The Cabinet secretary who rode a horse to work on his first day is letting his employees bring their dogs to the office.

Interior Secretary Ryan Zinke will announce in an email to employees Thursday morning the start of “Doggy Days at Interior,” a program that will launch with test runs at the agency’s Washington headquarters on two Fridays in May and September.

The new policy will make Interior the first federal agency to go dog-friendly — and cement Zinke’s status as the Trump administration’s most visible animal fan. Zinke earlier this month arrived at his new workplace astride Tonto, a bay roan gelding who belongs to the U.S. Park Police and resides in stables on the Mall.

President Trump, meanwhile, remains pet-less, a status that makes him the first U.S. leader in 150 years without a companion animal and leaves the White House without a first dog or cat. Vice President Pence and his family keep two cats and a rabbit at their Naval Observatory home, though those critters keep a relatively low profile.

Zinke, a fifth-generation Montanan, retired Navy SEAL and former congressman, said his dog policy’s primary goal is to boost morale at the far-flung Interior agency, which includes the National Park Service, the U.S. Fish and Wildlife Service, the Bureau of Land Management and six other departments. Interior ranked 11th in employee morale of the 18 largest federal agencies in last year’s Best Places to Work in the Federal Government survey, with just 61 percent of its 70,000 employees saying they’re happy in their jobs.

“I’m taking action to establish a pilot program for Doggy Days at Interior!” Zinke will say in his 9 a.m. missive to Washington-area employees, which shows two photographs of him with his wife, Lolita, and their 18-month-old black and white Havanese dog, Ragnar.

“Opening the door each evening and seeing him running at me is one of the highlights of my day,” Zinke’s email says. “I can’t even count how many miles I’ve driven across Montana with Ragnar riding shotgun, or how many hikes and river floats Lola and I went on with the little guy. But I can tell you it was always better to have him.”

The new policy, which has never been tried in the risk-averse federal government, puts the Trump administration in the vanguard of public institutions with dog-friendly policies. Members of Congress have been bringing their dogs to the U.S. Capitol since the 19th century, but few other taxpayer-funded workplaces have gone to the dogs.

Private companies, on the other hand, are increasingly touting their dog-friendliness as an employee perk. Among the most prominent are Kimpton hotels, the biotech firm Genentech and Google, which says in its code of conduct that “affection for our canine friends is an integral facet of our corporate culture.”

In a survey conducted last year by Banfield Pet Hospital, the nation’s largest chain of veterinary clinics the vast majority of U.S. employees and human resources managers at pet-friendly companies said the policies improved morale, lowered stress and decreased guilt about leaving pets at home.

Zinke, an avid hunter and fisherman, promised on his first day as secretary earlier this month to bring a dog-friendly office policy to Interior. The pledge, along with his promise to preserve public lands, drew loud applause as he addressed employees in the headquarters cafeteria.

“It’s a very exciting initiative that’s close to his heart,” said Heather Swift, a Zinke spokeswoman. “Every day he visits a different hallway in the building to introduce himself and somebody asks him when we’re going to have puppy days.”

But there are obvious concerns about having dogs at the office, which is why the policy is launching slowly as a pilot, officials said. Zinke’s staff has been consulting with agency attorneys in recent weeks to work out parameters for the dogs, including whether they’ll need to be leashed or be limited to a certain size. It’s likely they’ll be to be fully housebroken, vaccinated and have no history of aggression.

Other possible complications when Fido reports to Interior: Fleas, bites, people with allergies, and pets who may, in a new environment, relieve themselves indoors.

“I understand some of you may have concerns about this policy,” Zinke’s email says. Employees who “would rather not interact with dogs at the workplace” will be allowed to telework when dogs are around or have “other flexibilities.”

Ragnar was a frequent visitor to Zinke’s Capitol Hill office and rode on his campaign bus when Zinke was running for Congress. Ragnar is also the secretary’s fishing companion, though he does not join him on hunting trips.

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