Quiz 2 (Protozoa & Arthropods)

Question 1

4 Main Phylums of Protozoa

Answer 1

1. Sarcomastigophora
2. Apicomplexans
3. Ciliophora
4. Microspora

Question 2

Protozoan Nutrition

Answer 2

Autotrophic

Heterotrophic (Holozoic (ingests via mouth) or Saprozoic (absorbs through cell membrane))

Question 3

Sarcomastigophora species

Answer 3

Giardia spp.
Trichomonads (Tritrichomonas foetus (cattle), Tritrichomonas blagburni (felids), Tetratrichomonas spp./Pentatrichomonas hominis (non-pathogenic bovine trichomonads))
Trypanosomes (Trypanosoma cruzi)

Question 4

Apicomplexan species

Answer 4

Order Eucoccidia: E. bovis and E. zuernii
Cystoisospora suis
Cryptosporidium (Toxoplasma gondii and Sarcocystis cruzi)
Oder Piroplasmidia: Cytauxzoon felis

Question 5

Giardia spp.

Answer 5

Direct life cycle
Most mammals (ingestion of cyst, longitudinal binary fission)
Cysts: 4 nuclei, Trophozoites: 2 nuclei
Clinical signs: diarrhea, or asymptomatic
Dx: Fecal float, direct smear, ELISA

Question 6

Trichomonads

Answer 6

Flagella, undulating membrane, axostyle
Psuedocysts
Longitudinal binary fission
Includes Bovine Genital Trichomonosis (T. foetus) and Feline Trichomoniasis (T. blagburni)

Question 7

Tritrichomonas foetus

Answer 7

Bovine Genital Trichomonosis
Can cause early embryonic death and abortion
Bulls are asymptomatic
Cows: vaginitis, etc.
Dx: recover organisms -> PCR, direct smear, culture
Prevention: replace old bulls, don’t borrow/lease animals, TEST, cull open cows, etc.

Question 8

Non-pathogenic Bovine Trichomonads

Answer 8

Pentatrichomonas hominis

Tetratrichomonas spp.

Question 9

Tritrichomonas blagburni

Answer 9

Feline Trichomoniasis
Large bowel disease
Transmission unknown
Chronic diarrhea
Dx: direct smear, culture, PCR, colonic biopsy
Control: keep infected cats away from others, clean litterbox daily

Question 10

Trypanosoma cruzi

Answer 10

Parasite of all vertebrates, transmitted by blood-feeding invertebrates
Have kinetoplast and nucleus
Pleomorphic: elongated body with single flagellum (trypomastigote, promastigote, epimastgote) or round body with short (if any) flagellum (amastigote)
Cytoskeleton with microtubules
Chagas Disease (Reduviid Bug)
INFECTIVE STAGE = metacyclic trypomastigote

Question 11

“Classical Coccidia”

Answer 11

Eimeria and Cystoisospora

Question 12

Eimeria and Cystoisospora differences

Answer 12

Eimeria: mammals + BIRDS, 4 sporocytes w/ 2 sporozoites
Cystoisospora: only mammals, 2 sporocytes w/ 4 sporozoites

Question 13

Eimeria bovis

Answer 13

Affects ileum and colon of cattle
Reproduce by gametogony
Easier to diagnose
Oocysts present when disease begins
Mucosal damage

Question 14

Eimeria zuernii

Answer 14

Affects ileum and colon of cattle
Reproduce by schizogony
Bloody diarrhea, anemia, emaciation
Acute and chronic phases

Question 15

Cystoisospora suis

Answer 15

Pigs
Primary disease of suckling piglets, contaminated feces
Sporozoites penetrate villous epithelium
Pasty/liquid diarrhea, NO BLOOD

Question 16

Cryptosporidium

Answer 16

Affects intestine (profuse yellow, watery diarrhea)
Fecal-oral transmission
Waterborne outbreaks: Milwaukee 403,000 affected,104 deaths
Oocyte resistance: Heat (64-72 degrees C), UV, chlorine, bleach, water treatments

Question 17

Toxoplasma gondii

Answer 17

Obligate, intracelluar parasite
IH: most mammals (tachyzoites, bradyzoites), DH: felids (oocysts)
Transmission: ingesting oocyts, raw/undercooked meat, or congenital (transplacental)
Clinical signs: fever, anorexia, jaundice
Dx: fecal float, IFA, ELISA, Bx, PCR

Question 18

Sarcocystis spp.

Answer 18

DH: carnivore, IH: herbivore
Transmission: DH consuming IH with sarcocyst, IH ingesting sporocyst
Gametogony
Schizonts form in endothelial cells of blood vessels

Question 19

Sarcocysts cruzi

Answer 19

Dalmeny Disease in cattle (fever, weightloss, diarrhea, etc.)
Equine Protozoal Myeloencephalitis in horses (head tilt, eye drooping, facial paralysis)- schizonts destroy neural cells, no sarcocysts

Question 20

Cytauxzoon felis

Answer 20

Piroplasmida
Reservoir: bobcat
DH: domestic cats
IH/vector: salivary glands of ticks
Schizogony occurs in macrophages of cats, merozoites released when macrophage ruptures and enter RBC and develop to piroplasms
Fatal and non-fatal forms
**Schizogenous stage is most destructive

