DEAR DR. FOX: I am writing concerning my dog’s flea/tick/heartworm medicine.

My dog is 11 years old and he has been on Revolution ever since I’ve had him. But now, my vet will not give me Revolution unless I have him tested for heartworm. Why would this test be necessary if he has used the medicine for 11 years? -- N.R., Boynton Beach, Florida

DEAR N.R.: Your veterinarian does not want to run the risk of killing your dog.

That could happen when anti-heartworm medication is given to a dog who already has heartworms. The medication will kill the worms, which then break up into small pieces that can block major blood vessels and cause a stroke. This is why a blood test is done before starting medication. For those dogs who are on such preventive medication year-round, I would still run the test because of possible drug resistance, which internal parasites have been known to eventually develop.

People living in regions that have winter, and that lack the mosquitoes that transmit heartworms and other diseases, can safely take their dogs and indoor-outdoor cats off the preventive medication for a few months. But they still must always have their animals’ blood tested for any sign of infestation before resuming medication.

It is totally irresponsible for people with dogs on such oral medications not to pick up and safely dispose of their poop (by burying it, composting it or securing it in the garbage) because traces of the drug will be in the stools, and may kill beneficial coprophagic insects that play an important environmental function in recycling animal waste. This is a huge problem on conventional livestock farms, where cattle and sheep are treated with antiparasitic drugs.

DEAR DR. FOX: I am a journalism student at Northwestern, writing a piece on the animal shelter system.

I was hoping to hear what you think the biggest challenges facing this system are currently. I know overpopulation is a big part of the problem, but I’m curious if you think something has changed in this country that has led to the current numbers we are seeing today (per animals in shelters) or if you think this has been a continuous problem. -- M.Y., Chicago

DEAR M.Y.: Here are some of my concerns as many animal shelters continue to fill up:

1. Society as a whole still has a throwaway attitude toward animals.

2. Many people are uninformed, or at least ill-informed, about cat and dog behavioral needs. This could be rectified by animal shelters partnering with local veterinarians, vet technicians and certified animal behaviorists. For example: Shelters could providing “puppy classes” -- not just play groups, but educational sessions for owners/caregivers on training, handling, socialization and basic care.

3. Cats are stressed in shelters and should be in separate, sound-proof quarters, away from dogs.

4. Behavioral assessments for adoptability of both cats and dogs is often inadequate, leading to unwarranted euthanasia -- especially with breed prejudice (pit bulls and dogs who look like them) -- and release (of cats who are afraid and hiss).

5. So-called “no-kill” shelters often dump cats deemed unadoptable in communities under the banner of “community cats” or TNR (trap, neuter, release), which is inhumane and puts wildlife at risk.

6. Animals in separate cages in shelters often become cage-bound, fearful and defensive, and suffer lives of deprivation in no-kill shelters when not soon adopted. Group-housing of compatible, quarantined dogs and cats in enriched habitat enclosures, ideally with safe outdoor access, prevents such problems and helps make animals more adoptable.

7. Staff and volunteers must be dedicated to animal socialization. Human interaction (grooming, petting and play) with incarcerated animals is an essential aspect of optimal shelter care and post-capture or surrender rehabilitation. Dogs need to be regularly walked by responsible and experienced handlers, in both harness and collar with a double leash, to prevent escape and to facilitate leash-training and trust.

8. Noise can be a big problem, especially with caged, barking dogs. Things that can help include soft music, recordings of dogs’ happy sounds, and having a resident gentle dog to calm and play with puppies and shy dogs and kittens. In group-housed cats, having a resident “ambassador cat” who shows affection toward caretakers -- which shy cats will witness, thus beginning to trust people -- can make a big difference in recovery and adoptability.

9. Inhumane methods of euthanasia (gas and decompression chambers, electrocution) are becoming something of the past, thanks in part to the Association of Shelter Veterinarians. Shelter staff need emotional support in dealing with cruelty and neglect cases and animal hoarders, as well as having to euthanize animals that are incurably suffering or cannot be rehabilitated for adoption for various legitimate reasons.

10. Greater community support and municipal funding of animal shelters and local humane societies is needed in many communities, as is outreach to schools and student visits to the shelters.

11. I support legislative initiatives banning the sale of cats, dogs, puppies and kittens in pet stores in order to encourage adoptions from local shelters and discourage online purchases, many of which are scams. See below for more on one such initiative.

