DEAR DR. FOX: In September 2015, I wrote to you about the Facebook group "Does Bravecto Kill Dogs?" This group was formed to bring awareness to the side effects of the oral flea and tick medication Bravecto. Over 4,600 members have joined the group since our launch just five months ago, and we have a global reach. The number of reports on the group is now too high to count. However, a veterinarian in our group has received only two Food and Drug Administration (FDA) reports of adverse drug events (ADE) for Bravecto. Since Bravecto was approved in the United States in 2014, a total of 5,319 ADE reports have been filed with the FDA, including over 160 reported deaths. These numbers include only ADE reports filed in the U.S. We are aware of many additional reports of side effects and deaths in other countries.

The most common side effect continues to be vomiting and diarrhea, with blood in both, as well as seizures and skin irritation. Lethargy and failure to eat are also common symptoms. Additionally, there are an alarming number of reports of kidney and liver damage as well as reports of abnormal blood cell counts. The side effects are often not short-lived, and dog owners are incurring substantial costs for treatment.

We firmly believe the number of ADE reports is understated. Many owners don't know they can and should report side effects. Several members reported that their veterinarians stated that their dogs must have ingested poison. However, the members are confident the only new thing ingested was Bravecto. We encourage dog owners to come to the group for guidance on reporting side effects to Merck and the FDA, and for support as they manage symptoms.

I also want to note that a topical form of Bravecto was recently denied marketing authorization in Europe due to user safety concerns.

I have attached links to both the FDA adverse event reports and the Facebook group. Please encourage your readers to review this important information: yourpetsneedthis.com and facebook.com/groups/411371212394679/. -- S.W., Andover, Massachusetts

DEAR S.W.: Your efforts to collect documentation on this dubious pesticide is to be applauded, and I trust that readers will take note and also inform their veterinarians if this product is on sale at their clinics. It should be taken off the market, and safer alternatives and preventive measures adopted, as you can read on my website, DrFoxVet.net.

DR. FOX: Since about 2002, we have been rescuing cats and dogs. This started with my cat, Callie. She is over 15 years old, and she's gone from 6.2 pounds to 4.9 pounds in the past six months. She has been on Hill's Prescription y/d since she was diagnosed with thyroid issues a couple of years ago. The diet has kept the thyroid issue in check without meds.

Recently, her blood work came back as positive for kidney disease. She has been put on the k/d food. I feel helpless, as I understand that there is nothing I can do to help her. I have been feeding her small amounts of wet k/d with water added every two or three hours, and she does appear to be stronger.

Is there anything else I can do for her to make her more comfortable or to slow down the destruction of her kidneys? I do not know the signs that the situation is in its final stages. Can you help me understand this disease? -- T.J.W., Lanham, Maryland

High levels of iodine and fluoride in some cat foods and thyroid-harming environmental contaminants put cats at risk.

DEAR T.J.W.: I am sorry to hear about your cat's double-whammy -- chronic kidney disease preceded by hyperthyroidism, fortunately caught early enough for a special diet to help control.

Kidney issues can be associated with dental problems, so it is imperative that a thorough oral exam be given to all cats during their regular wellness examination.

For details about helping cats and dogs with chronic kidney failure, see " Care for Dogs and Cats With Renal Failure" on my website, DrFoxVet.net.

(Send all mail to animaldocfox@gmail.com or to Dr. Michael Fox in care of Universal Uclick, 1130 Walnut St., Kansas City, MO 64106. The volume of mail received prohibits personal replies, but questions and comments of general interest will be discussed in future columns.

Visit Dr. Fox's website at DrFoxVet.net.)

DEAR DR. FOX: I have a 3-year-old neutered male schnauzer mix who I adopted through a rescue a year and a half ago.

While he is very loving most of the time, he sometimes will lunge and snap at my husband when he nears the dog -- for no apparent reason. I must add that he is totally my dog and very possessive of me. I am the main caregiver, taking him for walks, etc.

He also gets upset when other people are around me, or even when my husband shows me affection. It is also sometimes difficult when we have guests as it takes some time for him to calm down. My husband and I are both retired and are home a good deal of the time. Our dog goes to doggie day care once a week, just so he can be with other dogs, and he seems to enjoy it.

I took him through obedience school and he did quite well. He is a very smart dog. I am just not sure how to correct him of this aggressive behavior. -- C.B., Arnold, Missouri

DEAR C.B.: You must consistently play the role of "alpha " with this dog, who thinks you are his mate and is clearly jealous of and threatened by your husband and others. I have had instances like yours where one spouse is actually jealous of the other's close bond with the dog, or else enjoys seeing the dog threaten and even bite the partner!

Certainly prior trauma (especially from a male human) may underlie this behavior, but in many instances the socialization process becomes narrowed to a single person; often, single-sex attachment with humans occurs, rather than blossoming into accepting all friendly people.

So you should have your husband be the one to walk the dog and give him food and treats for "sit" and "stay" obedience; he should also groom the dog. Any growling and threats toward your husband should be disciplined with a loud "no" and a time out.

Most dogs are bright enough to learn quickly that such unacceptable behavior leads to the worst punishment for a dog -- being shut out and all alone.

DEAR DR. FOX: You recently had a column that really spoke to me, about seniors wanting a pet but not being able to afford them. My husband and I can afford them, but we don't want the emotional heartache after our two dachshunds are gone. Both are 11 years old.

