The Wuzhishan is a Chinese

breed A breed is a specific group of breedable domestic animals having homogeneous appearance (phenotype), homogeneous behavior, and/or other characteristics that distinguish it from other organisms of the same species. In literature, there exist seve ...

of small

domestic pig The pig (''Sus domesticus''), also called swine (: swine) or hog, is an omnivorous, domesticated, even-toed, hoofed mammal. It is named the domestic pig when distinguishing it from other members of the genus '' Sus''. Some authorities cons ...

from the Wuzhishan mountains of

Hainan Island Hainan is an island province and the southernmost province of China. It consists of the eponymous Hainan Island and various smaller islands in the South China Sea under the province's administration. The name literally means "South of the Sea ...

, off the south coast of China. It was formerly numerous in the island, but in the later twentieth century numbers fell heavily as a consequence of indiscriminate

cross-breed A crossbreed is an organism with purebred parents of two different breeds, varieties, or populations. A domestic animal of unknown ancestry, where the breed status of only one parent or grandparent is known, may also be called a crossbreed though ...

ing with pigs of faster-growing breeds. It was listed in 1991 as being at risk of extinction, and in 2000 was officially identified as one of nineteen pig breeds most in need of conservation. Other names for it are the Shan and the Laoshu – which means 'mouse'.

History

The Wuzhishan is a traditional breed of the Wuzhishan mountains of

, off the south coast of China, and was formerly numerous in the island, with an estimated total population in the 1960s of some . Later in the twentieth century, pigs of faster-growing breeds were brought to Hainan from the mainland; indiscriminate

cross-breeding A crossbreed is an organism with purebred parents of two different breeds, varieties, or populations. A domestic animal of unknown ancestry, where the breed status of only one parent or grandparent is known, may also be called a crossbreed though ...

with these led to a rapid decline in numbers of the original stock to no more than a few hundreds, and by 1991 it was considered to be at risk of

extinction Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

. In 2000 it was among the nineteen pigs on a government list of breeds with the highest priority for conservation. A conservation herd at the Institute of Animal Science of the

Chinese Academy of Agricultural Sciences The Chinese Academy of Agricultural Sciences (short CAAS, ) is the National academy, Chinese national agricultural scientific research organization. It was established in 1957 in Beijing and oversees 45 institutes. Thirty-six are direct affiliate ...

in Beijing, established in 1989 from a nucleus of three of the pigs, had by 2004 had grown to some two hundred head. Another herd was established in Hainan by the Academy of Agricultural Sciences in the 1990s, and also grew to about two hundred head.

Characteristics

It is a small pig, with a weight for sows of some , height at the

withers Withers are the ridge between the shoulder blades of an animal, typically a quadruped. In many species, this ridge is the tallest point of the body. In horses and dogs, it is the standard place to measure the animal's height. In contrast, catt ...

of , and body length in the range . The pigs are black with white underparts – the belly, the inner sides of the legs and the feet. The Wuzhishan pig is mainly used to study the human

circulatory system In vertebrates, the circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the body. It includes the cardiovascular system, or vascular system, that consists of the heart ...

due to the similarities between pig and human

organs In a multicellular organism, an organ is a collection of tissues joined in a structural unit to serve a common function. In the hierarchy of life, an organ lies between tissue and an organ system. Tissues are formed from same type cells to a ...

Genetic research

The full

genome sequence A genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding genes, other functional regions of the genome such as ...

and analysis were completed by BGI Group in 2012; the breed was successfully identified in early 2013. The

intellectual property rights Intellectual property (IP) is a category of property that includes intangible creations of the human intellect. There are many types of intellectual property, and some countries recognize more than others. The best-known types are patents, co ...

for the breed are protected by both Chinese and American patents. On May 18 2015, the

announced that its Institute of Animal Science agreed to transfer all breeding research to Beijing Grand Life Science & Technology Co., Ltd., which had the sole rights to breed and sell Wuzhishan pigs for commercial purposes. Multiple Chinese research institutions, medical schools, hospitals, and enterprises conduct research around Wuzhishan pigs to establish their suitability as research models. Research on future

life science Life, also known as biota, refers to matter that has biological processes, such as signaling and self-sustaining processes. It is defined descriptively by the capacity for homeostasis, organisation, metabolism, growth, adaptation, respon ...

and medical applications of the pigs also began to take place, to which the initial results include the injection of

embryo An embryo ( ) is the initial stage of development for a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sp ...

nic

germ cell A germ cell is any cell that gives rise to the gametes of an organism that reproduces sexually. In many animals, the germ cells originate in the primitive streak and migrate via the gut of an embryo to the developing gonads. There, they unde ...

s into

blastocysts The blastocyst is a structure formed in the early embryonic development of mammals. It possesses an inner cell mass (ICM) also known as the ''embryoblast'' which subsequently forms the embryo, and an outer layer of trophoblast cells called the ...

, along with

islet An islet ( ) is generally a small island. Definitions vary, and are not precise, but some suggest that an islet is a very small, often unnamed, island with little or no vegetation to support human habitation. It may be made of rock, sand and/ ...

isolation and purification. On June 23, 2017, the Academy of Military Medical Sciences and Grand Life Science declared that the PERV-pol gene-deficient Wuzhishan pig had been identified and verified by systematic

virology Virology is the Scientific method, scientific study of biological viruses. It is a subfield of microbiology that focuses on their detection, structure, classification and evolution, their methods of infection and exploitation of host (biology), ...

methods and whole genome sequencing. Grand Life had succeeded in reproducing F0/F1 PERV-noninfectious Wuzhishan pigs that became available for advanced biomedical research purposes.中国实验动物信息网，http://www.lascn.net/Item/28132.aspx This included a series of studies under the 2017-2020 National Primary Research Programs on bio-material development and tissue-organ repair.

References

{{reflist, refs= Wuzhishan
''Animal Genetics Training Resource''. Nairobi, Kenya: International Livestock Research Institute. Accessed February 2025. Valerie Porter, Lawrence Alderson, Stephen J.G. Hall, D. Phillip Sponenberg (2016)
''Mason's World Encyclopedia of Livestock Breeds and Breeding''
(sixth edition). Wallingford: CABI. {{isbn, 9781780647944. Breed data sheet: Wuzhishan / China (Pig)
Domestic Animal Diversity Information System of the Food and Agriculture Organization of the United Nations. Accessed January 2025. Pig breeds originating in China Pig breeds