MAINE BILL WOULD RESTRICT PET SHOP SALES OF DOGS AND CATS

Lawmakers in Maine are considering a proposal to restrict the sale of dogs and cats at pet stores in an effort to boost shelter adoptions. The bill, introduced by state Sen. Ben Chipman, would allow violators to be punished with a $500 fine per violation, as well as suspension or revocation of their license. (The Associated Press, April 25)

(Send all mail to animaldocfox@gmail.com or to Dr. Michael Fox in care of Andrews McMeel Syndication, 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 DrFoxOneHealth.com.)

DEAR DR. FOX: There is an out-of-control puppy scam on the internet. Scammers take someone else’s dog picture off their website and post it on their own. They collect and post beautiful pictures of puppies, plus wonderful, endearing videos of them, then “sell” the dogs which aren’t actually theirs.

Many popular smaller dog breeds sell for $2,000 to $5,000 from reputable breeders. These scammers sell theirs for a bargain at $500 to $700. The seller writes a whole page about what a wonderful family the dog will come from, not a puppy mill. One scammer I talked to said he was a consultant in California selling a dog from Virginia.

They only want cash or Western Union money. They won’t take a credit card. They told me they were willing to send a puppy with a “pet nanny” on a plane in -50 windchill weather to Minnesota from Virginia. They wanted me to be at the Minneapolis airport waiting for them. I knew the dog would never arrive, but another victim would have been standing there feeling totally stupid, out of money, heartbroken, with no dog!

The scammers I talked to all spoke with thick accents, and were a little hard to understand. They would never give me their complete address. I came within two minutes of losing $700 to one, before I was able to cancel my Western Union transaction.

There is a website listing the names of current dog scams: ipata.org/pet-scams. Look at that before you buy one. I don’t know how people can be so mean and greedy to do this to others. Shameful!

By contrast, a rescue dog is one you can see, play with, and learn if it is trained and fixed. So if that works for you, give one a loving home. -- J.T., Alexandria, Minnesota

DEAR J.T.: I hope many readers of this column will take note of your experience and pass it along to their friends and relatives who may be contemplating getting a dog or puppy.

I have raised this issue in earlier columns, and appreciate you sharing your story and concerns. In addition, I implore people not to purchase delicate, small breeds, and those like pugs and French bulldogs with pushed-in faces, since they are likely to face many health issues in their often-short lives. Adopt a dog or pup from your local shelter instead!

DEAR DR. FOX: My 8-year-old standard poodle dropped in his tracks after doing a short romp around our yard, an exercise he does regularly.

Just as he fell to the ground, he made a short, shrill sound and then did not move. I ran to his side and tried to resuscitate him with chest compressions and breathing hard into his nose. I believe he died instantly. This dog was in perfect health with no known heart ailments. He had been fine all day with absolutely no signs of illness or distress.

Necropsy of his heart, lungs and gastrointestinal system revealed nothing out of the ordinary, and the vet said there was no reason to send off any tissue samples for analysis. He presumed it could have either been an aneurysm or undiagnosed genetic heart defect.

I have never felt such anguish in my life.

Your thoughts? We want to get another poodle. -- C.W. Root, Naples, Florida

DEAR C.W.: This must have been a terrible shock for you.

At least your dog’s suffering, if any, was short before loss of consciousness. Most likely, there was a brain aneurysm that ruptured. Any vascular weakness can lead to a stroke when there is high blood pressure associated with kidney disease in older dogs and humans. And around where you live, dog owners should look out for toxic toads that can kill dogs from what seems like a heart attack, but usually with other signs including seizures and drooling.

TOAD WARING: FLORIDA DOG DIES AFTER PICKING UP BUFO TOAD

A dog in Tampa, Florida experienced seizures and died within minutes of picking up a Bufo toad in his mouth, according to his owner. Bufo, or cane, toads are reddish- to grayish-brown with a light yellow belly, and they secrete a toxin that is lethal to dogs and cats. (WFTS-TV, Tampa, Florida, April 3)

(Send all mail to animaldocfox@gmail.com or to Dr. Michael Fox in care of Andrews McMeel Syndication, 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 DrFoxOneHealth.com.)

DEAR DR. FOX: I have been reading about feeding dogs vegan diets, or vegetarian ones (including no meat, but still eggs and dairy). What is your opinion on this?

