Cestodes

Diphyllobothriidean

Dipylidium caninum
Taenia crassiceps
Taenia hydatigena
Taenia multiceps
Taenia pisiformis
Taenia serialis
Echinococcus granulosus
Echinococcus multilocularis

Overview of Life Cycle

Two major groups of cestodes are parasites of dogs – the Cyclophyllidean or “true” tapeworms, and the Diphyllobothriidean (formerly Pseudophyllidean), which are sometimes referred to as “primitive” tapeworms.
Tapeworms of dogs have indirect life cycles that require specific intermediate hosts.
Cyclophyllidean cestodes usually have indirect life cycles requiring one intermediate host. Dogs infected with adult cyclophyllidean tapeworms shed egg-laden proglottids in their feces. When the eggs are consumed by the appropriate vertebrate or arthropod intermediate host, larval cysts develop. Dogs are infected when they ingest these larval cysts during grooming or predation.
Diphyllobothriidean cestodes have indirect life cycles that require two intermediate hosts. The adults in the small intestine discharge operculated eggs from a midventral genital pore; these eggs are then passed in the feces. When the egg contacts water, a ciliated embryo hatches and is ingested by the first intermediate host, a copepod, where the first larval stage (procercoid) develops in 2-3 weeks. When the copepod is consumed by a second intermediate host, the next larval form develops (plerocercoid also called sparganum). Transport (paratenic) hosts may also be important in the life cycle of Diphyllobothriidean tapeworms. Dogs are infected when they ingest plerocercoid larvae in intermediate or paratenic hosts during predation or scavenging.
For information on individual species of tapeworms please click on the above links.

Disease

Disease in dogs due to the presence of adult cyclophyllidean cestodes in the small intestine is considered uncommon, although passage of proglottids may be associated with perianal irritation.
Occasional cases of tapeworms leading to impactions that may present similar to linear foreign bodies have been reported.
Infection with diphyllobothriidean cestodes has been associated with gastrointestinal disease in dogs. Clinical signs reported include diarrhea, weight loss, and vomiting which usually resolve following appropriate anthelmintic therapy.

Prevalence

Prevalence data generated by fecal flotation alone almost certainly underestimate the frequency of infection with cyclophyllidean cestodes because proglottids (and thus eggs) are focally distributed in fecal material and because eggs are heavy and do not readily float; a given fecal sample is often negative for tapeworm proglottids or eggs, even in the presence of an infection.
In one study, fecal flotation failed to identify infection in the majority of dogs harboring adults of Taenia spp. or Dipylidium caninum.
Although they are seen in some areas of North American, in general, infection of dogs with diphyllobothriidean tapeworms is not as common as infection with cyclophyllidean cestodes. Fecal flotation is more likely to identify the eggs of Spirometra or Diphyllobothrium latum than cyclophyllidean cestode eggs.

Site of Infection and Pathogenesis

Adult tapeworms are found in the small intestine of dogs.
The common cyclophyllidean cestodes typically do not cause significant disease in dogs, but because they are aesthetically unpleasant and may pose a zoonotic health risk, treatment is warranted.
When dogs become intermediate hosts and develop metacestodes in the abdominal or thoracic cavity (see Mesocestoides, Echinococcus), severe disease and fatality may result.
Although not all infections with diphyllobothriidean cestodes result in overt clinical disease, vomiting, diarrhea, and weight loss that resolve following treatment have been reported.

Treatment

For treatment information, please see specific recommendations.
Treatment of tapeworms in dogs must be combined with appropriate management, such as flea control and prevention of ingestion of prey species; in the absence of these changes, re-infection is likely to occur.

Selected References

Conboy G. Cestodes of dogs and cats in North America. Vet Clin North Am Small Anim Pract 39:1075-1090, 2012.
Raether W, Hänel H. Epidemiology, clinical manifestations and diagnosis of zoonotic cestode infections: an update. Parasitol Res 91:412-438, 2003.

