Vocab/Parasite Info Flashcards

Question

Homo/monoxenous

Answer 1

Only 1 host (definitive).

Answer 2

Lice infestation

Answer 3

* Characteristic of nematodes * Release egg w/ single L1 larvae * Ex. *Strongyloides westeri*

Answer 4

* Phylum platyhelminthes * "Flukes" * All parasitic * Endoparasites

Answer 5

Ideally, parasite does not want to kill host (aka it's food source)

Answer 6

* Phylum platyhelminthes * Class trematoda * IH: aquatic snail * DH: Dog, bobcat, raccoon * Often asymptomatic * D/V, wt. loss, lethargy, hypercalcemia, skin irritation, inflammation * Target organs: mesenteric & hepatic veins * Dioecious * "Swimmer's itch" (cercarial dermatitis) in humans

Answer 7

Prelarval stage of *Dirofilaria immitis *(heartworm) found circulating in blood

Answer 8

* Maturing infection, Mff not yet in circulation * Use of preventative or microfilaricide w/ out removing adult worms * Unisex/Occult (female) infection * Dog's immune system responds to Mff's * Failure to use Mff concentration test

Answer 9

* Phylum protista * Direct life cycle * DH: most mammals, birds, amphibians * Vegetative stage: * 2 nuclei * 8 flagella * Ventral groove * Looks like smiley face * In loose feces * Cyst stage * resistant * in normal feces * 4 nuclei

Answer 10

Flea infestation

Answer 11

* Chronic - villus atrophy * Intermittent diarrhea * loose * mucoid, not watery * Majority are asymptomatic

Answer 12

* Characteristic of nematodes * Releases egg with single stage or morula * Ex. *Haemonchus contortus*

Answer 13

* Kingdom protista * DH: cats (esp. younger) * No known IH, transmission unknown * Large-bowel disease * chronic diarrhea * spontaneous resolution * relapse * tenesmus * flatulence * Anal irritation * Fecal incontinence

Answer 14

"Stable Fly" * Phylum arthropoda * Class insecta * Order diperta * Family muscidae * Hosts: domestic animals, humans * **Males and Females feed on blood** * Mechanical vector * Terrestrial larvae (decaying plant material) * Affected by insecticides

Answer 15

* Treat Mff * macrocyclic lactone @ sufficient dosage * minimize potential for resistance development * monitor for anaphylaxis * minimize spread of disease within 1 mile radius * Retest for heartworm 6 mos. post-treatment

Answer 16

Mff never dissappear completely from peripheral blood at some point in 24 hr period (Dirofilaria immitis, heartworm)

Answer 17

* Phylum nematoda * Medium-sized * Large mouths * Prominent copulatory bursa (males) * Direct life cycle * often extensive larval migration * Non-larvated eggs in feces

Answer 18

* Kingdom protista * Phylum apicomplexa * Order Eucoccidiida * Stenoxenous * Monoxenous (direct life cycle) * DH: dogs, cats, pigs, humans (esp. AIDS patients) * Sexual & asexual reproduction * Oocyst - 2 sporocysts w/ 4 sporozoites each

Answer 19

Class 1, 2: Fast kill * Admin deep IM injection twice, 24 hrs apart * Rest 1 mos. post-final treatment Class 3: Slow kill * Admin single dose immiticide, followed in 1 mos. by 2 injections of immiticide, 24 hrs apart * Rest 1 mos. post-final treatment Caval syndrome * sx removal of heartworm from RA (don't break them! can induce major allergic response!!) * slow kill treatment Pain management for deep IM injections

Answer 20

* Phylum arthropoda * 2 body regions * head * body * Simple metamorphosis

Answer 21

Severe * Unstable animal * Poor prognosis * Cardiac cachexia (wasting) * Constant fatigue * Persistent cough * Dyspnea * +/- signs of R sided heart failure * Acites * Jugular vein distention (JVD) * Anemia ( * Proteinuria (\>2+) * Rad signs * RV +/- RA enlargement * PA enlargement * Pulmonary thromboembolism (PTE) * Adult worms detected in echocardiogram

Answer 22

* Zoonosis of canine ascarid in humans (paratenic host) * children that eat dirt * Chronic granulomatous lesions * often in lier, lungs, brain (NLM), eye (OLM) * Hepatomegaly * Wt. loss * Dec. appetite * Persistant cough

