Probably the most common parasite seen. For most animals fleas are a nuisance causing itching and discomfort. However, some animals have a severe allergic reaction to fleas, resulting in hair loss,irritated skin and secondary infections. Heavy flea infestation in very young or very old animals can cause anemia and iron deficiency, fleas can also transmit tapeworms to your pet. Flea allergy dermatitis, also known as FAD, is caused by hypersensitivity to antigenic material from the salivary glands of fleas (flea saliva). Flea saliva contains many antigens which some dogs and cats are very susceptible to. Flea allergy dermatitis is the most common allergy in dogs and is a very itchy and painful condition. Your dog may not have a flea infestation, but it only takes one bite from one flea to trigger the allergic reaction. Since fleas spend part of their life cycle in the environment, they can be difficult to eliminate. Often it is necessary to treat both the animal and the environment to get rid of the fleas.
Flea eggs are white in color and oval shaped with round ends. they are deposited on the host and readily fall into the environment with in a few hours. After hatching, the maggot-like larvae begin to feed on blood in adult flea feces, organic debris, flea eggshells, and other flea larvae. The flea larvae will not develop outdoors in areas that are exposed to sunlight. Common outdoor sites are shady areas where pets tend to rest. Common indoor sites are undisturbed, protected places such as carpets, under furniture and along baseboards. The time in which these larvae develop depends on temperature and humidity. When ready the larvae will spin a cocoon, these cocoon can be found in soil, on vegetation, in carpets, under furniture, and on animal bedding. The Adult flea can begin to emerge about 8 days after initiation of pupal development; with all fleas emerging by day 13 and 78% relative humidity. Though adult fleas may remain dormant in the cocoon for up to 30 weeks at 75% relative humidity. Staying dormant will occur longer when there is no appropriate environmental stimuli. The adult flea can now emerge in as little as 13 days or as long as 50 weeks depending on temperature and other stimuli.. The adult flea will begin to feed immediately when on a host. The blood excreted by the adult flea dries into reddish-black pellets deposited in the pets coat, which is referred to as “flea dirt”. When using a flea comb on your pet you can usually pick up this flea dirt, which is an indication your pet has fleas even if no adults are seen at the time. Egg production begins with in 20 to 24 hours of the females taking their first blood meal. The female flea can produce 40 to 50 eggs per day, which can cause a quick infestation if not taken care of promptly.