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bioRxiv · 10.1101/2025.05.21.655307

A novel molecular sexing method for Greater One-horned Rhinoceros (Rhinoceros unicornis) for reliable demographic assessments

Kumar, S.·Ghosh, T.·Sharma, A.·Mondol, S.
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Abstract

Accurate assessment of demographic parameters is crucial for conserving endangered species. The Greater One-horned Rhinoceros (Rhinoceros unicornis), a sexually monomorphic species, lacks a validated molecular sexing protocol for diverse biological samples. This study established a multi-marker molecular sexing protocol using blood, tissue, horn, and dung samples from all wild populations in India. The optimized multiplex strategy that involves three sex-linked markers: ZF, AMESC, and TSRY, enabled simultaneous amplification of X-and Y-chromosome-specific fragments in degraded samples. Testing with 286 individual rhino samples from seven parks (5 blood, 180 tissue, seven horn, and 94 dung) led to a [~]92% (195 M: 69 F) success rate. Overall, this approach validates a molecular sexing protocol with increased reliability and fewer amplification failures, facilitating large-scale demographic studies. Future research should utilize this method to examine the sex ratio of all existing Indian rhino populations across their range, ensuring their future persistence and management.

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Kumar, S., Ghosh, T., Sharma, A., Mondol, S.. 2025-05-26. A novel molecular sexing method for Greater One-horned Rhinoceros (Rhinoceros unicornis) for reliable demographic assessments. https://doi.org/10.1101/2025.05.21.655307

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