

Two white tiger cubs, Rico and Kico, born on March 8 at the Serengeti Safari Park in Hodenhagen, Germany, are seen during a photocall on April 21. The cubs were raised with bottled milk by keeper Regina Hamza. Christian Charisius/Reuters
Keeper Regina Hamza feeds Rico and Kico from bottles during a press conference at the Serengeti Park in Hodenhagen, Germany, on April 21. Focke Strangmann/AP
One of the white tiger cubs walks around during a photocall on April 21. Christian Charisius/Reuters
One of the 6-week-old white tiger cubs is examined by veterinarian Christiana Hensel (l.) and zoologist Michael Broeer during a press conference on April 21. Focke Strangmann/AP
One of the white tiger cubs hisses during a photocall at Serengeti Safari Park in Hodenhagen, Germany. Christian Carisius/Reuters
One of the white tiger cubs, Rick and Kico, hisses during a photocall on April 21 at the Serengeti Safari Park. Christian Charisius/Reuters
A white tiger cub is seen relaxing on hay during a press conference on April 21. Focke Strangmann/AP
Surrogate mother, Regina Hamza, rubs her nose with one of the two white tiger cubs she has been bottle feeding at the Serengeti Safari Park on April 21. Focke Strangmann/AP
Hameed Hamza, the two white tiger cubs' surrogate father, holds one of them during a press conference at Serengeti Safari Park on April 21. Focke Strangmann/AP
One of the white tiger cubs, Rico or Kico, at the Serengeti Safari Park sits on hay on April 21 during a press conference. Christian Charisius/Reuters