NewLec25-12-62บทนำทั่วไปของหนอนพยาธิตัวตืด

Order Cyclophyllidea 14 families of the order have been recognised 6 families found in domestic animals and man are important

Order Cyclophyllidea 1. Family Mesocestoididae 2. Family Anoplocephalidae 3. Family Davaineidae 4. Family Dipylididae 5. Family Hyminolepididae 6. Family Taeniidae

Family Mesocestoididae  The presence of four suckers  The absence of a rostellum and hooks  The median ventral position of genital pore and the presence of two vitelline glands  The eggs become enclosed in a thick-walled par-uterine organ



Family Mesocestoididae Mesocestoides lineatus, M. variabilis Occurs in the small intestine of the dog, cat, wild carnivores. Two intermediate hosts

Family Mesocestoididae 1st intermediate host= oribatid mites (cysticercoid is produced) 2nd intermediate host= dog, cat, birds, reptiles, amphibia (tetrathyridium is formed )

Family Mesocestoididae  The complete life cycle of Mesocestoides has yet to be worked out  The larval form infective for the definitive host is a third-stage larva called a tetrathyridium and is found in the peritoneal cavity of mammals and reptiles and in the lung of birds

Family Mesocestoididae  A cysticercoid larval stage is hypothesized to precede the tetrathyridium, possibly developing from the oncosphere in an insect, oribatid mites (Loos- Frank, 1991)

Family Anoplocephalidae  The presence of large suckers  The absence of a rostellum and hooks  The proglottids are usually wider than long and each has one or two sets of reproductive organs

Family Anoplocephalidae  The genital pores are marginal  The testes are usually numerous  The uterus may persist or be replaced by egg pouches, or the eggs may pass into one or more par-uterine organs

Family Anoplocephalidae  Each egg has three coverings  An outermost vitelline membrane  A middle albuminous coat  An innermost chitinous membrane

Family Anoplocephalidae  The egg has pear-shaped structure being called the “Pyriform apparatus”

Family Anoplocephalidae  The intermediate hosts are mites of the family oribatidae (cysticercoid is formed)  Anoplocephala magna, A. perfoliata Moniezia expansa, M. benedeni, Avitellina spp.



Anoplocephala perfoliata Small lappet behind each



Family Anoplocephalidae  Moniezia spp. have unarmed scolices with four large suckers and very wide segments with bilateral genitalia  They are found in the small intestine of cattle, sheep, and goats

Family Anoplocephalidae  Interproglottidial glands at the posterior margin of each segment extend the full width of M. expansa but occupy only the midzone of the M. benedeni segment

Family Anoplocephalidae  The square-shaped egg of Moniezia found in cattle feces is one of the few eggs that appears internally the pear-shaped (pyriform apparatus) characteristic of anoplocephalid eggs can be seen

Family Anoplocephalidae  Tapeworms of cattle, sheep, and goats all belong to the family Anoplocephalidae

Interproglottidian g Moniezia benedeni

Moniezia benedeni ; mature segme Testes







Family Davaineidae  The presence on the rostellum of numerus small, hammer-shaped hooks  The suckers are usually also provided with hooks  Genital organs usually single

Family Davaineidae  The eggs may pass into egg- capsule (Raillietina spp.) formed by the uterus or into a par-uterine organ formed by denser parenchyma near the uterus  Parasites of birds chiefly

Family Davaineidae  Larval stage found in intermediate host (slug, ant, fly)  Davainea proglottina, Raillietina tetragona, R. echinobothrida, Cotugnia digonopora



Numerous testes Cirrus Vagina Ovary Vitellaria Davainea -Large cirrus and antero-lateral position of genital





Raillietina echinobothrida; mature segmen

Family Dipylididae  The rostellum is usually provided with hooks  The suckers may or may not be unarmed  Genital organs single or double  The testes are numerous

Family Dipylididae  The uterus may be sac-like or branched and persist or the eggs pass into parenchymatous capsules or par-uterine organs  Dipylidium caninum

Family Dipylididae  In Dipylidium caninum, the scolex has four suckers and a retractable rostellum armed with several circles of thornlike hooks

Family Dipylididae  Segments are shaped like cucumber seeds and have bilateral genital pores

Family Dipylididae  The genital apertures of Dipylidium caninum lie slightly behind the middle of the segment  Each egg capsule may contain from 5 to 20 eggs

Family Dipylididae

Family Dipylididae Cysticercoids of D. caninum develop in fleas (Ctenocephalides spp.) and biting lice (Trichodectes canis)





Scolex Neck Strobila Gravid segment Mature segments Immature segments





Dipylidium caninum Lateral excretory Testis (double genitalia) Vas deferens Cirrus Cirrus sac Vagina Ovary Vitelline glan



Family Hymenolepididae  The rostellum has a single row of hooks (H. nana) or absence (H. diminuta)  The suckers are usually unarmed  The genital pores are unilateral, rarely double

Family Hymenolepididae The genital organs are as a rule single and the testes are few in number, mostly three per segment

Family Hymenolepididae The uterus is generally persistent and sac-like The eggs are enclosed in three envelopes