Abstract

Wild rhinoceros populations are currently threatened due to poaching and habitat loss, and captive populations are not self-sustaining.^5,11,12 Therefore, efforts toward maximizing captive breeding efforts are critically important. While there have been great increases in knowledge of rhinoceros reproductive physiology and breeding management, there is still a lack of understanding regarding what are considered normal parameters during parturition.^7,9,10 We reviewed data regarding parturition of two rhinoceros species (southern white rhinoceros [SWR] and greater one-horned rhinoceros [GOH]) from videos, medical records, and literature of documented birthing events.^1,4,8 Using equine parturition parameters as a model for comparison, we compiled the following data on two species of rhinoceros: signs of impending parturition, duration of the three phases of parturition, and normal calving presentation.^2,3,6 Preliminary data from 11 animals (seven SWR, four GOH) and 16 births comparing calf presentation and viability documented five stillbirths (four posterior and one unknown presentation) and 11 live births (six anterior, one posterior, and four unknown presentations). Ongoing data collection will lead to a more robust data set and will strive to include black rhinoceros (Diceros bicornis). The authors would like to stress the importance of investing in the monitoring of parturition, as detailed documentation is a necessary tool in determining normal parameters. The data presented in this review are intended to aid facilities with rhinoceros breeding programs and to provide prospective standardization of parturition observation parameters.

Acknowledgments

The authors thank the San Diego Zoo Safari Park rhinoceros keeper, supervisor, and curatorial staff for their support in this project and their dedicated care for our rhino collection. We also thank Jane Kennedy, retired San Diego Zoo Safari Park keeper, for her passion and commitment to learning about rhino parturition.

Literature Cited

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