AboutZoos, Since 2008


Zoo diets may be harm­ing white rhinos

pub­lished 25 March 2012 | mod­i­fied 07 April 2012

South­ern white rhi­noc­eros pop­u­la­tions in zoos have been show­ing severely reduced repro­duc­tiv­ity and it may be down to their diet, researchers of San Diego Zoo say. They may have deter­mined why the rhino pop­u­la­tions in managed-​care facil­i­ties are declin­ing: phyto-​estrogens in their diet might be con­tribut­ing to repro­duc­tive fail­ure in the females.

The south­ern white rhi­noc­eros (Cer­a­totherium simum ssp. simum) is on the IUCN Red List of Threat­ened Species™ as “near-​threatened”. Wild pop­u­la­tions face poach­ing and sport hunt­ing, but cap­tive pop­u­la­tions have been declin­ing because of repro­duc­tive issues in the females includ­ing cys­tic endome­trial hyper­pla­sia; cer­vi­cal, ovar­ian, and uter­ine can­cers; and ovar­ian cysts, the Zoo­log­i­cal Soci­ety of San Diego reported.

The Zoo researchers say they believe the diets of the cap­tive pop­u­la­tion is a con­cern and that phyto-​estrogens such as isoflavi­noids found in the alfalfa and soy they eat acti­vate their estro­gen recep­tors more than those of the greater one-​horned rhi­noc­eros, another cap­tive pop­u­la­tion that receives a sim­i­lar diet but has bet­ter repro­duc­tive suc­cess. The researchers com­pared pop­u­la­tions that are doing well with pop­u­la­tions whose repro­duc­tiv­ity is plac­ing them at risk, and said diet is a key dif­fer­ence between the two.

Under­stand­ing why the cap­tive white rhi­noc­eros pop­u­la­tion has been dwin­dling for decades is an impor­tant part of pro­tect­ing the future of this species

white rhinoceros

Our work is the first step toward deter­min­ing if phy­toe­stro­gens are involved in this phe­nom­e­non and whether we need to re-​evaluate cap­tive white rhino diets,” Christo­pher Tubbs, researcher with the San Diego Zoo Insti­tute for Con­ser­va­tion Research, said.

The above news item is reprinted from mate­ri­als avail­able at upi​.com. Orig­i­nal text may be edited for con­tent and length.

(Source: UPI​.com, 21.03.2012)

UN Biodiversity decade
WWF Stop Wildlife Crime
Fight for Flight campaign
End Ivory-funded Terrorism
Support Rewilding Europe
NASA State of Flux

Goal: 7000 tigers in the wild

Tiger range countries map

Tiger map” (CC BY 2.5) by Sander­son et al., 2006.

about zoos and their mis­sion regard­ing breed­ing endan­gered species, nature con­ser­va­tion, bio­di­ver­sity and edu­ca­tion, which of course relates to the evo­lu­tion of species.
Fol­low me on: