Abstract
Hoof overgrowth and associated lameness are common health concerns for giraffes at many zoos. A study of lateral and lateral oblique radiographs from 22 reticulated giraffes (Giraffa camelopardalis reticulata) in human care showed a high prevalence of hoof overgrowth, pedal osteitis, osteoarthritis, sesamoid bone cysts, distal phalangeal bone (P3) rotation, and P3 fractures before the herd was trained for voluntary hoof trims.1 To better understand how foot health compares between zoo and free-ranging giraffes, the feet of 28 Nubian giraffes (Giraffa camelopardalis camelopardalis) were studied during a translocation in Uganda (August 2017). While most animals in this study were relatively young (estimated 1–6 years old) compared with the study involving zoo giraffes (0.5–32 years old), multiple differences in hoof shape and radiographs were identified even when comparing young animals. Free-ranging giraffes had more hoof capsule symmetry, the solar surface was relatively concave, and hoof overgrowth usually only involved the toe tip. Lateral oblique radiographs of the feet of free-ranging giraffes showed that pedal osteitis and sesamoid bone cysts were relatively uncommon (3/28 giraffes with osteitis, 1/28 giraffes with sesamoid cysts) and that no giraffe had osteoarthritis of the distal interphalangeal joint, P3 rotation, or P3 fractures. Additionally, the radiographs demonstrated that the sole plane runs parallel to the distal surface of P3, which could serve as a guide when trimming the feet of zoo giraffes. This study shows that there are differences in the foot shape and health of zoo and free-ranging giraffes, and that husbandry modifications and regular hoof trims can result in healthier feet of giraffes in human care.
Acknowledgments
Thanks to our 236 crowdfunding supporters at Experiment.com who helped with travel costs and supplies for the wild hoof x-ray study, and to VetRocket for loaning us digital radiography equipment for the field research in Uganda. Thanks also to the dedicated team of vets and rangers with the Uganda Wildlife Authority for leading the Operation Twiga II giraffe translocations, to the Giraffe Conservation Foundation for helping coordinate this research, and to the Metzger Foundation for funding the translocation.
Literature Cited
1. Dadone L, Han S, Foxworth S, Klaphake E, Johnston M, Barrett M. Diagnosis and management of pedal osteitis and pedal fractures for a large herd of reticulated giraffes (Giraffa camelopardalis reticulata). In: Proc Am Assoc Zoo Vet. 2014:104.