Answer 23

Mff released by female worm → Mff enter circulation → Mosquito feeds on infected dog → Mff become L3 → Mosquito feeds on other dog, infects it with L3 → L3 molts during migration to heart & lungs → Adult worms mature in heart & lungs → Adult worms mate → produce Mff Prepatent period: 5.5-7 mos

Answer 24

Capable of living either free or as a parasite

Answer 25

* Kingdom protista * Distinct nucleus * Move via flagella * Asexual repro. * Direct & indirect life cycles

Answer 26

* Phylum platyhelminthes * Class cestoda * Order cyclophyllidea * IH: rabbit, hare * DH: dog * Infected by ingestion of raw/undercooked meat * Metacestode/larvae: cysticercus * Egg: Taeniid type * Hexacanth embryo (oncosphere)

Answer 27

* Phylum nematoda * Superfamily strongyloidea * DH: dog * Target organ: small intestine * 3 pairs of scleritized teeth * Non-embryonated egg shed in feces → embryonates → L1 develops → hatches → molts to L2 → matures to L3, remains ensheathed (no molt!) → infects DH * Black/tarry diarrhea, poor appetite, hemorrhagic pneumonitis * CLM in humans

Answer 28

Involves parasites of companion/food animals

Answer 29

Trypomastigotes passed in feces of IH → enter host via bite wound, scratch, mucus membrane → Trypomastigotes enter circulation → enter cells of spleen, liver, lymphatics, muscle → cell rupture, trypomastigotes remain in circulation OR reinfect → Epimastigotes → replication via binary fission

Answer 30

* Phylum nematoda * Superfamily ascaroidea * DH: dog * Target organ: small intestine * **Egg w/ L2 is infective stage** * Death is rare * Pneumonia, V/D, pot-belly, focal lesions in CNS → neurologic disorders * Zoonotic: VLM

Answer 31

* Kingdom protista * Phylum apicomplexa * Order eucoccidiida * IH: herbivore (ingests sporocysts in DH feces) * Target organs: schizonts in endothelal cells of blood vessels of brain, liver kidney. Form sarcocysts in skeletal & cardiac muscle. * DH: carnivore * Target organ: intestines

Answer 32

time parasite can be detected in host

Answer 33

* 3 host tick * mainly dogs * Tick paralysis * Disease vector * Only tick species to infest homes

Answer 34

* Kingdom protista * Phylum apicomplexa * Order Eucoccidiida * DH: cattle (esp. calves) * Target organ: terminal ileum, colon * Gametogony causes majority of damage * Oocysts present when disease begins * Prepatent period: 5-15 days * Mucosal damage

Answer 35

* Nematode * Hypobiotic L2 in mammary tissue → puppy ingests colostrum → L2 go directly to stomach → small intestine * No migration

Answer 36

* Caused by Trichostrongyloid nematodes * Esp. *Ostertagia ostertagi* * Diarrhea (cattle \> sheep, goats) * Anemia (cattle \< sheep, goats * Bottle jaw * Weanlings at grass are most susceptible * Adults fairly immune * Total eradication unlikely, must move to worm-free pasture

Answer 37

* Strongyloid nematode, L3 * Dogs * Blood/lymphatic vessels → heart → lungs → alveoli → bronchi → swallowed → GI * mature in small intestine * Dogs \>3 mos. * Blood/lymphatic vessels → encyst in muscle (hypobiotic) * Populate mammary glands * Repopulate small intestine

Answer 38

* Strongyloid nematode, L3 * Ingests rodent host * Hypobiotic L3 (no development in rodent) * Adult matures in small intestine * No migration

Answer 39

Too many adult heartworms in R atrium and vena cava. Obstruct blood flow & interfere w/ tricuspid valve closure.

Answer 40

* Phylum arthropoda * Class arachnida * Order acarina * All stages feed on blood * Tick paralysis * Transstadial, transovarial disease transmission * Body division * Head - capitulum * Body - idiosoma (fused cephalothorax & abdomen)

Answer 41

Relationship where one species, the parasite, lives on or in another species, the host, and may cause harm. Parasite is metabolically dependent on host.

