Where else in the world, "South China Tiger"?

Population crisis

Experts explain the South China Tiger gene genealogy captive South China Tiger also faced degradation crisis

www.thebeijingnews.com · 2007-10-21 0: 11: 29 ·

Source: Beijing News

Quantity

The world is only 68 only

In 1995, the country has 18 feeding units of South China tiger in Suzhou to convene a General Assembly, in the face of the current status of the South China Tiger, saved explicitly indicated to the international pedigree as a standard, to establish pedigree of South China tigers in captivity to the South China Tiger better protected.

Since then, Yin Yu in became an "administrator," South China Tiger family tree. "Establishing a genealogy, you can clearly understand these relationships of a tiger, or Tiger's scientific basis for mating with reliable. " The establishment of the South China Tiger pedigree is on the existing number of South China Tiger. By 1995, China South China Tiger, from agencies of captive Tiger breeding, transfer of records to look for clues.

The current South China Tiger genealogy show in captivity, the South China Tiger began in 1955.

At that time, it was in Sichuan capture a female South China Tiger, the name "abruptly" (MENGZI), the number is "1". The pedigree of restored "abruptly" in China's transfer history: it was shipped to Hebei, temporarily breed over time, transfer to Shanghai for 15 years in captivity, 1970 and was transported to Hefei Xiao Yao-Zoo, the same year died.

Recently, Yin Yu-just log on to finish in the South China Tiger pedigree in 2007 data, because it did not go through the South China Tiger feeding unit of the Joint Assembly recognized, so you cannot publish the most current data.

From 2006 the South China Tiger pedigree, we can see, from 1955-2006 51 years, China has 40 large and medium cities feeding of Zoo or Park just over 385 (pedigree login number of individuals) South China Tiger. One of the male body, only 200 females only 153, and another 32 only because cub that was just a birth, death, and so did not record their gender. While in the South China Tiger only 385, currently living 68 only.

"Through the South China Tiger pedigree, we can also be traced to the original constructive.

" Yin Yu said. In fact, since 1955, 1967 in 12 years, China's total capture from the wild is only the male body, 6 12 females in South China tigers put into captive populations. "However, these tigers in real production have descendants of only 6 only. " Yin Yu, stated that the existing South China tiger population in captivity is 1958 captured 6 wild tiger constructive. Their pedigree of serial number: "8", "26" (male) and "3" and "6" and "7" and "12" (female) Fourth, the fifth generation. They are close relatives, some brothers and sisters, some between reproduction and generational inbreeding.

The Zoo, for example.

Currently, the Zoo has only one on the South China Tiger. "This is a pair of old tiger, the past two years, we have no propagation. " The South China Tiger's pedigree, 227 and 229 is.

Yin Yu in traces the two South China Tiger's family history.

227 parents is 147, 157. And 147 of the parents is 73, 112, the Tiger is half siblings, their mothers are 27, father is 26 and 29. And 27, 29, a pair of brothers and sister is, their mothers are 3, father is 8 and 26 respectively. Therefore, the only number 227 of the South China Tiger is initially constructive only 6 and 26 and 3 generations, and as the mother of 73 and 112 are 27 112 73 and in fact already be different with the mother and father inbreeding. More troublesome is that the parents are 157 73, 147 and 112, 157 is mating with parent the same mother.

Look at the number 229 of South China Tiger.

It's parents are 111 and 69. One of the parents is 111, 26 and 27.

While 27 of parents is 8 and 3.

While the parents are 69 26 and 3. This complex relationship in a close relative who is 229, "mother" 3 gave birth to a daughter, "27", and daughter 27 and mother are both 3 and 26 mating, gave birth to 111 and 69.

Speaking of this complex genealogy, Yin Yu also indicates that it is forced to, because so far the only initial colonization that 6 wild South China Tiger, then there would be no new constructive involvement of practitioners, which this group is between the South China Tiger with parents, parents and relatives.

Recession

Captive South China Tiger also fast disappearing

Because of inbreeding, 6 constructive ' gene diversity has been lost.

According to projections, in 1963 to 1977, 14 years, the South China tiger population about also retains its 85% of the genetic diversity, subsequently began to decline.

With the establishment of captive stocks and other left no offspring older individual survival of die-offs, 1990 gene diversity begins to significantly reduce the existing captive is preserved by gene diversity is less than 75%.

And captive average inbreeding coefficient has gradually increased during the same period.

Currently, the South China tiger populations in captivity inbreeding coefficient maximum has been reached 0.4921. This number mean? Yin Yu in explained that this value is equivalent 0.25 near brothers and sisters or between mating between parents and children, and the reproduction of the level is very very 0.4921Kissed. "Rare to have heterogeneous individuals move into wild populations to improve blood relationship, inbreeding and always will be inevitable, and will become more and more serious. " It seems the Yin Yu, in the South China tiger population genetic diversity will continue to decrease, inbreeding coefficient will also increase, these two trends are parallel.

In addition, the South

China Tiger also face population gradually decline.

Yin Yu, in 1956-1986-30 years, the captive population growth more obvious to the average annual growth rate of 13.7%.

While the 1985 and 1995 the population growth rate close to the long term, with 0, Shanghai and Suzhou two Zoo breeding records.

