News and Stories

You may remember reading about the Lindner Center for Conservation and Research of Endangered Wildlife (CREW)’s involvement as a founding member of the American Institute of Rhino Science (AIRS) over the past several years. AIRS was a 3-year IMLS funded project that explored four pillars of rhino health: physical fitness, reproduction, wellbeing, and iron overload disorder (IOD). The goal? To improve and support management practices for rhinos in zoos across the world.

Here is an update on what we’ve learned so far:

Iron overload disorder is a disease that affects Sumatran and black rhino species. Iron builds up (overloads) in the liver causing damage and eventually death. There is currently no way to diagnose this disease on a live animal. This led to the big question driving CREW’s IOD research: could scientists find a less invasive way to measure iron levels in rhinos? Knowing it is possible to measure other things through the rhino’s hair, CREW scientists wondered, could rhino horn, which is made of the same thing as hair, keratin, provide a useful alternative to traditional sampling methods? Preliminary results showed promise, but while iron levels can be measured in the horn, they found that horn iron cannot be used as a proxy to measure internal iron levels.

Within the reproductive pillar, CREW scientists asked: is there a way to standardize semen evaluation? The answer is yes. They developed and validated a rhino-specific app on the iSperm platform. This app and tool make semen analysis faster and easier while helping scientists evaluate samples more consistently.

For the females, scientists explored factors that may be causing reproductive dysfunction. Although researchers expected that season or vitamin D levels may correlate to reproductive dysfunction, they found no correlation between acyclicity (the absense of reproductive cycling) and either season or vitamin D levels. They also ruled out a link between acyclicity and elevated prolactin, a hormone associated with lactation, in serum samples. However, prolactin may still prove useful as a potential indicator of pregnancy!

Another interesting finding emerged when scientists examined the social environment. A study found a positive correlation between reproductive activity and the presence of a mature male near females, highlighting a potential relationship between social factors and female reproductive activity.

Overall CREW has published 6 of papers from this project, with more coming!

While the grant funded portion of AIRS, dubbed AIRS 1.0, was “completed” in 2024, the work is far from over! The CREW Rhino team and collaborators are pushing towards AIRS 1.5 which will further explore rhino reproduction, wellbeing, and IOD.