penetration of schistosome cercariae through the skin 6 Schistosomal Hatching Test If feces containing viable schistosome eggs are diluted with approximately volumes of water, the eggs hatch within a few hours, releasing miracidia The miracidia are advantage of this characteris A stool specimen is homogenized by shaking in normal saline and then strained through two layers of gauze 2). The material is allowed to sediment, the supernatant is decanted and the sediment resuspended in saline. This process is repeated least twice 3). The saline is decanted and replaced with distilled water, and is suspension is placed in a flask. The flask is covered to i cm below the level of fluid in the neck of the flask Additional water is added if necessary. 4 )The flask is allowed to stand at room temper ature for several hours in ubdued light 5)detect the presence of free-swimming miracidia. The ty pical miracidium is a tiny, ciliated organism. It is long round form Miracidium swims ceaselessly during its short life. Free-swimming miracidia are very active, al though the miracidia do not have eyespots, they apparently have photoreceptors, and they are positively phototrophic
15 penetration of schistosome cercariae through the skin. 6 Schistosomal Hatching Test If feces containing viable schistosome eggs are diluted with approximately volumes of water, the eggs hatch within a few hours, releasing miracidia. The miracidia are positively phototrophic. The following procedure takes advantage of this characteristic. 1). A stool specimen is homogenized by shaking in normal saline and then strained through two layers of gauze. 2). The material is allowed to sediment, the supernatant is decanted and the sediment resuspended in saline. This process is repeated least twice. I 3). The saline is decanted and replaced with distilled water, and is suspension is placed in a flask. The flask is covered to 1 cm below the level of fluid in the neck of the flask. Additional water is added if necessary. 4) The flask is allowed to stand at room temperature for several hours in subdued light. 5) detect the presence of free-swimming miracidia. The typical miracidium is a tiny, ciliated organism. It is long round form. Miracidium swims ceaselessly during its short life. Free-swimming miracidia are very active, although the miracidia do not have eyespots, they apparently have photoreceptors, and they are positively phototrophic
TAPEWORM: Taenia solium, Taenia saginata, Spirometra mansoni echinococus granulosus Objectives and requirements To study the general morphology and characteristics of life cycle of tapeworm 2. To study the diagnostic methods and morphological comparison between these tapeworms dangerous of taeniasis, cysticercosis, hydatid disease and sparganosis to human being 4. To study the morphology of hydatid cyst of E granulosus Observation and experiment 1. Taenia Solium and Taenia saginata (1)Adult worm A. See the preserved specimen of T. solium(Demonstration) B. See the preserved specimen of T. Saginata(Demonstration) Note the size, ribbon shape, scolex and segmer D. Observe the stained specimen of scolex of T solium(Manipulation Spherical, four suckers, with rostellum armed with two rows of hooklets, numbering E. Observe the stained specimen of scolex of T saginata( Manipulation Quadrate, four suckers, no rostellum or hooklets What are the differences between the scoleces of these two tapeworms? E. See the stained specimen of segment of T solium(Demonstration) F. See the stained specimen of segment T saginata(Demonstration) Note each segment has 2 full sets of reproductive organs, one of male and another female. The testes are follicular, about 100 in number. Ovary with two lobes (T saginata) or three lobes(T solium). Uterus club shaped. No digestive tract G. Observe the ink-stained specimen of gravid segment of T solium(Demonstration) Count the number of lateral branches of uterus on one side. 7-13 lateral branches on each side of uterus unequal in length H. Observe the ink-stained specimen of gravid segment of T. saginata(Demonstration Count and compare the number of lateral branches with that of T. solium. 15-30 I. Observe the preserved specimen of tapeworm(Demonstration) Press a gravid segment between two slides, examine and count the number of lateral