Synopsis

CAPC Recommends

Dogs should be treated for cestodes with a combination of effective anthelmintics and management changes to prevent re-infection (flea control, discourage predation or scavenging behavior)
Because fecal flotation is unlikely to identify cestode infections when they occur, routine treatment of dogs may be warranted
Controlling tapeworms in dogs addresses the aesthetic concerns associated with these parasites and limits the risk of zoonotic infection

Species

A number of different cestodes are reported from dogs. Those of greatest concern for dogs in North America include:

Cyclophyllidean

Diphyllobothriidean

Dipylidium caninum
Taenia taeniaeformis
Echinococcus multilocularis

Overview of Life Cycle

Two major groups of cestodes are parasites of dogs – the Cyclophyllidean or “true” tapeworms, and the Diphyllobothriidean (formerly Pseudophyllidean), which are sometimes referred to as “primitive” tapeworms.
Tapeworms of dogs have indirect life cycles that require specific intermediate hosts.
Cyclophyllidean cestodes usually have indirect life cycles requiring one intermediate host. Dogs infected with adult cyclophyllidean tapeworms shed egg-laden proglottids in their feces. When the eggs are consumed by the appropriate vertebrate or arthropod intermediate host, larval cysts develop. Dogs are infected when they ingest these larval cysts during grooming or predation.
Diphyllobothriidean cestodes have indirect life cycles that require two intermediate hosts. The adults in the small intestine discharge operculated eggs from a midventral genital pore; these eggs are then passed in the feces. When the egg contacts water, a ciliated embryo hatches and is ingested by the first intermediate host, a copepod, where the first larval stage (procercoid) develops in 2-3 weeks. When the copepod is consumed by a second intermediate host, the next larval form develops (plerocercoid also called sparganum). Transport (paratenic) hosts may also be important in the life cycle of Diphyllobothriidean tapeworms. Dogs are infected when they ingest plerocercoid larvae in intermediate or paratenic hosts during predation or scavenging.
For information on individual species of tapeworms please click on the above links.

Disease

Disease in dogs due to the presence of adult cyclophyllidean cestodes in the small intestine is considered uncommon, although passage of proglottids may be associated with perianal irritation.
Occasional cases of tapeworms leading to impactions that may present similar to linear foreign bodies have been reported.
Infection with diphyllobothriidean cestodes has been associated with gastrointestinal disease in dogs. Clinical signs reported include diarrhea, weight loss, and vomiting which usually resolve following appropriate anthelmintic therapy.

Prevalence

Prevalence data generated by fecal flotation alone almost certainly underestimate the frequency of infection with cyclophyllidean cestodes because proglottids (and thus eggs) are focally distributed in fecal material and because eggs are heavy and do not readily float; a given fecal sample is often negative for tapeworm proglottids or eggs, even in the presence of an infection.
In one study, fecal flotation failed to identify infection in the majority of dogs harboring adults of Taenia spp. or Dipylidium caninum.
Although they are seen in some areas of North American, in general, infection of dogs with diphyllobothriidean tapeworms is not as common as infection with cyclophyllidean cestodes. Fecal flotation is more likely to identify the eggs of Spirometra or Diphyllobothrium latum than cyclophyllidean cestode eggs.

Site of Infection and Pathogenesis

Adult tapeworms are found in the small intestine of dogs.
The common cyclophyllidean cestodes typically do not cause significant disease in dogs, but because they are aesthetically unpleasant and may pose a zoonotic health risk, treatment is warranted.
When dogs become intermediate hosts and develop metacestodes in the abdominal or thoracic cavity (see Mesocestoides, Echinococcus), severe disease and fatality may result.
Although not all infections with diphyllobothriidean cestodes result in overt clinical disease, vomiting, diarrhea, and weight loss that resolve following treatment have been reported.

Treatment

For treatment information, please see specific recommendations.
Treatment of tapeworms in dogs must be combined with appropriate management, such as flea control and prevention of ingestion of prey species; in the absence of these changes, re-infection is likely to occur.

Selected References

Conboy G. Cestodes of dogs and cats in North America. Vet Clin North Am Small Anim Pract 39:1075-1090, 2012.
Raether W, Hänel H. Epidemiology, clinical manifestations and diagnosis of zoonotic cestode infections: an update. Parasitol Res 91:412-438, 2003.

