African elephants in captivity are getting fat, and it’s a situation with potentially serious consequences for the species, say scientists.

Daniella Chusyd, M.A., is a doctoral student in the University of Alabama at Birmingham Department of Nutrition Sciences. She said:

Obesity affects about 40 percent of African elephants in captivity. Much as we see in humans, excess fat in elephants contributes to the development of heart disease, arthritis, a shorter lifespan and infertility.

Infertility is the aspect that may be most troubling. Nearly half of zoo African female elephants exhibit abnormal ovarian cycles, which, said Chusyd, is strongly correlated with a high body mass index. According to a 2011 report by scientists at the Lincoln Park Zoo in Chicago, zoos in the United States need to average about six births each year to maintain a stable elephant population. But the current average is only around three births a year.

Tim Nagy, Ph.D. is a professor in the UAB Department of Nutrition Sciences. He said:

Low birth rate is connected to abnormal ovarian cycles in elephants and virtually all large mammals, including humans. At the current birth rate, the findings of the Lincoln Park Zoo report suggest that the African elephant could be gone from U.S. zoos within 50 years.

With elephants in the wild continually threatened by diminished habitat, ivory hunting, war and political instability, zoos may provide the last bastion for preserving the species, said Chusyd. To better understand the link between obesity and infertility in zoo elephants, she has launched a study looking at body composition and inflammation in these animals.

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