North American Crane Working Group


Date of this Version


Document Type



Proceedings of the North American Crane Workshop 13: 32


2014 North American Crane Working Group. Used by permission. Proceedings may include articles not presented at Workshop.


Osteoarthritis is a problem that threatens the reproductive capabilities of captive populations of endangered cranes. In our pilot study, we used 5 cranes with a history of unilateral, chronic tarsal pathology in a cross-over design to gauge the effects of the primary ingredient (NEM®, ESM Technologies LLC, Carthage, MO) of the nutraceutical Steadfast® (Novus Nutrition Brands, LLC, St. Charles, MO). We evaluated the ingredient for acceptance, safety, and short-term efficacy. To evaluate efficacy, we collected goniometric measures to determine range of motion in each tarsal joint before and after a 5-week experimental period where NEM® was offered in pelleted feed. We also determined time spent in locomotion from estimates of activity once per week. The ingredient was determined to be both acceptable as offered and apparently was safe for the cranes. There were no significant changes in the birds’ weights or body condition scores during any period of the trial. There was a significant increase in overall tarsal flexion measurements in the 5 birds’ affected legs (P = 0.04), and 1 bird showed +14 degrees of improvement in flexion. No changes were seen in measures of tarsal extension or in either measure in unaffected legs. The behavioral data was inconclusive due to the small sample size and large variation in the weekly estimates within individuals. Though there was evidence of increased joint mobility in all birds in this small pilot study, further study is needed to determine if NEM® is efficacious for managing osteoarthritis in cranes.