Answer 42

* Melarsomine dihydrochloride (Immiticide) * Kills adult worms (nothing younger than L4) * Monthly use of preventatives - "slow kill" * Alternative tx, takes mos. to years to work * Surgical removal of worms

Answer 43

* Phylum arthropoda * Class arachnida * Order acarina * DH: cattle, goats, pigs (most mammals) * Target organ: tunnel through dermid * Eggs/feces can induce hypersensitivity rxn * Long, non-jointed pedicles * Females: suckers on pairs 1, 2 * Males: suckers on pairs 1, 2, 4

Answer 44

* Nematode * Hypobiotic L2 mobilize in late pregnancy → liver of fetus → molt to L3 → in lungs @ birth → alveoli → bronchioles → trachea → coughed up → swallowed → stomach → L4, L5 in small intestines → adult

Answer 45

1 or more intermediate hosts

Answer 46

* Host-targeted insecticides * Kill larvae & adults * Environmental insecticides * Mechanical methods * Vacuum, wash pet bedding * Remove vegetation, litter * Prevent wildlife interaction

Answer 47

* Prevent L3, L4 from maturing * Macrocyclic lactone * Avoid avermectin at first * Kill all Mff at once → major allergic response * Weaken the adult heartworm * Tetracycline * more susceptable to immiticide * Prevent emboli formation * rest until 1 most post-immiticide treatment * Optimize efficacy of immiticide * Allow L5 to become mature adults ## Footnote **IMMITICIDE TOXIC TO CATS**

Answer 48

Ingestion of cyst → excystation in duodenum → replication via binary fission → encystment in lower intestinal tract → infective cysts passed in feces Prepatent period: 1 wk

Answer 49

* Fatal form: * fever (up to 105ºF) * depression, lethargy * anorexia * jaundice * death \< 1 wk * Non-fatal form: * may be asymptomatic * similar signs as fatal form * persistent parasitemia * Schizogenous phase most destructive * Infected macrophages can block blood vessels

Answer 50

* Trematode * Tubular body * Dioecious * Female fits into central groove of male * Mature in blood of DH

Answer 51

* Strongyloid nematode, L3 * Rare transmission, not usually found in nature * No larval migration * Adults mature in small intestine * Prepatent period: 15-18 days

Answer 52

Wide host range

Answer 53

* Hidden infection * Single sex or low number of *Dirofilaria immitis* * Mff not detectable in peripheral blood

Answer 54

* Studies indicate cats shed once (sometimes relapses occur, but rare) * Fever * Anorexia * Jaundice * Ab. pain/discomfort * Hepatitis * Pancreatitis * Neurological problemts * Respiratory interference * Death

Answer 55

* Class cestoda (tapeworms) * Order cyclophyllidea * Larva/metacestode * Single, invaginated scolex * Vertebrate IH

Answer 56

Ticks & Mites * Phylum arthropoda * Simple metamorphosis

Answer 57

* IH (snail): miracidium → Sporocyst → Redia → Daughter rediae/Cercariae * Environment: Cercaria → Metacercaria (infective stage)

Answer 58

Phylum arthropoda Class insecta

Answer 59

Chewing/Biting Lice * Phylum arthropoda * Class insecta * **Head wider than thorax** * Simple metamorphosis * Feed on dead skin * Stenoxenous * Spp. affecting birds, mammals

Answer 60

Bulls (chronic carriers) - often asymptomatic Cows * vaginitis * cervicitis * endometritis * pyometra * mucopurulent discharge * early or late term abortion

Answer 61

* Kingdom protista * Phylum apicomplexa * Order Eucoccidiida * Direct life cycle * DH: pigs (esp. suckling piglets) * Infected via contaminated feces * Pasty/liquid diarrhea (no blood in feces) * Villous atrophy, necrotic enteritis, crypt hyperplasia, secondary infection

Answer 62

Narrow host range

Answer 63

* Phylum nematoda * Short, fat posterior ends * Long, whip-like anterior end * Beaded esophagus (stichocyte) * Usually direct life cycle

Answer 64

* *Trypanosoma cruzi* in dogs * No circulating trypomastigotes (harder to dx) * Dilated, enlarged heart * Arrhythmia * Lethargy * Respiratory difficulties * Anemia

Answer 65

* Blood excreted by adult fleas * Reddish-black pellets in the haircoat * AKA "flea dirt" * Eaten by flea larvae

Answer 66

* Year-round broad-spectrum parasite control for heartworm, intestinal parasites, ticks * Anthelmentic tx every 2 wks until 2 mos. old, then monthly * Maintain pregnant/nursing dams on broad-spectrum control products

