Day 12: Tapeworms Flashcards
What phylum are Tapreworms under
Plathelminthes
What are the sheep tapeworms called
Moniezia expansa
What are the cattle tapeworms called
Moniezia bendeni
What is the morphology of ruminant tapeworms
Very long
Wide, short proglottids with bilateral genitalia
Unarmed scolex with 4 large suckers for attachment
Square eggs with embryophore
What is the intermediate host in moniezia expanse
Oribatid mite
What are the clinical signs of moniezia expansa
Non-pathogenic when worm numbers are low
Diarrhea
Spontaneous cure in cattle ~3 weeks old
What is the pathology in moniezia expansa
Necrotic lesions only in heavy infections
What are the two horse tapeworm species
Anoplocephala perfoliata
Anoplocephala magna
What is the morphology of anoplocephala
Torpedo shaped tapeworms
Scolex is small with 4 suckers and 2 lappets
Triangular-shaped eggs with pyriform apparatus
What is the life cycle of anoplocephala
Main cestode of horses
Mite containing the larval stage is ingested by the horse
Where is anoplocephala perfoliata found in the horse
Ileocecal junction, cecum and colon (common)
Where is anoplocephala magna found in the horse
Small intestines (uncommon)
What is the intermediate host in horses
Oribatid mite
What are the clinical signs of Anoplocephala
Usually few clinical signs
inflammation at the ileocecal junction, colic, and intussusception
Low tolerance for tapeworm segments
What is the pathology of Anoplocephala
Heavy infections can cause hyperplasia of the ileum, intestinal erosions, perforations, and intussusception
What is the dog tapeworm called
Dipylidium caninum
What is the morphology of Dipylidium caninum
Scolex less than 0.5mm in diameter
Rostellum on the scolex can retract; it has small thorn-like hooks for attachment to gut
Proglottids are shaped like cucumber seeds and have bilateral genital pores
Proglottids have bilateral genitalia
What is the epidemiology of dipylidium caninum
Cyclophyllidean tapeworms which infect dogs and cats
Most common tapeworm of dogs, can occur in cats
What is the lifecycle of Diplylidium caninum
Intermediate stage is the cysticercoid that develops in fleas and biting lice
Dogs become infected by ingesting fleas or lice containing the cysticeroid
Adult tapeworms are in the small intestines
How long is the prepatent period for Diplylidium caninum
1 month
What is the diagnosis of diplylidium caninum
Recognized by egg capsules in a fecal flotation
Identify segments with particular morphology crawling on feces
What are the hosts for Taenia taeniaformis
Definitive host Cats and dogs
Intermediate hosts are rodents
What are the stages for Taenia taeniaformis
Intermediate stage is a cysticerus
Adult tapeworm lives in the small intestine
Proglottids or eggs are passed in the feces
Eggs are fully developed when passed in feces and are infective to the intermediate host
What are the clinical signs of taenia taeniaformis
Few to no clinical signs are seen in dogs and cats
What is the morphology of taenia saginata
Tapeworm is 5 meters long
Who are the hosts of Taeenia saginata
Definitive hosts is humans
Intermediate host is cattle
Intermediate stage is the cysticercus
What is the lifecycle of taenia saginata
In cattle the cysticerus encysts in muscle (heart and muscles of mastication)
Cattle become infected by contamination of pastures and feed by human feces
humans become infected by ingesting contaminated meat that is undercooked
What are the clinical signs in Taenia saginata
Few clinical signs in infected humans
Economic losses due to condemnation of carcasses
What is the diagnosis of Taenia saginata
Observation of cysticercus in meat at necropsy
How do you control Taenia saginata
Prevent contamination of human feces in cattle feed
Proper sewage management
Routine exam of feedlot workers
Good hygiene of feedlot workers
Who are the hosts for Taenia solium
Definitive host is humans only
Intermediate hosts include swine, camels, dogs, monkeys and humans
What is the lifecycle of Taenia solium
Humans can also be infected with cysticerus which can cause neurological disease
Humans can self infect leading to serious disease
What are the clinical signs of taenia solium
CNS signs in intermediate hosts
View measly meats as a delicacy
What is Echinococcus granulosus
Dog tapeworm
What is the morphology of echinococcus granulosus
Adult tapeworms that are very small
Adult tapeworms that have only 3 segments
What is the epidemiology of echinicoccus granulosus
Mainly in West and Northwest USA, Canada
What is the lifecycle of echinococcus granulosus
Intermediate stage is the hydatid which contains many daughter brood capsules
Tremendous reproductive potential afforded by the intermediate stage
Who are the hosts for echinococcus granulosus
Definitive host is the dog
Intermediate hosts are sheep
What is the zoonotic potential of echinococcus granulosus
Humans substitute for the intermediate host
Sheep and humans become infected by accidentally ingesting eggs from dog feces
How do you diagnose echinococcus granulosus
Fecal flotation
Other taenid tapeworm eggs cannot be distinguished from echinococcus eggs
What is the pathology in humans when infected with echinococcus granulosus
Mass on brain or liver
Immunological tests to detect cysticeri or hydatids
Surgical removal is necessary
What do Moniezia and anophlocephala eggs look like
Fecal float
Triangular or square with a hexacanth embryo in a pyriform apparatus
Rectangular proglottids are found in the feces
What do Taenid Tapeworm eggs look like
Spherical with thick wall with striations
Cannot be speciated by their ova so all have the same type of egg
Eggs fully infective to the intermediate host
What is the treatment of Cestode Infections
Praziquantel (Droncit)
Epsiprantel (Cestex)
