The Animal Doctor

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.


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 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.

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