Answer 67

* Trematode (digenea) * In snail (IH) * Stage doesn't always occur * Produces daughter rediae or cercariae

Answer 68

Soft-bodied Ticks * Phylum arachnida * Order acarina * Can't see head from dorsal view

Answer 69

* Kingdom protista * Phylum apicomplexa * Order Eucoccidiida * DH: cattle (esp. calves) * Target organ: terminal ileum, colon * Schizogony causes majority of damage * No oocysts present yet (animal typically doesn't live long enough for gametogenesis to occur) * Bloody diarrhea (can "shoot out" when calf coughs) * Mucosal damage

Answer 70

* Phylum arthopoda * Class insecta * "True"/Two-winged flies (includes mosquitoes) * Ectoparasites * Permanant * Temporary * Perform **myiasis** * Complex metamorphosis

Answer 71

* Phylum platyhelminthes * Class cestoda * Order cyclophyllidea * IH: flea, dog louse * DH: Dogs, cats, humans (esp. children) * Target organ: small intestine * Metacestode/larvae: cysticercoid * Armed scolex w/ 4 circular suckers * Egg packets * Prepatent stage: 2-3 wks * Usually not pathogenic, may itch due to migrating proglottids * Heavy infections: constipation, diarrhea, pot-belly

Answer 72

* Strongyloid nematode, L3 * L3's in milk * Hypobiotic larvae migrate to mammary gland * Adult matures in small intestine * No migration

Answer 73

* Massive outpouring of worm eggs (nematode trichostrongyle *H. contortus*) by ewes/does while lactating * Prolactin may suppress immunity to worms * Sources * Hypobiotic larvae resuming development * Ingestion of larvae that have overwintered on pasture * Increased egg output from existing worm population * Worm load maintained rather than expelled → massive pasture contamination of L₃

Answer 74

* Fecal float * ELISA, IFA * 1 pos. serum sample indicates past infetion * 16x rise in titer in serum taken 2-4wks after 1st sample indicates acute, acquired infection * Biopsy * PCR

Answer 75

* *Trypanosoma cruzi *in dogs * Trypomastigotes circulating * Myocarditis * Pale MM * lethargy * Hepatomegaly * Splenomegaly

Answer 76

* Strongyloid nematode, L3 * Rare * L3 in blood stream → placenta → feus * Hypobiotic larvae * Occurs during pregnancy

Answer 77

1. Parasite co-evolved w/ host - began as symbiotic relationship? 2. Parasite has recently colonized the host * more likely to be pathogenic * result of keeping animals in environment to which they are not well adapted

Answer 78

* Heat to 64-72.4°C * Freeze to -20°C * UV irradiation * Chlorine * Hypochlorite * Hydrogen Peroxide * Iodine (not very well) * Does NOT work: * ethanol * isopropanol * Lysol * Pine-sol * formaldehyde * betadine

Answer 79

* Phylum arthropoda * Class arachnida * Order acarina * Larva - 6 legs * Adults - 8 legs * Pedicels - legs/stalks (used to ID) * Body divisions * Head - gnathsoma * Body - idiosoma

Answer 80

* "Roundworms" * Dioecious * Females \> males * Complete digestive system * Cervical alae * Non-segmented * Copulatory bursa (males) - hold onto females * Spicules - equivalent to penis * Mouth possibilities * Sclertotized buccal capsule * Lips * Teeth * Dentigerous ridges

Answer 81

Tick ingests piroplamsm in RBCs of infected host → Piroplasms travel to salivary glands of tick → asexual reproduction → tick feeds on DH → prioplasms develop into schizonts (in macrophages) → merozoites released upon macrophage rupture → enter RBCs → develop into piroplams Transstadial transmission: tick can pick up protozoa in its larval or nymphoid stage and continue carrying the protozoa through its molts

Answer 82

Hard Ticks * Head visible * Scutum * Covers all dorsal part of male * Covern cranio-dorsal part of females * Ornate or inornate * Hypotome - mouthpart * Anal groove * Festoons - wavy ridges on caudal edge

Answer 83

* Phylum nematoda * Female in SubQ * Indirect life cycle * Ex. Guinea worm

Answer 84

* Phylum nemotoda * Superfamily trichostrongyloidea (H**_O_**TC) * DH: ruminants * Target organ: adults in lumen, larvae in gastric glands * Modest anemia * Protein losing gastropathy * Larvae destroy gastric glands during development * Protein leaked into abomasum, pepsinogen leaked into serum * HCl-producing cells damaged * Abomasal pH goes neutral * Pepsinogen not converte to pepsin (decreased protein digestion) * Loss of acid bacteriostasis (bacterial overgrowth)

Answer 85

* AKA Deer tick * 3 host tick * birds * small mammals * cattle, sheep, horses * Disease vector * Lyme * Super tiny

Answer 86

Must live as parasite to survive.

