While the estimates vary, approximately three to four million dogs and cats are euthanized (“put to sleep”) each year in the United States because too few people spay or neuter the pets they have, too few adopt their new pets, and too many give up their pets. Because space at shelters is limited, staff members must make the difficult decision to euthanize healthy animals that aren’t adopted within a certain amount of time.

Some animals may have several of these clinical signs, whereas others may have only one—perhaps an ear infection.

Toxicosis is disease due to poisoning. Chocolate contains two ingredients that can be toxic to pets—caffeine, and a chemical called theobromine. While dogs and cats are both very sensitive to the effects of caffeine and theobromine, cats are usually not attracted to chocolate, so chocolate toxicosis tends to be less common in cats.

Kidney disease is a very general term used to describe several conditions that can affect the kidneys or damage kidney cells. If kidney disease progresses, it can eventually lead to kidney failure and death.

Bad breath in pets may be a sign of periodontal disease that could lead to other health problems. Periodontal disease starts when plaque (a bacterial film) coats the tooth. Plaque hardens (calcifies) into tartar, a thick yellow or brown layer on the teeth. Tartar can irritate the gums, creating an environment where bacteria thrive. As the disease progresses, the gums become tender, red, and swollen and the bacteria continue to multiply. Eventually, the inflamed gums pull away from the teeth, creating pockets that trap more bacteria and food particles. The gums bleed, the roots of the teeth may become exposed, teeth may become loose, and your pet may feel pain when eating. If the bacteria enter the bloodstream, they can create problems for organs such as the heart, lungs, liver, and kidneys.

Diabetes mellitus is an illness caused by the body’s inability to either make or use insulin, which is a hormone produced and released by specialized cells in the pancreas. Insulin permits the body’s cells to take sugar (glucose) from the blood and use it for their metabolism and other functions. Diabetes mellitus develops when the pancreas doesn’t make enough insulin or when the body’s cells are unable to use available insulin to take glucose from the blood.

Obesity (the storage of excess fat) is usually caused by excessive food intake and insufficient exercise. One of the biggest problems in cats is overfeeding, which can lead to serious problems, including obesity, heart disease, and arthritis, resulting in a shortened life span. Your veterinarian can recommend a proper type and amount of food to maintain your cat’s ideal weight.

Dealing with an injured pet can be scary and frustrating. In many cases, you don’t know how bad the injury is, and your pet may not be acting normally. If your pet is injured, the first thing you need to do is try to remain calm. If possible, try to determine how severe the injury is, but remember that caution is extremely important when approaching an injured animal. Any pet, no matter how calm or friendly he or she may usually be, can bite or scratch when in pain.

Cats are known for grooming themselves, but a little help is never wasted. Regular brushing can help keep your cat’s skin and haircoat healthy and can be another way to strengthen the relationship between you and your pet.

Medicines in pill or capsule form are prescribed to treat a variety of conditions, but many cats dislike taking pills. Some medicines that are usually prescribed as pills or capsules can be changed (compounded) to a liquid or a powder for easier administration. If you have trouble giving your cat pills, ask your veterinarian if compounding is possible for specific medicines.

Inflammatory bowel disease (IBD) is a general term for conditions that cause the lining of the intestines to become thickened and inflamed. When this occurs, the digestive tract can’t absorb nutrients and move food substances properly. Certain portions of the digestive tract may be affected, or the entire length of the intestines may be involved.

Kidney disease is a very general term used to describe any one of several conditions that can affect the kidneys or damage kidney cells. If kidney disease progresses, it can eventually lead to kidney failure and death.

Cats are usually easy to litterbox train because they are naturally clean and prefer to bury their waste. First, make sure that your cat knows where the litterbox is. Confine your cat to a small area or room with clean water, fresh food, and a clean litterbox until he or she is successfully using the litterbox and seems comfortable. Do not use a covered litterbox during the training period because it might complicate the process. If your cat urinates or defecates outside the litterbox, place the waste in the litterbox; the smell should help your cat find and use the litterbox in the future. If your cat isn’t using the litterbox after a day or two, do the following: After your cat eats, place him or her in the litterbox, and briefly scratch the litter with your finger. However, don’t force your cat to stay in the litterbox; you don’t want your cat to have a negative experience in the litterbox.

Your veterinarian can see signs of gingivitis and tartar buildup by examining your dog’s mouth. However, since most periodontal disease occurs beneath the gum line, the only way to truly assess your dog’s mouth is to perform an examination while your pet is under anesthesia. Your veterinarian can use a dental probe to measure any loss of attachment around each tooth and take dental radiographs (x-rays) to assess for bone loss, abscesses, and other problems.

Rabies is a deadly disease caused by a virus that attacks the central nervous system. All warm-blooded animals, including wild animals, dogs, cats, and humans, are susceptible to it. Once clinical signs appear, rabies is generally fatal. However, the disease is also generally preventable through vaccination.

A wide variety of skin and coat conditions can cause your pet to itch and scratch, but pinpointing the problem can sometimes be difficult because many skin disorders have similar outward signs. Below are four major categories of skin conditions seen in cats and dogs.