Day 7: Protozoan Parasites

Question 1

What is the phylum of Protozoan Parasites called

Answer 1

Sarcomastigophora

Question 2

What is the subphylum of Protozoan parasites called

Answer 2

Apicomplexa

Question 3

Where do protozoas replicate

Answer 3

Protozoas replicate inside the host cells
Cells are damaged when parasites leaves the cell
This leaves the gut open to other pathogens

Question 4

What is merogony

Answer 4

Also called schizogony
Asexual division
Multiple asexual division to give many merozoites

Question 5

What is the generalized life cycle of Protozoa

Answer 5

Asexual division
Sexual division
Sporogony

Question 6

What is the single host epidemiology

Answer 6

Poor sanitation
Poor management
Overcrowding
Moisture
Carriers (Older animals are asymptomatic but contaminate young)
Extreme resistance of oocysts in environment
Fomits
Insects and bird carriage

Question 7

What are the clinical signs of cyst forming coccidia

Answer 7

Diarrhea
Fever
Inappetence
Weight loss
Emaciation
Death in extreme cases

Question 8

What is the pathology of Cyst forming coccidia

Answer 8

Emergence of the merozoites causes cell lysis of intestinal epithelium
Hemorrhage into the lumen of the intestine
Catarrhal inflammation

Question 9

What is the species for bovine coccidiosis called

Answer 9

Eimeria bovis
Eimeria zuernii

Question 10

How many hosts does Bovine coccidiosis have

Answer 10

One

Question 11

How do you control Bovine coccidiosis

Answer 11

Feed lot operations
Range cattle

Question 12

What is feline/canine coccidiosis species called

Answer 12

Isospora in dogs, cats, most carnivores and birds

Question 13

What is the clinical signs of feline/canine coccidiosis?

Answer 13

Common in kennels
Uncommon in general
Bloody diarrhea
Weight loss
Dehydration

Question 13

How many hosts do feline/canine coccidiosis have

Answer 13

One

Question 14

What is the epidemiology of feline/canine coccidiosis

Answer 14

Usually seen in a kennel situation
Oocysts extremely resistant to sanitation
Oocysts are difficult to eliminate once present

Question 15

What is the most prevalent coccidia in calves <1 month

Answer 15

Cryptosporidium parvum
Cryptosporidium muris

Question 16

How many hosts are in calf coccidia

Answer 16

One

Question 17

What is the morphology of Cryptosporidium

Answer 17

Found in the mucosal brush boarder in the small intestine
Very small size

Question 18

What are the clinical signs for Cryptosporidium

Answer 18

Abdominal pain
General discomfort
Diarrhea

Question 19

What is the epidemiology of cryptosporidium

Answer 19

Most infected calves shed oocysts in their feces before 1 month of age
Infection occurs by fecal-oral contamination

Question 20

Is cryptosporidium zoonotic

Answer 20

Yes
It infects many animal species including humans
Cattle are the major source of human infection through contamination of aquifers
Self-limiting disease in humans resembling influenza unless there is immune compromise

Question 21

Which cyst forming coccidia has two hosts

Answer 21

Toxoplasma gondii

Question 22

What is the definitive hosts of toxoplasma gondii

Answer 22

Wild and domestic cats are the only known definitive hosts

Question 23

How do cats acquire toxoplasma gondii

Answer 23

Carnivorism-Ingestion of raw meat fed by owners
Ingestion of contaminated feces
Congenital infection

Question 24

Who are intermediate hosts of toxoplasma

Answer 24

Infect all warm-blooded mammals including humans

Question 25

What is entero-epithelial in toxoplasma gondii

Answer 25

Toxoplasma gondii Occurs only in cats Ingestion of tissue cyst by cat releases bradyzoites Bradyzoites penetrate epithelial cells in gut and replicate asexually Sexual reproduction with gametocytes produces oocytsts Oocysts are passed in feces Oocysts sporulate in environment Oocysts are small

Question 26

What is the extra-intestinal life cycle of toxoplasma gondii

Answer 26

Occurs in intermediate hosts Ingestion of infective tissue cyst or oocyst Bradyzoites penetrate intestines and spread to other organs Multiply in cells until the cell is destroyed Repeat replication and eventually encyst in brain, heart, skeletal muscle, visceral organs

Question 27

What is the stage for tissue damage

Answer 27

Tachyzoite Particularly in young animals

Question 28

What are the clinical signs of toxoplasma gondii

Answer 28

Clinical disease is rare Puppies, piglets and kittens Fever Anorexia Cough and dyspnea Diarrhea Jaundice CNS dysfunction Chorioretinitis on a fundic exam

Question 29

What happens in sheep, goats, and pigs with toxoplasma

Answer 29

Abortion

Question 30

What is the pathology of toxoplasma

Answer 30

No gross lesion (usually) but inflammation Fetal brain often has focal areas of nonsuppurative inflammation on histology Postmortem examination Onset of immunity tachyzoites localize as tissue cysts in neural and muscular tissue

Question 31

What is the zoonosis symptoms of toxoplasma gondii

Answer 31

Cause serious problems in unborn children and babies 30-40% adults infected Humans infected early in life may have recrudescence Serious disease in immunosuppressed individuals (AIDS-defining disease) Congenital infection occurs when tachyzoites are transmitted across the placenta from mother to child

Question 32

What is the cyst forming coccidia in Opossum called

Answer 32

Sarcocystis neurona

Question 33

Who are the intermediate hosts of of sarcocystis

Answer 33

Cats, raccoons, skunks, armadillos, harbor seals, brown-headed cowbirds, sea otters, horses and others Majority of horses are exposed at an early age

Question 34

What is the lifecycle of Sporozoan in the Sarcocystis species

Answer 34

Develops in 2 host-cycles Intermediate host (prey) Final host (predator) Transmission to definitive host is by ingestion of meat with sarcocysts

Question 35

What are clinical signs of sarcocystis in horses

Answer 35

Equine Protozoal Meningoencephalitis (EPM) Gait abnormalities Circling Dysphagia Difficult to diagnose lameness

Question 36

What is the most common cause of bovine abortion in the US

Answer 36

Cyst forming coccidia-neospora caninum Found world-wide

Question 37

How many hosts does Neospora caninum use

Answer 37

Two

Question 38

What is the host range in Neospora caninum

Answer 38

Dogs, cattle, sheep, and horses

Question 39

What is the transmission of Neospora caninum

Answer 39

Fecal-oral from dog to cattle Transplacental transmission