|The study of parasites is called parasitology. It is an important discipline because internal parasites cause death and disease worth billions of dollars in animals each year. These parasites have highly evolved life cycles that make their elimination impossible. In addition, many internal parasites affect people with the potential for serious consequences.|
Dogs and cats (especially puppies and kittens) are routinely infected with internal parasites, sometimes without apparent evidence of the infestation until it is too late. This means that a pet can have internal parasites even though the fecal sample is negative. Fortunately, we have effective medications to treat most parasites.
Many of the medications we use to treat internal parasites, called anthelmintics, treat more than one parasite. The advent of these broad spectrum anthelminitcs makes treatment much more effective. We recommend all dogs and cats get a treatment for internal parasites every 6 months.
This section will discuss internal parasites that are commonly found in dogs and cats in our area. These internal parasites differ from external parasites, which usually affect the skin and ears of dogs and cats. Click here to learn more about external parasites.
Symptoms manifested by pets that are infected with internal parasites can vary, and depend on a pet’s age, nutritional status, parasite load, duration of infestation, etc. One of the most common symptoms of internal parasitism is diarrhea. Other symptoms include poor appetite, lethargy, coughing, and abdominal distention.
Some pets don’t show any symptoms while others can die from their infestation. Internal parasites tend to infest older and younger animals most commonly. Internal parasites can also make a pet more susceptible to other diseases. It is not uncommon for a puppy with Parvo virus to have internal parasites simultaneously.
Due to the prevalence of internal parasites in dogs and cats, their lack of symptoms in some cases, and the potential for humans to become infested also, your pets feces should be checked for internal parasites twice a year. Dogs and cats that are outside and exposed to other animals should have their feces checked more often.Routine worming should be performed on all dogs and cats every 6 months, even if the stool check for parasites is negative.
The majority of internal parasites are diagnosed by microscopic examination of the feces for eggs that are released by the adult female in your pet’s intestine. The number of eggs released in a given fecal sample can be variable, sometimes there aren’t any even though your pet has an adult female parasite in its intestines.
This means that a negative fecal report does not guarantee that your pet is free from internal parasites. In many cases we need to run numerous samples to feel comfortable that your pet is free of internal parasites. In some cases our doctor’s will treat for a specific parasite, even on a negative fecal sample, when they feel there is a likelihood of infestation, because some internal parasites eggs are notoriously hard to detect.
In some parasites a diagnosis is made by observation of the mature parasite in your pet’s feces or during an autopsy in your pet’s intestines. This is especially true for Tapeworms. Tapeworm eggs are difficult to detect during microscopic fecal analysis, so observation of the actual worm is how they are routinely diagnosed.
The two primary methods of fecal analysis are direct observation and fecal flotation. In direct observation a smear is made of some fecal material on a microscope slide and the slide is analyzed by one of our nurses for parasite eggs. It is used to detect eggs that don’t show up well during the fecal flotation.
Fecal flotation is the most accurate way to detect most internal parasites. A sample of fresh feces is put into a special solution that causes any eggs that might be present to float to the top and adhere to a cover slip. The cover slip is put on a microscope slide for analysis. This concentration of eggs substantially increases the chance of finding any eggs that might be present. Some eggs, notably Tapeworm eggs, dissolve during this process and might be undetected. This is the reason you can see Tapeworms in your pets stool yet the fecal analysis came back negative.
We have sanitary containers for you to use to obtain a fecal sample from your pet. Once the sample is obtained it should be kept cool until we analyze it. Analysis should be within 12 hours to increase accuracy.
The flotation solution has been added to the fecal container and a cover slip has been placed on the top to collect any eggs that float to the surface after a 5 minute wait.
The cover slip is put on a microscope slide and carefully scanned for the eggs of any parasite.
Internal parasites have very sophisticated life cycles that can make treatment difficult. Some of these life cycles involve mandatory maturation processes in other animals, including insects. Specific treatment modalities are set up to address these life cycles and will be discussed for each individual parasite in the following sections. It is important to follow these treatment regimens precisely.
Some parasites can only be controlled, not eliminated. In these cases it is important to check your pet’s feces routinely and to use medication on a long term basis.
There are new treatments for internal parasites that are very broad spectrum. They kill a wide variety of parasites, and are the medications we use as a routine wormer.