• Management Practices
• Anthelmintic Control

Control of endoparasites in cats is accomplished with chemicals. However, control of some parasites, particularly Toxocara and Taenia, may be aided by preventing cats from eating rodents and the viscera of domestic animals. However, drugs remain the mainstay of internal parasite control in cats.

Management Practices

The most important management practice for the control of feline endoparasites is effective sanitation. Faeces should be removed from catteries frequently. Exercise areas should possess hard, easy to clean surfaces. The use of disinfectants in cleaning is desirable. However, many parasite eggs are very resistant, and can be killed only by prolonged steam or flame thrower treatment.

Parasites usually develop best in warmth and moisture, so infection can be minimised by ensuring that all outside areas in catteries are constructed with good drainage, adequate ventilation, and, if possible, exposure to sunlight.

It is good management practice to have cats examined periodically for parasite infections and treated with the appropriate anthelmintics.

Anthelmintic Control

Drugs used to control nematodes and cestodes are termed anthelmintics. Chemicals may eliminate parasites in a variety of ways, such as paralysing them and allowing the host to expel them, by halting their ability to metabolise nutrients, thus killing them, any by limiting their ability to reproduce. Different chemicals may act on one or more of these ways. Anthelmintics should have the following characteristics:

• Be effective when used under a variety of conditions. Parasites vary greatly in their susceptibility to different drugs.
• Have a wide therapeutic index or margin of safety. That is, the dose of the drug used should be toxic to the parasite without causing any damage to the host.
• Be easy to administer

Since the beginning of this century, many chemicals have been used to eliminate parasites from their hosts. The earliest compounds were relatively ineffective, but much progress has been made in recent decades. The discovery of phenothiazine in the late 1930's was the first major breakthrough in the development of anthelmintics. This drug has a wide margin of safety and, when introduced, provided limited control of several important livestock parasites. Piperazine was first employed as an anthelmintic in the 1950's. It is still widely used because it has a high therapeutic index and is effective against Toxacara and Toxascaris.

A revolutionary advance in the control of internal parasites came with the introduction of thiabendzole, the first of the benzimidazole class of compounds in the early 1960's. This product has been extremely successful in the control of a wide range of nematodes. It is effective against the adults and also kills eggs and larvae. It is an effective treatment for Strongyloides infections.

The tetrahydropyrimidines, which include the products morantel and pyrantel, were also introduced in the late 1960's. They have a wide range of spectrum of activity, killing Toxascaris, Toxacara, Ancylostoma and Uncinaria adults.

The organophosphorous compounds, such as dichlorvos, are widely effective against nematodes in the gastrointestinal tract. These compounds are cholinesterase inhibitors, and therefore are toxic to the parasites and may be toxic to the host. When used at the correct dose, these drugs will kill the parasites without damage to the host. However, if other organophosphorus compounds are being used to treat external parasites, the two used at the same time may be sufficient to harm cats.

More recently developed drugs include oxantel and febantel.

Drugs used in the treatment of cestode infections include bunamidine, dithhiazanine iodide, diethylcarbamazine, and praziquantel.

Existing anthelmintics have a number of deficiencies which are:

• Some anthelmintics cause undue stress and can be toxic
• Many anthelmintics have limited spectra of effectiveness so several different treatment regimens have to be given if catss are infected by many parasites
• Few compounds, if any, are effective against larval forms migrating or dormant in body tissues

Damage to Host

Diagnosis