How historically accurate is the claim that Buchenwald commandant Karl Koch fed prisoners to the camp’s zoo animals?

I came across a citation in a book that mentions Karl Koch’s zoo at Buchenwald, allegedly including instances where prisoners were fed to the animals (bears, in particular). The source given is:
Barth, Boris: “Tiere und Rasse: Menschenzucht und Eugenik.” In: Tiere und Geschichte: Konturen einer Animate History, ed. Gesine Krüger, Aline Steinbrecher, Clemens Wischermann. Stuttgart: Franz Steiner Verlag, 2014, p. 201.
I haven’t been able to access the chapter itself (no open-access copy available, and I’d rather not buy the whole volume for a single citation), so I can’t verify what’s actually claimed on that page.