Answer 87

* Phylum platyhelminthes * Class cestoda (tapeworms) * Order pseudophyllidea * 1st IH: copepod * 2nd IH: frog, rat, snake * Ingests 1st IH * encyst in muscle * DH: dogs, cats * Target organ: small intestine * Paratenic host: humans * Ingest copepod/muscle of 2nd IH: encysts in muscle tissue, periorbital area * Coiled, gravid uterus * Eggs: operculated, contain coracidium (emerges upon contact w/ water) * Prepatent period: 7-14 days * Most cases asymptomatic * V/D, wt loss may occur

Answer 88

* Zoonosis of *Ancylostoma* spp. (strongyloid nematode) * "Sand worms", "plumber's itch", "creeping eruption" * L3 penetrates skin and migrates looking for target * Leaves winding, red pruitic lesions * Rarely enter small intestine to mature

Answer 89

* Phylum nematoda * DH & IH: pigs, rats, bears, wild boar, humans, horses, foxes, other mammals * Target organ: adults in small intestine; larvae in striated muscle * Larviparous * Dx: muscle biopsy, skin sensitivity (humans), ELISA, slaughterhouse inspection

Answer 90

* Recover organisms * Females: vaginal, uterine flush * Males: prepucial wash * PCR * Direct smear * Culture

Answer 91

* Done by some species in order diptera (true-flies) * Normally: eggs deposited in garbage, feces, rotten carrion * **Occasionally: eggs deposited in contaminated wounds** * Early lesions * Dermatitis * Presence of maggots * Pungent odor * Inflammation (have been used medically to clean out necrotic tissue in wounds)

Answer 92

Immature stage consumed. Parasite does not undergo further development. Remains encysted until host is eaten by definitive host.

Answer 93

* Phylum nematoda * Eversible proboscis * Indirect life cycle * IH: arthropod * Adults in small intestine of vertebrates * Fluid filled body cavity

Answer 94

* Phylum nematoda * Long, slender worms * Male has corkscrew tail * Indirect life cycle * IH: arthropod * Larviparous

Answer 95

* Class cestoda (tapeworms) * Order cyclophyllidea * Larva/metacestode * Brood capsules w/ 100s-1000s protoscolices * Unilocular or Multilocular * Multilocular can "bubble-out" and spread like cancer * Zoonotic - humans can be IH

Answer 96

Fleas * Phylum arthropoda * Class insecta * Complex metamorphosis * Only adult is on host * Lays egg on host → egg falls off → larvae & pupae develop off the host * 95% infest mammals * Mate once * Larvae eat frass * Found in crevices, rugs * 2 molts, 3 instars * Vectors (plague)

Answer 97

* Phylum protista * Venereal disease of cattle * 3 anterior flagella * 1 posterior flagella * Undulating membrane * Axostyle (axial rod) * Pseudocyst * Binary fission (asexual) * Causes early embryonic death, abortion

Answer 98

* Free living or parasitic * Eukaryotic * Unicellular * nucleus * mitochondria * ER * Golgi app. * Flagella * Cilia * Pseudopods * Undulating ridges, subpellicular microtubules * Asexual & sexual reproduction * Auto or heterotropic

Answer 99

* Trematode (digenea) * Develops in snail (IH) * Produces rediae or cercariae

Answer 100

* Intestinal parasites - ancylostoma (hookworm) * Collapsing trachea * Allergic bronchitis * Dog * kennel cough * Cat * feline asthma

Answer 101

* Kingdom protista * DH: dogs (esp. sporting & working), cats, opossums, armadillos, racoons, rats, humans * Vector/IH: Reduviid bug * Target organs * Trypomastigote - circulating blood * Amastigote - smooth/cardiac muscle, neural cells

