Pet Tip of the Month
May 2012: Pest Population Control
By Krystle Wright

Have you ever wondered why certain anti-parasite products are labeled for use on dogs only? What about why a dragonfly is like a bat? (And no, it’s not because they both fly.)

Last month we reviewed some of the dangers pests and parasites pose to your pets. Fleas, ticks and heartworms cause a range of problems when they infect an animal, with symptoms as mild as skin irritation or as severe as breathing problems, Lyme disease and death. Let’s talk a little about ways to control the pest and parasite population and protect your pet.

Biological methods of pest control are usually handled by local governments, but the subject is worth discussing when talking about pest population control. Think of biological parasite control as similar to a scenario in which you have mice in your attic, so you introduce a cat into the environment to cut down the population. Some biological means of pest control involve introducing new predators into the environment or increasing the amount of natural predators by importing them from other areas. Certain bats, for example, eat mosquitos, the culprit responsible for spreading heartworms.

Dragonflies are also predators of mosquitos, and are one case in which biological population control is superior to chemical control only. In nature, dragonflies eat mosquitos at almost all stages of the life cycle, but chemicals that are sprayed over a large environment to kill mosquitos have the unfortunate effect of killing dragonflies, too. The mosquitos that survive the chemical treatment no longer have natural predators to prevent them from infecting your pets.

Other methods of biological population control may affect parasites at different stages of their life cycles. For example, a strain of bacteria called Bt israelensis has been shown to kill mosquito larva when added to the water supply, without harming humans or other animals.

Here’s another interesting one: how do you keep mosquito larvae out of an outdoor water supply, like a decorative pond or the kind of tanks used for livestock? Add minnows. The same fish that fisherman use as bait also eat the mosquito larvae. It’s an easy way you can put biological pest control methods to practical use.

The bad news is that when a pet is infected with parasites, so is its environment – and that means your home can become contaminated. The good news is that there are things you can do to help. Mechanical methods of pest population control include basic cleaning strategies, like vacuuming, washing your pet’s bedding with hot water and steam cleaning where appropriate to get rid of parasites in your home. Make sure you clean especially well in areas where parasites can hide, like cracks and spaces between carpeting and woodwork. Bad outbreaks of parasites, especially fleas, may call for assistance from professional pest control companies to treat your house and outside property.

Chemical means of preventing and treating parasites are usually products or treatments you can apply directly to your pet. You can buy over-the-counter products in pet stores that are intended for this purpose, like flea collars and pest-fighting powders, sprays, shampoos and dips. The active ingredient in many of these products intended for dogs is a chemical called permethrin, a synthetic chemical that has proven to be only moderately effective, and the effects of these treatments are often so temporary that they fail to rid your pet of parasites completely for even a short period of time.

Permethrin has an added danger: it can be toxic to cats. Housecats have actually died from the use of permethrin-containing anti-parasite products intended for dogs. In rare cases, cats can even die from exposure to dogs that have recently been treated with permethrin products.

Prescription-strength products are usually more effective at preventing and treating parasites on your pet. Different medications attack parasites at different stages of their life cycle. Some, called adulticides, are intended to kill mature fleas, while others, like insect growth regulators (IGRs), stop flea larva and eggs from reaching maturity. Medications also vary in terms of application. Some are topical substances that come in a tube, and which you apply to a specific spot on the skin, usually between your pet’s shoulders. Other medications are taken orally, injected, or used in sprays or collars. Some medications are aimed more toward preventing fleas or ticks, while others target heartworms and intestinal parasites more.

Your veterinarian will be able to help you choose the best medication, or combination of medications, to prevent and control parasites on your pet. He or she can also make sure you have the correct dosage and the correct product for the animal type and size. If you have concerns (for example, if your pet is an outside-only dog or an indoor-outdoor cat that is at a higher risk for parasite exposure), ask your vet for a recommendation. A veterinarian can also advise you of what other methods of pest population control you can use to protect your pet, so don’t be afraid to ask, “What can I do?” next time you take Fido or Fluffy in for a checkup.

This article would not be possible without the help and guidance of Dr. William McAlonan, DVM, Wilwynn Animal Hospital,  496 Greenwich Road, Bridgeton, NJ.  (856) 451-0789