ANIMAL PARASITOLOGY LAB. BIOL 4426L

LAB. #5.

Flatworms

Phylum Platyhelminthes

Class Trematoda

Subclass Digenea

Study question: What features distinguish the Digenea from all other organisms?

Family Fasciolidae (Text pages 253-259)

Fasciola hepatica B (Text pages 253-257)

Slide: whole worm,

- Locate the anterior part of the worm. What shape do you see?

- What attachment organ is present on the anterior of the parasote?

- Locate the acetabulum or ventral sucker. Where is it in relation to the

oral sucker?

- Locate and identify the ovary and the testes

- Can you distinguish the intestinal cecae and vitellaria?

Slide: eggs

- What shape are these eggs?

- Locate the operculum or ALid@

- What can you see inside the egg?

Slide: miracidium,

- What is the shape of this stage?

- Locate the anterior end. What features or organs can you distinguish?

- Where would you find this stage?

Slide: rediae,

- Locate the anterior end. What distinctive feature do you see?

- Locate the posterior end. What features or organs can you distinguish?

- Can you see germinal cells?

- Where would you find this stage?

Slide: cercaria

- What features of the cercaria distinguish it?

- Where would this stage be found?

- Distinguish this cercaria from the cercaria of Schistosoma

Slide: metacercaria

- Locate the oral and ventral suckers, cecae, and excretory bladder.

- Where is this stage found?

Study questions: What morphological feature distinguishes the adult of this worm?

How is it different from the following worm?

In what host are the rediae found? the metacercaria?

How can a human become infected with this parasite?

Where in the body are the mature worms found? How did they get there?

Fasciola magna B Whole worm (Text pages 257-258)

- Where did this worm come from?

- What distinguishes it from Fasciola hepatica?

- What morphological feature distinguishes this worm?

- How is this worm different from Fasciola hepatica?

Family Opisthorchiidae (Text pages 273-277)

Clonorchis sinensis B (Text pages 273-277)

Slide: whole worm

- Locate the oral and ventral suckers

- Locate the ovary, uterus, testes, vitellaria, intestinal cecae.

Slide: egg

- What two features distinguish this egg from all others?

Study questions: What is the common name of this worm?

What morphological features distinguish this worm?

Where is this worm found?

What is the lifecycle of this parasite?

Family Schistosomatidae (Text pages 236-248)

Schistosoma mansoni B (Text pages 236-246)

Slide: whole male

- Locate the oral and ventral suckers

- Locate and count the Testes. How many are there?

- What is the size of this worm?

- Can you see bumps over the body of the worm?

Slide: whole female

- Locate the oral and ventral suckers

- Locate the ovary. Where in the body of the parasite is it?

- What is the size of this worm compared to the male?

Slide: male and female in copula

- Which worm is the male and which is the female?

- What is the structure called that holds one of these worms?

- Where in the host would these worms be found?

Slide: eggs

- What features distinguish this egg from all others?

Slide: cercaria

- What feature distinguishes these from all other cercariae?

- What host does this cercaria infect?

Slide: eggs in human liver section (granuloma)

- Locate the eggs in the tissue.

- What host reaction do you see in the tissue?

Study questions: What disease does this parasite cause?

What is the in copula position in these worms?

What happens when the female is ready to lay eggs?

How do these eggs get out of the hosts' body and into the environment?

What feature of the eggs supposedly aids in this journey?

How is the life cycle of this species different from that of Fasciola?

Why are there eggs in the liver when they are supposed to pass out of the intestine?

How can you distinguish this species from the other two species of Schistosoma?

Schistosoma haematobium B B (Text pages 236-246)

Slide: egg

- What feature distinguishes these from all others?

- Where would these eggs be found in the host?

Schistosoma japonicum B (Text pages 236-246)

Slide: egg

- What feature distinguishes these from all others