752 • Technologies To Maintain Biological Diversity 



Photo credit: Zoological Society oi San Diego 



New technologies in reproductive physiology offer 

 possibilities of producing large numbers of offspring 

 from many vertebrate species. Above, an osmotic pump 

 filled with gonadotropin-releasing hormone is prepared 

 for Insertion under the skin of a female iguana. The 

 iguana subsequently entered estrus and ovulated. 



pies, it also avoids problems restraining and 

 anesthetizing rare animals. 



Although reproductive problems in wild ani- 

 mals can often be solved through management 

 changes, hormone therapy can also be used for 

 infertility arising from age or unknown envi- 

 ronmental factors. In particular, gonadotropin- 

 releasing hormone has been used to initiate and 

 maintain estrous cycles and ovulation in mon- 

 keys, sheep, and cattle. It is administered 

 through a small osmotic pump implanted be- 

 neath the skin and appears to have facilitated 

 the birth of two cubs to a previously subfertile 

 cheetah (28). Similarly, a human fertility drug. 



clomid, is being considered to support ovula- 

 tion in female gorillas (9). 



Growing pressure for the international move- 

 ment of animal germplasm will also place an 

 increasing premium on knowledge of reproduc- 

 tive biology. In terms of animal safety, conven- 

 ience, and disease control, movement of semen 

 and embryos (either fresh or frozen) would be 

 preferable to the movement of animals. Al- 

 though the techniques to allow collection, pres- 

 ervation, transport, and use of these tissues are 

 relatively well developed in domestic animals, 

 comparable methods do not exist for wild 

 species. 



Artificial insemination (A.I.) is the introduc- 

 tion of semen into the female reproductive tract 

 by artificial means. It requires technologies to 

 allow collection of semen from the male, stor- 

 age of semen until it can be used, identifica- 

 tion of females in the proper stage of the es- 

 trous cycle, and deposition of semen at the 

 appropriate location in the female reproduc- 

 tive tract. Collection of semen from wild spe- 

 cies is usually accomplished by electroejacu- 

 lation, which involves stimulation of ejaculation 

 by application of a mild, pulsating electrical 

 current through a lubricated rectal probe. The 

 process requires restraint and anesthesia of the 

 male, and semen obtained with this procedure 

 is often less fertile than that obtained in a nat- 

 ural ejaculate. Use of A.I. likewise requires the 

 ability to assess the reproductive status of the 

 female quite accurately, and insemination pro- 

 cedures must be developed that are consistent 

 with the biochemical and physical character- 

 istics of the female reproductive tract. 



Although artificial insemination has been at- 

 tempted in many species of wild animals, it has 

 only been successful in a limited number and, 

 in most cases, with one animal in most species. 

 A.I. with frozen semen has been successful with 

 even fewer wild species (see table 6-4) such as 

 the wolf, gorilla, chimpanzee, and giant panda. 



Effective use of embryo transfer requires even 

 greater control of an animal's reproductive 

 processes (box 6-D and figure 6-1). Fertilized 

 ova and early embryos are recovered from the 



