Optimizing fixed-time laparoscopic artificial insemination in the jaguar

Abstract: The jaguar faces significant threats to survival from habitat fragmentation/loss and poaching. Conservation efforts include maintaining ex situ populations in zoos, but breeding success remains limited, necessitating the development of assisted reproductive technologies. This study aimed to optimize ovarian synchronization and artificial insemination (AI) protocols for jaguars by evaluating ovarian follicular activity during oral altrenogest treatment and in response to equine chorionic gonadotropin (eCG)/porcine luteinizing hormone (pLH) regimens, and assessing fertility outcomes with laparoscopic AI. In experiment 1, females were fed altrenogest (0.044 or 0.088 mg/kg, n = 2 per dose) daily for 45 days, but neither dose suppressed ovarian activity. In experiment 2, females received 0.088 or 0.176 mg/kg altrenogest (n = 2 per dose) for 45-48 days and then the alternate dose six months later. After a 5-day withdrawal, 600 IU eCG and 5,000 IU pLH (82 h interval) were administered intramuscularly. All eight cycles produced multiple follicles, but ovulation rates were low and no pregnancies occurred. In experiment 3, five females received 0.176 mg/kg altrenogest, followed by a 7-day withdrawal, 600 IU eCG, and 10,000 IU pLH (90-92 h interval). All females achieved multiple ovulations, and one female conceived, delivering a live cub after 103 days - the first jaguar ever produced from AI. In summary, altrenogest and eCG/pLH treatment following species-specific adjustments was effective for ovarian synchronization in the jaguar. The birth of a live cub following AI validates the effectiveness of this hormone regimen and highlights the potential of AI for population management of this imperiled felid.