I am concerned about the environment and animal welfare, so I am a vegan, and I must say I feel better since I changed my diet. I know vegan diets are wrong for cats, but what about my dogs? -- R.F., Washington, D.C.

DEAR R.F.: Many dogs, especially German shepherds, get pancreatic insufficiency (run out of starch-digesting enzymes) when on a high-grain/starch diet. Some other breeds develop irritable and inflammatory bowel diseases and colitis, along with associated allergies from the secondary leaky gut syndrome.

Dysbiosis -- an unhealthy population of gut bacteria associated with biologically inappropriate diets -- can lead to other health problems that can be rectified by dietary corrections and supplements. Corn and wheat can cause seizures in dogs, and soy causes bloating and indigestion, indicative of food intolerance. A high-fiber diet can lead to constant hunger and malnutrition, while a high-carbohydrate diet can lead to obesity, diabetes, arthritis and other health problems.

Alternative dietary inclusions such as potato, pea flour and lentils (pulses) have been recently linked with dilated cardiomyopathy in dogs. High levels of lectins in these ingredients may interfere with uptake of taurine, which is an added supplement in most manufactured dog and cat foods. Deficiencies in omega-3, DHA and EPA fatty acids, and high levels of omega-6 from corn in vegan and vegetarian diets (for both dogs and people), are also a major concern. These fatty acids are essential for the neurological and visual development of puppies (so pregnant dogs, especially, should not be given vegetarian diets), and may also slow down cognitive decline in aging animals and help sustain cardiac health. Deficiencies can underlie serious skin disorders and inflammatory conditions.

Dogs and cats are often allergic to eggs and dairy products, or have varying degrees of dietary intolerance to them. Adding synthetic supplements to vegan and vegetarian diets in order to correct deficiencies can be problematic, as per recent recalls of dog foods containing excessive, toxic levels of vitamin D. (One recent example: truthaboutpetfood.com/seven-class-action-lawsuits-against-hills-pet-nutrition/)

My ultimate concern is that dogs (and cats) on biologically inappropriate diets may present clinical problems that some veterinarians will address primarily, and possibly exclusively, believing that the animals are being fed an adequate diet. Treating the symptoms and consequences of improper nutrition, rather than addressing the root cause, has happened in many instances -- especially with dogs and cats being fed manufactured pet foods sold by the veterinarians, along with profitable prescription diets.

These concerns and others about many conventional manufactured pet foods with “junk” and hazardous plant and animal ingredients condemned for human consumption are documented in the book that I co-authored with two other veterinarians, “Not Fit for a Dog: The Truth About Manufactured Cat and Dog Foods.” For more details and home-prepared recipes for dogs and cats, visit drfoxonehealth.com.

DEAR DR. FOX: I was reading this 2014 column of yours, about behavioral changes associated with flea and tick treatments, with great interest: is.gd/YdQhv3.

I have an 18-month-old Lab/golden mix who has shown aggressive behavior after receiving flea and tick medicine. Last year, we used a topical treatment and it totally changed her behavior. I called the vet and asked about this, and they said to wash it off of her and not to use it again. This year, we decided to use an oral medication (Bravecto) from the vet. Now, I read this article and realize that we have really harmed her for three months. She just got her first dose two weeks ago, and the behavior has restarted.

She is such a sweet girl, but right now I fear when other dogs come towards her, as she gets protective and aggressive. She usually loves everyone and everything.

My question: Is there any way to detox her body? -- M.G., West Palm Beach, Florida

DEAR M.G.: Your letter is important, and I am impressed that you found the reference to my earlier article on this issue.

I would like to hear from other readers whose dogs (and cats) have shown behavioral changes after application or oral treatment with insecticides to kill ticks and fleas. I am opposed to the routine preventive use of these drugs for animal health and environmental reasons, as documented on my website (drfoxonehealth.com). I also provide an integrative and safer approach to help prevent these and other external insects from infesting companion animals. It is only a matter of time before they evolve drug resistance.

Your dog will naturally detoxify and rid her body of these chemicals, a process you may facilitate by encouraging plenty of water intake with chicken- or beef-bouillon flavored water and a daily (human) dose of vitamin E, vitamin B complex, and milk thistle for seven days. These will support liver function, the main detoxifying organ of the body.

(Send all mail to animaldocfox@gmail.com or to Dr. Michael Fox in care of Andrews McMeel Syndication, 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 DrFoxOneHealth.com.)