Animals’ behavioral responses to diseases may help veterinarians better understand why animals act the way they do, according to a new study out of the University of California at Davis.

A new study by Benjamin Hart, DVM, Ph.D., explains that basic strategies for survival and reproduction can explain various animal behaviors.

Hart’s study, "Behavioral defenses in animals against pathogens and parasites: Parallels with the pillars of medicine in humans", takes an in-depth look at how animals behave in response to diseases. His study looks at various animal disease-control strategies including physical avoidance and removal of pathogens and parasites, animal-style herbal medicine to prevent or treat infections, and animal care of sick or injured group members, among other behavior strategies.

Hart’s research specializes in clinical animal behavior and the behavior of domestic animals. He has always been interested in animal behavior, he says.

"I came into veterinary medicine with a background in basic animal behavior – the behavior of animals in nature," Hart says. "I soon became interested in how animals survived, and even thrived, in nature with no medical services available – no vaccines, no modern medications, no nursing care."

Having a better understanding of animal behavior can help veterinarians better answer their clients’ questions about their pets’ behaviors, Hart says.

In his current study, Hart and his team of researchers set out to analyze disease-fighting behaviors in animals, seeking to find out why animals often behave the way they do. Hart dug deep what he calls "herbal medicine" in animals, referring to behaviors such as grass eating by dogs and cats.

"We explored the ‘medicine cabinet’ in the mouth for caring for wounds, cleaning up germ-ridden nipples, preventing genital diseases," Hart says. "We looked at herbal medicine, animal style. In a paper we argue that grass eating by dogs and cats is basically not because they feel ill but a self medication, which in nature, keeps intestinal parasites reduced."

Hart says that cat and dog behaviors have an innate behavioral foundation stemming from their wild ancestors. Studying behaviors such as the value of sickness behavior in combating acute infections and the role of den sanitation in house training can help veterinarians learn more about why animals behave the way they do.

Those behaviors can range from stool eating by dogs to grass eating by indoor cats.

"One of my latest ventures is considerable work in understanding stool eating by dogs, a disgusting problem that we now relate to canids in nature," Hart says. "For grass eating in indoor cats, understanding that it is an instinct should help us control their attraction to poisonous house plants and to give them a grass garden. Understanding the concept of sickness behavior helps us to facilitate this behavior to take advantage of the value in combating acute infections."

Hart says that veterinarians can offer better treatment of problem behaviors in dogs and cats by understanding why dogs and cats naturally act the way they do.

"This realm of behavior is important in understanding animals in nature and in dogs and cats," Hart says. "Sometimes the treatment of problem behaviors in dogs and cats can be improved by understanding the role of the behavior in nature."

While Hart’s research benefits veterinarians’ understanding of animal behaviors, it also has greater implications for human health as well. Understanding animal health and behavior can help doctors better understand human health and the idea of "one health", the concept that all living health is inter-related.

"One health has been with us since the evolution of ancient, hunter-gatherer people, along with animals that usually thrived in an environment teeming with pathogens and parasites," Hart says. "Understanding that much of behavior has an innate basis can help in preventing and resolving problem behaviors."