Endangered_Species

The evolution of reproductive biotechnology has been of great assistance in the preservation of endangered species.  The first live birth from frozen semen was reported in the dog nearly 50 years ago by Dr. Stephen Seager, a veterinarian who then realized that the technique of semen extraction and preservation followed by insemination could be applied to endangered species.  The first successful application of this technique was used for the Canadian Timber Wolf and research with domestic cats lead to the first semen collections in the cheetah, clouded leopard, snow leopard, and three tiger species.  Semen is collected after short bursts of low electric current are applied through a rectal probe placed near the prostate gland.  This procedure is usually carried out under general anesthesia, essential for use with large and dangerous mammals.  Dr. Seager is a pioneer in the technology development and in extraction and characterization of semen characteristics in over 120 species ranging from small birds to large rare mammals, many of these studied for the first time.

Dr. Seager has done extensive field work in zoos, game parks, and in the wild.  He has studied grizzlies and polar bears, the exotic and extinct in the wild Przewalski horse, the Arabian oryx, and was the first to study the large apes including gorillas, orangutans, and chimpanzees.  He was invited by China to work with Giant Pandas captured in the wild and inseminated them in captivity, a study supported by the World Wildlife Fund.  He was the first to extract semen from the hornbill.

The success with wildlife insemination prompted Dr. Seager to apply this technology to neurologically impaired men in 1984.  As one of the world’s leading experts, he has trained numerous physicians in the use of electroejaculation techniques which has resulted in approximately 40,000 children fathered by men with spinal cord injury or other neurological disorders who otherwise may not have been able to have natural children.

As a urologist, our specialty deals with male infertility and I was keenly aware of Dr. Seager’s work.  It has been my distinct honor to assist him on some of his missions with endangered species including the white rhino, black rhino, lowland gorilla, and the Asiatic Golden Cat, a rare and elusive midsized Southeast Asian wild cat.

It is obvious that the logistics of working with endangered species are of greater magnitude than working with humans and semen extraction from the rhinos illustrates the obstacles faced with such an endeavor.  The white rhino at the Berlin Zoo at age 25 had developed arthritis in his knees making it difficult to impregnate the cows and there was a desire to impregnate an Austrian captive female.  The white or square-lipped rhinoceros is generally regarded the third largest living land animal, with adult males weighing approximately 4500 lbs. The anesthetic range is rather narrow so one walks a fine line between too much anesthesia and a risk of killing this magnificent and very expensive animal or too little anesthesia and being in close proximity of a very dangerous, irritated beast.  Once darted, however, there are anxious moments waiting for the animal to become drowsy enough to approach.  This is important because, like humans, rhinos tend to go lean against the wall when tipsy.  If the animal becomes fully anesthetized in that position, it is impossible to maneuver into position for access.  So, one of the assistants draws the task of running into the cage and getting the attention of the drowsy animal to coax it into the middle of the floor.  It is quite humorous and not a bit unlike a bullfighter getting the bull rhino to stagger toward the middle of the floor.  Then assistants await the final anesthetic effect, ready on both sides with large pillows to cushion the animal as it slides to the floor to protect if from fracturing a leg or other injury.

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After being safely deposited on the ground, the animal is then sprayed with cool water periodically to control temperature while the procedure occurs, first with examination and measurements followed by placement of the probes.  Probes are customized for the animals and Dr. Seager has developed a wide array of these devices, ranging from tiny instruments for small animals to probes that look like a rocket-propelled grenade launcher for the big boys.  Once positioned, the probe is activated to provide a short burst, low amperage electrical stimulus to the area around the prostate where nerves reside that cause the muscular contraction of ejaculation. Several electrical cycles result in ejaculation and successful extraction.  In this case, microscopic examination of the half beaker sample demonstrated a very healthy and viable specimen appropriate for insemination.  The sample was quickly put on ice, packaged, and a team of vets departed for Austria.  Reports of success with insemination means that I am now an uncle to a young rhino!

 

This was the first time in the world that a white rhino had undergone this procedure.  Extraction from the black rhino then proceeded in a similar fashion, and it was the second time in the world for semen extraction from the more critically endangered black rhino.  Though a bit smaller, the black rhino is more aggressive so care must be taken.  In fact, the only time I saw our Zulu tracker nervous on a walk looking for rhinos in Africa was because of the possibility of encountering a black rhino.  White rhinos may hesitate and not charge right away but a black rhino charges without provocation.  Furthermore, white rhinos are grazers and often visible in grasslands whereas the blacks are browsers and hidden in trees and brush making them quite dangerous.  But in the cage they could not appear suddenly and the procedure progressed uneventfully with a similar result of a robust, viable specimen.

 

The lowland gorilla is highly endangered and there are very few wild caught specimens in captivity because of the ban on capture.  So it was with great interest I was asked to assist Dr. Seager in evaluation of one a rare, wild caught young male rescued in Africa after his mother was poached 17 years ago.  These fascinating creatures are truly captivating up close and one gets the feeling that you are being studied instead of the reverse.  The challenge of anesthesia in a large animal is also present here but we were on more familiar ground because of the relative resemblance to human anatomy.  In fact, it was a great thrill for me to intubate the gorilla (insert the breathing tube into the airway) at the time of anesthetic induction.  Respiration is challenging under anesthesia because standard human airway tubes cannot be used as efficiently due to the large diameter of the larynx which allows some air to escape around the tube while the large lung capacity makes listening for breath sounds difficult.  The gorilla also has quite small genitalia relative to its overall size making extraction more challenging, but we were successful.

 

The Asiatic Golden Cat, also known as Temminck’s Golden Cat, is a beautiful animal weighing about 40 pounds that looks a bit like a small cougar.  Elusive and highly endangered because of environmental pressures and encroachment of civilization, few of these cats exist in captivity.  The problem in this issue was that male cats are very aggressive and there is a real possibility that it might kill the female instead of breeding.  Therefore, before tackling the issue of conjugal proximity, it was decided that an evaluation for semen quality would be appropriate to determine whether such a risk to a valuable female should proceed.  In this case, a smaller probe was indicated and after examination, measurements, and stimulation, a very viable and robust specimen was confirmed by microscopic evaluation.  Now the dilemma is how to get the two cats together without a fatal incident.  The vets have decided to house the cats in adjacent cages to acclimate themselves to each other and then to attempt breeding in a year.  Seems like a long time to wait but there are no other suitable options.  Trying to extrapolate that to the human situation, I suspect that arrangement would run the risk of divorce before conception!

I look forward to future opportunities to assist Dr. Seager with his fascinating research and its application to preserving the earth’s endangered species.  He is a true pioneer and I consider myself very lucky to have had these experiences.