Points on Pets: Fleas commonly become attached to pets
Apr 20,2007 00:00 by R.G._Elmor_DVM

Q: We are constantly trying to treat or prevent flea infestations on our three dogs. Although our neighbors say we should not have a flea problem next spring and summer due to severe winters, these nasty little varmints return as soon as temperatures become warm.

Fleas seem to be indestructible. What is the life cycle of the flea? How do they continue to propagate themselves in spite of all the new products designed to destroy them? Will fleas ever be eradicated?

A: It often seems like fleas are indestructible. No matter what is developed to prevent fleas, they always seem to be a problem that we cannot ignore.

Fleas are small, brown, wingless insects with laterally flattened bodies that can jump amazing distances. This allows them to attach themselves to any animals, including people, within their environments. Fleas cause minor irritation by crawling on the skin surface and by piercing the skin while feeding on their host's blood. Many animals experience allergic-type reactions when bitten by fleas.

After attaching themselves to their hosts, fleas feed voraciously; however, they digest only a small portion of the blood they actually ingest. The undigested blood becomes small pieces of fecal material called flea dirt. Finding flea dirt on a dog or cat is often the first sign that a flea problem exists.

Following feeding the female flea releases eggs. The average female flea puts down about three to 18 eggs at one time. During the lifetime of a flea, which is anywhere from 6 months to a year, a female flea can have several hundred eggs. However, an adult flea can live for only a couple of months when separated from their host animals.

Following an incubation of 2 to 12 days, flea eggs hatch into larvae. These are active, white-bristled worms with chewing mouth parts. Flea larvae grow and molt twice during a period from 9 to 200 days. The third molt produces an opaque white larvae that becomes quiescent. It spins a loose whitish to gray cocoon inside of which it develops from 7 days to 1 year. The adult flea then breaks out of the cocoon and looks for a host upon which to feed.

The life cycle of the flea can be as short as a few weeks and as long as a year. Although treating and preventing fleas on pets is important, a major effort for flea control should be directed at the premises where the eggs, larvae, pupae and adults can live for long periods of time. Treating animals for fleas without treating the environment is usually ineffective. Your veterinarian can give you the best advice regarding treatment of animals for fleas and preventing this annoying problem. It is unlikely that we will ever eradicate fleas from our world.

Q: We are wondering if throwing up hairballs is normal behavior for our cat. She usually does this after a period of agonizing retching. Since we are first-time cat owners, we are not prepared for this.

A: Although throwing up hairballs is common and considered normal behavior in cats, many owners find this distasteful. Surveys indicate that 50 percent to 80 percent of all cats throw up hairballs as often as once per month. Because cats spend a lot of time licking and grooming themselves, this is not surprising.

There are many remedies available to reduce the occurrence of hairballs in cats. These include medications, dietary supplements and scientifically formulated diets. Your veterinarian can give you advice about how to reduce the occurrence of hairballs in your cat.

Send e-mail to copleysd@copleynews.com or write to Pets, Copley News Service, P.O. Box 120190, San Diego, CA 92112-0190. Only questions of general interest will be answered in this column.