16 TAPEWORM: Taenia solium, Taenia saginata, Spirometra mansoni & Echinococus granulosus Objectives and Requirements 1. To study the general morphology and characteristics of life cycle of tapeworm. 2. To study the diagnostic methods and morphological comparison between these tapeworms. 3. To understand the dangerous of taeniasis, cysticercosis, hydatid disease and sparganosis to human being. 4. To study the morphology of hydatid cyst of E. granulosus. Observation and Experiment 1. Taenia Solium and Taenia Saginata. (1) Adult worm A. See the preserved specimen of T. solium (Demonstration). B. See the preserved specimen of T. Saginata (Demonstration). Note the size, ribbon shape, scolex and segmentation. D. Observe the stained specimen of scolex of T. solium (Manipulation). Spherical, four suckers, with rostellum armed with two rows of hooklets, numbering 25～30. E. Observe the stained specimen of scolex of T. saginata (Manipulation). Quadrate, four suckers, no rostellum or hooklets. What are the differences between the scoleces of these two tapeworms? E. See the stained specimen of segment of T. solium (Demonstration). F. See the stained specimen of segment T. saginata (Demonstration). Note each segment has 2 full sets of reproductive organs, one of male and another female. The testes are follicular, about 100 in number. Ovary with two lobes (T. saginata) or three lobes (T. solium). Uterus club shaped. No digestive tract. G. Observe the ink-stained specimen of gravid segment of T. solium (Demonstration). Count the number of lateral branches of uterus on one side. 7～13 lateral branches on each side of uterus unequal in length. H. Observe the ink-stained specimen of gravid segment of T. saginata (Demonstration). Count and compare the number of lateral branches with that of T. solium. 15～30 lateral branches, equal in length. I. Observe the preserved specimen of tapeworm (Demonstration) Press a gravid segment between two slides, examine and count the number of lateral
branches under lower-lens microscope J. See the SEM of T solium scolex(Demonstration) (2)Larva A. Study the stained specimen of cysticercus cellulose Note the rostellum hooklets. sucker and bladder B. See the stained specimen of cysticercus bovis and compare with the scolex of cysticercus cellulose(Demonstration C. See the preserved specimen of cysticerci(Demonstration) D. See cysticercus bovis in cardiac muscle of ox(Demonstration) E. See cysticercus cellulose in cardiac muscle of pig(Demonstration) (3)Ovum(Manipulation) Observe the live specimen of taenia ova. Note the size, color, characteristics of embryophore and contents of the ova. Nearly spherical, eggshell is easily ruptured Materials examined: feces or swab of anus 2. Spirometra mansoni A. See the preserved specimen of adult worm. B. Study the stained specimen of adult worm Note globular testes(over 300-500 in number)in the lateral margins of dorsal side, C. See the stained specimen of scolex D. See the SEM photograph of S. mansoni scolex (2)Larva and intermediate hosts(Demonstration) A. See the procercoid B. Observe the live spargana in frog flesh. Note the spargana lodging in muscles, they are long whitish worms. The scolex is similar to that of adult, body unsegmented C. See the first intermediate host cyclop and second intermediate host frog (3)Ovum Study ova of S. mansoni. Note its spindle shape, operculum, thin shell, and a germinal cell with numerous yolk granules (4)Dissection of frog for sparganum(Students work in groups Sacrifice the frog by destroying the spinal cord with a small drill. Fix the frog on a board ventral side up. Make a midline incision on the abdominal wall. Skin it and search the flesh for spargana 3. Echinococus granulosus (1)See the stained specimen of adult worm(Demonstration)
17 branches under lower-lens microscope. J. See the SEM of T. solium scolex (Demonstration). (2) Larva A. Study the stained specimen of cysticercus cellulose. Note the rostellum, hooklets, sucker and bladder. B. See the stained specimen of cysticercus bovis and compare with the scolex of cysticercus cellulose (Demonstration). C. See the preserved specimen of cysticerci (Demonstration). D. See cysticercus bovis in cardiac muscle of ox (Demonstration). E. See cysticercus cellulose in cardiac muscle of pig (Demonstration). (3) Ovum (Manipulation) Observe the live specimen of taenia ova. Note the size, color, characteristics of embryophore and contents of the ova. Nearly spherical, eggshell is easily ruptured, only embryophore is seen. Materials examined: feces or swab of anus. 2. Spirometra mansoni (1) Adult worm (Demonstration) A. See the preserved specimen of adult worm. B. Study the stained specimen of adult worm. Note globular testes (over 300～500 in number) in the lateral margins of dorsal side, and two lobulated ovary and overlapping uterus in the mid-portion of the segment. C. See the stained specimen of scolex. D. See the SEM photograph of S. mansoni scolex. (2) Larva and intermediate hosts (Demonstration) A. See the procercoid. B. Observe the live spargana in frog flesh. Note the spargana lodging in muscles, they are long whitish worms. The scolex is similar to that of adult, body unsegmented, strong motility. C. See the first intermediate host cyclop and second intermediate host frog. (3) Ovum Study ova of S. mansoni. Note its spindle shape, operculum, thin shell, and a germinal cell with numerous yolk granules. (4) Dissection of frog for sparganum (Students work in groups). Sacrifice the frog by destroying the spinal cord with a small drill. Fix the frog on a board ventral side up. Make a midline incision on the abdominal wall. Skin it and search the flesh for spargana. 3. Echinococus granulosus (1) See the stained specimen of adult worm (Demonstration)