Effectiveness of Deslorelin Implants in Suppressing Egg Production in a White‐Naped Crane ( <i>Antigone vipio</i> ): A Case Study

In the Northern Hemisphere, white-naped cranes breed from April to early June. Females typically produce two eggs per clutch with each season having one to four clutches per year. Egg production beyond the species' natural output can significantly impact an individual's health as significant amounts of calcium are required to form the eggshell. The objective was to evaluate the effectiveness of deslorelin acetate (Suprelorin) in suppressing gonadal function and egg production of a 39-year-old female white-naped crane with a history of long breeding seasons and excessive egg laying. Deslorelin acetate (9.4 mg) implants were administered s.q. at 1- or 3-month intervals over four breeding seasons. Fecal samples were collected 1-3 times/week and gonadal hormones were extracted and analyzed. Egg production was recorded. Analysis showed that deslorelin acetate (9.4 mg) implanted s.q. twice at a 3-month interval beginning at the expected start of the breeding season was not fully effective in suppressing gonadal function and egg production. The following breeding season, three deslorelin acetate 9.4 mg implants were administered at ~1-month intervals beginning at the expected start of the breeding season. This protocol was more effective at suppressing gonadal hormone production and egg production. Our results demonstrate a timeseries of how deslorelin acetate impacts reproductive function in white-naped cranes, though further studies should include the effects of implant after cessation.