food with Mario batali. And more from our Lowe's oasis barbecue. Most of us with pets think we can explore the moods of our friends. They can get anxious just like us. Dan Harris has discovered we can... See More
food with Mario batali. And more from our Lowe's oasis barbecue. Most of us with pets think we can explore the moods of our friends. They can get anxious just like us. Dan Harris has discovered we can learn a lot from their experience. Reporter: This adorable little wisp of a dog named Frisbee is completely Normal, most of the time. But then, sometimes, seemingly out of the blue, he'll go on a fierce growling and tail-chasing joint. His owners brought him to the vet to treat his outbursts. A huge number of pets are on the drugs. Reporter: A fascinating and overlooked truth. Animals are capable of losing their minds in ways that are similar to the ways that human beings lose their minds. And we can also find them again, thankfully. Reporter: In a new book called "Animal madness," Dr. Braitman says E animals have OCD, anxiety and depression. Like this chimp, named bobby, traumatized by his years of a research subject, has made a huge turnaround, thanks in part to psychiatric drugs and treatment from human doctors. I knew he wanted help. You could see it in his eyes. Reporter: As with humans, a major factor in psychological recovery for animals, is love. Even if it's from a different species, entirely. Look at this goat, after being rescued from an animal order, where he lived squalor for a decade, the two animals were sent to separate shelters. Mr. G refused to eat or go outside for six days. But look what happens when jelly bean finally arrived. Mr. G perked up and ran outside. He gave jelly bean a kiss. And for the first time in days, he eats. One of the interesting things you point out is that animals can recover with love, even if it's the love of an entirely different species. Absolutely. Social animals tend to do better in the presence of other creatures who are emotionally healthy or who they know. Reporter: An interspecies love story that should give pause to anyone who doubts the emotional complexity of the animals we share with this world. Dan will have more about animal madness tonight on "Nightline." Now, a final check of the
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