A feeder nurses a white tiger at a nursery house in the Xixiakou wildlife protection area in Weihai, east China`s Shandong Province, May 21, 2011. The eight-year-old white tiger mother "Lili" gave birth Friday to two white female tigers and two snowwhite female tigers, belonging to a relatively rare species. These four tiger cubs now have to get fed from a "dog mother", because the tiger mother, who has already given birth to another quadruplets of three snowwhite tigers and one white tiger last September, refuses to feed her kids. (Xinhua/Yu Qibo)

The newly-born quadruplets of tiger cubs get breast-fed from a dog mother at a nursery house in the Xixiakou wildlife protection area in Weihai, east China`s Shandong Province, May 21, 2011. The eight-year-old white tiger mother "Lili" gave birth Friday to two white female tigers and two snowwhite female tigers, belonging to a relatively rare species. These four tiger cubs now have to get fed from a "dog mother", because the tiger mother, who has already given birth to another quadruplets of three snowwhite tigers and one white tiger last September, refuses to feed her kids. (Xinhua/Yu Qibo)

A feeder shows the newly-born quadruplets of tiger cubs at a nursery house in the Xixiakou wildlife protection area in Weihai, east China`s Shandong Province, May 20, 2011. The eight-year-old white tiger mother "Lili" gave birth Friday to two white female tigers and two snowwhite female tigers, belonging to a relatively rare species. These four tiger cubs now have to get fed from a "dog mother", because the tiger mother, who has already given birth to another quadruplets of three snowwhite tigers and one white tiger last September, refuses to feed her kids. (Xinhua/Yu Qibo)

Tiger cubs yawn at a nursery house in the Xixiakou wildlife protection area in Weihai, east China`s Shandong Province, May 21, 2011. The eight-year-old white tiger mother "Lili" gave birth Friday to two white female tigers and two snowwhite female tigers, belonging to a relatively rare species. These four tiger cubs now have to get fed from a "dog mother", because the tiger mother, who has already given birth to another quadruplets of three snowwhite tigers and one white tiger last September, refuses to feed her kids. (Xinhua/Yu Qibo)