Cestodes for Cat Last updated: Nov 1, 2016

Synopsis

CAPC Recommends

Cats should be treated for cestodes with a combination of effective anthelmintics and management changes to prevent re-infection (flea control, discourage predation or scavenging behavior)
Because fecal flotation is unlikely to identify cestode infections when they occur, routine treatment of cats may be warranted
Controlling tapeworms in cats addresses the aesthetic concerns associated with these parasites and limits the risk of zoonotic infection

Species

A number of different cestodes are reported from cats. Those of greatest concern for cats in North America include:

Cyclophyllidean

Diphyllobothriidean

Dipylidium caninum
Taenia taeniaeformis
Echinococcus multilocularis

Overview of Life Cycle

Two major groups of cestodes are parasites of cats – the Cyclophyllidean or “true” tapeworms, and the Diphyllobothriidean (formerly Pseudophyllidean), which are sometimes referred to as “primitive” tapeworms.
Tapeworms of cats have indirect life cycles that require specific intermediate hosts.
Cyclophyllidean cestodes usually have indirect life cycles requiring one intermediate host. Cats infected with adult cyclophyllidean tapeworms shed egg-laden proglottids in their feces. When the eggs are consumed by the appropriate vertebrate or arthropod intermediate host, larval cysts develop. Cats are infected when they ingest these larval cysts during grooming or predation.
Diphyllobothriidean cestodes have indirect life cycles that require two intermediate hosts. The adults in the small intestine discharge operculated eggs from a midventral genital pore; these eggs are then passed in the feces. When the egg contacts water, a ciliated embryo hatches and is ingested by the first intermediate host, a copepod, where the first larval stage (procercoid) develops in 2-3 weeks. When the copepod is consumed by a second intermediate host, the next larval form develops (plerocercoid also called sparganum). Transport (paratenic) hosts may also be important in the life cycle of Diphyllobothriidean tapeworms. Cats are infected when they ingest plerocercoid larvae in intermediate or paratenic hosts during predation or scavenging.
For information on individual species of tapeworms please click on the above links.

Disease

Disease in cats due to the presence of adult cyclophyllidean cestodes in the small intestine is considered uncommon, although passage of proglottids may be associated with perianal irritation.
Occasional cases of tapeworms leading to impactions that may present similar to linear foreign bodies have been reported.
Infection with diphyllobothriidean cestodes has been associated with gastrointestinal disease in cats. Clinical signs reported include diarrhea, weight loss, and vomiting which usually resolve following appropriate anthelmintic therapy.

Prevalence

Prevalence data generated by fecal flotation alone almost certainly underestimate the frequency of infection with cyclophyllidean cestodes because proglottids (and thus eggs) are focally distributed in fecal material and because eggs are heavy and do not readily float; a given fecal sample is often negative for tapeworm proglottids or eggs, even in the presence of an infection.
In one study, fecal flotation failed to identify infection in the majority of cats harboring adults of either Taenia taeniaeformis or Dipylidium caninum.
Although they are frequently seen in some areas of North America, in general, infection of cats with diphyllobothriidean tapeworms is not as common as infection with cyclophyllidean cestodes. Fecal flotation is more likely to identify the eggs of Spirometra or Diphyllobothrium latum than cyclophyllidean cestode eggs.

Site of Infection and Pathogenesis

Adult tapeworms are found in the small intestine of cats.
The common cyclophyllidean cestodes typically do not cause significant disease in cats, but because they are aesthetically unpleasant and may pose a zoonotic health risk, treatment is warranted.
When cats become intermediate hosts and develop metacestodes in the abdominal or thoracic cavity (see Mesocestoides), severe disease and fatality may result.
Although not all infections with diphyllobothriidean cestodes result in overt clinical disease, vomiting, diarrhea, and weight loss that resolve following treatment have been reported.

Treatment

For treatment information, please see specific recommendations.
Treatment of tapeworms in cats must be combined with appropriate management, such as flea control and prevention of ingestion of prey species; in the absence of these changes, re-infection is likely to occur.

Selected References

Conboy G. Cestodes of dogs and cats in North America. Vet Clin North Am Small Anim Pract 39:1075-1090, 2012.
Raether W, Hänel H. Epidemiology, clinical manifestations and diagnosis of zoonotic cestode infections: an update. Parasitol Res 91:412-438, 2003.
Adolph C, Little S, Downie K, et al. High prevalence of covert infection with gastrointestinal helminths in cats. JAAHA 51:359-364, 2015.

Synopsis

CAPC Recommends

Cats should be treated for cestodes with a combination of effective anthelmintics and management changes to prevent re-infection (flea control, discourage predation or scavenging behavior)
Because fecal flotation is unlikely to identify cestode infections when they occur, routine treatment of cats may be warranted
Controlling tapeworms in cats addresses the aesthetic concerns associated with these parasites and limits the risk of zoonotic infection

Species

A number of different cestodes are reported from cats. Those of greatest concern for cats in North America include:

Cyclophyllidean

Diphyllobothriidean