Practice Lab Exam

Question 1

A goldfish presents to your office with small pustular lesions throught its epidermis and gills. What is the name (common or scientific genus) of the parasite causing the lesions?

Answer 1

Ich

Ichthyophthirius

Question 2

Which life stage is found in the lesion?

Answer 2

Trophozoites

Live in galleries in the skin of fish

Question 3

This protozoan is commonly found in the swine gut, but it can cause dysentery-like symtpoms in apes and humans. What is the genus of this parasite?

Answer 3

Balantidium (coli)

Question 4

This is a life stage of a coccidian. What name is given to this stage?

Answer 4

Oocyst

Question 5

Which of the following animals was the definative host… a cat or a llama?

Answer 5

You can see 2 sporocysts

= Isospora

= cat

(Remember Eimeria has 4 sporocysts)

(E = IIII) (I = II)

(Emieria = chickens & ruminants)

Question 6

These parasites were found in ovine (sheep) bile ducts. Are these parasites tapeworms, flukes, nematodes, or acanthocephalans?

Answer 6

Flukes

(Fasciola hepatica)

Question 7

Is the transmission the same for both parasites?

Answer 7

No!

Flukes: ingest snail while grazing

Tapeworms: ingest eggs or infected insects/animals

Nematodes: ingest eggs

Acanthocephalans: ingest eggs

Question 8

This parasite was found in the gut of a duck. What is the genus of this parasite?

Answer 8

Echinostoma

Question 9

After preforming a fecal floatation exam on a horse, you find many of these eggs. What is the genus of the parasite that produced these eggs?

Answer 9

Anoplocephala

(Tapeworm)

Question 10

What is the intermediate host for the eggs in Q9? What is the larval stage of this parasite called in the IH?

Answer 10

Oribatid mites (pasture mite)

Cysticercoid (larval stage of tapeworms)

Question 11

A client brings in their dog into the clinic after this parasite was seen protruding from the dog’s anus. The client, an avid fisherman, admits that he routinely gives his dog raw pieces of fish. What is the genus of this parasite?

Answer 11

Diphyllobothrium (latum)

DH: Bear, human, dog

IH: Copepod & pike

Question 12

What is the intermediate host of this parasite from Q11?

Answer 12

Copepod & Fish (pike)

Two IHs!

Question 13

You are called out to a small “mom and pop” range poultry operation because the owners report serious losses. The owners have noticed that the birds are having difficulty breathing. You nectropsy a few birds and see the following lesions in the trachea. What parasite is causing the disease?

Answer 13

Syngamus trachea

Gapewrom or Y-worm

Question 14

How are these birds in Q13 becoming infected? Two ways.

Answer 14

1. Ingestion of earthworms (paratenic host)
2. Direct ingestion of eggs

Question 15

You have been called out to a small farm. Your client’s chief complaint is that her old warmblood has had some serious coughing. You notice that the horse is in the same corral as a donkey. When you ask the client about the donkey, she responds that she bought the donkey several months ago to keep her horse company. What parasite may be causing the horse’s condition?

Answer 15

Dictyocaulus arnfieldi

(Donkey lungworn)

Question 16

What diagnostic test would you run on the horse’s feces in order to verify the presence of the parasite in Q15?

Answer 16

Baermann examination of feces (larvae)

NO eggs in feces!

Question 17

You visit a small pig operation where several pigs have been coughing. After running a fecal float (on fresh feces), you see the following. What parasite is infecting these pigs?

Answer 17

Metastrongylus apri

(Larvated egg in fresh swine feces)

Question 18

How are the pigs becoming infeced in Q17?

Answer 18

Pigs eat earthworms

Question 19

You see a few lesions by the mucocutaneous junction of the upper lip of a horse. The lesion is chronic granulomatus and has not healed. You examine some scrapings of the lesion and see what appear to be nematode worms. What parasite is likely causing the lesion?

Answer 19

Habronema

Question 20

Where in the horse do the adult forms of the parasite in Q19 live?

Answer 20

Stomach

(Horse stomach worm)

Question 21

You see the following on a cat fecal. What two species (not genus) do you see?

Answer 21

1. Toxascaris leonina

(lighter, more space w/ smooth shell)

2. Toxocara cati

(dark w/ rough shell)

Question 22

What is the genus of this parasite?

Answer 22

Trichuris

Question 23

Which egg would the female produce in Q22?

Answer 23

B

Bipolar plugs, thin wall, colorful

Question 24

You see these eggs on a sheep fecal.

a) Name the two genra that could have produced the most commonly observed type of egg
b) Name the genra of the large egg
c) Name the genra of the egg in the bottom right corner

Answer 24

a) Haemonchus & Trichostrongylus (HOT)
b) Nematodirus
c) Trichuris

Question 25

You see these two distinct parasites on a dog fecal exam. Name the two genra in which the dog is the definitive host.

Answer 25

1. Ancylostoma 2. Isospora

Question 26

Answer 26

A. Dermanyssus

Question 27

Answer 27

Echidnophaga

Question 28

This parasite was found in a horse's stomach during necropsy. What is this parasite's genus?

Answer 28

Gastrophilus

Question 29

These respiratory structures are used to identify maggots. What are they called? Are they the anterior or posterior end of the maggot?

Answer 29

Spiracles Posterior

Question 30

These two ticks were found on a dog. The dog is the principal host for both species adults. What are their specific names (genus and species)?

Answer 30

1. Dermacentor variabilis (american dog tick) 2. Rhipicephalus sanguineus (brown dog tick)

Question 31

What common name is given to the parasite groups for the organisms listed below?

Answer 31

Sucking lice Chewing lice

Question 32

What apparatus is unique to McMaster's exam?

Answer 32

Special slide for fecal egg counts