Our traveling rhinoceros specialist, Dr. Nan Schaffer, visited
the North Carolina Zoo in Asheboro and collected semen from a pair
of southern white rhinos.
Successfully collecting a large quantity of semen from a white
rhino is no easy task. The procedure requires general anesthesia,
which makes it a complicated and risky endeavor, because white rhinos
do not respond well to anesthesia. Dr. Schaffer's methodology improved
their response. With careful maintenance of the rhinoceroses under
anesthesia by the zoo vets and the new use of ultrasound to monitor
the procedure by Dr. Schaffer, a victory was won.
With the successful outcome, Dr. Schaffer was able to freeze the
semen for analysis. Semen from a rhinoceros usually does not freeze
well, meaning that once it is frozen, the sperm's motility, or movement,
may not be regained once thawed. Water in the sperm cell is replaced
by a cryogenic preservative, since it can rupture the cell. Water
returns when the cell is thawed but the motility may not return
to its pre-freeze level. These methods still need to be improved.
SOS Rhino currently supports a research project headed by an Austrian
and a German--veterinary scientists Schwarzenberger and Hildebrandt.
This project is further defining the ultrasound monitoring technique
and semen collection procedure. Schwarzenberger and Hildebrandt
are conducting an analysis of fertility of rhinos and attempting
an artificial insemination of a rhino. Learning more about the rhino's
reproductive system may help bring the endangered animal back from
the brink of extinction.
Schaffer discussed the method that meant success in North Carolina
and its possible repercussions for the propagation of the species
at the International Elephant and Rhino Research Symposium, which
takes place at the Vienna Zoo, June 7--11, 2001