Wolfie has a large tumor in his jaw, and we don't want to risk having surgery, and Otto is doing reasonable well. As long as we smash Wolfie's food, everything is OK, but for how long?

You also wrote about Cecil the lion. I so agree with what you said about human activities and reproductive restraint. I have never heard or read anyone say this out loud. We continue to see commercials for starving children covered with flies and requests for money but never does anyone suggest they not have children if conditions are so poor. Why is this?

Also, I will never understand why anyone would want to hunt for sport. It's just barbaric to me and sickening. -- D.D., Arnold, Missouri

DEAR D.D.: Your dog with cancer of the jaw may benefit from a high-quality, high-protein diet with added super antioxidant fruits and vegetables and supplements. It can be difficult to assess animals' pain, but your veterinarian may want to prescribe a long-acting analgesic to help make your dear dog more comfortable.

I appreciate your response to my voicing concern about the lack of focus on human population control by so many philanthropic or conservation organizations. The right to breed is not some God-given right but an enormous responsibility, and as I stress in my book "Animals & Nature First," it is enlightened self-interest to embrace reproductive control by all good means. Otherwise wars, plagues and famine will continue and intensify -- nature's ways of regulating our numbers -- and the plight of animals wild and domesticated will be ever more desperate as we continue to put short-term human interests first.

Killing animals for sport is a perversion that is abhorrent to any humane sensibilities that we may have left as a "civilization."

(Send all mail to animaldocfox@gmail.com or to Dr. Michael Fox in care of Universal Uclick, 1130 Walnut St., Kansas City, MO 64106. The volume of mail received prohibits personal replies, but questions and comments of general interest will be discussed in future columns.

Visit Dr. Fox's website at DrFoxVet.net.)

DEAR DR. FOX: I was away working on our farm up north for several months; when I got back to Boca Raton, I found my wife had been feeding a stray cat. The cat had kittens, and the mother went off and left them with my wife. She was able to catch some of them and get them adopted, but others ran off. She thinks the mother may have another litter on the way.

What should we do? I told my wife not to feed stray cats, but she insists that what she is doing is right. -- S.A., Boca Raton, Florida

DEAR S.A.: Stray, lost, free-roaming and feral populations of domestic cats have become a plague in the United States. They are hunting from the North Woods of Minnesota to the swamps of Florida to the fragmented and fragile wilds of Hawaii. An internationally recognized ecologist told me recently, while attending a conference on biodiversity in Hawaii, that he witnessed a woman at the edge of a parking lot pulling out and scattering bags of cat food as she called into the surrounding scrub bush, out of which poured scores of cats.

Millions of well-intentioned people feed stray cats who come onto their property, sometimes adopting them. But they should do so only in collaboration with local Animal Control authorities. They should plan on getting the cat neutered, giving vaccinations and anti-parasite treatments and testing for feline immunodeficiency disease and leukemia virus infection. The goal is to break the reproductive cycle, responsible for the demise of songbirds and other indigenous animal species.

To simply feed hungry cats who come to your door is an irresponsible, selfish, feel-good activity that facilitates the continued survival and breeding of free-roaming cats, who are a threat to public health, and which also means great suffering for kittens. These young cats will either starve to death, die from overwhelming flea and worm infestations or from a virus or other infections that are a threat to endangered wild cat species such as the Minnesota lynx and the Florida panther.

DEAR DR. FOX: I adopted a 3-year-old female beagle from the county shelter and was told she came from a puppy mill. She has had pups in the past, but she's been spayed. She was scared of everything but that's gotten better, and now she is gentle, loving and quickly learned to handle stairs. She was house trained within three weeks. She follows me around the house all day. I named her Daisy. Problem is, she has separation anxiety. So when I leave, I have to get my daughter to come stay with her; even so, she cries and runs to the door while I am gone. The shelter vet said to give her Benadryl with diphenhydramine, but it hasn't helped at all. She doesn't like being in the car -- even sitting next to me with my hand on her -- and she works herself into such anxiety that she throws up. I tried a Rolaids once before going with her, and it did no good.

I tried leaving her in the house for five minutes, then 10, and it took awhile for her to calm down when I got back, but seemed OK. I then tried leaving for an hour on an errand. When I got back, she had chewed on the bottom of the door threshold seal, been up on the sofas and dining table and stool at the kitchen island. Since then, I've been for three hours for an appointment, and my daughter said she cried the whole time I was gone. What to do? -- K.G., Wentzville, Missouri

DEAR K.G.: You have put much love and patience into rehabilitating this traumatized commercial puppy mill breeding dog. These places should be closed down, but, as I document in my book "Inhumane Society: The American Way of Exploiting Animals," they are "inspected" and licensed by the government of a culture that puts money before compassion and respect for all life.

Your veterinarian should put your dog on a short course of Xanax or Valium, and you should try putting a few drops of lavender oil on a bandana around her neck. A small piece of fresh ginger (half of one teaspoon) in a ball of cream cheese helps stop motion sickness.

Keeping your dog in a crate for short periods of time when you are there and when you are briefly out of the house will protect the house; leave the door open when you're home, and you will eventually teach her that is her safe space.

(Send all mail to animaldocfox@gmail.com or to Dr. Michael Fox in care of Universal Uclick, 1130 Walnut St., Kansas City, MO 64106. The volume of mail received prohibits personal replies, but questions and comments of general interest will be discussed in future columns.

Visit Dr. Fox's website at DrFoxVet.net.)