Cloning for the Twenty-First Century and Its Place in Endangered Species Conservation.

Cloning as it relates to the animal kingdom generally refers to the production of genetically identical individuals. Because cloning is increasingly the subject of renewed attention as a tool for rescuing endangered or extinct species, it seems timely to dissect the role of the numerous reproductive techniques encompassed by this term in animal species conservation. Although cloning is typically associated with somatic cell nuclear transfer, the recent advent of additional techniques that allow genome replication without genetic recombination demands that the use of induced pluripotent stem cells to generate gametes or embryos, as well as older methods such as embryo splitting, all be included in this discussion. Additionally, the phenomenon of natural cloning (e.g., a subset of fish, birds, invertebrates, and reptilian species that reproduce via parthenogenesis) must also be pointed out. Beyond the biology of these techniques are practical considerations and the ethics of using cloning and associated procedures in endangered or extinct species. All of these must be examined in concert to determine whether cloning has a place in species conservation. Therefore, we synthesize progress in cloning and associated techniques and dissect the practical and ethical aspects of these methods as they pertain to endangered species conservation.

Island Life: Use of Activity Budgets and Visibility to Evaluate a Multi-Species Within-Zoo Exhibit Move.

Modern zoos strive to construct habitats which both enable and encourage animals to engage in species-specific behaviour, without compromising their visibility to visitors. Here, we present the findings of a within-zoo move to a custom-built exhibit (Islands at Chester Zoo, UK) with respect to the behaviour of four mammal species; the Sumatran orangutan (Pongo abelii), crested macaque (Macaca nigra), Malayan tapir (Tapirus indicus) and the Malayan sun bear (Helarctos malayanus). We used full activity budgets along with Compositional Data Analysis (CoDA) to gain insight into how the move to a more naturalistic exhibit influenced behaviour. Engagement in abnormal behaviour remained low during the study period for all four species, suggesting no adverse responses to the change in environment. Following the move, both the non-human primate species spent more time engaged in positive social interactions with conspecifics, highlighting the importance of social support during enclosure moves. Time spent visible to the public was largely unaffected by the enclosure move for the Sumatran orangutan, whilst the movement to a new environment increased visibility for the Malayan sun bear and decreased visibility for the crested macaque and Malayan tapir. We demonstrate the value of monitoring behaviour throughout the translocation of zoo-housed species and outline the positive behavioral impacts of providing individuals with naturalistic, species-appropriate environments.

DESLORELIN (SUPRELORIN®) USE IN NORTH AMERICAN AND EUROPEAN ZOOS AND AQUARIUMS: TAXONOMIC SCOPE, DOSING, AND EFFICACY.

The Association of Zoos and Aquariums Reproductive Management Center (RMC) in the US and the European Association of Zoos and Aquaria Reproductive Management Group (RMG) in Europe monitor efficacy of contraceptive products in participating institutions and use those results to inform contraceptive recommendations. This study used the joint RMC-RMG Contraception Database to analyze efficacy of deslorelin implants (Suprelorin®), a contraceptive used in a wide range of mammalian taxa. More recently its use has increased in birds and in some reptiles and fish. Deslorelin, a gonadotropin-releasing hormone (GnRH) agonist, stimulates the reproductive system before downregulating receptors on pituitary cells that produce hormones that stimulate gonadal steroids in both males (testosterone) and females (estradiol and progesterone), interrupting sperm production and ovulation, respectively. Nevertheless, it has been used mostly in females. Efficacy has been high in mammals, with failures resulting in offspring in only 1.3% of treated individuals and 0.5% of treatment bouts. The failure rate has been higher in birds, with 14.7% of individuals in 7.2% of bouts producing eggs, perhaps reflecting differences in avian GnRH molecules. Too few reptiles and fish have been treated for meaningful analysis. Although deslorelin appears very safe, a possible exception exists in carnivores, because the stimulatory phase can result in ovulation and subsequent sustained progesterone secretion that may cause endometrial pathology. However, the stimulatory phase can be prevented by treatment with megestrol acetate for 7 d before and 7 d after implant insertion. The two current formulations of Suprelorin are effective for minimums of 6 (4.7 mg) or 12 mo (9.4 mg). The data indicate that Suprelorin is an effective and safe contraceptive option for female mammals, although it may not be effective in males of some mammalian species. Further research is needed to ascertain its usefulness in nonmammalian taxa.

