Semen characteristics of Bornean sun bear (Helarctos malayanus euryspilus)

Boon, Nie Yeoh and Zainal Zahari Zainuddin and Wen, Mark Han Hiew and Siti Aisyah Sidik and Siew, Te Wong and Rosa Sipangkui and Abdul Hamid Ahmad (2022) Semen characteristics of Bornean sun bear (Helarctos malayanus euryspilus). Theriogenology Wild, 1. pp. 1-7. ISSN 2773-093X

[img] Text

Download (43kB)
[img] Text
Full text.pdf
Restricted to Registered users only

Download (2MB) | Request a copy


The Bornean sun bear (Helarctos malayanus euryspilus), endemic to Borneo Island, is the subspecies of the Malayan sun bear. The species is at risk, not just because of anthropogenic threats, but also slow reproduction in the wild. In captivity, due to poor reproductive performance, assisted reproductive technology is deemed a fundamental tool to propagate the depleting numbers of the Bornean sun bear. This is a pioneer study that presents the semen characteristics of the Bornean sun bear via conventional semen evaluation methods. Forty-two semen samples from ten sun bears were collected via electroejaculation and evaluated. The electro ejaculator probe (2.5 cm in diameter and 7.0 cm in length) was inserted rectally and positioned dorsal to the prostate gland. The optimum voltage used to obtain semen differed with each individual, but all showed hindlegs contraction and penile erection before ejaculation. The average combined testes volume in the Bornean sun bear was 23.37 ± 5.09 cm³. The mean semen volume was 617.30 µL, with sperm concentration of 1034.40 × 10⁶ sperm/mL and pH 7.79. Sperm viability was 80.19% with a general motility of 79.13% and progressive movement of 70.20%. There were high sperm abnormalities at 70.67%. Sun bear sperm length was 61.28 ± 2.46 µm and consisted of an oval head, midpiece, and tail. From this study, good semen donors were identified from the captive Bornean sun bear population in Sabah, Malaysia. The fresh semen baseline data established in this study will provide crucial reference for assisted reproduction programs in the Bornean sun bear.

Item Type: Article
Keyword: Bornean sun bear , Electroejaculation , Semen , Sperm , Assisted reproductive technology
Subjects: Q Science > QL Zoology > QL1-991 Zoology > QL1-355 General Including geographical distribution
Department: INSTITUTE > Institute for Tropical Biology and Conservation
Date Deposited: 27 Sep 2022 11:52
Last Modified: 27 Sep 2022 11:52

Actions (login required)

View Item View Item