It's not unusual for dogs - and sometimes cats - to go into a funk when the kids go back to school in the fall or off to college for the first time. They may even mope around when your work schedule changes.

"Part of that emotional attachment is a behavioral expectation that the two are going to do something predictable," says John C. Wright, an animal behaviorist and professor of psychology at Mercer University in Macon, Ga. "It's important to the cat on a daily basis. So you have a disruption in daily routine when someone leaves for school, a disruption in the emotional security the cat has, and that can result in both emotional and behavioral depression."

With emotional depression, the cat appears to be distraught and may vocalize more than usual, Wright says. Signs of behavioral depression range from lethargy - the cat tends to sleep longer, especially during those times when it's used to interacting with the person who's gone - to hyperactivity.

"For many people, when a kid goes off to college, the whole household is kind of depressed," Nitschke says. "It's a change in status in people's lives, and everybody reacts to that at some level."

Getting out and walking your lonesome dog is good therapy for both of you. If you face the prospect of a child going off to college or camp or basic training, start preparing your dog sooner rather than later, especially if your child and dog share a particularly close bond.

"If the kid going off to school was the major source of the dog's playtime, then when you take that out of the environment, there's going to be what seems like a deficit to the dog," Nitschke says. "I would increase the physically active interactions with the dog. It's not a bad idea to get the dog used to being walked or played with by other members of the household before the child goes off to college or back to school."

Animals and children are notoriously difficult to photograph, but the results are often worth the effort. This was certainly the case for the 2007 winners of the American Humane Association's annual Pets & Pals Photo Contest, who were announced today. Roberta Lites of Chandler, Ariz., and Oda Esterling of Norwalk, Conn., took top honors. Each will each receive $2,000 plus a non-cash prize from American Humane.

Lites' photo, "Alyana Kissing Snowbelle in The Sunflowers," captures a tender moment between a young girl and a golden retriever. American Humane's judges were also moved by Esterling's photo, "Lacey," which shows a kitten lounging comfortably on her caretaker's stomach.

American Humane received thousands of fantastic photos from photographers all over the nation. In addition to selecting grand prize recipients, the organization awarded winners in each of four categories: Shelter Life, Down on the Farm, Best Pals, and Families and Pets. Category winners will each receive $500 and a non-cash prize.

When the U.S. Food and Drug Administration approved implanting microchips in humans, the manufacturer said it would save lives, letting doctors scan the tiny transponders to access patients' medical records almost instantly. The FDA found "reasonable assurance" the device was safe, and a sub-agency even called it one of 2005's top "innovative technologies."

But neither the company nor the regulators publicly mentioned this: A series of veterinary and toxicology studies, dating to the mid-1990s, stated that chip implants had "induced" malignant tumors in some lab mice and rats.

"The transponders were the cause of the tumors," said Keith Johnson, a retired toxicologic pathologist, explaining in a phone interview the findings of a 1996 study he led at the Dow Chemical Co. in Midland, Mich.

Leading cancer specialists reviewed the research for The Associated Press and, while cautioning that animal test results do not necessarily apply to humans, said the findings troubled them. Some said they would not allow family members to receive implants, and all urged further research before the glass-encased transponders are widely implanted in people.