FILE: Xizang Autonomous Region, southwest China - July 10, 2025 (CCTV - No access Chinese mainland)
1. Various of newly born cloned yak, breeders taking care of it

FILE: Xizang Autonomous Region, southwest China - Recent (CCTV - No access Chinese mainland)
2. Various of yak running in cowshed; yak running, having fun
3. Yak running, having fun outdoors
4. Various of researchers checking yaks in cowshed
5. Various of yaks in cowshed

The world's first cloned yak turned one month old on Sunday in southwest China's Xizang Autonomous Region, marking a major breakthrough in the breeding of the species.

The jet-black calf was born via caesarean section on July 10 at a yak breeding base in Damxung County.

It is named "Namtso No. 1," after the Namtso Lake, the world's highest saltwater lake with a lake-surface elevation of over 4,700 meters.

It weighted 16.75 kg at birth and has nearly doubled its weight to 31.95 kg after a month of exclusive breastfeeding, gaining around 0.5 kg per day, according to breeders.

Namtso No. 1 was cloned from donor cells taken from a "seed yak" selected by a research team from Zhejiang University from over 8,000 domesticated yaks.

The donor animal was prized for its large size, rapid growth and strong resilience to harsh environments.

The scientists used a combination of whole-genome selection and somatic cell cloning technologies to produce the cloned yak.

Yaks, endemic to the Qinghai-Xizang Plateau, are both an economic lifeline for herders and a crucial part of the plateau's fragile ecosystem.

The project began in July 2023 as a joint initiative by Zhejiang University, the Damxung County government and the region's Institute of Plateau Biology, against the backdrop of a sharp decline in the genetic quality of Xizang's yak population over the past three decades.

Smaller body sizes, reduced weights, loss of genetic diversity, and long production cycles ranging from five to eight years have hindered the industry's development.