Question 21

Lifecycle of Trypanosomes

Answer 21

1. Metacyclic trypomastigote = infective stage in feces
2. Trypomastigotes: circulate in blood, go to organs/muscle
3. Amastigote: in cells, reproduce via binary fission, clusters produce psuedocysts, rupture
4. Epimastogotes: reproduce via binary fission

Question 22

Coccidias (Order Eucoccidia)

Answer 22

Eimeria
Cystoisospora
Toxoplasma
Neospora
Cryptosporidium
Sarcocystis

Question 23

Characteristics of Protozoa

Answer 23

~60,000 species
Eukaryotic, single-celled
Have organelles of locomotion

Question 24

Characteristics of Insecta

Answer 24

Segmented body (head, thorax, abdomen)
Simple or complete metamorphosis
Includes: Anoplura (sucking lice), Mallophaga (chewing lice), Diptera (2 winged flies), and Siphonaptera (fleas)

Question 25

Characteristics of Arachnida

Answer 25

2 body regions: head (gnathosoma/capitulum) and body (idiosoma) Simple metamorphosis Includes: Acarina

Question 26

Diptera

Answer 26

Myiasis: facultative or obligatory Includes: Culicidae (mosquitos), Tabanidae (horse and deer flies), and Muscidae (stable flies)

Question 27

Culicidae

Answer 27

Mosquitos Most prominent blood-sucking parasite Larvae: always aquatic, complex metamorphosis, spiracles Antennae: female- pilose, male- plumose Includes subfamilies Anopheles, Aedes, and Culex

Question 28

Anopheles

Answer 28

``` Plasmodium vector Eggs: single with floats Larva: No air tube Pupa: short air tube Adult: resting position is ANGLED ```

Question 29

Aedes

Answer 29

Eggs: single on dry surface Larva: short air tube at angle to water surface Pupa: air tube variable Adult: resting position parallel to host

Question 30

Culex

Answer 30

Vector for Yellow Fever, Dengue Fever, West Nile Virus Eggs: rafts parallel to water surface Larva: short air tube at angle to water surface Pupa: air tube long and slender Adult: resting position parallel to host

Question 31

Tabanidae

Answer 31

Horse and deer flies Found where water is abundant Eggs laid on vegetation near water ->larvae hatch and enter water (tabanus = predators, chrysops = vegetarians) ->larvae pupate on dry ground along bank -> Adults emerge IH: trypanosoma, elaeophora Vectors: anaplasma, anthrax, Equine Infections Anemia

Question 32

Muscidae

Answer 32

Stable flies (Stomoxys calcitrans) Males AND females are blood feeders Mechanical vector for bacteria, Equine Infectious Anemia, Habronema muscae, Trypanosoma evansi Eggs deposited, hatch, larva pupate in dead plant matter Control: insecticides, remove rotting straw/plant matter

Question 33

Anoplura

Answer 33

Sucking lice Mammals only Thorax is wider than head

Question 34

Mallophaga

Answer 34

Chewing/biting lice Found on mammals and birds Head is wider than thorax

Question 35

Siphonaptera

Answer 35

``` Fleas Ctenocephalides felis (cat flea) 40% of veterinary effort Host-specific 95% of lifecycle spent off host *sperm stored in spermatheca during mating ```

Question 36

Acarina

Answer 36

Ticks and mites 2 families: Ixodidae and Argasidae Eggs-> larva ("seed tick")-> nymph -> adult Disease transmission (transstadial and transovarial) Tick paralysis

Question 37

Ixodidae

Answer 37

``` Inclues: Rhipicephalus sanguineus ("Brown Dog Tick") Ixodes scapularis ("Black-legged Tick") Amblyomma americanum ("Lone Star Tick") Dermacentor variabilis ("American Dog Tick"/"Wood Tick") ```

Question 38

Flea control methods

Answer 38

Host-targeted insecticides Environmental insecticides Mechanical methods

Question 39

Brown Dog Tick

Answer 39

Rhipicephalus sanguineus 3 host tick Disease vector for babesia, erlichia canis All over US

Question 40

Black-legged Tick

Answer 40

Ixodes scapularis 3 host tick SE to central US and along E coast

Question 41

Lone Star Tick

Answer 41

Amblyomma americanum 3 host tick Tick paralysis Southern US

Question 42

American Dog Tick/ Wood Tick

Answer 42

Dermacentor variabilis 3 host Most of US Vector for RMSF and anaplasma

Question 43

Ear mites

Answer 43

``` Otodectes cynotis External ear canal Females: suckers on legs 1,2,4 Males: suckers on all leg pairs Permanent parasite Transmission through direct contact NOT ZOONOTIC Ear swab ```

Question 44

Follicle mites of dogs

Answer 44

``` Demodex canis Alligator/cigar shaped Adults- 8 legs, larva- 6 legs permanent parasite Localized and generalized parasitism Dx: skin scrape, pustule/abscess contents NOT ZOONOTIC ```

Question 45

Scabies

Answer 45

Sarcoptes scabiei Host: most mammals Tunnel through dermis causing scaling, excoriations, pruritis Eggs/feces are allergens, can cause hypersensitivity Female- suckers on legs 1,2 Males- suckers on legs 1,2,4

Question 46

Water treatments effective against crypto

Answer 46

``` Reverse osmosis Distilled Steaming hot Pastuerized Canned/bottled Filtered less than 1 micron ```