Lena Dunham's Dog Trainer Defends Her Decision to Re-home 'Really Aggressive' Lamby: 'She Was at Her Wit's End'

The Los Angeles dog trainer who spent a year working with Lena Dunham and her dog Lamby when his behavioral issues became too much for the actress to handle, tells PEOPLE that Dunham did everything possible before making the “very painful” decision to “re-home” her beloved pet.

Matt Beisner, who runs The Zen Dog, tells PEOPLE that some rescue animals are so traumatized that it sometimes takes months before they begin exhibiting behavioral problems.

Dunham, who adopted Lamby from the Brooklyn based no-kill shelter BARC, sparked a controversy in June via an Instagram post when she announced that she’d placed Lamby in a “professional facility” last winter after struggling with “four years of challenging behavior and aggression” that she was unable to treat with training or medication.

Her comments prompted BARC spokesman Robert Vazquez to tell Yahoo Celebrity on Thursday that he didn’t see any signs of aggression from Lamby when he was in the shelter.

“When she adopted the dog from us, it [the dog] wasn’t crazy,” Vazquez said. “I have pictures of the dog loving on Lena and her mom, which is weird if the dog was abused. It wouldn’t be cuddling with her or be in the bed with her ‘boyfriend’ in the pages of Vogue.”

But Beisner, who says he has “nothing but respect and admiration for those who work in the shelter world,” explains that Lamby’s change of temperament wasn’t that unusual.

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“The dog that we see in the shelter is often not that the dog that we see in the home,” he says. “And often the dog in the home on day one is different than the dog that we see at the six-month mark. It’s so predictable that I can almost put it on the calendar. When someone tells me they adopted a dog, I’m waiting for them to call.”

Lamby, he says, was already “really aggressive” when Dunham reached out to him for help last year after working with six other trainers. “She was at her wit’s end,” he says.

Beisner and his staff quickly learned why. “He didn’t want to be touched and he didn’t want to be handled,” he says. “When he came to us there were days where we had to carry his crate out to the yard and open it to let him come out because we couldn’t safely put our hands near him to get a leash on him to walk him.”

Besides biting, Lamby, who stayed at Beisner’s facility for extended periods of time, would drink his own urine. “That’s pretty typical for dogs that come from breeding houses or breeding farms where they live in crates that are just stacked on top of each other,” he says.

“He was really rattled, but he was also a great dog and if you set him up in a life that is tolerable, he’s actually a real joy and that’s what we were working towards.”

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Dunham, who Beisner describes as a “really proactive, diligent” pet owner, was initially unable to to consider finding another home for Lamby when her trainer first broached the subject.

But she eventually changed her mind and one of Beisner’s staff members, who’d fallen in love with the troubled dog, jumped at the chance to adopt him in March.

The adoption was handled quietly and received no publicity. Beisner had nearly forgotten about the incident until he received an email from Dunham on June 20, informing him that she was going to “break the silence” on Lamby.

The controversy which soon erupted, Beisner says, was ultimately a waste of time and energy — that could have been better used trying to find ways to help animals like Lamby.

“I think if we spent less time and energy attacking this individual owner — who I get it, is a lightning rod — and more energy talking about how we could help dogs,” he says, “we would have made a big difference in the past week.”