Veterinarians change white rhino's diet to promote fertility.

Veterinarians change rhino's diet to promote fertility. Researchers at the San Diego Zoo are using dietary changes to help endangered white rhinoceroses give birth in captivity. Scientists found that phytoestrogens in the rhinos' soy and alfalfa feed may have been interfering with fertility, so they removed the compounds from the animals' diets, and since 2014, three rhinos that previously could not successfully reproduce have done so. A rhino calf was born at the Safari Park on April 30 to a 16-year-old mother, Kiazi, whose age was well past the the average for first-time births. Christopher Tubbs, a senior scientist at the zoo’s Institute for Conservation Research, and his colleagues determined that compounds found in the soy and alfalfa pellets fed to rhinos were limiting their fertility. The researches said it is likely that a number of species living in zoo settings receive diets containing levels of phytoestrogens capable of affecting reproduction. source