S.M.,Wildlife Contraception Center
Zoo Biology | Year: 2013
The sea otter (Enhydra lutris) is a popular exhibit animal in many zoos and aquariums worldwide. Captive sea otters from these populations are owned by the United States Fish and Wildlife Service (USFWS). The USFWS has requested that these sea otters be prevented from breeding in order to save captive space for wild rescued animals. Sea otters are often housed in mixed sex groups, therefore a chemical contraceptive method or surgical removal of gonads must be used to prevent potential pregnancy. The contraceptive, Suprelorin® or deslorelin, has been used in many different species to effectively suppress reproduction but duration of effect may vary not only between species but also individuals. Here, we report the effects of one to several consecutive deslorelin implants on gonadal reproductive hormones found in fecal samples from six captive sea otters (two males and four females) compared to two control otters (one male and one female) housed at three zoological institutions. We documented the longitudinal hormone signatures of many stages of the contraceptive cycle including pretreatment (PT), stimulatory phase (S), effective contraception (EC), and hormone reversal (HR) that was characterized by a return to normal hormone levels. Deslorelin was found to be an effective contraceptive in sea otters and was found to be reversible documented by a live birth following treatment, however the duration of suppression in females was much longer than expected with a 6-month and a 1-year implant lasting between 3 and 4 years in females. © 2012 Wiley Periodicals, Inc.
Asa C.S.,Saint Louis Zoo |
Asa C.S.,Wildlife Contraception Center |
Bauman K.L.,Saint Louis Zoo |
Devery S.,Royal Veterinary College University of London |
And 4 more authors.
Zoo Biology | Year: 2013
The ability to safely and effectively manage reproduction is central to the success of AZA captive-breeding programs. Although the AZA Wildlife Contraception Center routinely monitors contraceptive safety, there have been no studies that compare the effects of contraceptive use to separation of males from females, the other option for preventing reproduction. We used retrospective medical records and pathology reports submitted by AZA and related facilities for the seven AZA-managed canid species to assess rates of uterine pathology relative to female reproductive life histories. Our results showed that the prevalence of both pyometra and endometrial hyperplasia (EH) was associated not only with treatment with the two most common contraceptives (Suprelorin® and MGA implants) but also with the number of years barren (i.e., not producing a litter and not contracepted). Rates of pyometra and EH were especially high in African painted dogs and red wolves, but lowest in swift and fennec foxes. The number of years producing a litter had a low association, suggesting it could be protective against uterine pathology. A more recently developed Suprelorin® protocol using Ovaban® to prevent the initial stimulation phase, followed by implant removal when reversal is desired, may be a safer contraceptive option. These results concerning the relationship between reproductive management and uterine health have important implications for AZA-managed programs, since the unsustainability of many captive populations may be due at least in part to infertility. Managing a female's reproductive lifespan to optimize or maintain fertility will require a reconsideration of how breeding recommendations are formulated. © 2013 Wiley Periodicals, Inc.