Videos of dogs chasing their tails may have people laughing on YouTube, but tail-chasing may be nothing to laugh at. Here’s what I told a reader.

Q: Why do dogs chase their tails?

A: A search on YouTube turns up thousands of videos of dogs chasing their tails. Usually we laugh when we see dogs performing this seemingly normal and entertaining behavior. But dogs don’t necessarily perceive their tails as furry prey or chase their tail just for fun.

In fact, science tells us that the behavior may be linked to an actual medical condition. A 2009 study published in the Journal of Small Animal Practice found that dogs who are tail chasers had significantly higher cholesterol levels than dogs who didn’t chase their tails.

Turkish researchers looked at 15 dogs with a tail-chasing habit, looking at their behavioral history, clinical signs, and results of lab work measuring total cholesterol, triglycerides, high-density lipoprotein (HDL, known as “good cholesterol” in humans) and low-density lipoprotein (“bad” cholesterol). None of the dogs had medical conditions that would account for the tail chasing. Fifteen control dogs had normal physical exam results and lab work. It may be that dogs chase their tails because the high cholesterol levels have blocked the flow of brain hormones controlling mood and behavior.

Other possible reasons include discomfort caused by dermatitis or anal sacculitis; welfare problems such as boredom, insufficient exercise or stress; or canine compulsive disorder, which may have a heritable component. Breeds prone to compulsive tail-chasing include bull terriers, German shepherds and Anatolian shepherds. If genetic factors are involved, it may be that the behavior was accidentally selected by way of being linked with a desirable trait.

Last but not least, some dogs simply enjoy chasing their tails, and there’s nothing at all wrong with them. But if you’re concerned about your dog’s tail-chasing — because it’s excessive or he’s injuring himself, for instance — talk to your veterinarian. There could be a fixable cause.

There’s more – including everything you need to know about veterinary specialists – in Pet Connection, the weekly nationally syndicated pet feature I co-write with Kim Campbell Thornton and my daughter, trainer Mikkel Becker.

Some dogs who won’t eat just need a little time to feel better, but there are many times when eating is essential to their health and recovery. Here are some tips to get them to chow down when they don’t want to.

Q: My dog is sick, and he has lost his appetite. Do you have any tips on how we can get him to start eating again?

A: It’s distressing when our pets are sick and don’t want to eat, especially since we can’t explain to them that eating is an important part of their return to health. Fortunately, there are a few tricks that can encourage your dog (or cat) to start eating again.

— Try baby food. Giving your pet the pureed meat in those tiny jars — on its own, or mixed with some rice or his regular food — may help to jump-start his appetite. It’s not a long-term solution, but rather a strategy for getting him to eat again until he’s starting to feel better. Then you can slowly transition him back to his regular diet. Before trying this, read the baby food’s label to make sure it doesn’t contain onion powder, which has health risks for dogs and cats.

— Warm the food. Heating your pet’s food on the stove, or briefly in the microwave, can increase its smell. If your dog can’t smell it, he won’t be inspired to eat it. Serve it just above human body temperature — about 99 degrees Fahrenheit — so that it’s warm, but not hot. Stir it first to eliminate any hot spots. It can also help to use a damp washcloth to gently wipe away any mucus accumulation from your dog’s nose so he can better smell what you’re offering.

— Offer small meals several times a day. Your dog might not feel like eating his normal amount of food all at once.

— Ask your veterinarian about medication that can help. If your dog has an upset stomach, your veterinarian can prescribe nausea-relief medication or an appetite stimulant.

There’s more – including fun gifts for pets and their people – in Pet Connection, the weekly nationally syndicated pet feature I co-write with Kim Campbell Thornton and my daughter, trainer Mikkel Becker.