Answer 102

* Female * Feeds on blood * Pilose antennae * Long (anopholene) or short (culicine )palps * Male * Pollinator * Plumose antennae (looks like feather) * Clubbed (anopholene) or long (culicine) palps

Answer 103

* Class cestoda (tapeworms) * Order cyclophyllidea * Larva/metacestode * Single scolex * Not invaginated * Invertebrate IH

Answer 104

* Molecular mimicry * Antigenic variation * Secretion of substances that disable local immune response

Answer 105

Mild to moderate * Mild rad signs * RV enlargement * PA enlargement * Mix alveolar/interstitial pattern * Anemia (\>20% pcv) * Mild proteinuria * +/- live, kidney changes * May be clinically free of clinical signs or show mild signs

Answer 106

Arrested development/dormancy of nematode larvae (usually L4) * More resistant to anthelmentics * Extends prepatent period

Answer 107

* Phylum arthropoda * Segmented body * Head * Thorax * Abdomen

Answer 108

* Kingdom protista * Phylum apicomplexa * Order eucoccidiida * IH: most mammals * Encyst in tissues (liver, lungs, spleen, lymph nodes, brain, heart & skeletal muscle, eye) * DH: felines * Target organ: intestine * Transmission * Acquired: oocysts, raw/undercooked meat * Congenital: transplacental

Answer 109

* Phylum platyhelminthes * Tapeworms * All parasitic * Hermaphroditic * Body of scolex & proglottids * No digestive, circulatory, respiratory, skeletal system

Answer 110

* Nematode * Dog ingests paratenic host w/ encysted L2 → L2 goes directly to stomach → matures in small intestine * No migration

Answer 111

* Phylum platyhelminthes * Class trematoda * Subclass digenea * IH: aquatic snail * DH: cattle, sheep, goats * Target organ: bile ducts * Most pathogenic fluke * Acute/Subacute/Chronic Fascioliasis

Answer 112

* Fecal float * Direct smear of diarrhetic feces * ELISA

Answer 113

* Fecal float * Biopsy/necropsy * IH: schizont rosettes, sarcocysts * Western blot * Ab in serum or CSF (*S. neurona*) * PCR * History of presence of dogs/cats on premises

Answer 114

* Characteristic of nematodes * Eggs retained in uterus * "Gives birth" to live larvae or microfilariae * Ex. *Dirofilaria immitis*

Answer 115

Parasite present in host and causing clinical signs of disease.

Answer 116

* Phylum platyhelminthes * Class cestoda * "True tapeworms" * Scolex (head) * Armed or unarmed * 1-2 sets of reproductive organs * Lateral genital pore * NO uterine pore * Shed gravid proglottid to release egg * Larvae - metacestode * cysticercoid * cysticercus * coenurus * Hyatid cyst

Answer 117

* Phylum platyhelminthes * Class cestoda * "Pseudotapeworms" * Scolex: bothria * 1 set reproductive organs * Genital pore * **Uterine pore: shoot out eggs from proglottid** * Operculated eggs: coracidum * Larvae: metacestode * Procercoid - in 1st IH (copepod) * Plerocercoid/Sparganum - in 2nd IH (vertebrate, frog)

Answer 118

* Three host tick * Rodents, rabbits * Deer, cattle, horses, sheep * Tick paralysis * Disease vector * RMSF * Anaplasma

Answer 119

time from infection until diagnostic stages

Answer 120

* Phylum nematoda * "Pinworms" * Double-bulbed esophagus * Direct life cycle, no migration * Eggs often left on perineal area * Scotch tape test

Answer 121

Sporulated oocyst ingested by DH → Sporozoites excyst → Trophozoite undergoes schizogony (asexual repro) in intestinal epithelium → Type I schizont infects another epithelial cell → Type II schizont → gametogony (merozoites → gametocytes) → microgametocyte (male) and macrogametocyte (female) join → zygote → detatch from epithelium → oocyst → release in feces → sporogony

Answer 122

* Trematode (digena) * Leaves snail (IH) * Has head & tail (resembles sperm) * Will do 1 of 3 things * Infect/penetrate 2nd IH * Encyst on vegetation * Infect/penetrate DH

