Several dog owners tried to calm and hold down their pets, but the owners' cortisol levels did not rise. Dogs that lived in multi-dog households behaved similarly, but their cortisol levels remained more stable.

"We don't really know why the dogs in the multi-dog households showed this pattern," said Dreschel. "There may be some other influence of living with other dogs that mediates their stress response. In the wild, canines are pack animals, and it is likely that the survival advantages of pack living remain in our domestic canines."

She added, "An interesting side note is that in the multi-dog households, there was very little contact between the dogs during the storm. In fact, in many of the situations, the non-affected dog totally ignored both the affected dog and the recording. The affected dogs didn't 'seek out' the non-affected dog, either."

Dog trainer Sue Toldo, however, does think that owners can help their stressed-out dogs during storms.

She explained that dogs "read their owner's body language."

She also advises that it is best to train dogs when they are puppies by playing with them, distracting them from the sites and sounds of thunderstorms, and also by acting "like (the storm) doesn't bother you at all."

Toldo said she believed such conditioning can help dogs to ignore storms.

For canines that did not receive this puppy training, and for owners who cannot have more dogs, Dreschel offered this advice.

"I would recommend that owners of severely phobic dogs speak with their veterinarian or with a veterinary behaviorist about treatment possibilities for their dog," she said.

"There are a variety of treatment options available including desensitization, behavior modification, pheromone diffusers, and short and long-term anti-anxiety medications for severely affected dogs."

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