Dear Dr. Fox:

I have an odd question for you. While talking to my housemate, we got into the subject of schizophrenia and dementia. I wondered whether all mammals can have such problems. And what about reptiles and birds?

M.W.F., San Francisco

DF: Behavioral changes in animals caused by various factors can produce symptoms that resemble conditions seen in humans. In 1968, I brought together experts from around the world to contribute to the first textbook on the topic, titled “Abnormal Behavior in Animals.”

It served as a catalyst for more research and clinical studies of behavioral problems in animals captive and wild, including all avian and mammalian species. Reptiles and amphibians are more difficult to “read,’’ behaviorally.

In summary, many abnormal behaviors seen in humans are virtually identical to those seen in other animals, such as obsessive-compulsive disorders including self-mutilation and repetitive movements (such as crib-biting in horses), anxiety, post-traumatic stress disorder, depression, catatonia and seizures — even with hallucinations. The latter might be interpreted as a form of dementia triggered by some intense, often fear-evoking stimulus, especially when there is no escape.

Many dogs developed “air-snapping’’ behaviors after air raids in Britain during World War II, and dogs in Pavlov’s Leningrad laboratory, terror-stricken during a flood, remained traumatized long after. Such reactions can be interpreted as a form of dementia or OCD and are often triggered by fear and the inability to escape or hide.

Certainly, many captive species become demented as a consequence of extreme confinement, separation anxiety and boredom, a problem in dogs caged or crated all day in so many homes, as well as in sows on factory farms. Degenerative changes in the brain related to aging, and possibly genetics and nutritional deficiencies, can lead to dementia in humans and other animals. One form of dementia in cats shows virtually identical changes in the brain to those seen in Alzheimer’s disease in humans.

Changes in brain function and behavior in humans and other animals have an organic, rather than a psychological/emotional, origin. They can be attributed to various external environmental factors, such as endocrine-disrupting chemicals, viral and parasitic infections, adverse vaccine reactions, and poisoning from mercury and lead.

An organic, biochemical basis for abnormal behavior that may be interpreted as schizoid is seen in some dog breeds with sudden, unpredictable aggression, which might be improved by medications and nutraceuticals that increase serotonin levels in the brain.

Dear Dr. Fox:

Help! Our 20-month-old cockapoo has terrible separation anxiety.

We put her in her crate at night downstairs, but when she wakes up (sometimes as early as 3 a.m.), she barks continuously until we let her out. We’ve tried letting her “bark it out,’’ but that isn’t working. Perhaps we are too impatient.

Obviously, we’ve not taught her well. Any ideas on how to change this behavior?

J.H., Oak Hill, Va.

DF: The problem is not that you are being impatient or that you’ve failed to train her properly. The issue is that dogs are pack animals. This means that your dog needs to be with the family and not put into a crate for the night.

Proper crate-training is a gradual process of helping the pup adapt to being in a confined space for a short period, gradually increasing in duration. Treats and toys in the crate often help. The goal is to help the young animal feel that the crate is a rewarding place of security, her den, and not some kind of punishment and deprivation of being with the family.

Try moving the crate into your bedroom, making it like a cozy den, with the crate door open so she can enter and leave as she chooses. She might prefer to sleep on the bed with you, or on your floor in a soft dog bed, if not in the open crate. This is normal behavior for a pack animal. I hope these are feasible options for you and your family.

Dear Dr. Fox:

My letter concerns the euthanasia of pets. Our animal companions will suffer tremendous trauma simply because of their deep love for us.

During euthanasia, stay beside your pet and stroke them lovingly as they leave this world. Speak familiar words of love as the injections are being administered, and say your goodbye then.

I was blessed in having our well-trained, kind veterinarian make that suggestion and guide me through those difficult moments.

Make plans for taking care of your pet’s remains, too. In our case, the date was set, my husband dug the grave the night before, and I took care of the rest. It’s just something we must learn to deal with. There might be times when one must leave a deceased companion with the veterinarian, or times when the weather doesn’t permit digging, there’s no one to do it for us or our health problems prevent it.

I still cry from the loss of Tater, Cujo, Harley Ray, Sophie Jordanna, Tia Xena, Prancer, Sally Ann, Tommy Tom, Pookie Tootie and many more. Humans, be proud, and speak out for those dear and loved companions. Learn more from your veterinarians. Ask questions.

M.L., Humboldt, Tenn.

DF: Many readers of my column will appreciate your concern and encouragement to be with their animal companions at the time of euthanasia administration.

It can be emotionally challenging for some people to be with their animals at this time, but I agree that courage is called for to be with the animal — to hold and comfort them. Not all veterinarians will allow every client to be present, for a variety of reasons. Others offer in-home euthanasia and in-home hospice care — humane, compassionate services that I advocate for those who can afford them.

Taking the deceased animal home and allowing surviving animals to view the body might help with their grieving and sense of loss. Some animals might seem indifferent, just as with some people after the death of a family member. I wish that more people understood how deep the grieving experience can be, for both animals and humans, after losing a beloved animal companion.

Burial on one’s own property might be prohibited in some municipalities, so do your research. Cremation services and legal burial plots are available in most communities.

Dear Dr. Fox:

My husband and I are vegan. We feel bad having to feed our newly adopted cat, Timmy, meat and fish, but the vet says that is right. I have heard that there are special diets you can make or buy so that cats will be healthy on a vegan or vegetarian (eggs and dairy) diet. Can you send me more information?

Y.T., Arlington

DF: This question often comes up in my column, and I must reiterate that cats are obligate carnivores and that we should not impose our own values and dietary choices on them. They must have a daily intake of animal protein and fats, ideally from various organ parts and different animal species, preferably organically fed and humanely raised.

As for your own diets, I applaud your veganism. In today’s world, with over 7 billion people, vegetarianism is an ethical imperative. Vegetarianism and veganism occupy the higher moral ground over daily meat and fish consumption for people in most parts of the world, where there are nutritious alternatives that do not involve the slaughter of billions of animals.

There are sound, scientifically documented reasons for such enlightened dietary decisions, including humane concerns over animals’ suffering and the economic, ecological, environmental and public-health costs of a meat-based diet.

Michael W. Fox, author of a newsletter and books on animal care, welfare and rights, is a veterinarian with doctoral degrees in medicine and animal behavior. Send letters to animaldocfox@gmail.com or write to him at United Feature Syndicate, 1130 Walnut St., Kansas City, Mo. 64106.

2017 United Feature Syndicate