Answer 123

* Phylum platyhelminthes * Class trematoda * 1st IH: Terrestrial snail * 2nd IH: Anole lizards * Paratenic host: pill bugs * DH: cats * Normally no severe disease * Lizard poisoning: wt. loss, emaciation, D/V, jaundice, death * chronic: englarge bile ducts & gall bladder, liver failure * Target organs: liver, bile duct, pancreatic duct

Answer 124

* Phylum nematoda * Hair-like worms * Tiny mouths * Copulatory bursa (males) * Direct lifestyle * Non-larvated eggs * "HOTC" nematodes - eggs all look the same * DH: ruminants * Target organ: abomasum, small intestine

Answer 125

* Done by species in order diptera (true flies) * Larvae **must use host** to complete life cycle * Adult deposits egg in * Living tissue * **Uncontaminated wounds** * Soft tissue * Will NOT find in feces, garbage * Ex. *Cochliomyia hominivorax* (Definitely do NOT want to use medically. They eat the good stuff.)

Answer 126

* Nematode * Dogs * Ingest egg w/ L2 → larva hatches in duodenum → penetrates intestine → mesenteric lymph nodes → liver → heart → pulmonary arteries → lungs → molts to L3 → alveoli → bronchioles → trachea → coughed up → swallowed → stomach → molts to L4, L5 in small intestine → adult * Prepatent period 3-4 wks * Dog \>3 mos. * Ingest egg w/ L2 → larva hatches in duodenum → penetrates intestine → enters circulation → L2 encysts (hypobiotic) in various tissues, no maturation

Answer 127

* Fecal float * Heartworm Ag test * Mff test * +/- chest rads * +/- CBC, Chemistry

Answer 128

* Caused by trichostrongyloid nematode *Ostertagia ostertagi* * Large number of larvae acquired from pasture * Moroccan leather appearance of abomaum mucosa * Substantial damage of gastric glands during migration (larvae all leave at once) * High egg counts * Rapid onset of clinical signs * Most susceptible in herd are affected * Good prognosis w/ tx * move to clean pasture

Answer 129

* PE every 6-12 mos. * Annual hearthworm test (dogs) * test cats only if clinical signs are present, before placing on prevention * Fecal exam * Puppies \> 1 yr: every 3-6 mos. * Adults: annually * In endemic regions: annual testing for vector-transmitted pathogens

Answer 130

Parasite within host. Infection.

Answer 131

* Phylum nematoda * Superfamily oxyuridae * DH: horse * Target organ: large intestine * Eggs: asymmetrical, operculated, unembryonated when laid * Female deposits egg in perianal region within sticky matrix, where the egg embryonates * Eggs fall into bedding food and the horse ingests them * Pruritis ani/"Seat itch" * risk of secondary bacterial infection * Fecal float not dependable * Scotch-tape test

Answer 132

* Caused by trichostrongyloid nematode *Ostertagia ostertagi* * Uncommon * Ingestion of L3 → hypobiosis in gastric glands * No clinical disease initially * Conditions improve → mass eruption of larvae (can be \>100,000) * Usually yearlings, heifers, older animals * Diagnostic clinical signs: rapid onset of severe PGE in only a few animals * Variable egg counts * High serum pepsinogen (manily looked at in research) * Mucosal reddening, edema

Answer 133

Involves parasites of wild animals infecting humans

Answer 134

Deer fly * Phylum arthropoda * Class insecta * Order diptera * Family tabinidae * Females feed on blood * Males feed on honeydew, nectar * IH/vector * Aquatic larvae * Herbivorous larvae * Insecticides NOT useful

Answer 135

* Phylum nematoda * Very large * 3 anterior lips * Direct life cycle * Non-larvated eggs in feces * thick-shelled, morula

Answer 136

Fluctuating Ag level due to # of female worms, age of worms, quality of sample

Answer 137

* Blood smear * PCR * Biopsy/necropsy of visceral organs * histiocytes - nucleus displace, cytoplasm filled w/ granules

Answer 138

* Phylum platyhelminthes * Class cestoda * Order cyclophyllidea * IH: mite * DH: horse * Target organs: intestines, congregates near ileocecal valve * Adults: short & wide w/ lappets ("bowties") behind each sucker * Metacestode/larvae: cysticercoid * Egg: hexacanth embryo, pyriform apparatus * Predisposes to intussusception, impaction colic * Chronic symptoms: ill thrift, recurrent diarrhea, wt. loss * Indirect & serologic ELISA available

