AZA Wildlife Contraception Center Programme for Wild Felids and Canids

Abstract

Contents North American zoos began using melengestrol acetate (MGA) implants to control reproduction in wild felids in the mid‐1970s. Research linking MGA and other progestin‐based contraceptives to uterine and mammary pathology in canids as well as felids resulted in a shift to GnRH agonist implants (Suprelorin®: deslorelin, Peptech Animal Health, Australia). However, a recent study revealed an association between Suprelorin® and uterine pathology in canids, but that pathology was not found in canids treated with oral megestrol acetate (MA) for 2 weeks around the time of implant insertion to prevent the initial agonist stimulation phase. Thus, the AZA Wildlife Contraception Center (WCC) currently recommends Suprelorin® plus the 2‐week MA regimen for wild canids and felids. WCC research is now focusing on factors affecting Suprelorin® reversibility.

Characterization of Ovarian Steroid Patterns in Female African Lions (Panthera leo), and the Effects of Contraception on Reproductive Function

“…While lions treated with MGA have cycled and bred soon after implant removal (28 ± 4 d; N = 3) [ 88 ], sustained treatment (> 2 yr) with MGA is associated with reproductive organ pathologies in felids [ 39 ]. The AZA Wildlife Contraception Center (WCC) used to recommend using MGA for a maximum of 4 yr and removing the implants after 2 yr to allow for a pregnancy before retreatment [ 89 , 90 ]. But starting in ~2005, Suprelorin implants began to be used in lieu of MGA because no adverse effects had been linked to Suprelorin use in felids [ 91 ].…”

Investigation of the efficacy of the GnRH agonist deslorelin in mitigating intraspecific aggression in captive male Amur leopards (Panthera pardus orientalis)

“…Strategies aimed at reducing circulating androgens, including deslorelin implantation and castration have been implemented successfully in numerous species to reduce aggression (Asa et al, ; Bertschinger et al, , ; DeCaluwe et al, ; Knol & Egberink‐Alink ; Trigg et al, ), and other undesirable behaviors, such as marking in tomcats (Goericke‐Pesch, Georgiev, Antonov, Albouy, & Wehrend, ). In this report, intraspecific aggression between intact male leopards was mitigated by the placement of deslorelin implants enabling continued social housing of the pair.…”

“…These strategies are classified as either conservative (i.e., hormone‐based) or invasive (i.e., surgical castration). The gonadotropin‐releasing hormone (GnRH) agonist deslorelin has been found to be effective in reducing androgens in domestic and non‐domestic carnivores (Asa, Boutelle, & Bauman, ; Bertschinger et al, ; Bertschinger, Trigg, Jochle, & Human, ; Norton et al, ; Penfold et al, ; Trigg, Wright, Armour, Williamson, & Junaidi, ). A single 3 mg deslorelin implant reduced aggression in a black‐footed cat ( Felis nigripes ).…”

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

“…Historically, knowledge and specific recommendations regarding the use of contraceptive products and methods in wild animals has been poorly disseminated. The "Contraception Database" (CD) was created so that institutions housing captive wild animals could contribute contraceptive records and centralize this knowledge (Asa et al, 2012).…”

“…The first reports of contraceptive use in zoo felids came in the early 1970s with the use of synthetic progesterone products (Asa, 2005;Seal et al, 1976), primarily melengestrol acetate (MGA). These products have since been associated with uterine and mammary pathology and infertility in a variety of carnivores (Moresco & Agnew, 2013;Munson et al, 2002;Munson, 2006;Harrenstien et al, 1996;Kazensky et al, 1998); this has resulted in greater interest in using gonadotropinreleasing hormone (GnRH) agonist implants, including deslorelin acetate (DA) beginning in the early 2000s (Asa et al, 2012).…”