Successful artificial insemination of an Asian elephant at the National Zoological Park

Abstract

For decades, attempts to breed elephants using artificial insemination (AI) have failed despite considerable efforts and the use of various approaches. However, recent advances in equipment technology and endocrine-monitoring techniques have resulted in 12 elephants conceiving by AI within a 4-year period (1998)(1999)(2000)(2001)(2002). The successful AI technique employs a unique endoscope-guided catheter and transrectal ultrasound to deliver semen into the anterior vagina or cervix, and uses the ''double LH surge'' (i.e., identifying the anovulatory LH (anLH) surge that predictably occurs 3 weeks before the ovulatory LH (ovLH) surge to time insemination. This study describes the 6-year collaboration between the National Zoological Park (NZP) and the Institute for Zoo Biology and Wildlife Research (IZW), Berlin, Germany, that led to the refinement of this AI technique and subsequent production of an Asian elephant calf. The NZP female was the first elephant to be inseminated using the new AI approach, and was the fifth to conceive. A total of six AI trials were conducted beginning in 1995, and conception occurred in 2000. Semen was collected by manual rectal stimulation from several bulls in North America. Sperm quality among the bulls was variable and was thus a limiting factor for AI. For the successful AI, semen quality was good to excellent (75-90% motile sperm), and sperm was deposited into the anterior vagina on the day before and the day of the ovLH surge. Based on transrectal ultrasound, ovulation occurred the day after the ovLH surge. Pregnancy was monitored by serum and urinary progestagen, and serum prolactin analyses in samples collected weekly. Fetal development was assessed at 12, 20, and 28 weeks of gestation using transrectal ultrasound. Elevated testosterone measured in the maternal circulation after 36 weeks of gestation reliably predicted the calf was a male. Parturition was induced by administration of 40 IU oxytocin 3 days after serum progestagens dropped to undetectable baseline levels. We conclude that AI has potential as a supplement to natural breeding, and will be invaluable for improving the genetic management of elephants, provided that problems associated with inadequate numbers of trained personnel and semen donors are resolved.

Abnormal Reproductive Patterns in Przewalski's Mares Are Associated with a Loss in Gene Diversity1

“…In many ungulate species, such as the cow, ewe, and sow, the period of estrus is short (15,30, and 50 h, respectively [28]). However, in the domestic horse, estrogens increase during a period of at least 5 days coincidentally with follicular growth [10,25].…”

“…Assisted breeding, especially artificial insemination (AI), has been used as a tool to genetically manage ex situ populations of many wildlife species, such as the giant panda (Ailuropoda melanoleuca) [12,13], African elephant (Loxodonta africanus) [14], Asian elephant (Elephas maximas) [15], Eld's deer (Cervus eldii) [16], and scimitar-horned oryx (Oryx dammah) [17], among others. However, success required preliminary efforts to establish baseline information on reproductive patterns in females, including seasonality, length of reproductive cycle, and the timing of ovulation.…”

Pretreatment of Asian elephant (Elephas maximus) spermatozoa with cholesterol-loaded cyclodextrins and glycerol addition at 4°C improves cryosurvival

“…Although reproduction through natural breeding is desired within the North American elephant population, it is often not possible. Few breeding centres, a limited number of bulls, increased public objection to moving live elephants for breeding, logistics and cost associated with transport, as well as possible social incompatibility of paired individuals, reduce the opportunities for natural breeding in North America (Brown et al 2004). As a result, artificial insemination (AI) with fresh or chilled semen has been used extensively to supplement natural breeding within the North American captive elephant population.…”

Mutual benefits of research collaborations between zoos and academic institutions

“…Examples of breeding programs include for the red bird of paradise (Paradisaea rubra) at the New York Zoological Park [Hundgen et al, 1991], artificial insemination programs for Asian elephants (Elephas maximus) at the National Zoological Park [Brown et al, 2004], breeding and rearing of the Tarictic hornbill (Penelopides panini) at the Jurong Bird Park, [Buay, 1991], behavioral management and breeding programs for giant pandas (Ailuropoda meanoleuca) at the Wolong Breeding Center [Zhang et al, 2004], artificial incubation of bird eggs at the Zoological Society of San Diego, [Kuehler and Good, 1990], breeding programs for several species of duikers at the Los Angeles Zoo [Barnes et al, 2002], and hand-rearing of the secretary bird (Sagittarius serpentarius) at the Oklahoma City Zoo, [Todd, 1988].…”