Led captive populations of the South China Tiger because of the reduction in breeding in captivity fewer South China Tiger.

The fertile South China Tiger, although the male body has 21 only, but the female body in only 9 only, the sex ratio was unreasonable.

In fact, existing fertile male Tiger, only 4 only mate, only 2 have survival of future generations; fertile female Tiger, only 5 only litter, of which only 3 only the survival of future generations. Succeed in the survival of future generations of bred South China tiger in less than 10% of the population in captivity. In the South China Tiger artificial propagation of 38 years, only Guiyang, Shanghai, Guangdong, Chongqing, Suzhou and Fuzhou, Nanchang, seven of the 18 units farmed only the male body, 23 only female body successfully bred out of the survival of future generations.

"In captivity for breeding success rate is very low.

" Should not be overlooked that, due to significant loss of genetic diversity, not only in new descendants born larval mortality is high, and often appear congenital Dysplasia, institutional weakness, hereditary diseases wait for negative consequences, such a sharp reduction in population, the entire population showed growth momentum.

"We hope to have the new constructive to join in.

" Yin Yu did not direct evaluation of this shanxilinyeting wild South China Tiger photos. South China Tiger as a captive of the staff, he is just particularly want wild South China Tiger really exists.

Gene

It is wild in the South China Tiger?

According to the book of re

cords, the South China Tiger has been widely distributed in East China, central China, South China, Southwest, and even Shaanxi, Gansu province, Henan province, jinnan, quantity should be more than 10 million.

In the middle of last century, China South China tiger numbers also maintained at around 4000 only.

But in the subsequent decades, the number of South China Tiger.

In 1990, the Board of forestry and wildlife protection society of cooperation on the South China Tiger for a special investigation, concluded that wild South China Tiger only 20 to 30 only. In 2001, the State Forestry Administration in cooperation with foreign agencies on the South China Tiger survey is of the view that the possibility of the existence of the wild population is not very big. In expert eyes, wild South China Tiger has been regarded as the "functional". Although in recent years there are still some areas report a South China Tiger wounding and discover South China Tiger trail and other messages, but these messages are not able to get the authoritative Department confirmed.

From here, the captive Tiger has become the hope of saving the South China Tiger.

In General, on the individual conduct of captive and wild training, has become an important recovery field populations. South China Tiger is no exception. Researchers hope to recover captive populations of wild behavior training. Of course for field training, the protection of the wild South China Tiger Habitat, restoring damaged by human activity, of ecosystems is also an important issue.

However, imagine how far better than reality.

Currently, the South China Tiger should be can't be wild of controversial in the scientific community. Since the country's South China tigers in zoos are mostly is the fifth generation of individuals in captivity, have lost the ability to live independently in the field, especially in areas such as predation and missing key behavior. The capacity of access to non-a-day.

"The key is that these captive of the South China Tiger really be considered South China tigers are problematic.

" A bit reluctant to disclose names of Zoologists.

In fact, foreign scholars on captive South China Tiger origin as early as the purity of the end of 2004.

United States National Cancer Institute, stated Dr. King had engaged in the world of the Tiger system geography, population structure and genetic study of the origin. In December 2004, in his famous "public library of Science Biology · (PLoSBiology) magazine published a paper, discusses global Zoo captive Tigers DNA genetic analysis.

Related experiments by one from United States, Singapore, Malaysia international research group.

Analysis found that, in China many of the South China Tiger Zoo is not a true South China Tiger — — the South China tiger in genetic on both branches.

The paper noted that Chongqing Zoo captive of the South China Tiger, their genes and other subspecies of Tiger significant differences compared to that, it is not possible to represent the real South China Tiger.

But Suzhou Zoo keeping the South China Tiger with a large number of Indo-Tiger genes, almost the same with the Indo-Tiger.

This conclusion, existence of captive South China Tiger genes recession and with other subspecies of hybrid, which is characteristic of the South China Tiger gradually lose. The animal experts stressed that: "If these captive in the South China Tiger really the Indochinese Tiger, then genetic so-called wild is also required all need make a question mark, because now the wild Indochinese Tigers there are many individual survival. " For this study, Zhang Jin-Suk also stated that, while the research team in China acquisitionSouth China Tiger specimens. But essentially China South China Tiger is representative. From the results of the analysis of the molecular biology of the South China Tiger's captive geographic origin of doubt, where a lot of possibilities is the Indo-Chinese tiger wide distribution, which widely penetrated into China's southern region, but before the so-called wild South China tigers have the Indochinese Tiger gene. Or previous feeding mistakenly Indo Tiger as the South China Tiger.

"Protecting the South China Tiger is a subspecies of tiger conservation.

" Zhang Jin-Suk pointed out that, although the comparison is clearly divided into Tiger several geographical subspecies, but several subspecies of genetic polymorphisms in between. In other words, several subspecies of Tiger and there is no significant difference. In the current domestic funds are limited, and its focus on the wild South China Tiger body, strengthen the other Tigers have equally important ecological functions of large cats protection, such as Leopard, Snow Leopard, the clouded leopard, Lynx, etc.

Reporter Li Jian-

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