http://nationalzoo.si.edu/conservationandscience/spotlightonscience/bushmitchell.cfm
You'll like the above article but I think you will find this very useful from the bottom of the above page too
"If you are interested in the history and scientific details of giraffe anesthesia, Bush has published an article on the topic in an Internet journal.
To find it, go to
http://www.ivis.org/. Free registration and password are required. Enter the word “giraffe” in the site’s search engine to find “The Art and Science of Giraffe (Giraffa camelopardalis) Immobilization/Anesthesia.”
Ivis looks to me to be the area you want to go to do your research. I would think an adaptation of slings used for surgeries on horses or for recovery after surgery might work for you. So researching the horse apparatus might prove valuable for zoo animal work.
Hope this helps you!
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