BERLIN (AP) — They're still tiny, but the white lion cubs at the Magdeburg zoo in eastern Germany are putting on weight fast.

The cubs — three males and one female — took turns on the scales Friday. The news agency dpa reported that the male cubs weighed in at an average of 6.5 kilograms (14.3 pounds) each, while their sister was a kilogram lighter.

The cubs weighed only 1.5 kilograms (3.3 pounds) each when they were born on July 5.

Zoo visitors were able to watch through a window as the feisty felines were weighed one by one, showing their teeth and claws.

Zoo curator Konstantin Ruske says "we are very satisfied with the animals' development."