Reproductive males are effective at managing conflict in captive Sulawesi crested macaques (Macaca nigra).

Group size, density, and composition significantly influence the expression of agonism and, as demography is frequently manipulated in captivity, natural mechanisms of conflict management may be disrupted. Here, we examine how changes to the social and physical environment of a captive group of Sulawesi crested macaques, Macaca nigra, influenced mechanisms of conflict management. The initial group was comprised of females, juveniles, and castrated males; under a series of management interventions, the group was moved to a new enclosure, 75% of the castrated adult males were removed, 67% of the females were contracepted, a novel, intact male was introduced, and the group was allowed access to an outdoor enclosure. Despite a decreasing trend in aggression following the changes to the social group, we found no significant differences in aggression or intervention behavior in the 5-week periods immediately following changes to the social group, apart from a significant decrease in aggression following the introduction of the novel male. This decrease in the frequency of aggression was still evident 10 weeks after the interventions occurred, and was coupled with a decrease in the intensity of aggression. Moreover, the intensity of aggression as well as the frequency of aggression and intervention were significantly lower under low-density conditions. Our results highlight how management changes to the social and physical environment can influence aggressive behavior, albeit following a period of acclimation. We discuss the relative impacts of social group composition, social density, and individual reproductive status on the management of conflict behavior in a captive setting.

The past, present and future of hormonal contraceptive use in managed captive female tiger populations with a focus on the current use of deslorelin acetate.

Tigers (Panthera tigris spp.) are endangered in the wild; ensuring sustainable insurance populations requires careful planning within zoological collections. In captive situations, contraceptives are often used to control breeding and ensure genetically viable populations that contain manageable numbers of animals; reversible contraceptives are ideal because they offer flexibility for breeding management. Historically, synthetic progestins, such as melengestrol acetate implants, were used in female tigers, but these are associated with an increased risk of reproductive pathology and subsequent infertility. Recent management advice to ex-situ collections has been to transition to the use of gonadotropin-releasing hormone agonists, such as deslorelin acetate implants, which do not appear to have a similar risk of reproductive pathology but are associated with highly variable reversal times in exotic felids. Using data from 917 contraceptive records in female tigers captured by the Association of Zoos and Aquariums Reproductive Management Center and the European Association of Zoos and Aquaria Reproductive Management Group's joint Contraception Database and from supplementary surveys, this study reviews the changing use of contraceptives in captive female tigers. The aim was to describe the historical and current use of contraceptives and provide a comprehensive assessment on the use of deslorelin implants, including data on product protocols, efficacy, pathology, and reversibility. This study determined that current dose, frequency, reversibility, and anatomical placement sites of deslorelin implants are highly variable, indicating that specific, readily available, unified, evidence-based recommendations on the use of deslorelin would be useful for future contraceptive use in managed tiger populations.

ASSESSING THE EFFICACY OF DESLORELIN ACETATE IMPLANTS (SUPRELORIN) IN ALTERNATIVE PLACEMENT SITES.

Hormonal contraception is being increasingly used to manage captive animals in zoological collections. Many of the animals placed on contraception are of genetic importance within captive breeding programs; therefore, it is imperative that the application of contraceptive products minimize potential side effects and facilitate a return to fertility if required. Deslorelin acetate implants (Suprelorin®) are one example of a hormonal contraceptive that is frequently used in captivity as they are easy to use and effective in most species. It is hypothesized that removing implants may hasten reversal of contraception treatment; therefore, placement in a location where they can easily be recovered is advocated. In this report, the efficacy and safety of Suprelorin implants placed in their recommended site between the scapulae is compared with alternative placement sites where implants can more easily be located for removal. Using the European Association of Zoos and Aquariums (EAZA) Group on Zoo Animal Contraception (EGZAC) Contraception Database, rates of success, failure, and reversal in 561 records of Suprelorin use in European collections are compared. Of these, 357 have information relating to the location of implant placement. When correctly applied, rates of efficacy were high (>99%) irrespective of placement site. Rates of reversal were 33.3% higher in alternative placement sites, although in most cases it is unknown whether implants were removed or not. In conclusion, the placement of Suprelorin implants in alternative sites does not negatively affect the efficacy, facilitating at the same time implant removal, minimizing potential side effects, and reducing reversal time, allowing for effective use in captive conservation breeding programs.