Answer 139

* Phylum nematoda * DH: dogs, cats, ferrets, sea lions, seals * Target organ: R ventricle, pulmonary arteries * IH/Vector: mosquito * Male is smaller w/ spiraled posterior end * Larviparous * Nocturnal and imcomplete periodicity

Answer 140

* Phylum arthropoda * Class arachnida * Order acarina * DH: dogs, cats, foxes, raccoons, ferrets (NOT zoonotic) * Target organ: external ear canal * thick, tarry exudate * Transmission: direct contact * Short, nonjointed pedicels * Females: suckers on leg pairs 1, 2, 4 * Males: suckers on all leg pairs * Permanent parasite * Dx: ear swab & smear

Answer 141

* Phylum nematoda * Superfamily trichostrongyloidea (**_H_**OTC) * DH: ruminants, esp. goats, sheep * Sheep/goats acquire little/no immunity * Prolactin suppresses immunity to worms even more * Periparturient rise * Target organ: abomasum * Lancet tooth at anterior end (for blood sucking) * Major cause of PGE * Anemia * Very fecund (high fertility) * Resistant to most anthelmentics

Answer 142

Horse Fly * Phylum arthropoda * Class insecta * Order diptera * Family tabanidae * Females feed on blood * Males feed on honeydew, nectar * IH/vector * Aquatic larvae * Carnivorous larvae * Insecticides NOT usefull

Answer 143

Mosquitoes * Phylum arthropoda * Class insecta * Order diptera * Subfamilies * Anopholene * *Anopholes* spp. * Culicine * *Aedes* spp. * *Culex* spp. * Larvae are always aquatic * Pupae do not feed

Answer 144

* Class cestoda (tapeworms) * Order cyclophyllidea * Larva/metacestode * Many invaginated scolices (scolex) * Vertebrate IH

Answer 145

Phylum arthropoda Class arachnida

Answer 146

Dalmeny disease in Cattle * intermittent fever * Loss of condition * diarrhea * vaginitis * abortion (last trimester) * mild nervousness * dec. milk yield * anemia * death

Answer 147

* Trematodes (digenea) * Ciliated, penetrates snail

Answer 148

* Phylum arthropoda * Class arachnida * Order acarina * DH: dogs (NOT zoonotic) * Target organ: hair follicles & adjacent sebaceous glands * Permanent parasite * Localized or general demodectid acariasis * Alopecia * Pyoderma * 2° bacterial infections * Transmission: direct contact * Dx: * Deep skin scrape * Look at pustule/abcess contents * May see in fecal float (dog bits at itch, injests mite)

Answer 149

An object mistaken for a parasite in diagnostics (ex. pollen in fecal float)

Answer 150

* Horse is aberrant/dead-end host of *Sarcocystis neurona* * Normal DH: opossum * Normal IH: otter, raccoon, seal, skunk, armadilla * CNS disease * Schizonts destroy neuronal cells while developing * Merozoite release lyses cells * No sarcocysts develop * Lesions in spinal cord, brain, meninges * Clinical signs: head tilt, drooping eye/eyelid, facial paralysis, masseter atrophy, circling, stumbling, falling

Answer 151

* Kingdom protista * Phylum apicomplexa * Order eucoccidiida * Immunity to 1 species does NOT give immunity to others * DH: fish, birds, reptiles, mammals (including humans) * Target organ: intestine (esp. microvillus border) * Small oocysts * Risk of waterborne outbreaks * LOTS of diarrhea!! * yellow, profuse watery * usually self-limiting

Answer 152

Harbors larval/asexual/immature stages of parasite

Answer 153

* Phylum platyhelminthes * Class trematoda * Leaf-like body shape * Schistosomes * Indirect lifestyle * IH usually a snail * Tandem or parallel male sex organs * Usually suck blood from host

Answer 154

* Trematode (digenea) * Encysts in environment or host * Infective stage (DH)

Answer 155

\>1 host (intermediate & definitive hosts.

Answer 156

* Kingdom protista * Phylum apicomplexa * Order Eucoccidiida * Stenoxenous * Monoxenous (direct life cycle) * DH: birds, cattle, small ruminants, horses, rabbits, rodents, pigs * Sexual & asexual reproduction * Oocyst - 4 sporocysts w/ 2 sporozoites each

Answer 157

No intermediate hosts