A female Southern White Rhino calf was born on April 30 to first-time mother Kiazi and father Maoto in San Diego WAP (California, USA)!

Kiazi’s pregnancy was very exciting for researchers at the San Diego Zoo because she had never conceived before. At 16 years old, she is past the average age that most female Southern White Rhinos have their first calf.

Scientists at Research Institute of the zoo have been working for years to determine why southern white rhino females born in zoos tend not to bear offspring as often as their wild relatives. This problem is not found in other species of rhinos living in zoos. Through extensive research, it was discovered that the animals may be sensitive to compounds called phytoestrogens found in soy and alfalfa, which are a component of the animals’ diets in zoos. During their 16-month gestation, female calves could be exposed to the compounds through their mother’s diet, resulting in infertility issues later in their life.

Changing the mother diet seems to have brought results.

For more information you can read the full story here