Dangerous Food for Pets

dog
Photo by Dane County Humane Society

Dogs’ noses can get them into trouble. Whether sticking their cold nose into an unsuspecting area on your body or sniffing out a yummy scent on the counter, they often receive a scolding. I don’t have any deterrents for the cold nose, but keeping food items behind closed doors (or the dog behind a closed gate door) can keep your dog safe from harmful foods.

There are all manners of deliciousness that my collie, Scout, gets into. Scout particularly likes bread. Any bread will do, but fresh-baked bread is his favorite. Apart from my irritation at having to share with Scout when he steals a loaf off the counter, baked bread isn’t going to harm him much. But when I’m making homemade bread, I worry about him sniffing out the rising dough. Eating bread dough can be potentially life-threatening. A dog’s stomach is a perfect temperature for yeast to grow, making the dough expand. A large volume of dough can cause an obstruction in the dog’s esophagus and stomach, and the ethanol produced by the yeast can cause alcohol toxicity. Dogs that eat bread dough can have bloating, severe abdominal pain, retching or vomiting, and incoordination. They may need surgery to remove the dough.

The most common panicked phone call to the clinic is when a dog eats chocolate. Hershey’s kisses, brownies, and chocolate chip cookies seem to be commonly stolen treats. Why is chocolate such a concern? It’s due to the methylxanthines found in cocoa beans and cocoa butter. Theobromine and caffeine are methylxanthines; dogs are very sensitive to these chemicals, both of which cause hyperactivity, increased heart rate, tremors, vomiting, and diarrhea, with high doses causing lethargy and death. The closer chocolate is to the cocoa bean, the more methylxanthines are present.

Dry cocoa powder and unsweetened baking chocolate contain a lot of theobromine and caffeine. Landscapers often use cocoa bean mulch, which is very attractive to dogs and also contains high amounts of methylxanthines. Milk chocolate has low concentrations of methylxanthines, and white chocolate, since it doesn’t come from a cocoa bean, has virtually none. If your dog has eaten chocolate, call your veterinarian for advice. It’s important to know what kind of chocolate your dog ate, a ballpark idea of how much was consumed, and the weight of your dog. When Scout steals one of my brownies, it’s not a big deal since he’s a 70-pound dog. But if he ate one of my 80 percent dark chocolate bars, he would be in trouble.

Photograph provided by Dane County Humane Society

When I chop vegetables for dinner or snacking, Scout comes running. He knows he’ll get some bits of crunchy treats. Vegetables are just fine for dogs (and cats) to eat, with one big exception—those of the Allium family. This includes garlic, onions, leeks, shallots, and chives. There is a chemical in these vegetables—n-propyl disulfide—thought to damage red blood cells, causing them to lyse and break apart. Garlic and onions have the highest concentration of this chemical. Small pieces, dried flakes, powders, and even cooked onions and garlic can cause damage to the red blood cells, leading to anemia. Powders are more concentrated and smaller amounts can cause anemia. Even a small onion or garlic bulb can be enough to cause problems, so be careful when chopping these vegetables.

Some of you may have heard that avocados are toxic to dogs and cats. Apart from being a high-fat food which can cause pancreatitis, the flesh itself isn’t harmful. But the pit is a foreign-body hazard; eating it can cause an obstruction in the intestines. Avocados are toxic to birds, however. The toxic compound is persin, which is found in the leaves, fruit, bark, and seeds of the avocado. So while it’s fine to give a sliver of avocado to your dog, keep it away from your pet bird.

Fruit is more deliciousness for Scout. He sits by my side when I crunch into an apple because he knows he will get the core. While apple seeds do contain a cyanide compound released when the seeds are crushed, they need to be chewed up and not just swallowed whole. Even if crushed, there is not enough cyanide to cause any serious problems. But if I’m eating grapes and one falls on the ground, I am quick to pick it up, as grapes and raisins can be a problem in dogs. Toxicologists still don’t know why some dogs will develop acute kidney failure after eating grapes or raisins. They’ve ruled out fungal organisms, parasites, and heavy metals. Grapeseed extract appears to be safe, so the toxin isn’t in the seed.

Since it appears to be in the fruit or skin, avoiding grape juice is a good idea, too. The lowest recorded amount of grapes or raisins causing kidney failure comes out to be about three grapes or raisins per two pounds of body weight. So a 10-pound dog could probably eat 15 grapes or raisins without any problems. But a minibox of raisins contains 30, which will be eaten up pretty quickly by a dog. It’s best just to get into the habit of not sharing your grapes or raisins with your dog, but one dropping on the floor is not a big deal.

Photograph provided by Dane County Humane Society

What else does Scout like? Peanut butter! Apart from being high in calories that lead to weight gain, there is nothing wrong with giving your dog peanut butter. It’s great for hiding pills, and we use it in the clinic as a distraction while giving vaccines. Other nuts are generally okay, too, except for macadamia nuts. It isn’t known why, but eating them can cause weakness, depression, vomiting, ataxia (wobbliness or uncoordinated walking), and tremors. Unless you have a small dog, a few nuts aren’t a big concern, but problems can be seen if a dog eats more than one nut per two pounds body weight.

If you’re watching calories and eating sugar-free peanut butter, don’t give this to your dog. Many sugar-free foods, including chewing gum, protein powders, baked goods, chewable vitamins, and candy, may contain xylitol. Xylitol is a naturally occurring sugar with one-third the calories of refined white sugar. It’s often used in gums because it has been shown to decrease cavity formation. While it doesn’t harm us, it does stimulate insulin release in dogs, which causes the dog’s blood sugar to drop dangerously low (hypoglycemia), potentially causing liver failure and death. This hypoglycemia can occur up to three days after ingestion of the food. The toxic dose starts at 50 milligrams per pound body weight. A piece of gum can contain anywhere from 300 to 1,500 milligrams of xylitol. If your Labrador retriever gets into your purse and eats just three pieces of gum, that could be enough to cause severe problems. Definitely keep all your xylitol-containing products well out of your dog’s reach.

So while there are a lot of foods you can use as treats, it’s important to remember the ones to place out of reach of your pet. If you think your pet may have eaten something that could be toxic, please call your veterinarian or animal poison control for advice. You may find that the amount eaten won’t cause more than a little diarrhea, but if it turns out to be toxic, quick intervention could be key to saving a life.

Lori Scarlett, DVM, is the owner and veterinarian at Four Lakes Veterinary Clinic. For more information, visit fourlakesvet.com .