Using dogs bred to herd cattle to control elephants hasn't worked out so well at the Pittsburgh Zoo & PPG Aquarium, according to federal authorities. The Department of Agriculture has ordered the zoo to stop using cattle dogs in ways that cause "behavioral stress" to its African elephants, the Guardian reports.

Federal inspectors at the zoo last month found that the dogs had bitten elephants in the course of their shepherding work and displayed other aggressive behavior that disturbed the elephants.

Their report says they verified a news clip that "showed the elephants exhibiting signs of distress when charged by one of the dogs, including ear flapping, trumpeting, and turning and running away." The zoo was told to immediately cease using the dogs in ways that upset the elephants, although its CEO said their use was important for protecting human handlers, reports the AP.

"The dogs read the behavior of the animals and alert the keepers to any disruption in the herd, preventing potential safety concerns for the staff and elephants," she said in a statement.

PETA, which complained about the practice last year, hailed the USDA's decision. "When elephants, dogs, and human handlers freely mix, everyone is in danger," a lawyer for the group says, calling for the zoo to switch to a "safe and modern elephant-management method—or, better yet, to retire the elephants to an accredited sanctuary where they'll be free from harassment for the rest of their lives." (Click for a happier story about a baby elephant.)

This article originally appeared on Newser: Feds to Zoo: Stop Using Cattle Dogs on Elephants

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