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Allamanda Chihuahua Kennels

The Flea

Probably the most common cause of itching we see in dogs and cats is from infestation by fleas. In fact, flea related itching accounts for 50% of the itchy dogs compared with around one percent which turn out to be allergic to food. The classic case of the dog chewing or rubbing at the base of it's tail due to a flea allergy results in hair loss and, if the rubbing goes on, thickened and darkened skin. Flea allergy can also present as food chewing, face rubbing, rubbing of the belly along the ground etc .

It may be complicated by infection by bacteria and yeast which make the itching more severe and control more difficult. The classic tail baldness, however, may also be seen in conditions that have nothing to do with fleas.

Have you heard any of the following, statements about fleas?

* The flea jumps off a dog to lay its eggs and then jumps back on as the dog passes by.

* Fleas jump easily from one animal to another.

* Fleas can survive the winter by jumping off a dog and going into hibernation until spring.

* Once the flea is in its cocoon it is protected and no spray can kill it.

* The flea spends 95% of its time off a dog and only jumps back on to feed.

* Flea breeding can take place anywhere a dog walks.

EVERY ONE OF THESE STATEMENTS IS WRONG!

So how is it that much of what is said about fleas is so wrong? Mostly because a lot of what is assumed about the dog flea has been extrapolated from other flea species (which are able to do all of the above). To know what's right we need to take a look at the life-cycle of the dog and cat flea.

LIFE CYCLE

1. Adult Flea

Once the female jumps onto a dog it immediately begins to suck blood. 0nce the flea has fed, it's gut lining changes so that it needs to continually feed on blood or it will start to digest it's own intestinal tract. It is virtually suicide for the flea to jump off a dog once it has hopped on, it does not generally do so. After feeding for two to three days, the female flea begins to lay eggs in the dog's coat.

2. Eggs

Flea eggs are very small, about the size of a grain of sand. If you look closely, it is possible to see them. They are very smooth and easily roll off your dog into the environment where they hatch as larvae within one to ten days.

3. Larvae

The flea larvae are about two millimetres long. The larvae feed on organic matter and dried flea faeces that fall from the dog's coat. They are quite active and move into areas that are dark and have high humidity. Inside the home this means deep inside the carpet pile or a dog's bedding. Outside the home they move under leaves, grass, soil etc to get to places that are moist. The larvae are VERY sensitive to drying out and so they mostly survive only in spots outside that are, quite cool. That is, all spots that a dog likes to lie to keep cool during the heat of summer. Rarely are the larvae able to survive in areas of full sun, so that even if a dog has the full run of a yard, the flea development doesn't take place over the entire yard, but rather just in the areas where a dog likes to sleep and rest.

4. Pupae

The flea larvae spin a loose cocoon from a silk - like secretion, where it develops to an adult flea. The silk is sticky and small grains of sand etc stick to it which helps camouflage it. These cocoons can be found deep in the carpet pile, on the dog's bedding, in the soil and under organic matter where a dog likes to sleep. Contrary to popular opinion the cocoon doesn't actually offer much protection from changes in the environment or insecticides.The protection comes from the fact that the cocoons are most conunonly buried, where pesticides don't reach acid the iiiierociiiiiate doesn't change. The pupal stage normally lasts eight to nine days but can last up to six months, which is how many of the fleas survive the winter.

5. Adult Fleas

The fully developed flea waits in it's cocoon until it senses a dog walking nearby. Then it hatches and begins to jump towards the object that it sensed. The hatching is very fast, in fact a flea is able to emerge from it's cocoon deep in the carpet pile and jump in less than one second! Often people see these newly emerged fleasjumping when they return home after a holiday. The newly emerged flea is hungry and begins to feed on a dog straight away. After two to three days the female flea starts to lay eggs and the whole cycle begins again.

When conditions are ideal for flea breeding, this cycle can take place in 10 days. In winter, when humidity is low and stages of development are slowed, the cycle may take up to seven months to complete. It is the lower humidity in winter rather than the temperature drop that slows the life cycle down and means we see fewer fleas. All stages of the life cycle are extremely sensitive to changes in humidity, much more so than to changes in temperature.

HOW TO EFFECTIVELY TREAT FLEAS

The best way is to start early in spring when the numbers of fleas are low. All animals in the household should be given an oral insect growth regulator (only available from a vet). This will prevent the fleas from breeding so the numbers of fleas will never build up. If you see any fleas later in the season, all you need do is treat with something that will kill the adult fleas.

If you do not want to use an insect growth regulator or have started later in the season when there is already a large number of fleas on your dogs, you will have to follow the step by step program below.

1. Treat the environment

The aim of treating the environment is to kill newly emerged fleas, prevent the completion of the life cycle and continue to kill new adults as they emerge from their cocoons.

Unless you are prepared to effectively treat the environment you will NEVER obtain good control of the fleas on your dog.

HOW TO TREAT THE ENVIRONMENT

1. Inside

a) Vacuum the carpet and dispose of contents.

b) Treat the carpet with a product containing insecticide and an insect growth regulator.

Several of the insecticidal foggers have this combination. The areas where your dog rest need to be carefully treated, also under furniture, because the flea larvae crawl from the major traffic areas in a room.

The major spray will kill any fleas that have emerged, but generally the treatment doesn't get the pupae which are at the base of the carpet. So commonly we see a sudden increase in flea numbers 2 - 3 weeks after treatment. Retreating at this time will kill these new fleas.

2. Outside

General effort should he concentrated in these areas where flea breeding is most likely ie, your dog's favourite resting spots, around and under bushes and moist shady areas. Spray with a yard and kennel insecticide registered for this use.

The oral insect growth regulators will ensure that the developmental stages of the flea's life cycle are stopped without actually having to spray the environment. These products do not kill any of the fleas already in the environment prior to starting medications. If you are seeing large numbers of adult fleas on your dog, it may still be necessary to follow the steps listed above to get the situation tinder control.

3. Treat Your Pet

Rules to follow

a)Treatment of your dog with a product that kills fleas must take place simultaneously with environmental treatment.

b) All animals in the household must be treated at the same time (including cats).

c) Follow the label directions exactly, make sure the label says the product is OK for both dogs and cats.

By following these steps you will have the best chance at beating the flea. One last tip, start treatment EARLY. Don't wait until there are large numbers of fleas crawling all over your dog and you before attacking the problem. (An ounce of prevention is still worth a pound of cure.)

By Michael Shipstone BVSC

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